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问题 单项选择题 A1型题

在病例对照研究中，选择对照的最佳条件是（）

A.对照与病例必须来自同一人群

B.未患所研究疾病的健康人

C.对照可随研究人员随意选择

D.产生病例人群中的非病者，其他非研究因素特征与病例组相同

E.产生病例人群中的非病者，其他非研究因素特征与病例组有可比性

答案

参考答案：E

填空题

16000用科学记数法表示应为______．
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完形填空
从方框内选择适当的选项完成对话。
A. Do you like to go to the movies?          B. It’s wonderful, isn’t it?
C. It doesn’t matter.                      D. Which movie do you like best?
E. Because it makes me feel very excited.     F. Thank you.
G. What kind of movies do you like?
A: Welcome to 9 o’clock Teen Talk. We are talking to Lin Tao, a fourteen-year-old boy. Welcome to the show, Lin Tao.
B: 小题1:        
A: Today, we’re going to talk about the movies. 小题2:       
B: Yes, I do.
A:小题3:        
B: I like Avatar (《阿凡达》) best.
A: 小题4:        
B: Yes, it is the best movie I have ever seen.
A: Why do you think so?
B: 小题5:         
A: By the way, do you like the movie My Father’s Birthday?
B: Yes, very much.
A: Thanks for joining us.
B: That’s OK.
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