概要： www.kgf8.com 第三题 阅读理解（10小题，共20分） AFor years, doctors advised their patients that only thing taking multivitamins (复合维生素) does is to give them expensive urine(尿). After all, true vitamin deficien¬cies (shortage) are practically unheard of in industrialized countries. Now it seems those doctors may have been wrong. The result of a growing number of studies suggest that even a modes vit
人教新课标选修七Unit 3单元过关检测题,标签：高二英语同步练习大全,高二学习方法,http://www.kgf8.comwww.kgf8.com
第三题 阅读理解（10小题，共20分）
A
For years, doctors advised their patients that only thing taking multivitamins (复合维生素) does is to give them expensive urine(尿). After all, true vitamin deficien¬cies (shortage) are practically unheard of in industrialized countries. Now it seems those doctors may have been wrong. The result of a growing number of studies suggest that even a modes vitamin shortfall can be harmful to your health. Although proof of the benefits of multivitamins is still far from certain, the few dollars you spend on them is probably a good investment (投资). Or at least that's the argument put for¬ward in the New England Journal of Medicine. Ideally, say Dr. Walter Willett and Dr. Meir Stampfer of Harvard, all vitamin supplements would be evaluated in scientifical¬ly rigorous clinical trials (testing period). But those studies can take a long time and often raise more questions than they answer. At some point, while researchers work on figuring out where the truth lies, it just makes sense to say the potential (潜在的) benefit outweighs the cost.
The best evidence to date concerns foliate, one of the Bvitamins. It's been proved to limit the number of defects in embryos (胚胎), and a recent test found that folate in combination with vitamin B12 and a form of B6 also decreases the reblockage of ar¬teries after surgical repair.
The news on vitamin E has been more mixed. Healthy folks who take 400 inter¬national units daily for at least two years appear somewhat less likely to develop heart disease. But when doctors give vitamin E to patients who already have heart disease, the vitamin doesn't seem to help. It may turn out that vitamin E plays a role in pre¬vention but cannot undo serious damage.
Despite vitamin C's great popularity, consuming large amount (数量) of it still has not been positively linked to any great benefit. The body quickly absorbs(吸收) C and simply excretes (排泄)any excess.
The multivitamins question boils down to this: Do you need to wait until all the evidence is in before you take them, or are you willing to accept that there's enough evidence that they don't hurt and could help?
If the latter there's no need to go to extremes and buy the biggest horse pills or the most expensive bottles. Large doses(剂量) can cause trouble, including excessive (extreme) bleeding and nervous system problems.
Multivitamins are no substitute for exercise and a balanced diet, of course. As long as you understand that any potential benefit is modest and subject to further re¬finement, taking a daily multivitamin makes a lot of sense.
36. At one time doctors discouraged taking multivitamins because they believed that multivitamins _________ .
A. were too expensive for daily consumption
B. were potentially harmful to people's health
C. could not easily be absorbed by the human body
D. could not provide any cure for vitamin deficiencies
37. According to the author, clinical trials of vitamin supplements _________ .
A. often result in misleading conclusions
B. take time and will not produce conclusions
C. appear to be a pure waste of time and resources
D. should be conducted by scientists in some other ways
38. It has been found that vitamin E _________ .
A. can effectively help cure heart disease
B. should be taken by patients regular and directly
C. has a preventive but not curative effect on heart disease
D. should be given to patients with heart disease as early as possible
39. It can be seen that large doses of multivitamins __________ .
A. may cause serious side effects
B. may help prevent excessive bleeding
C. are likely to increase the blockage of arteries
D. are advisable for those with vitamin deficiencies
40. The author concludes the passage with the advice that
A. people benefit more from daily multivitamins than a balanced diet
B. people should expect multivitamins to be used to cure diseases
C. it's risky to take multivitamins without listening to the doctors
D. it's reasonable to take a proper amount of multivitamins daily
B
What do you see from a handful of seeds? Some see green plants, some see blooming flowers, or just seeds. But one group of Shanghai students saw an opportu¬nity to make money.
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