股骨头的主要血液供应来源是
A.旋股内、外侧动脉的分支
B.股圆韧带内的小凹动脉
C.股骨干的滋养动脉升支
D.闭孔动脉
E.阴部内、外动脉
参考答案:A
测定盐酸土霉素的比旋度时,若称取供试品0.5050g,置50ml量瓶中。加盐酸液(9→1000)稀释至刻度,用2dm长的样品管测定,要求比旋度为-188°一-200°。则测得的旋光度的范围应为()
A.-3.80一-4.04
B.-380一-404
C.-1.90——2.02
D.-190——202
E.-1.88——2.00
根据提示用正确的形式完成下列句子。
小题1:The school makes rules (help) us.
小题2:My sister is good at (tell) stories.
小题3:I think one of the (火车) goes to Shanghai.
小题4:Two musicians (want) for the school show.
小题5:Please join our (swim) club.