治疗汞中毒的首选药物为()。
A.依地酸二钠钙
B.青霉胺
C.左旋多巴
D.二乙三胺五乙酸三钠钙
E.二巯基丙磺酸钠
参考答案:E
____ to sunlight for too much time will do harm to one's skin. [ ]
A. Exposed
B. Having exposed
C. Being Exposed
D. After being exposed
台虎钳须保持清洁,要常对()和其它活动表面加油润滑。
A.钳口
B.丝杆
C.手柄
D.钳身