CRH2型动车组无外部电源供电时,回送时间不超过()小时,超过时限速5km/h。A、

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问题:

CRH2型动车组无外部电源供电时,回送时间不超过()小时,超过时限速5km/h。

A、1

B、2

C、3

考点:动车组机械师考试动车组(随车)机械师动车组(随车)机械师题库
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下列排精过程中下述哪几项描述是错误的

A.精子在曲细精管内的转运,通过管周的类肌细胞和睾丸白膜的收缩作用

B.在附睾内转运时,通过其静水压、纤毛运动和附睾管自身蠕动

C.输精管扩张作用

D.附属性腺收缩

E.会阴部及 * * 周围肌肉舒张

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物权公示原则的具体内容包括______。

A.一个特定的标的物上只有一个所有权

B.物权种类法定化

C.物权的公示方法必须由法律规定

D.一个特定的标的物上只有一个所有权

E.物权公示的效力必须由法律规定

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狂犬病的特征是()

A.全身迟缓性瘫痪

B.恐水

C.怕光

D.因肌痉挛

E.肌肉痉挛

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千分尺上应标有()、()、制造厂名及出厂编号。

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Exactly where we will stand in the long war against disease by the year 2050 is impossible to say. (46) But if developments in research maintain their current pace, it seems likely that a combination of improved attention to dietary and environmental factors, along with advances in gene therapy and protein targeted drugs, will have virtually eliminated most major classes of disease.
From an economic standpoint, the best news may be that these accomplishments .could be accompanied by a drop in health-care costs. (47) Costs may even fall as diseases ’are brought under control using pinpointed, short-term therapies now being developed. By 2050 there will be fewer hospitals, and surgical procedures will be largely restricted to the treatment of accidents and other forms of trauma. Spending on nonacute care, both in nursing facilities and in homes, will also fall sharply as more elderly people lead healthy lives until close to death.
One result of medicine’s success in controlling disease will be a dramatic increase in life expectancy. (48) The extent of that increase is a highly speculative matter, but it is worth noting that medical science has already helped to make the very old (currently defined as those over 85 years of age) the fastest growing segment of the population. Between 1960 and 1995, the U.S. population as a whole increased by about 45%, while the segment over 85 years of age grew by almost 300%. (49) There has been a similar explosion in the population of centenarians, with the result that survival to the age of 100 is no longer the newsworthy feat that it was only a few decades ago. U.S. Census Bureau projections already forecast dramatic increase in the number of centenarians in the next 50 years: 4 million in 2050, compared with 37, 000 in 1990.
(50) Although Census Bureau calculations project an increase in average life span of only eight years by the year 2050, some experts believe that the human life span should not begin to encounter any theoretical natural limits before 120. years. With continuing

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