右室室壁激动和左室室壁激动时间分别为() ["A．0.01～0.02秒，0.02～0.05秒","B．0.01～0.02秒，0.02～0.05秒","C．0.01～0.04秒，0.02～0.06秒","D．0.01～0.05秒，0.02～0.04秒","E．0.01～O.15秒，0.02～0.04秒"]
每两次心跳中一次为正常心跳，一次为异位心跳，称() ["A．奇脉","B．交替脉","C．二联律","D．三联律","E．窦性心律不齐"]
每隔两次正常心跳有一次室性期前收缩时属于() ["A．二联律","B．三联律","C．多源室性期前收缩","D．预激综合征","E．短暂性室性心动过速"]
简述预防产后出血的护理措施
有关预激综合征的叙述中，哪项错误() ["A．心电图特有改变为P-R间期缩短，QRS波起始部有Delta波","B．并发阵发性室上性心动过速时，刺激迷走神经可终止发作","C．禁用异丙肾上腺素","D．QRS波宽小于0.11秒","E．避免使用泮库溴铵"]
简述正常胎盘剥离的表现。
