Presentation on biology "Modern methods of studying humans" (8th grade).
1. One of the main methods for studying the structure of organs, as well as at the descriptive stage of anatomy development, is the dissection of a corpse.
2. The anthropometry method is used to measure external anatomical structures and their relationships, to identify the individual characteristics of a person’s structure.
3. The injection method is used to study body cavities, tubular structures - vessels, bronchi, urinary tract, intestines and others - by filling them with a colored mass.
4. Corrosion method - melting tissue around hollow organs pre-filled with a hardening mass with acid or alkali.
5. The method of clearing organ tissues is the creation of a transparent environment around the pre-colored structure being studied by impregnation with a special liquid.
6. The method of microscopic anatomy is the study of relatively small structures with optical instruments with low magnification.
7. X-ray methods: fluoroscopy - examination of structures under X-rays, radiography - recording structures on X-ray film to study the shape of organs and their functional characteristics in a living person. Computed tomography is also applicable for the study of cadaveric material - layer-by-layer study of organ tissue.
8. The method of transillumination by reflected rays allows you to study small structures lying close to the surface of the organ.
9. Endoscopy - examination of the surface of the mucous membranes of a living person, the color and relief of many internal organs after the introduction of special optical devices inside.
10. Experimental method on animals - to clarify the function of an organ and study its changes under various external influences.
11. Mathematical method - for calculating various quantitative indicators in the relationships of anatomical structures and for obtaining averaged data.
12. Illustration method - creating graphic diagrams of various complex structures by synthesizing individual details of their structure.
13. The ultrasound scanning method is used mainly in a living person to detect changes in the shape and structure of internal organs.
14.Electromagnetic scanning (nuclear magnetic resonance) - a detailed study of the structures of living human organs, based on different intensities of magnetic fields.
These methods are often used in combination in anatomical studies. For example, injection of vessels with a contrast mass, then radiography, preparation, morphometry, mathematical processing, etc.
Structural organization of the human body
One of the basic concepts of anatomy is morphological structure or form, which represents the organization of the morphological substrate in space and has a specific function. Just as there can be no function without structure, there can be no morphological structure without function.
From a morphological point of view, the following levels of organization of the human body structure can be distinguished:
1) organismic (the human body as a whole);
2) organ system (organ systems);
3) organ(s);
4) fabric (fabrics);
5) cellular (cells);
6) subcellular (cellular organelles and corpuscular-fibrillar-membrane structures).
It should be noted that in the presented hierarchical diagram of the structural organization of the human body, a clear subordination can be traced. Organismal, systemic and organ levels of the human body structure are anatomical objects of study. Tissue, cellular and submicroscopic - objects of histological, cytological and ultrastructural studies.
It is advisable to start studying the structural organization of the human body from the simplest morphological level - the cellular level, the main element of which is the cell. The adult human body consists of a huge number of cells (approximately 10 12-14). There are over 14 billion of them in the central nervous system alone.
Cell– the basic elementary structural unit of the body. Textile - historically developed system of the body, which consists of cells of a certain general structure and functions and associated intermediate substance.
Tissues in the body do not exist in isolation. They participate in the construction of organs.
Organ(from organon– tool) is a part of the body that is a relatively integral formation, occupies a certain position, and has a certain shape, structure, and function. An organ has certain relationships with other parts of the body and is built from several tissues, of which, however, one or two predominate, which determines the specific function of one or another organ. For example, the main working tissue of the liver is epithelial; it is built mainly from the hepatic epithelium, which makes up the liver parenchyma. Between the lobules of the liver there are layers of connective tissue, which together with the capsule form the stroma of this organ. The liver has a widely branched network of blood vessels and bile ducts, the walls of which contain smooth muscle tissue. The autonomic nerves that accompany the blood vessels enter the gates of the liver. Thus, all main types of tissues are involved in the structure of the liver. The liver occupies a certain place - the right hypochondrium and the epigastric region of the abdominal cavity, has a certain shape, structure and performs certain functions. During the process of ontogenesis, the number of organs changes; a number of organs exist only in the intrauterine period of development and are absent at later stages of development, for example, gill arches, cloaca, placenta with umbilical cord, etc.
In animals and humans, many organs functionally complement each other. Such collections of organs constitute organ systems and apparatuses.
Organ system- this is a set of organs anatomically and topographically connected to each other, having a similar structure, a common origin in phylo- and ontogenesis and performing general function. For example, the digestive system, consisting of many organs that developed from all parts of the primary intestine, in the body performs the function of digestion as a whole and providing it with nutrients.
Unlike organ systems, there are groups of organs that do not have the same structure and common sources of development, but perform the same function. They're called apparatus. The apparatus combines organs of several systems to perform a complex act. For example, the movement apparatus combines the skeletal system, bone joints, and muscular system. The vocal apparatus - cartilage, ligaments, muscles, laryngeal cavities, oral and nasal cavities.
All human organs can be divided into organs of vegetative and animal, that is, plant and animal life. The first include the digestive, respiratory, genitourinary, cardiovascular and endocrine systems, as they provide body functions inherent in any biological object, including plants. While the musculoskeletal system, sensory organs and nervous system are present only in animals. The organs of animal life are called "soma", within which are the thoracic and abdominal cavities, which contain the entrails. Not a single organ system can exist separately, since together they, mutually complementing and serving each other, represent a qualitatively new structural and functional whole - the organism. At the same time, the body constantly regulates the work of individual organs and systems with the help of the nervous and endocrine systems, which jointly carry out neurohumoral regulation.
The body consists of a number of structures at different levels: from subcellular to the body as a whole. The science of the structure of the body at different levels of organization of its constituent structures in connection with their functions and development is called morphology(from Greek . morphos- form). This term was introduced into natural science at the end of the 18th century by the great German poet Goethe. Anatomy is a narrower concept, since, unlike histology, embryology and pathology, it is a section of morphology that studies mainly those visible to the naked eye, that is, macroscopic objects. Morphology also includes the pathological anatomy mentioned above.
Most of the diagnostic research methods known today, laboratory and instrumental, were created to study structural changes in human organs. Widely used different kinds patient examination, microscopes, biochemical tests, various options X-ray examinations, including those with X-ray contrast agents, various modifications of computer or magnetic resonance imaging devices, ultrasound examinations, fiber-optic instruments, catheters, devices for analyzing the electrical activity of organs (heart, brain), etc. However, even the most modern and very expensive equipment allows only individual study of various human physiological systems and their constituent organs.
Currently, medicine uses the five most informative visual (allowing to obtain images of organs and tissues) methods for examining patients.
X-ray images (radiography). Any modification of this method uses X-rays. Basically, this method allows you to see the components of the human skeleton.
Ultrasound. During ultrasound examination, sound waves emitted by a piezocrystal and reflected by organ tissues are recorded for subsequent construction of layer-by-layer images. The method has limited resolution and low image quality. However, it is relatively safe, practical and cheap, so it is quite often used for diagnosis.
At computed tomography in X-rays (CT method) cross-sectional images of an object are obtained by calculations based on x-ray images taken in many directions. The method allows you to recreate anatomical images with a high level of spatial resolution and in any selected plane.
Nuclear magnetic resonance (NMR, or MR) method, or magnetic resonance imaging (MRI). The research object is placed in the center powerful magnet, which serves to align the magnetic dipoles of various nuclei in the elements of the human body. This balance is disrupted using radiofrequency pulses. The rates at which various atoms and molecules return to their original, stable state are measured using special instruments. This allows you to display not only the density of tissues, but also their biochemical parameters.
Several CT and MR facilities have achieved resolutions of less than one millimeter.
Positron emission tomography (PET) - one of the newest methods for diagnosing the functioning of organs and tissues in the human or animal body using nuclear physics methods.
Let us recall some concepts from school course physics. Radioactive decay or radioactivity- spontaneous change in the composition or structure of atomic nuclei by emission of gamma quanta or elementary particles. Radioactive is any substance that contains radioactive nuclei.
The PET method is based on a phenomenon well known in nuclear physics positron beta decay. The essence of this phenomenon can be explained as follows. Injected into the human body radiopharmaceutical(RP), which is a biologically active compound labeled with a positron-emitting radioactive substance. Next, the radiopharmaceutical is distributed throughout the body through the blood and lymph flows. During radioactive decay in the tissues of a living organism, positrons are the antiparticles of the electron. When a positron interacts with an electron, annihilation(destruction) of two material particles and two are formed gamma quantum (photon) electromagnetic field (two waves). Therefore, the PET method can be called two-photon emission tomography. Next, using special detection equipment, gamma quanta emitted during radioactive decay are recorded.
Thus, PET is a method of three-dimensional examination of the body, based on the ability of radiopharmaceuticals to accumulate in tissues with high biological activity, for example, tumors, brain, heart, etc. It is obvious that, despite the fairly high information content, this method has a number of serious and dangerous side effects.
These methods are the most informative of all existing ones if the patient already has damage to tissues or organs, but none of these methods will help assess how organs actually function. We will further call methods for determining how human organs or systems actually function. functional diagnostics.
Functional diagnostic tools include various modifications of the device Dr. Voll(based on the methods of oriental medicine). In this case, microampere currents flowing through certain channels in the human body are measured. Some current values are considered normal, and deviations from these values in one direction or another are interpreted as disturbances in the functioning of organs or physiological systems in the human body. However, due to the low repeatability of measurement results and a certain subjectivity in the interpretation of the results obtained, the method is not very informative.
Attention!
No study is completely accurate. The worse the patient's condition, the higher the degree of reliability of the results obtained.
Sometimes healthy person detect deviations from the norm (false positive result), but they cannot be identified in the patient (false negative result). The more sensitive and expensive the equipment, the more likely it is that it may indicate the presence of diseases that actually do not exist. To avoid errors or at least reduce their likelihood, during the examination it is necessary to use several fundamentally different techniques.
Attention!
Modern medicine does not have a single method of instrumental diagnosis of human diseases that does not affect the body (diagnosis is often harmful to health).
Attention!
All existing methods for diagnosing a person can only record the fact of the presence of a disease, and the causes of most human diseases are unknown to modern science.
As a rule, all new developments of diagnostic equipment are aimed at increasing the sensitivity (resolution) of existing devices and improving existing research methods. Fundamentally new and safe methods Modern medicine does not yet have diagnostics and study of humans.
Chronology of the development of astronomy since late XIX- throughout the 20th centuries - and beginning of the XXI century
In 1860, the book “Chemical Analysis by Spectral Observations” by Kirchhoff and Bunsen was published, in which methods of spectral analysis were described. The beginning of astrophysics was made.
1862 The satellite of Sirius was discovered, which Bessel spoke about in his research.
1872 American G. Dreper took the first photograph of the spectrum of a star.
1873 J. C. Maxwell publishes A Treatise on Electricity and Magnetism, in which he outlined the so-called Maxwell's equations, thereby predicting the existence electromagnetic waves and the "Light Pressure" effect.
1877 A. Hall discovered the satellites of Mars - Deimos, Phobos. In the same year, Martian canals were discovered by the Italian G. Schiaparelli.
1879 English astronomer J. H. Darwin published a hypothesis about the tidal origin of the Moon. S. Fleming proposes dividing the Earth into time zones.
1884 26 countries adopted the standard time proposed by Fleming. Greenwich was chosen by international agreement as the prime meridian.
1896 A satellite was discovered near Procyon, predicted by Bessel.
1898 W. G. Pickering discovered Saturn's moon Phoebe with its ability to rotate in the opposite direction relative to its planet.
Beginning XX century scientists G. von Zeipel and G. K. Plummer built the first models of stellar systems.
1908 George Hale first discovered a magnetic field in an extraterrestrial object, which became the Sun.
1915-1916 Einstein developed the general theory of relativity, defining a new theory of gravity. The scientist concluded that a change in speed acts on bodies like the force of gravity. If Newton at one time called the orbits of the planets fixed around the Sun, then Einstein argued that the Sun has a gravitational field, as a result of which the orbits of the planets make a slow additional rotation.
1918 American Harlow Shapley, based on observations, developed a model of the structure of the Galaxy, during which the real location of the Sun was revealed - the edge of the Galaxy.
1926-1927 - B. Lindblad and Jan Oort, analyzing the movement of stars, come to the conclusion about the rotation of the Galaxy.
In 1931, radio astronomy began with the experiments of K. Jansky.
1932 Jansky discovered radio emission of cosmic origin. The first radio source of continuous radiation was called the source in the center Milky Way.
1937 American G. Reber designed the first parabolic radio telescope, the diameter of which was 9.5 m.
1950s X-rays emanating from the Sun have been detected. The beginning of X-ray astronomy was laid.
1950s formation of modern infrared astronomy. Study of information in the range between visible radiation.
1953 J. de Vaucouleurs discovered the first supercluster of galaxies, also called the Local.
1957 begins space age launch artificial satellites Earth.
1961 First human launch into space. Yuri Gagarin became the first cosmonaut.
1962 The Orbital Solar Observatory was launched, with the help of which it became possible to systematically carry out observations of ultraviolet radiation, which gave rise to the development of ultraviolet astronomy.
1962 The first X-ray source outside the solar system is discovered - Scorpius X-1.
1965 the first human exit in open space, perfected by Alexey Leonov. The duration of the exit was 23 minutes. 41 sec.
1969 Man's foot set foot on the surface of the Moon. The first astronaut on the surface of the Moon was Neil Armstrong.
1991 launch of the Compton Gamma-ray Observatory, which gave a powerful impetus to the development of gamma-ray astronomy.
Introduction
Almost all of us are carriers of certain genetic defects, and these defects arise constantly throughout our lives. Why do they appear? Is it possible to consider the burden of genetic defects as predestination; perhaps this burden is a consequence of the Fall? Is this really a result of heredity or the influence of the environment in which we live?
These questions concern millions of people, because genetic defects become the causes of severe psychophysical diseases that are difficult to treat, and many are still incurable.
Psychogenetics is a field of knowledge bordering between psychology and genetics, characterizing the relative role and interaction of genetic and environmental factors in the formation of a person’s mental individuality. (SGU, p. 8)
Scientists from various branches of science have been and continue to study the problems of psychogenetics - biologists, geneticists, doctors, theologians, and teachers. F. Galton's research laid the foundation for psychogenetics; thanks to the work of G. Siemens, the twin method was finally formalized, which became one of the main tools of modern psychogenetics. In the two-volume collection of selected works by K.D. Ushinsky there is a special chapter “Heredity of habits and development”, where he recognizes the possibility of inheriting the nervous inclinations of “habits”, which can subsequently, depending on the circumstances, either develop or die out. In 1962, J. Watson, F. Crick and M. Wilkins discovered the structure of DNA, which predetermined almost all subsequent development of biology and genetics. Professor Ted Peters paid attention to the problem of genetic determinism from a theological point of view, considering not only the environment and heredity as factors of development, but most importantly, the individual himself, who is able to control genes.
The methods available to psychogenetics make it possible to very reliably solve its main task: elucidating the role played by hereditary and environmental factors in the formation of psychological and psychophysiological characteristics and individual trajectories of human development.
Thus, relevance This topic is determined by the need to study the role of heredity and environmental factors in the formation of individual psychophysical characteristics, in order to determine the possibility of successful application of the obtained data not only in medicine, but also in Orthodox pedagogy.
Target This work is a theoretical review of modern methods for studying human psychogenetics and determining the scope of application of these studies in Orthodox pedagogy.
Object of study – psychogenetics in a pedagogical context.
Subject of study – modern methods of human psychogenetics.
Realization of this goal involves setting and solving the following tasks :
1) Trace the development of psychogenetics from its origins to the present;
2) Establish a connection between psychogenetic research and pedagogy;
3) Describe modern ideas about the complex influence of heredity and environment on the process of formation of a child’s personality;
4) Study and characterize the methods of psychogenetics;
5) Compare existing techniques and analyze the limitations of each method;
6) Identify areas of application of research data in Orthodox pedagogy;
Work structure . The study consists of an introduction, two chapters, a conclusion, a list of references, and an appendix.
§1.1. Psychogenetics as a scientific discipline.
Stages of development of psychogenetics.
Psychogenetics is an interdisciplinary field of knowledge, bordering between psychology (more precisely, differential psychology) and genetics; The subject of her research is the relative role and interaction of hereditary and environmental factors in the formation of individual differences in psychological and psychophysiological characteristics.
Psychogenetics has relatively recently emerged as an independent science. The beginning of its formation is associated with the name of the English scientist F. Galton. In 1865, he published the article “Hereditary Talent and Character,” which opened a series of his works on human heredity, including “Hereditary Genius: Its Laws and Consequences” (1869), “The History of Twins as a Criterion for the Relative Strength of Nature and Nurture” ( 1876). Thus, F. Galton became the founder of the psychology of individual differences and psychometrics. Period from 1865 to 1900 can be defined as the time of the birth of psychogenetics. The next period is from 1900 to the end of the 30s. characterized by the development of the methodology of psychogenetics, the emergence of psychogenetics as an independent scientific discipline and accumulation of experimental results. In the 40s interest in psychogenetics decreased, which was due to the war, the spread of racism, which was covered by genetics, and the lack of new ideas in the doctrine of heredity. With the discovery in 1953 of the molecular basis of heredity, the prerequisites were created for subsequent successes in psychological research. At this third stage - until the 60s. – psychogenetic studies of intelligence and various mental anomalies were carried out. This stage can be defined as the time of accumulation of empirical material. In 1960, the scientific society “Association of Behavior Genetics” was created and the journal of this society, “Behavior Genetics,” began to be published. This year is considered as the beginning of the modern stage in the development of modern psychogenetics.
In the same year when F. Galton published his works, essays by V.M. were published in Russia. Florinsky “Improvement and degeneration of the human race” (1865). One of important means He considered the improvement of the “human breed” to be the deliberate selection of married couples, so that in the case of the presence of a pathological trait in one of the parents, they could contrast the normal trait of the other parent.
The first study in Russia of the hereditary nature of mental properties belongs to academician K.F. Wolf, who in the 19th century was engaged in the “theory of freaks”, including the transmission of anomalies to offspring. The nature of individual characteristics was also of interest to teachers. In the works of K.D. Ushinsky has a section called “heredity of habits and development of instincts.”
Experimental studies were carried out mainly in two scientific centers: in Petrograd - the Bureau of Eugenics and in Moscow at the Medical-Biological Institute (since 1935, Medical-Genetic). In 1937, the Medical Genetics Institute was closed and work in the field of psychogenetics ceased until the 60s.
Domestic psychogenetic research has resumed as part of the study of the nature of interindividual differences in the properties of the nervous system in the laboratory of B.M. Teplova, then V.B. Nebylitsyna. Since 1972, these studies have been continued in the laboratory of I.V. Ravich-Scherbo at the Research Institute of General and Pedagogical Psychology of the USSR Academy of Pedagogical Sciences. Nowadays, psychogenetic research is carried out in many scientific institutions in our country.
1.2. The importance of psychogenetic research for pedagogy
The uniqueness, uniqueness of the psychological appearance of each person is one of those obvious phenomena of our psyche, which is most vigorously discussed and studied by various sciences. This includes philosophy, psychology, genetics, medicine, many applied sciences and, of course, pedagogy.
In his work, the teacher encounters the fact that people are psychologically different, and strives to understand the origins of this diversity. This intuitive understanding of the psychological diversity of people and the desire to “guess” and diagnose individuality are rooted in the deep past. The treatise “Moral Characters,” the author of which was Aristotle’s friend and successor Theophrastus, describes 30 bright characterological types and their specific manifestations; it contains descriptions large quantity informative psychodiagnostic indicators. Since ancient times, there has been physiognomy (from Greek words meaning: “nature”, “natural inclinations” and “knowledgeable”, “insightful”) - the doctrine of recognizing natural individual characteristics, in particular character, according to the physical characteristics of a person, his appearance. In the middle of the 17th century. Italian doctor C. Baldo published the first work on graphology, “Discourses on the method of recognizing the customs and qualities of a writer from his letter.” Study of characterological types by physical characteristics, handwriting and other indicators continues to this day; it is used to solve a variety of problems, including psychological and pedagogical ones.
In modern pedagogy, there is the concept of a person-oriented approach to teaching and upbringing; its implementation presupposes not only that the teacher has knowledge about a person’s individuality, but also knowledge of methods for diagnosing it. On this basis, the teacher has the opportunity to predict the further development of the individual, as well as correct and optimize it.
An example of the dependence of the effectiveness of learning on the individual characteristics of the student is the work of the German researcher G. Klaus “Introduction to the differential psychology of learning” [Klaus G. Introduction to differential psychology of teaching. M., 1987]. The data from his research suggests that, knowing the dependence of educational success on certain personality characteristics not directly related to a given activity (i.e. not related, for example, to knowledge and skills in a given area), it is possible to optimize human activity, but under one obligatory condition: if the basic individual characteristics are ontogenetically stable.
Data from psychogenetic studies allow teachers to competently organize work with children. This is especially true for correctional work with students with disabilities mental development. It is believed that among children, every tenth child is at risk of an abnormal type of development. This can be criminogenic behavior, episodes of depression or anxiety, as well as a violation of intellectual or emotional development: from a rare form of autism to a specific learning disability, as well as in a condition bordering the clinic and the norm - attention deficit hyperactivity disorder. (SSU, p. 13)
It is very important for a teacher to know the features of the manifestation of such diseases, differentiate them, and master the techniques of working with children prone to mental illness. Psychogenetic data allows us to do this. For example, to make a general assessment of a child's developmental delay, a teacher can use the definition of IQ. The obtained values make it possible to qualify the degree of mental disorder and select optimal ways to solve it. Knowing the characteristics of the intellect, perception and memory of a child susceptible to autism, a teacher can productively conduct correctional work.
Thus, the data from psychogenetic studies are necessary tool both in correctional and educational work of a teacher. They serve as both theoretical support and a practical basis for identifying certain personality traits, which helps the teacher optimize the educational process.
1.3. Modern ideas about the complex influence of heredity and environment on the process of formation of a child’s personality
As already indicated in the introduction, psychogenetics deals with the problems of the role of heredity and environment in the formation of a person’s mental and psychophysiological properties. The purpose of the research is to try to find out how genetic and environmental factors are involved in the formation of the phenotype. More recently, psychologists believed that the characteristics of human behavior are determined almost entirely by the influences of the environment in which development occurs. The merit of psychogenetics is that it drew the attention of scientists to the nature of individual differences in humans. (Alexandrov, p. 28)
Psychogenetics has shown that absolutely identical influences can lead not to an increase in similarity, but to the emergence of differences between people. Different genotypes under the influence of the same environmental influences can form different phenotypes. For example, the same environmental influences are experienced differently by family members and can lead to differences in many mental traits. (Alexandrov, pp. 28-32)
Moreover, simple separation of genetic and environmental influences is in some cases practically impossible. The genotype can actively interact with the environment, to the point that the effects of the environment can to some extent be predetermined by the characteristics of the genotype. Often environmental influences, which are, for example, a risk factor for the occurrence of some pathology, are most clearly manifested in those individuals who have a genetically determined predisposition. (Alexandrov 28-32)
In the context of the psychogenetic study of environmental characteristics, three points are extremely important.
First, genetic research consistently points to the critical role of environmental factors in shaping psychological differences between individuals. Numerous psychogenetic studies have clearly shown how important the role of genetic factors is in explaining interindividual variability in a wide variety of traits. In some cases (for example, for variability in intelligence scores), genetic influences explain 50% of the phenotypic variability. What, however, explains the remaining 50%? The answer to this question is very simple: for the most part, the environment is responsible for the remaining 50%, more precisely, the features of the environment in which carriers of genotypes develop and live.
Secondly, in the context of the genetics of quantitative traits, the concept of environment is defined much more broadly than in psychology. According to this definition, the concept of “environment” includes all types of environmental influences - family-wide, individual and any others (including its physical and physiological components, perinatal conditions, diet, early childhood diseases, etc.), while in psychology environmental conditions are usually equated only to the socio-economic and psychological conditions of the child growing up.
Thirdly, psychogenetics concentrates its efforts on the question of what is (in this moment in a given population), rather than on the question of what might happen. For example, high values of the heritability coefficient obtained when studying interindividual variability in height indicate the fact that at a given time in a given population, the variance in height is explained mainly by genetic differences between members of this population (which is). However, certain environmental interventions (for example, changes in nutrition and increasing the amount of vitamins in the diet) can influence the formation of interindividual differences in the population for such a highly heritable trait as height (which can happen).
In the last 5-10 years, psychogeneticists have discovered three very unexpected phenomena:
a) for children growing up in the same family, the environment creates differences rather than similarities;
b) many psychological instruments (questionnaires, observational data, etc.) used to measure environmental characteristics show an unexpectedly high level of genetic control.
c) when decomposing the phenotypic variance of the overwhelming majority of psychological traits studied by psychogenetics, the role of the general family environment turns out to be insignificant.
All this makes it possible to formulate the hypothesis that people create or find certain environmental conditions that correspond to their genotypes, and are not passive “victims” of their genes or the environment “inherited” to them. In other words, the individual genotype turns out to be the “designer” of the individual environment.
Thus, the study of a genotype is impossible and inadequate without studying the environment in which it is found. The time of contrasting “two factors” - genes and environment - is behind us. Today we know enough to say without a shadow of a doubt: the emerging individuality is not divided into what is from the environment and what is from the genotype. Development is essentially a process of interweaving and interaction of genes and environment, development is their interaction. (Ravich-Scherbo, 122-128)
2.1. general characteristics methods of psychogenetics
Psychogenetics, along with other psychological disciplines such as differential psychology, studies individual differences between people. So why does psychogenetics need its own methods? The thing is that psychogenetics has a common object of study with these disciplines, but its own specific subject. Psychogenetics’ own methods are needed precisely in order to assess the contribution of genetic and environmental factors to the phenotypic diversity of a particular trait in a population.
Psychogenetics methods are experimental designs that are based on comparing people with different numbers of common genes with a parallel analysis of environmental conditions important for the formation of the characteristics being studied. For assessing genetic influences, the ideal situation is when genetically identical people were raised in different environments, and for assessing environmental influences, the ideal situation is when genetically unrelated people were raised in the same environment. Ultimately, studies conducted by psychogenetic methods make it possible to judge such population characteristics as:
Heritability coefficient, or proportion of variability
trait in a population arising due to variability
genotypes.
General environment indicator, general environmental variance, or
the proportion of phenotypic variance due to
variability of the general environment. Phenotypic variance is a measure of the deviation of intelligence from the average value in a sample.
An indicator of the individual environment, individual-environment variance, or the proportion of phenotypic variance that arises due to variability in the individual environment.
Currently, three main methods are used in psychogenetics - the family method, the adopted child method and the twin method. The method of adopted children cannot be used in our country, since there is a legally guaranteed secrecy of adoption. In psychogenetics, population and genealogical methods are also used, but they have low resolution. All five will be described below. listed methods psychogenetics. (Pankratova, pp. 5-8)
2.1. Population method
The population method is based on a comparison of representatives of different populations. By population we mean “a set of freely interbreeding individuals of the same species, occupying a certain area and having a common gene pool in a number of generations” (Shevchenko, Topornina, Stvolinskaya, Human Genetics. Textbook for universities. 2002, p. 23). The genetic structure of the population is preserved provided that there is a free, random formation of parental pairs within the population and marriages do not occur with representatives of other populations. In psychogenetics, representatives of different races are most often compared - Caucasoid, Negroid and Mongoloid. An important point is that population groups are studied taking into account factors such as natural-climatic, economic, social and other living conditions. (Pankratova, p. 9) Genetic characteristics of populations make it possible to establish the gene pool of the population, factors and patterns that determine the preservation of the gene pool or its change over generations. Studying the distribution of mental properties in different populations makes it possible to predict the prevalence of these properties in subsequent generations. The genetic characterization of a population begins with an assessment of the prevalence of the property or trait being studied in the population. Based on data on the prevalence of a trait, the frequencies of genes and corresponding genotypes in the population are determined. (SGU, p. 35)
An example of a population method of psychogenetics is a study of the intellectual abilities of US high school students. Among them are 1,631 representatives of the Caucasian race and 730 representatives of the Negroid race. It was found that the distributions of IQ scores for blacks and whites overlap greatly and that the difference between the average IQ scores of blacks and whites is approximately 15 units (see Figure 3). To explain these results, a genetic hypothesis has been proposed that higher average The IQ of whites, compared to blacks, is related to differences in their gene pools. (Fogel F., Motulski A. Human Genetics. T. 3. M., 1990. With. 137)
Analysis of the results of a population study occurs as follows: if representatives of different races, who are carriers of different gene pools, differ significantly from each other in some psychological or psychophysiological characteristics, then the differences between people in these characteristics are associated with genetic factors. Such reasoning is, to say the least, controversial, since representatives of different races can differ significantly from each other and due to different environmental conditions. To assess the contribution of genetic factors, it is necessary to compare representatives of different races living in identical environmental conditions, that is, having the same families, education, professional opportunities, etc. But it is unlikely that such comparable conditions exist among people living in different cultures.
On the other hand, real populations are rarely completely isolated: people move from one population to another and enter into mixed marriages. For example, the ancestors of modern US blacks were taken from Africa 300 years (about 10 generations) ago. Scientists have calculated that the flow of genes from the white population to the black population occurred at a rate of 3.6% per generation. Thus, in the modern black population of the United States, the share of genes of African ancestors is 0.694 of total number genes. In other words, African blacks inherited about 30% of their genes from the white population. As a result, differences within a population become wider than differences between populations. (Pankratova, 9-11)
Thus, the population method of psychogenetics is used to determine the genotypes of populations and predict the mental properties of populations in subsequent generations. But this method has low resolution due to the impossibility of creating identical conditions for different populations and the impossibility of isolating them from each other - all this becomes a limitation of the method and an obstacle to establishing the gene pool of a population.
2.3. Genealogical method
The genealogical method (analysis of pedigrees) is based on comparison of representatives one family in a series of generations. In order to make this comparison more clear, the pedigree is depicted graphically using special symbols (see Figure 4). When compiling genealogists chetical tree exist certain rules. Thus, the symbols of representatives of one generation are located in one line of the pedigree. Generations are numbered in the direction from previous generations to the present and are indicated to the left of the pedigree in Roman numerals. The designations of children in each family are arranged from left to right in order of birth and are labeled by numbers or years of life.
When analyzing a pedigree, the researcher analyzes the manifestation of a trait in a number of generations. If the sign repeats itself in a series of generations, it is concluded that genetic the nature of individual differences in this trait. For example, when analyzing the pedigree of the Bernoulli family, we see that in a number of generations there are people with mathematical abilities (see Figure 5). For a researcher, such a number of mathematicians in a family indicates the genetic nature of mathematical abilities. But if we start studying the biography of the Bernoulli family, we will find a lot environmental factors that influenced the development of mathematical abilities (for example, the father was his sons' teacher in mathematics, an uncle involved his nephews in his work in mathematics, the family had a common circle of mathematician friends, etc.). On the other hand, it is not entirely clear how equivalent the mathematical abilities of different representatives of the Bernoulli family are, because The presence or absence of a sign is assessed, and not the degree of its severity.
Thus, the genealogical method does not allow exactly answer the question whether, due to genetic or environmental factors, the studied trait is repeated over a number of generations. But this method allows you to determine type of inheritance various kinds of signs (for example, diseases or abnormal appearance) and make a forecast for the future. The carrier of the characteristic we are interested in is called proband. In a series of generations on the family tree, people who have a trait are designated (for example, affected by a given disease). Next, the logic of repetition of the characteristic is analyzed and the type of inheritance is established. For example, Figure 6 shows the pedigree of a person with hypertrichosis. Hypertrichosis is the presence of hair along the edges of the ears. As can be seen from the pedigree, this trait is always transmitted to sons and never to daughters, that is, we can talk about a Y-linked type of inheritance. (Pankratova, pp. 11-14)
Thus, genealogical research by itself, without combining with other methods, has a very low resolution and does not allow one to reliably “separate” the genetic and environmental components of the variance of a psychological trait. Although, when combined with other methods, for example with twins, family data make it possible to solve questions that are impossible to solve without them (for example, to clarify the type of hereditary transmission - additive or dominant), or to control environmental variables (for example, the general family and individual environment, the effect twinhood). (Ravich-Scherbo, p.162)
The genealogical method can be useful for teachers in the educational process for the competent selection of teaching methods and principles, organizing correctional work with children.
2.4. Family method
Among the methods of psychogenetics, some researchers highlight the family method, which involves comparing representatives one family, which have different numbers of genes in common (see Figure 7). Family members (at least two groups of relatives) are compared in pairs: brothers and sisters (siblings), cousins, second cousins, parents and children, grandparents, grandparents, aunts and nieces, uncles and nephews, etc. All these pairs of relatives, based on the number of common genes, can be divided into closer (have more common genes) and less close (have fewer common genes) relatives (see Table 1).
The logic of the method is that if, according to the trait being studied, closer relatives (who have more common genes) are more similar in comparison with less close relatives (who have fewer common genes), then individual differences in this trait are associated with genetic factors.
But the greater similarity between relatives with a greater degree of relatedness may also be due to environmental factors, since closer relatives, as a rule, have more similar living conditions. In order to increase family reliability research, it is necessary to compare samples of less close relatives who do not usually live together. For example, comparing first cousins with second cousins will make it possible to more accurately determine the role of genotype and environment in the formation of individual differences in a given trait than comparing first siblings with first cousins.
In addition, in family research there are problems when comparing representatives different generations(eg parents and children). These problems are associated with the fact that the compared relatives are separated by a fairly large age interval. On the one hand, the influence of genotype on the studied traits may change with age. On the other hand, diagnosing people of different ages can produce disparate results. To overcome these difficulties, it is necessary to survey representatives of different generations at the same age. This is only possible when conducting a longitudinal study, that is, when re-testing representatives of the younger generation when they reach the age at which representatives of the older generation were examined. (Pankratova 14-17)
Thus, the family method makes it possible to fairly accurately assess the contribution of heredity and environment to the formation of individual differences. However, family research itself has a very low resolution, but the integration of several methods simultaneously makes it possible to resolve controversial issues when interpreting the results. (Pankratova, pp. 28-29)
2.5. Adopted children method
When using the method, adopted children are compared reception children with biological parents and with parents- adoptive parents. For the study, children are selected who were given up to be raised by other people's families as early as possible (preferably in the first days of life). An adopted child shares 50% of their genes with their biological parents, and shares a common environment with their adoptive parents. Thus, if an adopted child is more similar to his biological parents in some psychological or psychophysiological characteristic, then the researcher concludes that individual differences in this characteristic are more related to genotype. And if the adopted child is more similar to the adoptive parents, then these differences are associated with environment.(Pankratova, p. 17)
The first work done using this method was published in 1924. The results, from the author’s point of view, indicate that the intelligence of adopted children depends more on social status biological parents than adoptive ones. However, as noted by R. Plomin and co-authors, this work had a number of defects: only 35% of the 910 children examined were adopted before the age of 5; The measurement of mental abilities was carried out on a fairly rough (only three-point) scale. The presence of such flaws makes a meaningful analysis of the study difficult.
25 years later, in 1949, the first work based on the complete scheme of the method appeared. It was followed by others, the largest of which were two modern programs: Texas and Colorado Adopted Children Research Projects.
One of the very interesting and informative variants of the method is the study of the so-called adopted (adoptive) siblings, i.e. several non-relative children adopted by one family. Considering that such children do not have common genes, their similarity (if it is detected) can only be the result of the action of the general family environment.
There are two schemes for this method: full and partial. The first involves combining data obtained from two groups: separated relatives (biological parents and their children given to adoptive parents; separated siblings) and adopted siblings; the second - either one or another group of data. In the first case, as R. Plomin and his co-authors write, there are “genetic” parents (biological parents and their adopted children), “environmental” parents (adoptive parents with their adopted children) and, as a control, an additional group of “genetic plus environmental” parents (regular biological family). A comparison of these three groups makes it possible to reliably “separate” the factors that form family resemblance.
Using the method of adoptive families, it is shown that in an equally good environment, the distribution of IQ scores of adopted children is shifted towards high values if the biological parents had high intelligence, and towards low values if they had reduced intelligence. (These kinds of results prompted a witty remark from one of the psychogeneticists: “It is best to assume that intelligence is 100% dependent on genes and 100% on the environment.”)
Possible limitations of the method are related to several problems. First, how representative of the population is the group of women who give away their children? But it can be controlled. For example, in the largest program, the Colorado Adoptive Children Study, all participants (245 biological parents, their adopted children and adoptive parents, as well as 245 control families with biological and adopted siblings) were representative of the general population in terms of cognitive characteristics, personal characteristics, family environment, educational and socio-economic status. The authors note that even if for some parameters the samples turn out to deviate from population distributions, this should be taken into account when interpreting the results, but does not give reason to consider the method invalid.
Secondly, a more specific question arises about the selectivity of placing children in foster families: are there any similarities between natural and foster parents in any respects? It is clear that such similarity will increase the correlation in child-adoptive pairs, if the trait under study is determined by heredity, and in child-biological parent pairs, if it is largely determined by the environment. In either case, estimates of the genetic or environmental component of variation for a given trait will be biased.
Thirdly, there is the problem of perinatal influences of the mother’s body on the characteristics of the unborn child, which should increase the similarity of the mother and the given child due to intrauterine, but environmental, rather than genetic factors. According to some researchers, by the time of birth the human fetus already has some experience. If this is so, then the similarity between the biological mother and the given-up child may have a non-genetic origin. As a result, some researchers even believe that the method of adopted children is very informative for studying various postnatal environmental influences, but not for solving the genotype-environment problem.
There are also more subtle circumstances that are important for evaluating the method. For example, the possibility of forming subjective legends about natural parents in a situation where a child knows that he is not his own in this family. In experimental work, this creates an uncontrollable interference, since such a legend can turn out to be a rather serious educational factor.
In our country it is impossible to use this method, since we have a legally guaranteed secrecy of adoption. This is a humane, pedagogically absolutely correct decision, but it means that the researcher does not have the right to seek information either about adopted children, or, especially, about their biological parents.
Thus, the current ideas about the limitations and conditions for using the method of adopted children are described, reasoned, and for the most part can be either controlled or taken into account when interpreting the results obtained. Therefore, it is one of the main methods of modern psychogenetics. (Ravich-Scherbo, pp. 162-165)
2.6. Twin method
The first attempt to use twins to solve the problem of “nature and nurture” belongs, as already mentioned, to F. Galton, who intuitively foresaw what became a scientific truth and a serious method of research only several decades later. The fascination with twins was a fairly typical phenomenon in science at the end of the 19th and beginning of the 20th centuries. We studied their biology, pathology, origin, etc. We also find twin works in many famous psychologists of that time: E. Thorndike, S. Merriman, G. Siemens, etc. (Ravich-Scherbo, p. 165)
There are several varieties of the twin method (see Table 2). Classical a variant of the twin method is based on comparing two types twins - monozygotic (MZ) and dizygotic (DZ). Monozygotic twins develop from one fertilized egg (one zygotes), which is on early stages division gives rise to two organisms (necessarily of the same sex). Thus, MZ twins are the only people on Earth who have the same sets of genes (100% common genes). In turn, dizygotic twins develop from two fertilized eggs (from two zygotes). From a genetic point of view, DZ twins are siblings with an average 50% common genes. The difference lies only in the simultaneous development and birth of two children of the same or different sex. Note that opposite-sex pairs of DZ twins are included in a psychogenetic study to assess the influence of the gender factor on individual differences.
The twin method is based on two main assumptions. First: it is assumed equality environmental influences on the development of MZ and DZ twins. If this postulate is violated, the magnitude of heritability indicators and other components of phenotypic variance is distorted. Second: none systematic differences between twins and singletons. If this postulate is violated, the conclusions of a psychogenetic study cannot be generalized to the entire population.
When using the classic version of the twin method, two groups consisting of members of the MZ and DZ twin pairs are first recruited. Then the similarity in pairs of MZ and similarity in pairs of DZ twins are assessed (intra-pair similarity) according to the characteristic being studied. The intrapair similarity in the group of MZ twins is then compared with the intrapair similarity in the group of DZ twins (see Figure 9).
Logics The method is as follows. MZ twins share 100% of their genes, DZ twins share an average of 50% of their genes. At the same time, the equality of environmental influences on the development of MZ and DZ twins is postulated. The similarity between members of twin pairs is determined by both genotype and environment. Consequently, if the measure of intrapair similarity of MZ twins is higher than the measure of intrapair similarity of DZ twins, then individual differences in the trait under study are more associated with genetic factors.
When conducting psychogenetic research using the twin method, the question may arise about zygosity twins, because It is not always easy to determine by eye whether twins are monozygotic or dizygotic. To determine the zygosity of twins, different methods, starting from assessing the external similarity of twins and ending with a biochemical blood test. The simplest
A way to determine zygosity is to compare twins according to a number of characteristics that are hereditarily given and do not change under the influence of the environment. These include eye and hair color, shape of lips, ears, nose and nostrils, fingerprints, etc. When examining a large sample of twins, parents or other experts are asked to fill out a questionnaire about the similarity of the twins' physical features and whether other people confuse the twins.
Restrictions The twin method is associated with possible environmental differences in the perinatal and postnatal development of MZ and DZ twins, as well as twins and singletons, to whom the results of the twin study are transferred.
Differences in perinatal development may occur due to unequal blood supply to MZ twins compared to DZ twins. This is due to the fact that MZ twins quite often have one set of membranes between them, and DZ twins always have separate sets. As a result, the difference in oxygen supply and nutrients through the blood leads to a greater difference in the birth weight of MZ twins compared to DZ twins. In turn, the differences in the perinatal development of twins and single-born children are due to the fact that in the first case, two children are simultaneously provided with oxygen and nutrients, and in the second case, only one. Therefore, during multiple pregnancies, newborns are on average physically less developed compared to single-born children.
Environmental conditions in postnatal The development of MZ and DZ twins may also differ. For example, the similarity of MZ twins is often specifically emphasized by parents (children are dressed alike, given similar names, treated similarly), which is less typical for DZ twins. MZ twins are more likely than DZ twins to be together, have the same circle of friends, the same hobbies, etc. Such greater environmental similarity in pairs of MZ twins, compared to pairs of DZ twins, may lead to additional non-genetic similarity of MZ twins, which contradicts the assumption of environmental equality in MZ and DZ pairs. Another example: environmental features can increase differences between members of both MZ and DZ pairs (the desire to be different from the co-twin, the distribution of roles in the pair, different relationships children with their parents). The influence of a specific twin environment on the similarity of both MZ and DZ twins can be very different. In turn, single-born children, unlike MZ and DZ twins, develop outside the specific twin environment, which can have a significant impact on the formation of the child’s psychological characteristics.
Thus, the limitations of the twin method are related to pre- and postnatal environmental conditions developments that can increase or decrease the similarity between members of twin pairs. If the postulate of equality of environments violated and the common environment makes different contributions to the similarity of MZ and DZ twins for the trait being studied:
1) may increase or decrease intrapair
similarity of twins - either MZ, or DZ, or both types
twins;
2) intrapair similarity of twins of different types can
change as unidirectionally (for example, it decreases
similarity in pairs of both MZ and DZ twins), and different
directionally (for example, the similarity in pairs of MH and
similarity decreases in pairs of DZ twins).
To overcome these limitations of the method, it is necessary to evaluate the sensitivity studied signs to the characteristics of the twin environment, that is check the postulate about the equality of the environments of MZ and DZ twins and the postulate about the representativeness of a sample of twins to a sample of single-born children. Thus, it is possible to assess the relationship between weight at birth and subsequent psychological development child; determine whether the features of the twin MZ environment are more similar and whether this affects the level of psychological similarity, for example, in temperamental properties; check whether there are significant differences in this trait between twins and singletons, etc.
2.7. Conclusions on the second chapter
Thus, the family method, the method of adopted children and the twin method allow the most accurate assessment of the contribution of heredity and environment to the formation of individual differences. These methods can be divided into “hard” and “non-hard” experimental designs. The method of adopted children and the method of separated twins make it possible to clearly distinguish the influence of genetic and environmental factors, while the classical version of the twin method and the family method require additional validation. In the case of the classical twin method, it is necessary to conduct additional research to verify the postulate about the equality of the environments of MZ and DZ twins. In the case of the family method, to increase reliability, distant relatives are compared, who, as a rule, live and are raised in different environmental conditions.
It is worth noting that family research itself has a very low resolution. But including family data in a study of adopted children (comparing adopted children with siblings and step-siblings) or in a twin study (comparing MZ and DZ twins with parents and siblings) can resolve controversial issues in the interpretation of results. For example, combining the family method with the twin method helps to understand the type of inheritance (additive or non-additive) and control for environmental variables (general and individual environment, twinning effect).
If only one of the psychogenetics methods is used in a study, it is recommended to compare the data obtained with the results of studies conducted using other methods. This will help more accurately interpret the results obtained and, ultimately, more accurately understand the nature of individual differences in the psychological or psychophysiological characteristics being studied. As an example, Table 4 shows data on intelligence obtained using different methods. This table shows that similarity in intelligence increases monotonically as the genetic similarity of the people being compared increases.
Contraindications are the patient's serious condition, acute liver and kidney diseases, and intolerance to iodine drugs, which are injected into the vascular bed through a special catheter. 1-2 days before the study, a test is performed to determine the patient’s tolerance to iodine preparations. During the examination, local anesthesia or general anesthesia is used.
The images are obtained using a conventional X-ray machine. When converters are used with a television device, the radiation exposure to the patient is significantly reduced.
AUDIOMETRY. - Measurement of hearing acuity, i.e. sensitivity of the auditory organ to sounds different heights. It consists mainly in maintaining the lowest sound intensity at which it is still audible. Three main methods are used: hearing testing with speech, tuning forks, and audiometer.
The simplest and most accessible method is speech hearing testing. Its advantage is the ability to conduct an examination without special instruments; in addition, this method corresponds to the main role of the auditory function - to serve as a means of speech communication. Under normal conditions, hearing is considered normal when perceiving whispered speech at a distance of 6-7 meters.
When using equipment, the results of the study are recorded on a special form: this audiogram gives an idea of the degree of hearing impairment and the location of the lesion.
BIOPSY. - Intravital excision of tissues or organs for examination under a microscope. It allows you to accurately determine the existing pathology, as well as diagnose clinically unclear and initial stages of neoplasms, and recognize various inflammatory phenomena. Repeated biopsy traces the dynamics of the pathological process and the influence of therapeutic measures on it.
In modern clinics and hospitals, a biopsy is performed on every third patient; the material for it can be taken from almost any organ with special instruments.
BRONCHOSCOPY. - A diagnostic and therapeutic procedure consisting of a visual assessment of the condition of the bronchial tree using a special device - a bronchoscope. It is carried out to diagnose tumors of the trachea and bronchi (taking a biopsy), to remove foreign bodies from the respiratory tract, to straighten sleeping areas of lung tissue (atelectasis), to wash the bronchi and introduce medications into them.
Bronchoscopy can be performed under local anesthesia and general anesthesia. With local anesthesia, the root of the tongue, pharynx, trachea and main bronchi are lubricated with a solution of dicaine. An anesthetic spray can also be used. For general anesthesia, general anesthesia is most often used. The study is carried out in a sitting or supine position.
VECTORCARDIOGRAPHY. - Registration of the electrical activity of the heart using special devices - vector electrocardioscopes. Allows you to determine changes in the magnitude and direction of the electrical field of the heart during the cardiac cycle. The method is a further development of electrocardiography. In the clinic, it is used to diagnose focal myocardial lesions, ventricular hypertrophy (especially in the early stages) and rhythm disturbances.
Research is carried out with the patient in the supine position, applying electrodes to the surface of the chest. The resulting potential difference is recorded on the screen of the cathode ray tube.
CARDIAC CATHETERIZATION.- Introduction of special catheters into the cavities of the heart through peripheral veins and arteries. Used to diagnose complex heart defects, clarify indications and contraindications for surgical treatment of a number of diseases of the heart, blood vessels and lungs, to identify and evaluate cardiac, coronary and pulmonary insufficiency.
Catheterization does not require any special preparation of the patient. It is usually carried out in the morning (on an empty stomach) in a cath lab (with special equipment) by professionally trained doctors. The technique is based on the introduction of catheters into the heart through the aorta by puncture of the right femoral artery. After the study, patients need bed rest for the first 24 hours.
Catheterization allows you to study the structure and function of all parts of the cardiovascular system. With its help, you can determine the exact location and size of individual cavities of the heart and large vessels, identify defects in the septa of the heart, and also detect abnormal discharge of blood vessels. Through the catheter, you can record blood pressure, electrocardiogram and phonocardiogram, and obtain blood samples from parts of the heart and great vessels.
It is also used for medicinal purposes for administering medications. In addition, using special catheters, heart surgery is performed (occlusion of the patent ductus arteriosus, elimination of valve stenosis). It is possible that as bloodless research methods (such as ultrasound, etc.) improve, cardiac catheterization will be used less frequently for diagnostic purposes, and more often for therapeutic purposes.
LAPAROSCOPY. - A method for diagnosing diseases of the abdominal cavity using a special optical instrument, which is inserted through a puncture of the anterior abdominal wall or posterior vaginal fornix. Provides instrumental palpation and obtaining biopsy material for more accurate histological studies; if the clinical diagnosis is unclear, it helps to establish the form or stage of the disease. If necessary, serves for therapeutic measures: placement of drainage, removal of foreign bodies, electrocoagulation, organ puncture.
Planned laparoscopy is performed after preliminary clinical, laboratory and x-ray examination and is the final stage of diagnosis. Emergency laparoscopy is performed for acutely developed pathology of the abdominal organs. Both are performed under local anesthesia in most cases. A diagnostic laparoscope is a special device with fiber optics, intended only for examining organs. The manipulation laparoscope has an additional special channel for introducing various devices that allow biopsy, coagulation, etc.
The first stage of a laparoscopic examination is the introduction of oxygen or air through a needle into the abdominal cavity to increase the viewing sector. The second stage is the introduction of an optical tube into the abdominal cavity. The third stage is examination of the abdominal cavity. Then the laparoscope is removed, the air is removed, and sutures are placed on the skin wound. The patient is prescribed bed rest, painkillers, and cold on the stomach for 24 hours.
MONITOR SURVEILLANCE. - It is carried out over several hours or days with continuous recording of the body’s condition. Monitoring is carried out over pulse and respiration rates, arterial and venous pressure, body temperature, electrocardiogram, etc.
Typically, monitoring is used: 1) for immediate detection of conditions that threaten the patient’s life and provision of emergency assistance; 2) to record changes over a given time, for example, to record extrasystoles. In the first case, stationary monitors are used, equipped with an alarm that is automatically turned on when the values of the indicators deviate beyond the limits set by the doctor. Such control is established over a patient with life-threatening complications - disturbances in heart rhythm, blood pressure, breathing, etc. In other cases, portable devices are used that allow long-term and continuous recording of an ECG on a slowly moving magnetic tape. The portable monitor is mounted on a belt thrown over the patient's shoulder, or on an elastic belt.
RADIOISOTOPIC DIAGNOSTICS.- Recognition of pathological changes in the human body using radioactive compounds. It is based on recording and measuring radiation from drugs introduced into the body. With their help, they study the functioning of organs and systems, metabolism, blood flow speed and other processes.
In radioisotope diagnostics, two methods are used: 1) The patient is injected with a radiopharmaceutical drug, followed by a study of its movement or unequal concentration in organs and tissues. 2) Labeled substances are added to the test tube with the blood being tested, assessing their interaction. This is etc. a screening test for the early detection of various diseases in an unlimited number of people.
Indications for radioisotope research are diseases of the endocrine glands, digestive organs, as well as the bone, cardiovascular, hematopoietic systems, brain and spinal cord, lungs, excretory organs, and lymphatic system. It is carried out not only if some pathology is suspected or if there is a known disease, but also to clarify the extent of the lesion and assess the effectiveness of treatment. There are no contraindications to radioisotope research; there are only some restrictions. Comparison of radioisotope, X-ray and ultrasound data is of great importance.
There are six main methods of radioisotope diagnostics: clinical radiometry, radiography, whole body radiometry, scanning and scintigraphy, determination of radioactivity of biological samples, radioisotope study of biological samples in vitro.
Clinical radiometry determines the concentration of radiopharmaceuticals in organs and tissues of the body by measuring radioactivity over a time interval. Intended for the diagnosis of tumors located on the surface of the skin, eyes, mucous membrane of the larynx, esophagus, stomach, uterus and other organs.
Radiography – registration of the dynamics of accumulation and redistribution of the administered radioactive drug by the organ. It is used to study rapidly occurring processes, such as blood circulation, ventilation, etc.
Radiometry - the whole body - is carried out using a special counter. The method is intended to study the metabolism of proteins, vitamins, the function of the gastrointestinal tract, as well as to study the natural radioactivity of the body and its contamination with radioactive decay products.
Scanning and scintigraphy
Determination of radioactivity of biological samples - intended to study the function of an organ. The absolute or relative radioactivity of urine, blood serum, saliva, etc. is considered.
Radioisotope research in vitro - determination of the concentration of hormones and other biologically active substances in the blood. In this case, radionuclides and labeled compounds are not introduced into the body; All analysis is based on in vitro data.
Each diagnostic test is based on the participation of radionuclides in physiological processes body. Circulating along with blood and lymph, drugs are temporarily retained in certain organs, their speed and direction are recorded, on the basis of which a clinical opinion is made.
In gastroenterology, this makes it possible to study the function, position and size of the salivary glands, spleen, and the condition of the gastrointestinal tract. Various aspects of liver activity and the state of its blood circulation are determined: scanning and scintigraphy give an idea of focal and diffuse changes in chronic hepatitis, cirrhosis, echinococcosis and malignant neoplasms. When scintigraphy of the pancreas, obtaining its image, inflammatory and volumetric changes are analyzed. With the help of labeled food, the functions of the stomach and duodenum are studied in chronic gastroenteritis and peptic ulcers.
In hematology, radioisotope diagnostics helps to establish the life expectancy of red blood cells and determine anemia. In cardiology, the movement of blood through the vessels and cavities of the heart is traced: based on the nature of the distribution of the drug in its healthy and affected areas, a reasonable conclusion is made about the state of the myocardium. Sciptigraphy provides important data for the diagnosis of myocardial infarction - an image of the heart with areas of necrosis. Radiocardiography plays a great role in recognizing congenital and acquired heart defects. Using a special device - a gamma camera, it helps to see the heart and large vessels at work.
In neurology, radioisotope techniques are used to identify brain tumors, their nature, location and prevalence. Renography is the most physiological test for kidney diseases: an image of the organ, its location, function.
The advent of radioisotope technology has opened up new opportunities for oncology. Radionuclides selectively accumulating in tumors have made it possible to diagnose primary cancers of the lungs, intestines, pancreas, lymphatic and central nervous systems, since even small tumors are detected. This allows you to evaluate the effectiveness of treatment and identify relapses. Moreover, scintigraphic signs of bone metastases are detected 3-12 months earlier than x-rays.
In pulmonology, these methods “hear” external respiration and pulmonary blood flow; in endocrinology, they “see” the consequences of disorders of iodine and other metabolism, calculating the concentration of hormones - the result of the activity of the endocrine glands.
All studies are carried out only in radioisotope diagnostic laboratories by specially trained personnel. Radiation safety is ensured by calculating the optimal activity of the administered radionuclide. Patient radiation doses are clearly regulated.
RHEOGRAPHY- (literal Translation: "reo" - flow, flow and its graphic representation). A method for studying blood circulation based on measuring the pulse wave caused by the resistance of the vessel wall when an electric current is passed. It is used in the diagnosis of various types of vascular disorders of the brain, limbs, lungs, heart, liver, etc.
Rheography of the extremities is used for diseases of peripheral vessels, accompanied by changes in their tone, elasticity, narrowing or complete blockage of the arteries. The rheogram is recorded from symmetrical areas of both limbs, onto which electrodes of the same area, 1020 mm wide, are applied. To find out the adaptive capabilities of the vascular system, tests with nitroglycerin, physical activity, and cold are used.
RHEOGEPATOGRAPHY– study of liver blood flow. By recording fluctuations in the electrical resistance of its tissues, it allows us to judge the processes occurring in the vascular system of the liver: blood supply, lesions, especially in acute and chronic hepatitis and cirrhosis.
It is carried out on an empty stomach, with the patient lying on his back, in some cases after a pharmacological load (papaverine, euphyllia, nosh-pa).
RHEOCARDIOGRAPHY– study of cardiac activity, the dynamics of blood filling of large vessels during the cardiac cycle.
Rheopulmonography– consists of recording the electrical resistance of lung tissue, used for bronchopulmonary pathology. It is of particular importance in surgery, since a rheopulmonogram can be taken from any part of the lung directly during surgery. This is necessary in cases where preoperative examination does not allow us to provide a sufficiently accurate conclusion about the condition of the lung segments bordering the affected ones, and it is necessary to clarify the expected extent of resection.
RHEOENCEPHALOGRAPHY– determines the tone and elasticity of brain vessels, measuring their resistance to high-frequency current, weak in strength and voltage. It also allows you to determine the blood supply to parts of the brain, diagnose the nature and location of its lesions, gives good result for vascular diseases, especially cerebral atherosclerosis. In the acute period of stroke, it helps to establish the ischemic nature of the circulatory disorder or thromboembolic cerebral infarction. Rheoencephalography is promising for brain injuries, brain tumors, epilepsy, migraine, etc. This method is used in the study of fetal hemodynamics during childbirth.
X-RAY DIAGNOSTICS.- Recognition of injuries and diseases of various human organs and systems based on obtaining and analyzing their X-ray images.
In this study, the beam x-rays, passing through organs and tissues, is absorbed by them to an unequal extent and at the exit becomes heterogeneous. Therefore, when it then hits the screen or film, it causes the effect of shadow exposure, consisting of light and darker areas of the body.
At the dawn of radiology, its area of application was only the respiratory organs and skeleton. Today the range is much wider: the gastrointestinal, biliary and urinary tracts, kidneys, blood and lymphatic vessels, etc.
The main tasks of X-ray diagnostics are: to establish whether the patient has any disease and to identify its distinctive signs in order to differentiate it from other pathological processes; accurately determine the location and extent of the lesion, the presence of complications; rate general condition sick.
Organs and tissues of the body differ from each other in density and ability to be x-rayed. So, well, bones and joints, lungs, heart are visible. When X-raying the gastrointestinal tract, liver, kidneys, bronchi, and blood vessels, the natural contrast of which is insufficient, they resort to artificial contrast, specially introducing harmless radiopaque substances into the body. These include barium sulfate and organic iodide compounds. They are taken orally (when the stomach is examined), injected into the bloodstream intravenously (during urography of the kidneys and urinary tract) or directly into the organ cavity (for example, during bronchography).
Indications for x-ray examination are extremely wide. The choice of the optimal method is determined by the diagnostic task in each specific case. They usually start with fluoroscopy or radiography.
X-RAY SCOPE- This is the acquisition of an x-ray image on a screen. Can be used anywhere there is an X-ray diagnostic machine. Allows you to examine organs in the process of their work - respiratory movements of the diaphragm, heart contraction, peristalsis of the esophagus, stomach, intestines. You can also visually determine the relative position of organs, the localization and displacement of pathological formations. Many diagnostic and therapeutic procedures, such as vascular catheterization, are performed under fluoroscopy control.
However, lower resolution than radiography and the inability to objectively document the results reduce the value of the method.
Radiography is the production of a fixed image of any part of the body using x-rays on a material sensitive to it, usually photographic film. It is the leading method for studying the osteoarticular apparatus, lungs, heart, and diaphragm. The advantages include the detail of the image, the presence of an x-ray that can be stored for a long time for comparison with previous and subsequent x-rays. The radiation exposure to the patient is less than with fluoroscopy.
To obtain additional information about the organ under study, they resort to special x-ray methods, such as fluorography, tomography, electroradiography, etc., based on their technical means.
THERMOGRAPHY– a method for recording infrared radiation from the surface of the human body. It is used in oncology for the differential diagnosis of tumors of the mammary, salivary and thyroid glands, bone diseases, cancer metastases in bones and soft tissues.
The physiological basis of thermography is an increase in the intensity of thermal radiation over pathological foci due to increased blood supply and metabolic processes in them. A decrease in blood flow in tissues and organs is reflected by the “fading” of their thermal field.
Preparing the patient includes avoiding taking hormonal medications, medications that affect vascular tone, and applying any ointments for ten days. Thermography of the abdominal organs is carried out on an empty stomach, and the mammary glands - on the 8-10th day of the menstrual cycle. There are no contraindications, the study can be repeated many times. As an independent diagnostic method, it is rarely used; comparison with the data of the clinical and radiological examination of the patient is mandatory.
TOMOGRAPHY(Greek tomos piece, layer + graphō write, depict) - a method of layer-by-layer examination of the organs of the human body using radiation diagnostics. There are methods of T. using ionizing radiation, i.e. with irradiation of patients (conventional X-ray, or so-called classical, computer X-ray and radionuclide, or emission computer, T.), and not related to it (ultrasound and magnetic resonance T.). With the exception of conventional X-ray, for all types of tomography, images are obtained using computers (computers) built into the devices.
Conventional X-ray tomography - the most common method of layer-by-layer research; is based on the synchronous movement in space of the emitter and the X-ray cassette during the X-ray shooting process. X-ray diagnostic devices for conventional X-ray T. consist of a movable emitter-X-ray cassette system, a mechanism for moving it, a device for placing the patient, mechanical supports, and electrical and electronic control devices. Tomographs are divided into longitudinal (the selected layer is parallel to the longitudinal axis of the human body), transverse (the selected layer is perpendicular to the axis of the human body) and panoramic (the selected layer has the shape of a curved surface).
Computer X-ray tomography (or computer T.) is based on obtaining a layer-by-layer X-ray image of an organ using a computer. The patient’s body is illuminated with an X-ray around its longitudinal axis, resulting in transverse “slices”. The image of the transverse layer of the object under study on the screen of a grayscale display is provided by mathematical processing of multiple X-ray images of the same transverse layer taken at different angles in the plane of the layer.
Computer examination is usually carried out with the patient lying on his back. There are no contraindications, it is easily tolerated, so it can be performed on an outpatient basis, as well as for seriously ill patients. Makes it possible to examine all parts of the body: head, neck, chest organs, abdominal cavity, spinal cord, mammary glands, spine, bones and joints.
A CT scan of the head is performed after a complete clinical examination of a patient with suspected damage to the central nervous system. In case of traumatic brain injury, fractures of the skull bones, hemorrhages, bruises and swelling of the brain are detected. Using the method, it is possible to detect vascular malformations - aneurysms. For brain tumors, their location is determined, the source of growth and the extent of the tumor are identified.
When examining the chest organs, the mediastinum, great vessels, heart, as well as the lungs and lymph nodes are clearly visible.
When examining the organs of the abdominal cavity and retroperitoneal space, you can obtain an image of the spleen, liver, pancreas and kidneys (the study of the kidneys is more informative with artificial contrast).
Computed tomography is safe and does not cause complications. By supplementing clinical and x-ray data, it allows you to obtain more complete information about the organs.
Radionuclide tomography (single-photon and two-photon) allows you to obtain a layer-by-layer image of the distribution of the radionuclide located in the organ. Indications for radionuclide T. are basically the same as for scintigraphy. However, compared to scintigraphy, radionuclide T. has better resolution. In single-photon radionuclides, medium- and short-lived radionuclides are used (99m Tc, 201 Tl, etc.). It is performed using special gamma cameras with one or two scintillation detectors rotating around the patient.
Two-photon, or positron-emission, T. is performed with ultra-short-lived radionuclides that emit positrons (15 O 2, 18 F, etc.). These radionuclides are produced in charged particle accelerators (cyclotrons) installed directly at the institution. For two-photon radiation, special gamma cameras are used that are capable of recording gamma rays that arise during the annihilation (collision) of a positron with an electron. Two-photon T. is of the greatest scientific interest, however, due to the high cost and complexity of application, its use in medical practice is limited.
Scanning and scintigraphy - designed to obtain images of organs that selectively concentrate the drug. The resulting picture of the distribution and accumulation of the radionuclide gives an idea of the topography, shape and size of the organ, as well as the presence of pathological foci in it.
Ultrasonic tomography - a method of obtaining a layer-by-layer image by analyzing the echo signal reflected from the internal structures of the human body. Layer-by-layer ultrasound images are obtained by scanning an ultrasound beam, and therefore this method is sometimes called ultrasound scanning. Ultrasound T. is a common and accessible type of research, characterized by high information content, cost-effectiveness, and the absence of radiation exposure to the patient.
Magnetic resonance tomography (MRI) - a method of obtaining images of the internal structures of the human body (introscopy) through the use of the phenomenon nuclear magnetic resonance. MRI is most effective in studying the brain, intervertebral discs, and soft tissues. Peter Mansfield and Paul Lauterbur received the Nobel Prize for the invention of MRI in 2003. In the creation of magnetic resonance imaging famous contribution Also contributed by Raymond Damadian, an early researcher of MRI principles, holder of an MRI patent, and creator of the first commercial MRI scanner.
Nuclear magnetic resonance (NMR) - selective absorption of electromagnetic radiation by a substance, caused by the reorientation of the magnetic moments of atomic nuclei located in a constant magnetic field. The NMR phenomenon is the basis for the method of studying the structure and molecular motion in various substances, incl. in biological objects.
Optical coherence tomography (OCT) is a medical imaging method that allows you to obtain images of the near-surface tissues of the human body in vivo with high spatial resolution. Physical principle of operation OCT similar to ultrasonic with the only difference that in OCT To probe biological tissue, optical radiation in the near-infrared (IR) wavelength range is used, rather than acoustic waves. The radiation of the probing beam is focused on the tissue, and the echo delay of the probing radiation reflected from the internal microstructure of the biological tissue at various depths is measured interferometrically. In parallel with depth scanning, a probe beam is scanned across the tissue surface, which provides a transverse scan of the OCT image. The resulting data (OCT image) forms a two-dimensional map of backscattering (or reflection) from microscopic optical inhomogeneities (cellular tissue structures) of biological tissue; Thus, OCT images essentially contain information about the morphological structure of superficial tissues.
OCT is of interest for clinical use for a number of reasons. The resolution of OCT is 10-15 microns, which is 10 times higher than the resolution of other diagnostic methods used in practice and involves studying an object at the level of microscopic tissue architecture. Information about tissue obtained using OCT is intravital, i.e. reflects not only the structure, but also the characteristics of the functional state of tissues. The OCT method is non-invasive because it uses radiation in the near-infrared range with a power of about 5 mW, which does not have a damaging effect on the body. In addition, the OCT method eliminates trauma and does not have the limitations of traditional biopsy.
Positron emission tomography (PAT) - a method of medical imaging (radioisotope diagnostics), based on the use of radiopharmaceuticals (RP) labeled with isotopes - positron emitters, which enter the body of the subjects by injection of an aqueous solution. After emission from the nucleus of an atom, the positron travels a distance of 1-3 mm in the surrounding tissues, losing energy upon collision with other molecules. At the moment of stopping, the positron combines with the electron, annihilation occurs: the mass of both particles turns into energy - two high-energy gamma quanta are emitted, scattering in opposite directions. In a positron emission tomograph, these gamma rays are recorded using several rings of detectors surrounding the patient.
ULTRASOUND DIAGNOSTICS– based on the principle of echolocation: ultrasonic signals reflected from acoustically inhomogeneous structures are converted on the display screen into luminous points that form a spatial two-dimensional image.
It is used to recognize the disease, to monitor the dynamics of the process and evaluate the results of treatment. Due to its safety (the possibility of multiple examinations), ultrasound diagnostics has become widespread.
Usually does not require any special preparation of the patient. The examination of the abdominal organs is mainly carried out in the morning on an empty stomach, the female genital organs, prostate gland and bladder - with a full bladder. For better contact of the ultrasonic sensor with the surface of the body, the skin is lubricated with a special gel.
Ultrasound diagnostics allows you to obtain important information about the condition of various organs - liver, pancreas, spleen, kidneys, bladder, prostate, adrenal glands, thyroid gland, etc. In an obstetric clinic, determine the gestational age and location of the fetus, delays in its development and congenital defects, establish a non-developing pregnancy, complete or incomplete miscarriage.
It is also possible to diagnose gynecological diseases: fibroids and uterine tumors, cysts and ovarian tumors.
Ultrasound examination is indicated in all cases if any formation is palpated in the abdominal cavity; it is of particular importance in recognizing malignant tumors of the digestive organs. Some acute diseases that require urgent surgical intervention are easily diagnosed, such as acute cholecystitis, acute pancreatitis, vascular thrombosis, etc. Sonography almost always allows you to quickly identify the mechanical nature of jaundice and accurately determine its cause.
When examining the heart, information is obtained about the features of its structure and the dynamics of contractions, about congenital and acquired defects, myocardial lesions, coronary artery disease, pericarditis and other diseases of the cardiovascular system. Ultrasound is used to assess pumping function of the heart, to monitor the effect of medications, to study coronary circulation and is the same reliable method of bloodless diagnostics as electrocardiography and x-ray examination of the heart.
Pulse Doppler devices record the speed of blood flow in deep-lying great vessels (aorta, inferior vena cava, renal vessels, etc.), detect obstruction of peripheral vessels - zones of thrombosis or compression, as well as obliterating endarteritis.
Ultrasound diagnostics makes it possible to visually represent the internal structures of the eyeball, even in cases of opacity of its media, allows you to measure the thickness of the lens, the length of the axes of the eye, detect retinal and choroidal detachment, opacification in the vitreous body, and foreign bodies. Used to calculate the optical power of an artificial lens and to monitor the development of myopia.
The ultrasound method is simple and accessible, has no contraindications and can be used repeatedly, even during the day, if the patient’s condition requires it. The information obtained complements the data of computed tomography, X-ray and radioisotope diagnostics, and must be compared with the clinical condition of the patient.
FLUOROGRAPHY– photographing an X-ray image from a screen onto smaller photographic film, carried out using special devices. It is used for mass examinations of the chest organs, mammary glands, paranasal sinuses, etc.
PHONOCARDIOGRAPHY– a method of recording sounds (tones and noises) arising from the activity of the heart and is used to assess its work and recognize disorders, including valve defects.
The phonocardiogram is recorded in a specially equipped isolated room where complete silence can be created. The doctor identifies points on the chest, from which recording is then made using a microphone. The patient's position during recording is horizontal. The use of phonocardiography for dynamic monitoring of the patient’s condition increases the reliability of diagnostic conclusions and makes it possible to evaluate the effectiveness of treatment.
ELECTROCARDIOGRAPHY– registration of electrical phenomena occurring in the heart muscle when it is excited. Their graphic representation is called an electrocardiogram. To record an ECG, electrodes, which are metal plates with sockets for connecting wire plugs, are placed on the limbs and chest.
An electrocardiogram is used to determine the frequency and rhythm of cardiac activity (duration, length, shape of waves and intervals). Some pathological conditions are also analyzed, such as thickening of the walls of one or another part of the heart, heart rhythm disturbances. It is possible to diagnose angina pectoris, coronary disease heart disease, myocardial infarction, myocarditis, pericarditis.
Some medications (cardiac glycosides, diuretics, cordarone, etc.) affect the electrocardiogram readings, which makes it possible to individually select medications for the treatment of the patient.
The advantages of the method - harmlessness and the possibility of application in any conditions - contributed to its widespread introduction into practical medicine.
ELECTROENCEPHALOGRAPHY– a method of electroencephalographic objective study of the functional state of the brain, based on graphic registration of its biopotentials. They are most widely used in solving the following problems: to establish the localization of a pathological focus in the brain, differential diagnosis of diseases of the central nervous system, study the mechanisms of epilepsy and identify it in the early stages; to determine the effectiveness of therapy and assess reversible and irreversible changes in the brain.
While recording electroencephalography, the subject sits reclining in a special comfortable chair or, in severe cases, lies on a couch with a slightly raised headboard. Before the examination, the patient is warned that the recording procedure is harmless, painless, lasts no more than 20-25 minutes, and that it is necessary to close your eyes and relax your muscles. Tests are used with opening and closing the eyes, with irritation by light and sound. Electroencephalogram readings for any disease must be correlated with clinical examination data.
ELECTRO-RADIOGRAPHY– the principle of obtaining an x-ray image on plain paper.
ENDOSCOPIC EXAMINATION METHODS. - Visual examination of hollow organs and body cavities using optical instruments equipped with a lighting device. If necessary, endoscopy is combined with targeted biopsy, as well as X-ray and ultrasound examination. The results obtained from endoscopy can be documented using photography, film and video.
The method is important for the early diagnosis of precancerous diseases and tumors of various localizations in the early stages of their development, as well as for differentiating them from diseases of an inflammatory nature.
Fiber optics has opened up broad prospects for endoscopy. The flexibility of fiber light guides and the ability to transmit images and light along a curved path made the fiberscope flexible and easy to control. This reduced the danger of the study and included the intestines, female genital organs, and blood vessels in the scope of its objects.
Endoscopic methods are also used for medicinal purposes: removal of polyps, local administration of drugs, dissection of cicatricial stenoses, stopping internal bleeding, removal of stones and foreign bodies.
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