血清前列腺特异抗原测定可用于（）
A.初步判断梗阻程度
B.测量膀胱残余尿量
C.检查内部结构
D.测量前列腺体积
E.排除前列腺癌
参考答案：E
Had Tom studied harder, he ________ the exam.
A．must have got through
B．would have got through
C．would get through
D．could get through
葡萄胎刮宫术后，黄素囊肿消退常需要多长时间（）
A.1～2周
B.4～5周
C.6个月
D.2～4个月
E.8周
