下颌下腺导管结石X线检查可考虑拍
A．上颌前部颌片B．上颌后部颌片C．下颌颏部颌片D．下颌横断颌片E．咬合翼片
参考答案：D
The passenger was very impolite to the conductor, ____ , of course , made things even worse.
A．who
B．whom
C．which
D．what
下列Ag的McAb能鉴别人的Ts细胞的是（）。
A.CD4
B.CD8
C.CD21
D.CD7
E.CD25
