86 Упражнение 57

А. Объедините отдельные предложения в текст, ис­пользуя различные виды связи, такие как союзы, соединительные слова, например: because, therefore, although, so и др.

Б. Переведите составленный Вами текст.

The brain like other essential organs, depend on a steady oxygen supply.

A steady oxygen supply ensures the brain's continuous function.

The brain's main nutritional substance is glucose.

The brain is very sensitive to changes in the blood glucose level.

If a diabetic receives an overdose of insulin there is a fall in the blood sugar.

If there is a fall in the blood sugar the brain's activity is disturbed.

There is loss of consciousness.

It is important to understand the functions of the different parts of the brain.

It is important in many fields of human activity.

Recent studies of the brain have shown that it divides into two hemispheres.

There are other parts of the brain involved in its overall function.

The right and left hemispheres are most important.

Тексты

для тренировочного и контрольного перевода

(к части 3)

1. Scientists do not understand why dreaming is important, but they think the brain is either cataloging the information it picked up during the day and throwing out data it does not want, or is creating scenarios to work through situations causing emotional stress. Regardless of the reasons, most people who are deprived of sleep or dreams become disoriented, unable to concentrate, and may even have hallucinations.

2. Dr. Marian Annet thinks that a long time ago people used both hands equally; what changed things was that human beings learned to speak. Speech became connected to the left hemisphere of the brain, and as speech became more important, so the left hemisphere became more and more powerful. As the left hemisphere became more important, so the right-hand side of the body was used more; right-handedness became more common, and the functions of the right hemisphere became weaker.

3. Our bodies need calcium for controlling muscle contraction and blood clotting as well as bone formation. But 99% of it is stored in bone, leaving only a tiny bit to circulate in the blood and carry out its other tasks. If the blood calcium level falls too much, the body starts to rob the mineral from the bones. Once that process begins, the loss of bone density can be dramatic and it can happen at any age. Women who go on unbalanced or starvation diets are particularly vulnerable. The best way to take calcium is in food because, when combined with other nutrients, it is much easier to absorb.

4. Why does blood remain in a fluid state when in the vascular system and why does clot within a few minutes when it is shed? It is obvious that the clotting in the blood vessels would produce serious symptoms which might be fatal in some instances, for arteries and veins would be obstructed, thereby preventing the proper flow of blood to the various tissues of the body. On the other hand, if the blood did not clot promptly, as in persons with hemophilia, death might result from an extensive hemorrhage.

5. When blood passes through the capillaries, it loses some of its plasma, which becomes part of a liquid that is between the cells. This liquid is known as lymph. Lymph needs to be returned to the circulatory system to keep the blood volume fairly constant, so a system of tubes called the lymphatic system drains the lymph back into the blood. Along the way, lymph passes through lymph nodes that filter out any debris, including bacteria, from the lymph. Lymph nodes are made from lymphoid tissue, but they are not the only organs where lymphoid tissue is found; it is found everywhere that bacteria or other germs can easily invade the body, specifically in the linings of the parts of the body that are exposed to the outside.

6. About the year 1900 Dr. Mackenzie in England observed that the prevailing system of diagnosis of heart disease failed too often to give an accurate estimate as to the future life of the patient. From his studies there developed a new attitude towardthe study of the heart. The interest in heart disease was broadened

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to include not only organic changes but also the functional conditions of the valves and the heart muscle. Dr. Mackenzie first demonstrated that certain irregularities such as respiratory arrhythmia and extrasystoles, are of practically no significance while others such as auricular fibrillation and paroxysmal tachycardia, may be much more serious. So we now speak of both structural or organic pathology and of functional pathology. Both are important. More recently doctors came to realize that a third factor is equally important, namely the etiology or the thing which caused the heart trouble.

7. In the 19th century physicians usually had to wait until an autopsy had been performed on a patient before they could determine whether or not their diagnosis had been correct. In the past, diagnosis has been static and qualitative. The present trend is towards dynamic and quantitative diagnosis: how far has the trouble advanced, and what progress is it likely to make? The current emphasis on early recognition of diseases that cause few symptoms until they reach a dangerous stage is bringing various "special" investigations into routine practice. But as a rule patients are subjected to X-rays, blood tests and the rest only when the possible diagnoses have been reduced to two or three suspects, or when a provisional diagnosis needs elaboration.

8. It has long been believed that the cyclic changes observed in plants and animals were totally in response to environmental changes and, as such, were exogenous or of external origin. This hypothesis is now being rejected by some chronobiologists who hold that the biological rhythms are intrinsic to the organisms and that the organisms possess their own physiological mechanism for keeping time. The mechanism has been called the "biological clock". An example of adjustment of the biological clock in humans is recovery from "jet lag". This phenomenon occurs when humans are transported by jet plane across time zones. It is characterized by fatigue and lowered efficiency, which persist until the "biological clock" adjusts to the new environmental cycle.