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问题 单项选择题

下列卵巢癌的CT表现中，不正确的是（）

A.盆腔肿块

B.淋巴转移和血行播散较常见

C.可见腹腔积液

D.常见腹膜腔播散

E.可见大网膜转移

答案

参考答案：B

解析：卵巢癌的延伸包括局部侵犯、腹膜腔的直接种植和淋巴结转移，而血行转移较少见。

单项选择题

电子调速大多利用双向晶闸管的电压导通角的（）来实现。

A.可逆性

B.任意性

C.不可调性

D.可调性
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单项选择题

In science the meaning of the word "explain" suffers with civilization’s every step in search of reality. Science cannot really explain electricity, magnetism, and gravitation; their effects can be measured and predicted, but of their mature no more is known to the modem scientist than to Thales who first speculated on the electrification of amber. Most contemporary physicists reject the notion that man can ever discover what these mysterious forces "really" are. "Electricity," Bertrand Russell says, "is not a thing, like St. Paul’s Cathedral: it is a way in which things behave. When we have told how things behave when they are electrified, we have told all there is to tell." Until recently scientists would have disapproved of such an idea. Aristotle, for example, whose natural science dominated Western thought for two thousand years, believed that man could arrive at an understanding of reality by reasoning from self-evident principles. He felt, for example, that it is a self-evident principle that everything in the universe has its proper place, hence one can deduce that objects fall to the ground because that’s where they belong, and smoke goes up because that’s where it belongs. The goal of Aristotelian science was to explain why things happen. Modem science was born when Galileo began trying to explain how things happen and thus originated the method of controlled experiment which now forms the basis of scientific investigation.

Which of the following principles most influenced scientific thought for two thousand years

A．The speculations of Thales.

B．The forces of electricity, magnetism, and gravity.

C．Aristotle’s natural science.

D．Galileo’s discoveries.
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