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问题 选择题

科学家发现一种化学式为H3 的氢分子．1mol H3和1mol H2具有相同的（　　）

A．分子数

B．原子数

C．质子数

D．电子数

答案

A．物质的量相同，分子数相同，故A正确；

B.1molH3有3mol原子，1molH2有2mol原子，故B错误；

C．质子数前者有3mol，后者有2mol，故C错误；

D．电子数前者3mol后者2mol，故D错误．

故选A．

阅读理解

阅读理解。

   Many children like collecting stamps. Stamps collecting didn’t begin until 1854. As time goes on, there are more and more kinds of stamps. These stamps are very beautiful and interesting. There are many wonderful pictures on them. And there are more stamp collections. Not only children but also men and women collect stamps. In 1921, American began selling all kinds of stamps to be collectors. In some countries, there are even lessons on stamp-collecting in school. People all over the world are becoming more and more interested in stamps. Each picture on a stamp has its meaning in it. It may be the face of a great leader, a famous scientist or a writer. It may be a beautiful bird or fish. It may be an interesting place. Every stamp tells us a story.

根据短文内容判断正误。正（T），误（F）。

(   ) 1. People began to collect stamps in 1854.

(   ) 2. Only children like collecting stamps.

(   ) 3. Every picture on the stamp has its meaning in it.

(   ) 4. As time goes on more and more people are interested in stamps.

(   ) 5. People can learn something from collecting stamps.
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单项选择题 A3/A4型题

男，24岁，因低热，腹泻3天就诊，腹泻每日3～10次不等，为黄水样或米汤样便，无脓血。大便镜检无特殊发现。

如果是轮状病毒感染，以下哪项检查不能确诊()

A．取粪便作直接或免疫电镜检查，可发现轮状病毒颗粒

B．用酶联免疫吸附试验或免疫酶斑试验检测粪便上清液中的病毒抗原，具有较高的敏感性和特异性

C．从粪便中提取病毒RNA，进行聚丙烯酰胺凝胶电泳和银染色，检查有无轮状病毒的RNA电泳图谱

D．血中可检测出特异性IgM抗体

E．血中可检测出特异性IgG抗体
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