考研英语阅读理解模拟题医学(13)

考研英语阅读理解模拟试题医学(13)
考研英语阅读理解模拟试题：医学（13）
IF YOU ’ RE CONFUSED BY ALL the news about the health effects of eating fish， you’re not alone. On one hand， the omega-3 fatty acids in fish are known to reduce the risk of heart disease， as the American Heart Association reminded us two weeks ago when it restated its recommendation that everybody eat at least two fish servings a week. On the other hand， fish that feed in contaminated waterways contain high levels of mercury， which can lead to cognitive problems in developing brains. That s why’ pregnant women and nursing mothers are advised to limit their consumption.
As if that weren ’t confusing enough，two new studies published last week in the New England Journal of Medicine investigated the possible
effects of mercury on the heart， and they seem to have reached contradictory conclusions. One found no clear link between mercury
levels and heart disease； the other found that men with high levels of mercury in their toenails were more likely to suffer a heart attack than those with low levels. What are we to make of this ？ The first thing to
remember is that this is how science proceeds， by fits and starts and seemingly contradictory results that get resolved only by further study. The second is that not all fish are created equal.
Compared with all the other things you might eat， fish are an excellent source of protein. They tend to eat algae as part of their natural
考研英语阅读理解模拟试题医学(13)
life cycle ， converting it into omega-3 fatty acids that can improve your
cholesterol profile. But it ’also true that our waterways have become
increasingly contaminated with all sorts of pollutants ， including mercury，
and that these pollutants tend to accumulate at different levels in different species. The fish most at risk are predators high in the pelagic food chain，
such as swordfish and sharks（see chart）。

It was to test the effects of mercury on the heart that the two new
studies compared the mercury levels in clippings from toenails ， where
heavy metals tend to be deposited. In one study， researchers led by Dr.
Eliseo Guallar at Johns Hopkins found that European and Israeli men with
the highest mercury levels were nearly 2.2 times as likely to have a heart
attack as those with the lowest levels. The other study， led by Dr.
Walter Willett at the Harvard School of Public Health， looked at a
selection of American men and found no connection between mercury
exposure and risk of heart disease， although Willett told me a “weak association ” cannot be ruled out.
For most of us， eating two servings of fish a week should not pose
any problems. Guallar， who hails from coastal Spain， continues to
flavor his paella with salmon， which has negligible mercury levels.
Willett eats swordfish only about twice a month—— because of its
expense， not any fear of mercury. Fish-oil supplements are high in
omega3 fatty acids and probably don’ t contain as much mercury as whole
fish. But they don’ t taste nearly as good.
注（ 1）：本文选自 Time； 12/9/2002， p99；
注（ 2）：本文习题命题模拟对象2005 真题 Text 1；
1.In the opening paragraph， the author introduces his topic
by [A]making a comparison
[B]justifying an assumption
[C]posing a contrast
[D]explaining a phenomenon
2.The phrase “byfits and starts （”Line 6， Paragraph 2） most probably means _______.
[A]something happens smoothly
[B]something keeps starting and then stopping
again [C]something deserves a lot of effort
[D]something is troublesome
3.Clippings from toenails were chosen for the research most probably because _______.
[A]they are more likely to contain
mercury [B]they influence a person‘s
heart [C]they can be easily obtained
[D]they are connected with the heart
4.The views of Dr. Eliseo Guallar and Dr. Walter Willett are ______.
[A]identical
[B]similar
[C]opposite
[D]complementary
5. What can we infer from the last paragraph？
[A]Fish is no threat to Man.
[B]Do not be frightened by some fish.
[C]Eat Fish-oil supplements instead of fish.
[D]Taste is more important than the safety of the food.答案： CBACB。