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问题 单项选择题 A1/A2型题

彩超的自相关技术的作用是（）

A.改变二维信号的灰阶对应

B.分析信号相位差，得出血流速度均值和方向

C.放大回波信号的幅度

D.高通滤波，滤去低频信号

E.将回波信号相加

答案

参考答案：B

解析：自相关技术是应用信号与噪声的自相关函数原理，让信号与噪声相互独立，得到血流频移信号的技术。

听力题

根据下列句子及所给单词的首字母，在答题纸上按题号写出各单词的完全形式（每空限填一词）。

小题1:She saved your life at the r_______ of her own. In fact, she almost died.

小题2:Whenever I get into t________, my parents always help me out.

小题3:Mary has a sore throat and she c_______ last night. She should drink some tea with honey.

小题4:She has to put off s________ up a food bank to help the poor.

小题5:The leaves c_______ from green to yellow in autumn.

小题6:We t______ away lots of old things every day.

小题7:The small town has d_________ into a big city in the past ten years.

小题8:I’m too young so Mom always helps me f_______ the clothes.

小题9:Don’t c________ us with other girls. We are different from each other.

小题10:Chinese people aren’t used to k________ and forks when having western food.
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多项选择题

三叉神经痛正确的治疗方法是()

A．首选药物治疗

B．以止痛为目的

C．首选药物为卡马西平

D．也可选用苯妥英钠和氯硝西泮

E．药物治疗无效时可采用神经阻滞或手术治疗
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