正常的潜伏期是指() ["A．从有规律的宫缩到宫颈扩张4cm","B．宫颈平均3～4小时扩张1cm","C．潜伏期约需10小时","D．从有规律宫缩到宫颈扩张9cm","E．从有规律宫缩到宫颈扩张3cm"]
初产妇，妊娠39周，胎儿与母体纵轴相互垂直，孕妇腹前壁可触及胎儿肢体，其胎方位是() ["A．肩左后","B．肩左前","C．肩右后","D．肩右前","E．不能诊断"]
病理缩复环最多见于下列哪种情况() ["A．胎儿畸形","B．子宫收缩乏力","C．头盆不称","D．软产道异常","E．臀位"]
C0弥散进入液体的速度比氧快30倍。()
坐骨结节间7cm，后矢状径7.5cm，足月妊娠，正确的分娩方式为() ["A．自然分娩","B．会阴侧切术","C．胎头吸引术","D．产钳术","E．剖宫产术"]
PaO低于多少可兴奋颈动脉体化学感受器()PaCO超过多少则意识消失()使脑血管扩张达极限的PaCO为()
