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问题 单项选择题

某学生在久蹲后突然起立，感到头晕、眼花、耳鸣，继而知觉丧失，引起该现象的机理是（）。

A、神经反射使血管紧张度降低、周围血管广泛扩张

B、植物神经功能失调、血液重新分布能力下降

C、血液因重力作用集聚在下肢使脑部供血下降

D、胸内压和肺内压增加

答案

参考答案：C

选择题

下列属于处理社会关系的实践的是     (　　)

①袁隆平培育超级杂交水稻 ②我国农村正在进行的税费改革

③维护生态平衡           ④青藏铁路的兴建                                                        

A．①②③④

B．②③④

C．③④

D．②
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单项选择题

Anthropology is the study of human beings as creatures of society. It (1) its attention upon those. physical characteristics and industrial techniques, those conventions and values, which (2) one community from all others that belong to a different tradition.

The distinguishing mark of anthropology among the social sciences is that it includes for serious study other societies (3) our own. For its purposes any social (4) of mating and reproduction is as significant as our own. To the anthropologist our customs and those of a New Guinea tribe are two possible social schemes for (5) a common problem, and in so far as he remains an anthropologist he is (6) to avoid any weighting of one (7) the other. He is interested in human behavior, not as it is shaped by one tradition, our own, but as it has been shaped by any tradition (8) He is interested in a wide (9) of custom that is found in various cultures, and his object is to understand the way in which these cultures change and (10) , the different forms through which they express themselves and the (11) in which the customs of any peoples function in the lives of the (12) .

Now custom has not been commonly regarded as a (13) of any great moment. The inner workings of our own brains we feel to be uniquely (14) of investigation, but custom, we have a way of thinking, is behavior at its most commonplace. (15) , it is the other way round. Traditional custom is a mass of detailed behavior more astonishing than (16) any one person can ever evolve in individual actions. Yet that is a rather (17) aspect of the matter. The fact (18) first rate importance is the predominant role that custom (19) in experience and belief, and the very great varieties it may (20)

6（）

A.acknowledged

B.authorized

C.bound

D.credited
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