属于癌前病变的疾病是()
A．单纯性白色角化症
B．白色水肿
C．白色海绵样斑痣
D．白斑
E．白皱病
参考答案：D
Those relatives were________ people. After a few days, I was getting________ and homesick.
A．boring; boring
B．bored; bored
C．bored; boring
D．boring; bored
肝性脑病的发病机制是（）
A.假神经递质
B.氨中毒
C.氨硫醇和短链脂肪酸的协同毒性作用
D.氨基酸代谢不平衡
E.上述多种因素综合作用所致
