B超示0级胎盘表现为()B超示Ⅰ级胎盘表现为()B超示Ⅱ级胎盘表现为() ["A．绒毛膜板不明显","B．绒毛膜板平直","C．绒毛膜板轻度起伏","D．绒毛膜板出现切迹，未达基底膜","E．绒毛膜板出现切迹，达基底膜"]
妊娠32周B超胎盘下缘紧靠子宫颈内口边缘，胎头与膀胱间距离增宽()妊娠28周B超示胎盘与子宫肌层间出现一轮廓不清，边缘不整，无回声区，胎盘增厚并向羊膜腔突出()B超胎盘表面突出圆形肿块，包膜完整，内为多房呈网状或蜂窝状的无回声区或低回声区() ["A．边缘性前置胎盘","B．胎盘血管瘤","C．胎盘早剥","D．葡萄胎","E．正常胎盘声像改变"]
下列哪些因素可以影响心脏排血量() ["A．静脉压","B．静脉回流量","C．心率","D．心脏收缩力","E．交感神经兴奋"]
在治疗急性左心衰竭时，下列哪种药物可以使用() ["A．速尿","B．吗啡","C．安定","D．氨茶碱","E．普萘洛尔(心得安)"]
对于无收缩功能障碍的舒张性心力衰竭的治疗主要措施包括() ["A．β受体阻滞剂","B．钙离子通道阻滞剂","C．维持窦性心律","D．ACEI类药物","E．正性肌力药物"]
胎儿镜下胎血取样时间宜在()
如图，经腹壁羊膜穿刺羊水染色体检查宜在()
