小刚同学使用显微镜观察标本时,要使视野中看到的细胞数目最多,应选择的镜头组合为(

题型:选择题

问题:

小刚同学使用显微镜观察标本时,要使视野中看到的细胞数目最多,应选择的镜头组合为(  )

A.③和⑤

B.④和⑥

C.①和④

D.②和⑥

考点:显微镜的构造和使用
题型:选择题

让患者从不同场景、不同角度、与不同人合影的照片中寻找他熟悉的人,属于()

A.物品失认训练方法

B.色彩失认训练方法

C.面容失认训练方法

D.听觉失认训练方法

E.体觉失认训练方法

题型:选择题

阅读理解

     Qian Xuesen is one of the pioneers of China's space science. As a worldfamous expert on aerospace

rockets and aerodynamics,he obtained great achievements in the areas of applied mechanics,engineering

cybernetics and system engineering and made distinguished contributions to the foundation and

development of Chinese aerospace undertaking(事业).

     Graduated from Shanghai Jiaotong University in 1934,Qian Xuesen went to the United States to study

in MIT,Massachusetts Institute of Technology,one year later. After receiving master's degree in MIT,he

went to study in California Institute of Technology and received PhD degrees in both aerospace and

mathematics.

     In 1955,six years after the founding of People's Republic of China,Qian Xuesen returned to his

motherland. His return brought China the hope of developing space science and its own missiles.

     In 1956,Qian Xuesen put forward "Proposal on the Development of China's Aviation Industry for

National Defense". With the support from Zhou Enlai,the premier,and marshal Nie Rongzheng,Qian

Xuesen began to prepare for the establishment of China's first missile and rocket research and

development structure,the Fifth Research Institute of State Ministry of Defense. Henceforth(从此以后),he has long been in charge of the chief technological research and development of China's missile,rocket and

spacecraft.

     Due to research and development led by Qian Xuesen,China successfully exploded its first atom bomb in 1964. Later,China launched its first manmade satellite,Dong Fang Hong I,to the earth orbit on April 24,

1970,becoming the fifth country in the world to independently launch satellite following the former Union of Soviet Socialist Republics,the USA,France and Japan.The satellite floated around the earth,blaring(高声播放) the song Dong Fang Hong,which has the same name as the satellite.

     As a forerunner leading the development of China's aerospace science and technology,Qian Xuesen

also provided chances for young scientists. Wang Yongzhi,former chief designer of China's mannedspace

project,has benefited a lot from Qian Xuesen. "He suggested that rocket of the second generation should

be developed by our second generation scientists. This suggestion gave us chances to be general

designers." Recalling the experience working with Qian Xuesen,Sun Jiadong,general designer of China's

lunar orbiter project,is very grateful. "He put great expectation on us and trusted us a lot. Whenever we

made mistakes,he seldom blamed us,but helped us to find out the reason so we could avoid it in the

future."

     Honored as Father of China's Missile and King of Rockets,Qian Xuesen never stopped his work on

scientific research after he retired. He said he had no time to review the past,but looked forward to the

future.

1. When did Qian xuesen begin to study in Massachusetts Institute of Technology?

A. In 1955.  

B. In 1935.  

C. In 1936.  

D. In 1934.

2. Which of the following is about the five countries that launched manmade satellite independently before 1970?

A. The former Union of Soviet Socialist Republics,the UK,France,China and Japan.

B. The former Union of Soviet Socialist Republics,the USA,Japan,Canada and China.

C. America,France,Japan,China and Australia.

D. The former Union of Soviet Socialist Republics,America,France,Japan and China.

3. What does the underlined word "forerunner"(Paragraph 6) probably mean?

A. A leader.  

B. A pioneer.

C. A competitor.  

D. A successful scientist.

4. According to the passage,which of the following about Qian Xuesen is NOT true?

A. In 1956,he made good preparations for the Fifth Research Institute of State Ministry of Defense.

B. He made outstanding contributions to the establishment and development of Chinese aerospace

undertaking.

C. He returned to China,bringing China the hope of developing space science and its own missiles.

D. He devoted all his life to China's space science.

5. It can be inferred from Paragraph 6 that ________.

A. Qian Xuesen is very concerned about the development of young scientists.

B. The help of Qian Xuesen is beneficial to young scientists.

C. Qian Xuesen gives many opportunities to general designers.

D. When the chief designers do something wrong,Qian Xuesen helps them find out the cause.

题型:选择题
如图为理想变压器原线圈所接交流电压的波形.原、副线圈匝数比n1:n2=10:1,串联在原线圈电路中电流表的示数为1A,下列说法正确的是(  )

A.变压器输出端所接电压表的示数为20V

B.变压器的输出功率为200W

C.变压器输出端的交流电的频率为50Hz

D.穿过变压器铁芯的磁通量变化率的最大值为20/n2Wb/s

题型:选择题

下列哪些是缩窄性心包炎的CT表现().

A.心包不规则增厚,为5~20mm

B.心包增厚呈弥漫性或局限性

C.心包钙化

D.上下腔静脉扩张

E.增强扫描可见扩张的左、右心房,左、右心室呈管状

题型:选择题

50件产品中有4件次品,现从中任取5件,求:

至少有3件次品的取法的概率是多少

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