ACh使窦房结细胞自律性降低是通过()
A.最大复极电位降低
B.阈电位水平下降
C.If电流增强
D.膜对K+通透性增高
E.Ca2+内流增强
参考答案:D
--- What on earth is that noise?
--- Oh, the next flat ___________.
A.was decorated
B.was decorating
C.is being decorated
D.is to be decorated
费用分析的目的不包括( )。
A.费用预算 B.拟订保险费率 C.年终分析 D.费用水平控制