Some drugs produce bad side___（）

2. There are more than 70 clinically useful antibiotics, Antibiotics fight pathogenic microbes and cancer cells by interfering with their normal cell processes. In most cases, this interference can occur in one of three ways: prevention of cell wall formation, disruption of the cell membrane, and disruption of chemical processes.

3. The contents of bacterial cells are enclosed in a membrane that is surrounded by a rigid wall that prevents the cells from splitting open. Penicillins and some other antibiotics destroy pathogenic microbes by hindering the formation of this wall. Human cells do not have nor need rigid cell walls and so are not damaged by these antibiotics.

4. Some antibiotics, including nystatin, disrupt the cell membrane of certain microbes. This membrane controls the movement of materials in and out of the cell. If the membrane is disrupted, vital nutrients may escape from the cell, or poisonous substances may enter and kill the cell. But the membranes of human cells are not affected because these antibiotics disrupt cell membranes that contain elements found only in microbial cells.

5. All cells produce proteins and nucleic acids, which are vital to the life of any organism. Some antibiotics fight disease by interfering with the chemical processes by which these substances are produced. For example, streptomycin prevent certain kinds of microbes from producing proteins, and rifampin interferes with the formation of nucleic acids. Human cells produce proteins and nucleic acids in much the same way that microbial cells do. But these processes differ enough so that some antibiotics interfere with chemical activities in microbial cells but not in human cells.

A. Autibiotics destroy pathosenic microbes by preventing the formation of the walls surrounding the membranes of the microbial cells that prevent the cells from split- ting open.

B. More than 70 clinically useful antibiotics have been in- vented to fight pathogenic microbes and cancer cells by interacting with their normal cell processes.

C. Human cells are not surrounded by a membrane

D. Some antibiotics disrupt the cell membrane of certain microbes, letting vital nutrients to escape form. the cell or poisonous substances to enter and kill the cell.

E. Nystatin is used to disrupt the wall surrounding the membrane.

F. Some antibiotics fight disease by interfering with chemical activities in microbial cells but not in human cells.

Paragraph 2______。

(判断)AIDS, fifty years ago, didn’t exist.Fifteen years ago a few doctors and public health officials noticed the first cases.Within a few years it was clear that it has now killed almost 14 million people around the world.

Four years ago doctors came up with the first treatment to make a dent in the spiraling death rate.Today that treatment works for some patients, but it’s not clear how long results will last.And still there is no cure.

For the nearly 35 million people around the world now living with HIV, there may never be a cure.Once cells are infected with HIV, it is very difficult — perhaps impossible ―to rid them of the virus.The only sure way to stop AIDS is to prevent infection in the first place, and only a vaccine can do that.

Unfortunately HIV is one of the most changeable viruses known to science.After more than a dozen years, it is still rather difficult to produce effective vaccine.

Still the billions of dollars spent on AIDS research over the past 20 years has not been wasted.As scientists learn more about how HIV survives in the human body, they are realizing that drugs alone may not be enough.To contain the virus effectively, it may take a balance between drug treatments that can keep HIV levels low and a strengthened immune system that can then target and destroy the remaining virus.Until scientists find a vaccine, however, they may control but never cure the century’s final scourge.

46.AIDS didn’t exist fifteen years ago.

47.Scientists have found a vaccine which can prevent HIV infection.

48.Although some treatment works for some patients with HIV, there is still no cure.

49.HIV is a changeable virus so that it is very difficult to produce effective vaccine.

50.We have wasted billions of dollars on AIDS research.

A.accessible

B.access

C.accessibly

D.accession

A.biomedicine

B.herbalism

C.veterinary medicine

D.microbiology

However, the new report disagrees. It was made by the Food and Nutrition Board of the United States National Academy of Sciences. The new report by a team of 15 scientists said there is no evidence to link cholesterol in food directly to heart disease. It noted seven major studies involving people whose diet was changed to include only foods low in cholesterol. The studies found only a very small reduction in the number of heart attacks and there was no reduction in the number of heart attack deaths.

Other studies have shown similar results. They found that a change to low cholesterol foods will have only a minor effect on the amount of cholesterol in a person's blood and only a minor effect on the number of deaths.

Medical scientists hope that two huge new studies may settle the cholesterol dispute. The tests are designed to learn if low cholesterol foods or anti-cholesterol drugs, or both, can reduce the amount of the substance in the blood and reduce the chance of a heart attack. The two new studies will be finished in the next year or two.

The new Academy of Sciences report also discussed other possible links between food and disease. The scientists, in general, they are deeply concerned about some of the recent advice given about food. They noted that a number of private groups, government agencies and several popular books have advised that people can prevent heart disease, cancer and other sicknesses by changing the kinds of foods they eat. The new report said there is often no good scientific evidence to support such advice. In fact, the scientists said such ideas often produce only false hopes or unnecessary fears.

According to the passage, people could reduce the chance of suffering heart attack by ______.

A．eating less foods with a lot of cholesterol

B．eating less of low cholesterol foods

C．eating a lot of high cholesterol foods

D．eating drugs

英译中

We live in a society in which the medicinal and social use of substances (drugs) is pervasive: an aspirin to quiet a headache, some wine to be sociable, coffee to get going in the morning, a cigarette for the nerves.

We live in a society in which the medicinal and social use of substances (drugs) is pervasive: an aspirin to quiet a headache, some wine to be sociable, coffee to get going in the morning, a cigarette for the nerves.(英译中)

A.produce

B.reproduce

C.recover

D.cultivate