某特定时间内的总人口中，患有某病的病例所占的比例称为（）. A

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问题单项选择题

某特定时间内的总人口中，患有某病的病例所占的比例称为（）.

A．发病率

B．患病率

C．保护率

D．接种后反应率

E．发病密度

答案

参考答案：B

解析：

患病率是指某特定时间内总人口中某病新旧病例所占比例。

填空题

根据短文内容和首字母提示,在下文空格处填入适当的词使短文完整.(每空一词)。

My mother had an accident last Thursday. She was trapped in her c 1 for 20 minutes!

It was a cold day. And the s 2 was heavy. She was driving home f 3 work at nine p.m. As there

was snow on the road. She drove very slowly. But u 4 , the car broke down suddenly. She

couldn't s 5 it. And what was worse, she couldn't open the door. She f 6 very helpless and didn't

know what to do. So she telephoned my father with her mobile. But my father happened to(碰巧) be

in a 7 city. There were f 8 people on the road and the snow c 9 to fall around her car. She had

to call 110 for help. Two policemen arrived in a h 10 . They tried many ways to open the door. And

my mother came back home in their police car in the end. She gave us a surprise!.

判断题

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