心肌不产生完全强直收缩是由于
A.心肌是功能合胞体 B.兴奋传导有房室延搁 C.窦房结对潜在起搏点有抑制作用 D.收缩期较短 E.有效不应期特别长
参考答案:E
What we want is an environmentally friendly car, especially _____ is good on gas. [ ]
A. one
B. one which
C. which
D. one that
与大肠相表里的脏是()
A.心
B.肝
C.肺
D.脾
E.肾