心脏听诊时,主动脉瓣的关闭所引起的振动,标志心室舒张期开始的心音为()。
A.第一心音
B.第二心音
C.第三心音
D.第四心音
E.连续性杂音
参考答案:B
- Shall we play football now?
- Sorry, I can't. Because my mother is ill, I have to ______ her at home.[ ]
A. look for
B. look at
C. look after
D. look like
急性胰腺炎指()
A.血氨升高
B.血清胃泌素升高
C.血清淀粉酶升高
D.胃酸缺乏
E.血清胆红素升高