调节上升气流与下降气流蓄顶压力差,可以改变加热气体流量。
参考答案:对
A giant of a man was standing in the doorway. His face was almost completely hidden by a long and untidy hair and a wild beard, but you ______ make out his eyes, shining like black beetles under all the hair.
A.might
B.could
C.should
D.would
孕妇,28岁。妊娠38周,规律宫缩6h,入院待产。枕左前位,估计胎儿体重2700g,胎心136/min。 * * 检查:宫口开大3cm,未破膜,S=+1,骨盆外测量未见异常。
此时选择的恰当分娩方式是
A.择期剖宫产B.自然 * * 分娩C.胎头吸引器辅助 * * 分娩D.会阴切开辅助 * * 分娩E.急诊剖宫产术