前置胎盘孕妇
pregnancy with placenta previa
胎儿和新生儿受前置胎盘的影响
Fetus and newborn affected by placenta praevia
凶险型前置胎盘
pernicious placenta previa
胎盘胎膜残留
Retained placental fragment
retained placenta
CMOS电荷灵敏前置放大器
CMOS charge sensitive preamplifier
Dijkstra最弱前置谓词理论
Dijkstra’s weakest pre-condition theory