实验中不应接触管口或瓶口的操作是[ ]
A.将试剂瓶中的液体倒入试管中
D.用胶头滴管向试管内滴加试剂
C.用药匙取用试剂瓶里的粉末状固体
D.用玻璃棒在试剂瓶里蘸取少量液体
答案:B
It's freezing outside. You _______ put on your overcoat. [ ]
A. had better to
B. had better
C. would better
D. would better to
男性,40岁,中上腹饥饿性隐痛反复发作10年,伴反酸、嗳气,进食和服用抑酸剂可缓解。
如进行腹部检查,最具诊断价值的体征是
A.腹肌紧张
B.腹壁柔韧感
C.肠鸣音亢进
D.肝浊音界消失或缩小