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　　英语四级仔细阅读一

　　There is evidence that the usual variety of high blood pressure is, in part, a familial disease. Since families have similar genes as well as similar environments, familial diseases could be due to shared genetic influences, to shared environmental factors, or to both. For some years, the role of one

　　environment factor commonly shared by families, namely dietary salt (i.e., sodium chloride), has been studied at Brookhaven National Laboratory. These studies suggest that long excess salt intake can lead to high blood pressure in man and animals. Some individuals, however, and some rats consume large amounts of salt without developing high blood pressure. No matter how strictly all environmental factors were controlled in these experiments, some salt-fed animals never developed hypertension whereas a few rapidly developed very severe hypertension followed by early death. These marked variations were interpreted to result from differences in genetic constitution.

　　By mating long successive generations of those animals that failed to develop hypertension from salt intake, a resistant strain (the " R" strain) has been evolved in which consumption of large quantities of salt fails to influence the blood pressure significantly. In contrast, by mating only animals that quickly develop hypertension from salt, sensitive strain (the "S" strain) has also been developed.

　　The availability of these two strains permits investigations possible. They provide a plausible laboratory model on which to investigate some clinical aspects of the human hypertension. More important, there might be the possibility of developing methods by which genetic susceptibility (敏感性) of human beings to high blood pressure can be defined without waiting for its appearance. Radioactive sodium 22 was an important "tool" in working out the characteristics of the sodium chloride metabolism.

　　21. The study of the effects of salt on high blood pressure was carried out_______.

　　A. as members of the same family tend to use similar amounts of salt

　　B. to explore the long-term use of a sodium based substance

　　C. because it was proven that salt caused high blood pressure

　　D. because of the availability of chemically pure salt and its derivatives

　　22. The main difference between "S" and "R" rats is their_______.

　　A. need for sodium 22 B. rate of mating

　　C. reaction to salt D. type of blood

　　23. We can infer from the article that sodium 22 can be used to_______.

　　A. control high blood pressure

　　B. cure high blood pressure caused by salt

　　C. tell the "S" rats from the "R" rats

　　D. determine what a sodium chloride metabolism is like

　　24. The most beneficial results of the research might be_______.

　　A. development of diets free of salt

　　B. an early cure for high blood pressure

　　C. control of genetic agents that cause high blood pressure

　　D. the early identification of potential high blood pressure victims

　　25. Which of the statements best relates the main idea of this article?

　　A. When salt is added rats and human beings react similarly.

　　B. The near future will see a cure for high blood pressure.

　　C. The medical field is desperately in need of research.

　　D. A tendency toward high blood pressure may be a hereditary factor.

　　参考答案：21. A 22. C 23. D 24. D 25. D

　　英语四级仔细阅读二

　　"Culture shock" occurs as a result of total immersion (浸没) in a new culture. It happens to "people who have been suddenly transplanted abroad. " Newcomers may be anxious because they do not speak the language, know the customs, or understand people's behavior in daily life. The visitor finds that "yes" may not always mean "yes", that friendliness does not necessarily mean friendship, or that statements that appear to be serious are really intended as jokes. The foreigner may be unsure as to when to shake hands, when to start conversations, or how to approach a stranger. The notion of "culture shock" helps explain feelings of bewilderment and disorientation. Language problems do not account for all the frustrations that people feel. When one is deprived of everything that was once so familiar, such as understanding a transportation system, knowing how to register for university classes, or knowing how to make friends, difficulties in coping with the new society may arise.

　　"... when an individual enters a strange culture, he or she is like fish out of water, " Newcomers feel at times that they do not belong to and feel alienated from the native members of the culture. When this happens visitors may want to reject everything about the new environment and may glorify and exaggerate the positive aspects of their own culture. Conversely visitors may scorn their native country by rejecting its values and instead choosing to identify with (if only temporarily) the value of the new country. This may occur as an attempt to over-identify with the new culture in order to be accepted by the people in it.

　　26. The expression "he or she is like fish out of water" suggests_______.

　　A. people away from their cultures can hardly survive in a new culture

　　B. a fish can not survive without water

　　C. people away from their culture experience mental isolation

　　D. people away from their culture have difficulties in their studies

　　27. In order to identify with the new environment, some people may_______.

　　A. give an exaggerated picture of their own country

　　B. criticize the positive aspects of their own country

　　C. abandon their original beliefs

　　D. accept a temporary set of values

　　28. Which of the following statements is TRUE according to the author?

　　A. Homesickness results in culture shock.

　　B. A typical symptom of culture shock is confusion.

　　C. Culture shock is the explanation of anxiety.

　　D. Culture shock happens to foreign students only.

　　29. Newcomers may worry about

　　A. their ignorance of the alien customs

　　B. their knowledge of "yes" in the native language

　　C. their understanding of friendship

　　D. their control of their behavior

　　30. When the foreign visitor is immersed in new problems he finds hard to cope with, he is most likely to feel_______.

　　A. uninsured B. deprived

　　C. alienated D. disappointed

　　26. C 27. B 28. B 29. A 30. C

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