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问题 单项选择题 A型题

高频探头的优点是可提供（）。

A.更高的分辨力

B.增大反射体的频移

C.提高侧向分辨力并且衰减降低

D.增强穿透力

E.聚焦能力增强

答案

参考答案：A

解析：高频探头的波长短，使纵向分辨力提高，但穿透力降低。

阅读理解

根据短文内容，选择最佳答案。

     We go to school at seven thirty. Our classroom is behind the trees. It's very nice. There is a map of

China on the wall. Twenty boys and fifteen girls are in the classroom. There are some flowers on the

teacher's desk. They are for our teachers. We have four classes in the morning and two in the afternoon.

We aren't at school on the weekend.

1. We go to school at              .

A. 7:13                      

B. 7:03                  

C. 7:30

2. Our classroom is               some trees.

A. behind          

B. in                      

C. under

3. A map of China is on the _            .

A. desk            

B. wall                    

C. blackboard

4. The _             are for the teachers.

A. maps            

B. desks                          

C. flowers

5. There are                 students in our ciass.

A. forty-five                  

B. fifteen            

C. thirty-five
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单项选择题 A1型题

糖皮质激素可引起下列病症，但哪一种除外（）

A.精神病

B.降低癫痫阈值

C.高血糖

D.骨质疏松

E.低血钾
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