流体流动的两种型态是()和()。(KHD:工艺基本知识,th=82)
参考答案:层流;湍流
David has grown up. Now he is much ______ than his mother. [ ]
A. tall
B. taller
C. tallest
D. the tallest
下面不属于胰腺外分泌功能试验中的直接实验的是
A.Lundh餐试验B.胰泌素试验C.缩胆素试验D.促胰液素加缩胆囊素试验E.通过静脉直接注射促胰液素