流体在管道内的流动阻力分()阻力和()阻力两种。
参考答案:沿程、局部
_________the thunderstorm ,they_________ the injured man in time. They felt sorry for that.
A.Had it not been for ; could reach
B.If there was not; might have reached
C.But for; might reach
D.If there hadn’t been ; could have reached
患者脘腹疼痛,时作时止,胃脘嘈杂,贪食或有嗜异,面黄肌瘦,或鼻孔作痒,睡中啮齿,此属()
A.虚寒腹痛
B.食积腹痛
C.气滞腹痛
D.蛔虫腹痛