[名词解释] 分娩机制

活跃期 T波表示心肌处于何种状态() ["A．极化","B．非极化","C．去极化","D．复极化","E．无电活动"] 生理性缩复环 I导联QRS波群为负波时，电轴() ["A．左偏","B．右偏","C．不偏","D．下偏","E．上偏"] 心房波为哪种() ["A．P波","B．QRS波","C．T波","D．P-R间期","E．U波"] 分娩机制