双胍类降血糖药的机理是（）
A.抑制胰高血糖的
B.刺激胰岛B细胞
C.增强胰岛素作用
D.促进糖排泄
E.以上均不是
参考答案：E
The boy was______ by all family in his efforts to become a doctor.
A．hoped
B．suggested
C．encouraged
D．agreed
分析比较灌水、滴灌和喷灌区别。
