精制皂苷时,先将粗皂苷溶于甲醇或乙醇,然后加()可使皂苷析出
A.乙醚
B.水
C.正丁醇
D.乙醚-丙酮(1:1)
E.丙酮
参考答案:A, D, E
评价一个12岁半女孩的生长指标,下列哪项是有意义的()
A.身高按年龄×7+70计算
B.检查牙齿发育
C.头围
D.生殖器官发育情况
E.X线摄片,检查成骨
Treatment of frostbite includes().
A.rubbing affected area with ice or snow
B.rubbing affected area briskly to restore circulation
C.wrapping area tightly in warm cloths
D.warming exposed parts rapidly