Artificial triggers It is no secret to nutritionists that some medications can cause weight gain. And for many people without medical education this sometimes comes as a complete surprise. The danger is

Artificial joints With age, a person begins to feel pain and stiffness in the joints of the legs. Most often this happens to the knee joints. If the medications and drugs taken by the patient do not bring a noticeable effect, arthroscopy is indicated - surgical

Artificial mineral waters Currently, the production of artificial mineral water has become quite widespread. This applies primarily to carbon dioxide, nitrogen and hydrogen sulfide samples, which are used mainly as

Artificial sweeteners Research has shown that artificial sweeteners, like sugar, trigger the release of insulin. We already know that this circumstance does not help to lose weight. The more unused insulin in the blood, the more

ARTIFICIAL PLEASURES Artificial products are now widespread, even those that contain nothing nutritious at all. Nature is not familiar with food adulteration, which is why the body does not have its own defense against these products. The sanitary service is also not

Artificial magnets Using modern technological means, man has been able to create artificial permanent magnets, various in shape and purpose. The most widely used are so-called ferrite magnets. They represent

In order to establish the possibility of the body receiving external radiation and quantification Thus, taking into account the risk of developing one or another degree of radiation sickness associated with radiation, radiation dosimetry methods are practiced both in the environment and in relation to an individual.

In conditions of the possibility of being exposed to radiation, in order to ascertain this fact and determine the dose of gamma and X-rays received over a certain period of time, a method of individual photographic control using photographic films is proposed. A person wears a small cassette with sensitive photographic film, which turns black under the influence of radiation. The degree of blackening depends on the radiation dose, increasing with it. By measuring the degree of blackening of the film over a certain time, the dose received can be determined.

Another method of personal monitoring is the use of small portable ionization chambers. Cameras that are pre-charged lose their charge when worn in radiation conditions. Based on the decrease in charge over a certain time, the magnitude of the dose received can be calculated.

The received dose of neutron irradiation is determined by the degree of neutron-induced activity. Under the influence of neutrons, many of their constituent elements are activated in tissues: sodium, phosphorus, chlorine, sulfur, carbon, calcium, etc. The largest dose is generated by sodium and phosphorus radiation.

To determine the dose of neutrons, it is calculated what part of the sodium and phosphorus in the body, the content of which varies little, became active under the influence of neutrons. Determination is carried out by blood and urine. The concentration of sodium and phosphorus is determined in the exact volume of the substrate chemically. The substrate is dried, burned, and the dry residue is applied to the target. Using a beta counter, the degree of activity obtained is determined taking into account the specific activity and the concentration of sodium and phosphorus in the substrate.

A few hours after neutron irradiation, the induced activity is mainly due to sodium, which emits beta particles and gamma rays. With a small half-life of active sodium (15 hours), after just a few hours the value of this isotope decreases, and the activity is mainly due to phosphorus, the half-life of which is 14.3 days.

Since a person irradiated with neutrons becomes a source of gamma radiation, the neutron dose can also be determined from the intensity of such radiation, measured by large counters located around the victim’s body. When assessing the dose received, the time elapsed from irradiation to the study is taken into account, since the degree of induced activity continuously decreases.

After active substances enter the body and are deposited, these substances can be partially excreted in secrets and excreta, where their presence can be determined either by a special chemical method (if these are substances foreign to the body under natural conditions), or by the activity they cause in the biosubstrates under study. Stool and urine are most often examined. Active substances can be alpha, beta and gamma emitters.

Gamma radiation from the human body can be determined by the method used to determine the neutron dose received. The activity of urine and feces is determined after drying and burning the substrate, applying it to a target and measuring it using alpha and beta counters.

One cannot, however, expect accurate and permanent relationship between the content of an incorporated substance in the body and the amount of its excretion.

Some active isotopes can be determined by measuring activity in the blood if these substances, evenly distributed throughout the organs, determine a known relationship between their content in the body and concentration in the blood (sodium, carbon, sulfur).

If active substances or their breakdown products are released in gaseous form through the lungs, their presence can be detected by measuring the specific activity of exhaled air using an ionization chamber connected to a device that measures the ionization current.

Very low activities in preparations can be determined using thick-layer sensitive plates. The drug is applied to the photographic emulsion and after proper exposure and development of the plate in the emulsion, blackened areas are discovered - lines caused by the action of moving active charged particles (tracks).

Alpha particles produce short, thick, straight tracks, while electrons (beta particles) produce thinner, longer and curved tracks. The plates are examined under a microscope at a magnification of 200-600 times.

In the short time since the Second World War, innovations in medicine have embraced almost all branches of medicine, and if a certain doctor recently lamented that almost all medical manuals published before 1945 can now be put aside, he is, to a certain extent, was right. This also applies to the main branch of medicine - internal medicine, which over the past decades has almost completely changed its face. An example of this would be diabetes mellitus.

We have had insulin since 1921. This discovery also belongs to the medical novels. Already in 1869, Langerhans discovered special cells in the pancreas, included in the form of islets in its tissue. Scientists, being unable to prove this, suggested that diabetes mellitus is somehow related to disruption of the pancreas. But twenty years later it was already possible to speak about this with confidence. Researchers Meringa Minkowski removed a dog's pancreas in 1889 to observe future fate operated animal. Some time after surgery, the dog was accidentally placed on a laboratory bench and urinated. They forgot to wipe the table, and when Minkowski’s assistant came to the laboratory the next morning, he saw that the table was covered with white powder. Wanting to find out what he was dealing with, the assistant tasted the powder and discovered that it was sugar.

But how could sugar end up on the table? Naturally, scientists wanted to find out. They remembered that the day before they had conducted an experiment on a dog that behaved indecently. Everything became clear: the pancreas produces a substance that affects sugar metabolism and the use of sugar in the body.

In 1900 the whole problem could have been solved. Then the Russian researcher Sobolev carried out a well-thought-out experiment. The pancreas secretes through the excretory duct into small intestine juice, so important for digestion. Sobolev tied up this duct in the dog, after which the glandular tissue, which had become redundant, shriveled. Despite this, the animal did not develop diabetes. Obviously, the scientist concluded, something was preserved in the gland, and this residue prevented the occurrence of sugar disease. During the autopsy of the animal's corpse, he found Langerhans cells in the gland. They, as one might conclude, are the organ that regulates sugar production in the body. Sobolev's discovery initially remained unknown to the scientific world, since it was described only in Russian literature.

Only twenty years later, Barron brought this work out of oblivion and checked Sobolev’s data, and the surgeon Banting from Toronto (Canada) appreciated its full significance. He followed the path indicated by Sobolev, but he needed a physiologist who would conduct blood sugar studies, and he found an assistant in the person of a young medical student, Best. Banting operated on several dogs and ligated the pancreatic duct. A few weeks later, when the gland had already shriveled, he killed the animals and prepared a paste from the remains of the pancreas, with which he and Best began conducting experiments.

Soon they injected the dog, whose pancreas had been completely removed and who was thereby seemingly doomed to death, some of the juice from this pulp into the cervical artery. And the dog did not die from sugar disease, and a study of its blood showed that immediately after the injection the sugar content in the blood decreased. It became clear that the introduced juice contained a substance that could save patients with diabetes. The only thing now was to extract it in large quantities and inject it into people suffering from diabetes. This juice, or rather the hormone contained in it, was called insulin. Since then, millions of people have been treated with insulin. They were delivered from the immediate danger that threatened them, and their lives were extended.

Approximately thirty years later, another great success was achieved in the treatment of sugar disease: a medicine was found that lowers blood sugar, but unlike insulin, it has the great advantage that it does not need to be injected, but can be taken in tablet form. These drugs belong to the group of sulfonamides, which were discovered by Domagk shortly before the start of the Second World War and turned out to be a miracle cure against all kinds of infections. Subsequently, a number of similar anti-diabetic drugs that can be taken orally have emerged. They contain sulfonylurea and are a valuable addition to the classical treatment of diabetes with diet and insulin.

It goes without saying that, despite new means, we cannot in principle give up either diet or insulin; but a place is still secured for these new medicines; they have proven to be a boon, especially for older people with long-standing diabetes. True, insulin preparations have already been obtained that can be deposited in the patient’s body; it is enough to inject them once a day.

Sugar disease is observed in Lately much more often than before. According to statistics from the therapeutic clinic of the University of Leipzig, the number of patients increased from 2450 to almost 4600. Particularly interesting and important is the question of the dependence of the frequency of this disease on the nutrition of the population and on the economic situation in the country.

Professor Schenk in Starnberg, who dealt with this issue, pointed out, for example, that in Vienna after the war, more precisely in October 1948, it was found that it was not bakers, butchers or waiters in restaurants who most often suffered from diabetes. in favorable nutritional conditions, and academicians, doctors, lawyers and professors. It is, of course, very difficult to accurately determine the number of diabetics in the country. And since diabetes is not a reportable disease, and death certificates often list only the immediate cause of death, accurate statistics are difficult to obtain.

Observations made in Vienna in 1948 are not contradicted by the data of the Swiss physiologist Fleisch, who decided to find out the connection between people's well-being, mental work, village life, on the one hand, and the incidence of diabetes, on the other hand. Fleisch came to the following conclusions: Knowledge workers suffer from diabetes more often than manual workers. Country people develop diabetes less often. In various Swiss cantons and in some areas of Germany - in Bonn and Essen - it was found that in the most affluent sections of the population the number of diabetics is three to four times higher than among workers.

The increase in the number of diabetics is due to the increased average life expectancy, and many people are now reaching an age at which a predisposition to diabetes becomes noticeable and manifests itself. It was precisely the fact that sugar disease can remain hidden for a long time and not manifest itself that prompted the American health service to carry out a widely planned mass survey of the population of individual states; its purpose was to identify cases of hidden diabetes.

As for the large difference in the frequency of diseases among people with physical work, on the one hand, and among people with mental work, on the other hand, it is quite understandable. After all, physical labor is associated with increased energy consumption and thus increased breakdown of sugar.

In the United States, with a then population of 175 million people, about three million diabetics were identified. This big number. During the war, when food was rationed, in Germany it was possible to obtain accurate information about the number of diabetics, since they were counted in the rationing institutions. There were few of them, and people over fifty years of age predominated. The number of young patients (under fifteen years of age) was only 1.5 percent.

Hence the conclusion: nutrition undoubtedly has great value for the development of diabetes.

In recent years, at least in our latitudes, people have consumed relatively few carbohydrates, but much more fat. By the beginning of the 20th century, the ratio of fats to carbohydrates, expressed in calories, was 1:4.5; currently it has increased 1:2. This leads to the fact that now in the West there are many people who are overweight, which, in turn, leads to disruption of the glands internal secretion and, in particular, those associated with energy utilization and consumption. This is of great importance for the onset of diabetes. Treatment of diabetes with insulin, and in our time with sulfonamides, has saved or, in any case, extended the lives of many people, which, of course, should be assessed as a big step forward, but at the same time this is reflected in the overall number of people with diabetes, more or less normal functioning which is supported by medications.

Diabetes in some respects belongs to diseases with uniform inheritance; however, it should be said that only a predisposition is transmitted, while the manifestation, the development of symptoms, is observed in approximately 50 percent of all cases. On the one hand, this is comforting for people whose parents suffered from diabetes; on the other hand, it indicates that it is possible to carry out prophylaxis, prevent the disease, especially in those people who are at risk, and make changes to their lifestyle and nutrition system. Every doctor knows that the task is difficult. After all, people in most cases are not inclined to say “no” to themselves, even if they are convinced of the correctness of the advice that is given.

Sugar disease, being a heavy burden on metabolism, is fraught with great dangers. The largest and sharpest of them is diabetic coma, that is, poisoning by products of incomplete combustion of sugar. Along with this, there are other dangers and complications - from the kidneys, eyes and arteries.

Vascular complications in diabetics have become an important problem. In 20 percent of diabetic cases vascular disorders there is mild damage to the arteries of the brain; in more than a third of cases - diseases of the retina of the eye; in more than half of the cases - exclusively or simultaneously circulatory disorders in the coronary vessels of the heart; in 30 percent of cases - diseases blood vessels lower limbs, often accompanied by gangrene.

So, the problem of sugar disease, as we see, is very extensive. The most important thing is an early diagnosis, and for the patient - reasonable and constantly monitored regulation of metabolism. A diabetic must learn to give up many things and at the same time realize that this is not a refusal of great benefits, true meaning existence. Undoubtedly, thanks to the success of science, it will be possible to solve the problems remaining to us, but for now we should be satisfied with what we currently know about sugar disease and what we have to treat it.

Allergy is undoubtedly one of the most mysterious phenomena in biology and medicine. Not only therapists, but also other specialists are interested in resolving this issue. How to explain this peculiar phenomenon? From eating strawberries, one person develops hives all over his body, while another can eat a whole kilogram of these berries with impunity, and his body does not resist it at all. But this is still a fairly clear, acute and quickly passing case. But there are allergic conditions, such as eczema, in which doctors rack their brains in search of the cause of a long-term illness, and they never manage to solve this riddle. A doctor must sometimes become a skilled detective to find the culprit.

But regardless of the practical need to look for the cause of allergies in each individual case, in order to help the patient, scientists are trying to find out the essence of allergies, to establish what exactly happens in the body during this process.

And here science has new data. Professor

Durr suggested that the occurrence of allergic phenomena is associated with a collision between, for example, a harmful substance contained in strawberries, the so-called allergen, and its opponents, protective substances present in the body this person. This point of view to some extent puts allergies on the same plane as infectious diseases. After all, the concepts of “antigen” and “antibody” relate to the doctrine of infectious diseases and explain some phenomena that are unclear to us. There were many other assumptions and theories, but in the end scientists came to a consensus on the “mechanism” for the occurrence of this immunity.

Due to the collision of a harmful substance - antigen with a protective substance, antibody, which is supposed to be contained and arises in the cell wall, protein molecules change. This leads to the release of biologically active substances of different nature and different effects, for example histamine, bradykinin, serotonin, acetylcholine, heparin and others. In this regard, the tension, tone, and, in fact, the balance of the autonomic nervous system, which maintains a certain level of vital activity of all internal systems of the body, changes. For these reasons, a spasm of smooth muscles occurs (of which, in particular, the bronchi, blood vessels and other internal organs consist), the permeability of small and minute vessels - capillaries - is disrupted, and fluid leaks into the tissue, which leads to edema, the appearance of blisters on the skin (with urticaria) and internal organs. The individual steps of these reactions are visible. Thus, eczema, such a common manifestation of allergies, can be explained by increased permeability of skin cells. The presence of histamine can be determined by its effect on the department gastric juice, the presence of heparin - by the appearance of a special substance, antithrombin, which slows down blood clotting.

As we have already said, the doctor’s task is to identify in each individual case harmful substance, antigen, in order to be able to tell the patient what he must definitely avoid if he wants to get rid of, for example, his eczema. There are many methods for identifying an allergen. The simplest and most common is to apply a suspicious substance to the patient’s skin. At hypersensitivity blisters or characteristic redness and swelling form on it. But with some antigens this is not possible; The skin reaction doesn't help. This happens with some new medicines, and the same applies to food items; they do not cause a skin reaction. Methods have been proposed that make it possible to determine by examining blood plasma which antibodies are formed in it. On this basis, one can judge the nature of the antigens.

There are various methods to prove the presence of antibodies in blood serum. Data obtained from the study of blood groups allowed the use of similar methods. They make it possible to detect antigens found in pollen that cause hay fever, hay asthma and similar conditions. If pollen is brought into contact with the blood serum of people who are allergic to this type of plant, the pollen accumulates in piles.

Now Special attention is given to widespread allergic disease - bronchial asthma. IN early age almost all asthmatics test positive skin tests and most often with house dust or a mixture of house dust and pollen. For asthma that occurs in at a young age, it is easier to find out the cause of the allergy, while for those who get sick late, long-term allergies are also important inflammatory processes in the bronchi, lungs, as well as other factors.

Research various types house dust showed that the most active dust was from mattresses; Dust from carpets and furniture is less important. Bed dust from dwellings in mountainous areas usually does not contain the antigen at all, but it can often be found in bed dust from dwellings in the valleys. This antigen, apparently, is not a protein body, since house dust does not lose its antigen properties even after heating it to 120 degrees. Molds themselves also do not act as an allergic reaction. They may play a role in the formation of antigen in bed dust, since patients with fungal skin diseases are especially sensitive to it. Typical next case: a young man suffered from hay fever since childhood, which appeared in him in the early summer from year to year. Then he gets a fungal infection of the feet and now suffers from hay fever not only at certain times, but all year round. This is often accompanied by asthma, attacks of which are observed only at night and in the early morning hours. They completely disappear with climate change, especially at altitudes above 1500 meters, but immediately appear after returning to low-lying areas.

Allergy sufferers are hypersensitive to penicillin and streptomycin. They experience gastrointestinal disorders after eating food containing substances such as molds, such as cheese, beer, white wine.

Asthmatics react not only to inhaling antigens, substances they do not perceive, but also to ingesting them. At the dermatological clinic of Professor Schuppli in Switzerland, they tried giving honey to people suffering from allergies to pollen. Children with this form of allergy experienced problems with the stomach and intestines. In most cases, such children generally treat honey with disgust. People with allergies to pollen have a positive skin reaction to flower honey. In the search for cures, it was noted that if children under ten years of age were given honey to swallow, it rendered them insensitive. It turned out that this method can be used to treat childhood allergies. For this purpose, adults are injected with extracts from pollen, which also turns out to be useful.

One more thing should be mentioned - photoallergy, hypersensitivity to sunlight. A number of medications have been identified that make the skin more sensitive to light. For example, largactil, often used in psychiatry, has such side effect.

The whole allergy problem is full of interesting details. They are important for all areas of medicine.

Medicine has already, to a certain extent, learned to cope with infectious diseases caused by bacteria using antibiotics, sulfonamides and other drugs. But for diseases caused by viruses, the situation is different, although already at a time when there was no talk of either bacteria or viruses, against one of the most dangerous viral diseases, as it later turned out, namely smallpox, a completely effective protective vaccination.

The recent successful fight against infantile paralysis has shown that diseases of viral origin are not invincible. The study of viruses has led in recent years to a discovery that is destined for a great future. We are talking about interferon.

Let's look at the history of interferon. Back in 1935, the scientist Magrassi, while studying a virus in rabbits that causes a fever in which blisters (herpes) form on the lips, drew attention to one circumstance that seemed strange at first glance. He injected a virus culture into the eyes of rabbits and after a few days detected this virus in the brains of experimental animals. When he injected these rabbits into the brain 4 days later with a culture of a virus that causes fatal inflammation of the brain in one hundred percent of cases, it had no effect on the rabbit with the herpes virus. It seemed to prevent the virus from entering the brain, suppressed its action and thereby protected against illness. So, the suppression of the action of one virus by another during a mixed infection was called virus interference. After 22 years of search and research by scientists from many countries, two Americans, Isaacs and Lindeman, managed to partially uncover this mysterious phenomenon and direct the research towards a practical experiment that could lead to the treatment of human viral diseases. Isaac and Lindeman reported this in the London Medical Journal. These scientists infected chicken embryos with influenza viruses, which multiply in the egg membranes of the embryo. But for the experiment they took not live, but killed, inactivated influenza viruses. These chicken embryos were then infected with live, active viruses, but were unsuccessful. This is observed not only when using influenza viruses and chicken egg membranes. The same phenomenon can be noted with mumps, measles, herpes, and not only when using the egg membranes of a chicken embryo, but also on thyroid tissue, human kidney cells, and so on.

Although the experience reminds us of a protective vaccination, for example, against smallpox, the question as a whole was still very unclear, and both researchers continued their work. They proved that some substance passes into the liquid part of the culture in which cells multiply. It causes the phenomenon of interference, which is why Isaac and Lindeman called it interferon.

After interferon appears in the liquid part of the culture, it can be made to act on other cells; the latter are then protected from the corresponding viral infectious disease.

Interestingly, interferon is not specific. Obtained, for example, with the help of influenza viruses, it acts in the same way against smallpox, but, apparently, it is especially good when used on the same type of animal on which it was obtained.

It can be assumed that the discovery of interferon will be especially valuable for practical medicine. Currently, the question is being raised about the possibility of obtaining interferon in a stronger concentration. If progress is made in this direction, over time it will begin causal treatment viral diseases. It would really be another one a great victory in medicine.

The woman, who had just left the examination table, had been operated on for a tumor six months ago. Now she appeared again, as she again felt unwell, and although the professor at first did not say anything to his assistants about this incident, they knew what was the matter. The patient obviously had a relapse, the resumption of growth of a malignant tumor, which is why she came in.

We will give her a radioactive drug,” the professor told the young doctors; turning to the patient, he added: “This will put you in order again.”

The drug that the professor was talking about, a metal artificially made radioactive, placed in the body of a sick person, emits rays, as is known, capable of destroying cells and, above all, the more sensitive cells of a cancer tumor. Since scientists learned about this, substances artificially made radioactive have played an important role in medicine. But if we want to talk about their essence and structure, we must first talk about isotopes, special substances that once again indicate that modern man is capable of doing a lot.

When Wilhelm Conrad Roentgen discovered the rays that were later named after him in 1895, not only physicists, but the whole world was deeply excited by this revolution, and they immediately began to expect great practical benefits from it.

French physicist Henri Becquerel, in search of highly fluorescent substances, drew attention to potassium uranium compounds, which were much talked about in scientific circles at that time. Radium was not yet known.

And it turned out that potassium uranium compounds, exposed to light, actually emitted rays. At first, scientists thought that these were X-rays, but then it turned out that this was incorrect. Becquerel discovered a special type of rays that can penetrate paper and thin sheet metal and cause blackening of a photographic plate placed behind a sheet of sheet metal. These rays were first called Becquerel rays and then radioactive.

The physicist Pierre Curie also learned about Becquerel’s work and suggested that his young wife Maria, née Skłodowska, study Becquerel’s rays as a topic for her doctoral work. What this advice led to is known: Marie Curie discovered radium and proposed the now accepted name “radioactive radiation” for Becquerel’s rays.

There is no need to tell the novel about it here. It is known to most readers. Marie Curie also discovered other radioactive substances, such as polonium, which she named after her homeland, Poland. This was one of the greatest scientific discoveries. Since that time, thousands of researchers have studied radium, wanting to understand its properties. They found that its radiation weakens extremely slowly and the substance is half consumed only within 1580 years. It was further discovered that in this case a gas is formed, the so-called emanation, which also emits rays, but with a duration of action much shorter than that of radium itself. Finally, it was found that radium radiation was a mixture of three types of rays, which were designated by the first three letters of the Greek alphabet. Alpha rays are positively charged helium nuclei that are ejected last with enormous force; beta rays have great penetrating power, allowing them to pass through wood and thin tin; Gamma rays are endowed with this ability to an even greater extent; they are hard rays and resemble X-rays.

Upon further study of radioactivity, it was established that a chemical element is not something absolutely single, but sometimes consists of several types of atoms. Such elements are called isotopes. They differ from one another not by different special properties, but by different atomic weights. All this would hardly be of interest to doctors if in 1934 the daughter of the great Marie Curie, Irene Curie and her husband Frederic Joliot had not managed to create an artificial radioactive substance. They exposed a piece of aluminum to alpha rays, destroyed the nuclei of aluminum atoms with such bombardment, and obtained an isotope of phosphorus - a substance that does not exist in nature. It was the first artificial radioactive drug. Subsequently, many others were created, and, of course, new and better methods were developed to obtain them. It soon became clear that artificial isotopes should be of great importance for medicine, in particular radioactive phosphorus, radioactive iodine and others. At first, diagnostic studies and physiological observations were meant to study, for example, the metabolic process in the body, the speed of blood flow in the body and in individual organs, especially in the heart, which would make it possible to identify defects in it. The use of artificial radioactive drugs can sometimes be supplemented with X-ray studies.

Artificial radioactive drugs have some properties that X-rays do not have. They require contrast agents, which they cannot penetrate. If a person swallows an iron nail, it is directly visible on the screen and in the picture very clearly. But with a stomach ulcer, the situation is different: the contrast must be created artificially. Therefore, a patient undergoing X-ray examination must drink a suspension of barium sulfate, which absorbs X-rays. Thanks to this, the doctor sees the corresponding changes in the gastric mucosa on the screen and can make a diagnosis.

When using an artificial radioactive drug, the situation is somewhat different. Let us take for example the thyroid gland, which, as is known, is a very complex organ. We know that she voraciously absorbs iodine. Wanting to know the path of iodine in the thyroid gland, we can give a sick person radioactive iodine. This drug disintegrates naturally and emits rays; We, however, are not able to see them, but we can establish their presence, measure them and thereby trace the fate of the injected iodine using special devices. Radioactive iodine is used to destroy a neoplasm (tumor) of the thyroid gland, a malignant goiter. If you give such a patient radioactive iodine, then the latter, greedily absorbed by the thyroid gland, disintegrates within a short time and emits rays into the surrounding tissues, that is, into the cancer cells of the tumor, and these rays, as already mentioned, have destructive power. In this way, you can try to save the patient’s life or, at least, prolong it.

This field of knowledge has grown enormously, and most clinics already have departments for isotope treatment. For many diseases, this is so far the only way that can lead to success. In addition to iodine, a number of other elements are currently used, converted into radioactive ones and providing the necessary effect.

Of course, these must be elements that have some kind of relationship, “affinity,” to the corresponding organs. Such “tendencies”, “affinities”, are often observed. Just as the thyroid gland needs iodine and therefore absorbs it, the bone marrow needs phosphorus. Therefore, in this case, radioactive phosphorus can be used and introduced into the body, since it is greedily absorbed by the bones and bone marrow.

Radioactive gold preparations are of great importance for the treatment of various diseases and, in particular, some malignant tumors. They are used when surgical treatment is impossible or not indicated. But this method of treatment requires a certain amount of caution and supervision on the part of a doctor. Blood and bone marrow can also give an unfavorable reaction, and in case of problems with the liver and kidneys or with more significant circulatory disorders, treatment with radioactive gold is poorly tolerated by patients.

There is another metal, also very suitable for the treatment of malignant neoplasms, if it is artificially made radioactive. This is cobalt. It can be given radioactivity in a nuclear reactor. The radioactivity of cobalt persists for a long time, for several years. In addition, in some cases, treatment with cobalt is more convenient than using x-ray therapy, since cobalt can be injected into various cavities of the body. The greatest value is the treatment of cancer of the female genital organs with cobalt. Radioactive cobalt has the property that its rays are able to penetrate the skin and act on the formations located underneath it, which need to be destroyed or damaged.

There are other isotopes used in medicine. There is no doubt that this chapter is far from over. It will be necessary to find metals and other elements that have special affinities and propensities for certain organs, like the affinity between iodine and the thyroid gland. Then it will be easy to artificially make these elements radioactive and use them to treat a number of diseases.

RADIOACTIVE DRUGS- radioactive substances containing radioactive nuclides, manufactured in various forms and intended for various purposes. In medicine, R. items are used for diagnosing diseases, as well as treating hl. arr. malignant neoplasms.

There are two groups of R. p. - closed and open.

Closed R. p. enclosed in a shell made of non-toxic material (platinum, gold, stainless steel, etc.), which prevents direct contact of the radioactive substance with the environment. In gamma-emitting R. p. the shell functions as a filter for beta radiation (see) and low-energy gamma radiation (see). These drugs are used for application, interstitial and intracavitary radiation therapy (see). The most frequently used are gamma-emitting radiation sources, in which artificial radioactive isotopes of cobalt (60 Co), gold (198 Au), tantalum (182 Ta), cesium (131 Cs), etc. are used as radionuclides. In the past, it was widely used natural radioactive nuclide radium. Preparations of the radioactive isotope California (252 Cf), which is mainly a source of fast neutrons, are also used (see Neutron therapy). Closed R. p. are distinguished by great variety external form. The most widespread are linear refills in the form of needles and tubes (cylinders). Needles are hollow cylinders, one end of which is pointed, and the other has an eyelet for pulling the thread. Pieces of wire (pins) with a diameter, usually less than 1 mm, made of a nickel-cobalt alloy containing radioactive 60Co are placed inside the needle. The length of the pin is called the active length of the R. p. Standard sets include cobalt needles with a pin length from 5 to 50 mm, and a total needle length from 13.5 to 58.5 mm. Tubes (cylinders) differ from needles in that they do not have a pointed end; their active length ranges from 10 to 60 mm. In linear radionuclides, the radionuclide is distributed either uniformly along the entire length—0.0625 μCurie/mm (2.3 MBq/mm)—or unevenly with increased linear activity at the ends. A variety of linear RPs are very small pieces of cobalt, tantalum, or iridium wire (diameter 0.7 mm, length 3 mm), coated with a layer of gold or platinum, which are inserted into nylon hollow threads (tubes). 198Au preparations are also used, in the form of granules with a diameter of 0.8 mm and 2.5 mm long, the surface of which is coated with a layer of platinum. The activity of each granule is about 3.5 microcuries (130 MBq). In addition to linear, closed beads can have a spherical shape with a through hole in the center for threading a thread (radioactive beads).

Sometimes, for surface applications, a dummy is first made from an easily molded material (wax, plastic), repeating the shape of the part of the surface being irradiated. This dummy with closed radioactive elements embedded in it is called a radioactive mask. During interstitial radiation therapy, closed R. items in the form of needles, pins, granules, nylon threads are introduced directly into the tumor tissue using special instruments (see Radiological instruments, Radiosurgery). During intracavitary radiation therapy (see Gamma Therapy), a closed linear-shaped R. p. is inserted into the endostat - a hollow tube previously inserted into the uterus, bladder, rectum, etc.

Open R. p.- radionuclides located in various states of aggregation(true and colloidal solutions, gases, suspensions, absorbable threads and films), which, when used, come into direct contact with organs and tissues, i.e. involved in metabolism and activity individual organs and systems. Open R. p. are used for diagnostic and medicinal purposes. For diagnostics, radionuclide preparations with a short effective half-life (see) are used, which causes an insignificant radiation load on the body. They are characterized by the absence of toxic effects and the presence of beta or gamma radiation, which can be recorded by radiometric methods (see). The most widely used in studying the functions of the kidneys, liver, brain, lungs and other organs, central and peripheral hemodynamics are various compounds labeled with isotopes of technetium (99m Tc), iodine (131 I), indium (111 In, 113m In), as well as gaseous R. p. of xenon (133 Xe), krypton (85 Kr), oxygen (15 O), etc. Administration of R. p., depending on their form, is carried out by oral administration, intravenous administration, inhalation, etc. (see. Radiopharmaceuticals).

With lech. for the purpose, open R. items are most often used in the form of colloidal solutions (see Radioactive colloids). The choice of radionuclide is determined by a short (preferably no more than a few days) half-life, a small effective half-life of the compound, suitable physical properties radiation used and the absence of toxic effects on the body. The radioactive isotopes of yttrium (90 Y), phosphorus (32 P) and gold (198 Au) most fully meet these requirements. Open R. p. are introduced into the tumor tissue by injection using protective syringes (see Beta therapy),

R. items are manufactured industrially and supplied to the hospital. institutions. R. items are kept in special protective rooms - storage facilities, from where they are delivered in transport lead containers to radiomanipulation rooms (see Radiological department). The preparation and dilution of open radioactive substances is carried out in special boxes, fume hoods, and radiomanipulation chambers in order to exclude the possibility of radioactive isotopes getting on the surface of the body or inside the body of medical personnel as a result of contamination of hands, instruments, and inhaled air (see Radiation protection, Radiological protective equipment). technological equipment).

Bibliography: Zedgenidze G. A. and Zubovsky G. A. Clinical radioisotope diagnostics, M., 1968; Pavlov A. S. Interstitial gamma and beta therapy of malignant tumors, M., 1967; Afterloading, 20 years of experience, 1955-1975, ed. by B. Hilaris, N.Y., 1975.

V. S. Datsenko, M. A. Fadeeva.