* * 清洁度检查结果为Ⅰ度时，其中的上皮细胞数应在（）
A.-
B.+
C.++
D.+++
E.++++
参考答案：E
I think that something has to be done to stop the air from being polluted, ______ ?
A．doesn't it
B．don’t I
C．don't they
D．haven't they
胸骨左缘第3～4肋间听到舒张早期吹风样杂音的是（）
A.左房室瓣狭窄
B.左房室瓣关闭不全
C.主动脉瓣狭窄
D.主动脉瓣关闭不全
E.肺动脉瓣狭窄
