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Открытая библиотека для школьников и студентов. Лекции, конспекты и учебные материалы по всем научным направлениям.

Химия Exercise 3. Now read the text about a unique brain operation.
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Exercise 2. Match the terms which will be used in the text (1-6) with their definitions (A-F).

Unit 1. Human Body

Section 1.

Section 3

Section 2

Section 1

Contents

Unit 1. Human body ……………………………………………………………………..…..3

Unit 2. Water ………………………………………………………………………………….6

Unit 3. Fungi …………………………………………………………………………………..9

Unit 4. Bacteria ……………………………………………………………………………….12

Unit 5. Domesticated animals …………………………………………………………..…15

Recommended Report and Presentation Topics ………………………………………18

Unit 6. Brain ………………………………………………………………………….…………19

Unit 7. Sleep …………………………………………………………………………………….22

Unit 8. Coffee …………………………………………………………………………………...25

Unit 9. Human Genetics and Diversity …………………………………………….……….28

Unit 10. Animal adaptations ………………………………………………………….………31

Recommended Report and Presentation Topics …………………………………………34

Unit 11. Human Evolution ………………………………………………….……………….35

Unit 12. Alcohol ……………………………………………………………………………….39

Unit 13. Sex and Gender …………………………………………………………………….43

Unit 14. Aging ………………………………………………………………………...……….47

Unit 15. Food ……………………………………………………………………….………….51

Recommended Report and Presentation Topics ………………………………………..57

Any lover of humanity who looks back on the achievements of medical science must feel his heart glow and his right ventricle expand with the percardiac stimulus of a permissible pride.

Stephen B. Leacock,Canadian economist and humorist

Exercise 1. What do you know about the human body?

1. How is our body prepared for the physical stresses and wear of human life? Speak about each system of organs.

2. What are the most surprising abilities of the human body?

3. What is the adaptive significance of four-chambered heart and greater and lesser circulation?

4. How does the human body adapt to changes?

5. What medical achievements have most significantly changed human life and health care?

1. corpus callosum 2. cerebral hemispheres 3. stroke 4. cerebrospinal fluid 5. seizure[1] 6. congenital A. A pair of structures, originating from the forebrain, that contain the centers concerned with the major senses, voluntary muscle activities, and higher brain functions, such as language and memory. B. Describes phenotypic character or condition recognizable at, and usually before, birth. The term usually refers to hereditary or inborn conditions that are most often harmful. C. A clear watery fluid containing glucose, salts, and a few white blood cells, that is found in the internal cavities and between the surrounding membranes of the central nervous system. It cushions and protects nerve tissues. D. A paroxysmal event due to abnormal, excessive, hypersynchronous discharges from an aggregate of CNS neurons. Epilepsy is diagnosed when there are recurrent numerous events due to a chronic, underlying process. E. A thick band of nerve fibers that connects the two cerebral hemispheres in the brain of placental mammals. It enables coordination of the functions of the two hemispheres. F.A rapidly developing loss of brain function(s) due to disturbance in the blood supply to the brain, caused by a blocked or burst blood vessel.

Strange but True: When Half a Brain Is Better than a Whole One

You might not want to do it, but removing half of your brain will not significantly impact who you are

By Charles Choi

The operation known as hemispherectomy—where half the brain is removed—sounds too radical to ever consider, much less perform. In the last century, however, surgeons have performed it hundreds of times for disorders uncontrollable in any other way. Unbelievably, the surgery has no apparent effect on personality or memory.

The first known hemispherectomy was performed on a dog in 1888 by German physiologist Friedrich Goltz. In humans, neurosurgeon Walter Dandy pioneered the operation at Johns Hopkins University in 1923 on a brain tumor patient. (That man lived for more than three years before ultimately succumbing to cancer.) The procedure is among the most drastic kinds of brain surgery—"You can't take more than half. If you take the whole thing, you've got a problem," Johns Hopkins neurologist John Freeman quips.

One side effect Canadian neurosurgeon Kenneth McKenzie reported in 1938 after a hemispherectomy on a 16-year-old girl who suffered a stroke was that her seizures stopped. Nowadays, the surgery is performed on patients who suffer dozens of seizures every day that resist all medication, and which are due to conditions that mostly affect one hemisphere. "These disorders are often progressive and damage the rest of the brain if not treated," University of California, Los Angeles, neurosurgeon Gary Mathern says. Freeman concurs: "Hemispherectomy is something that one only does when the alternatives are worse."

Anatomical hemispherectomies involve the removal of the entire hemisphere, whereas functional hemispherectomies only take out parts of a hemisphere, as well as severing the corpus callosum, the fiber bundle that connects the two halves of the brain. The evacuated cavity is left empty, filling with cerebrospinal fluid in a day or so. The strength of anatomical hemispherectomies, a specialty of Hopkins, lies in the fact that "leaving even a little bit of brain behind can lead seizures to return," Freeman says. On the other hand, functional hemispherectomies, which U.C.L.A. surgeons usually perform, lead to less blood loss. "Our patients are usually under two years of age, so they have less blood to lose," Mathern says. Most Hopkins hemispherectomy patients are five to 10 years old.

Neurosurgeons have performed the operation on children as young as three months old. Astonishingly, memory and personality develop normally. A recent study found that 86 percent of the 111 children who underwent hemispherectomy at Hopkins between 1975 and 2001 are either seizure-free or have nondisabling seizures that do not require medication. The patients who still suffer seizures usually have congenital defects or developmental abnormalities, where brain damage is often not confined to just one hemisphere, Freeman explains. Another study found that children that underwent hemispherectomies often improved academically once their seizures stopped. "One was champion bowler of her class, one was chess champion of his state, and others are in college doing very nicely," Freeman says.

Of course, the operation has its downside: "You can walk, run—some dance or skip—but you lose use of the hand opposite of the hemisphere that was removed. You have little function in that arm and vision on that side is lost," Freeman says. Remarkably, few other impacts are seen. If the left side of the brain is taken out, "most people have problems with their speech, but it used to be thought that if you took that side out after age two, you'd never talk again, and we've proven that untrue," Freeman says. "The younger a person is when they undergo hemispherectomy, the less disability you have in talking. Where on the right side of the brain speech is transferred to and what it replaces is something nobody has really worked out."

Mathern and his colleagues have recently conducted the first functional magnetic resonance imaging study into hemispherectomy patients, investigating how their brain changes with physical rehabilitation. Probing how the remaining cerebral hemispheres of these patients acquire language, sensory, motor and other functions "could shed a great deal of light on the brain's plasticity, or ability to change," Freeman notes. Still, having half a brain—and therefore only the use of one hand and half a field of vision in each eye—is a condition most would prefer to avoid. (From Scientific American Online, May 24, 2007)

Exercise 4. The words on this list are all verbs (some of them were used in the text). What are the corresponding noun forms? Write them in the second column. The first one has been done for you as an example.

1. to diagnose - diagnosis

2. to examine - _______________

3. to prescribe - ______________

4. to suffer - _________________

5. to operate - _______________

6. to cure - __________________

7. to recover - _______________

8. to analyse - _______________

9. to infect - _________________

10. to carry - ________________

11. to replace - ______________

12. to degenerate - ___________

13. to paralyse - ______________

14. to treat – _________________

15. to affect – ________________

16. to damage - _______________