重大危险源是长期或临时地生产、搬运,使用或储存危险物品,且危险物品的数量等于或者超过 ( )的单元。
A.临界量B.10 tC.极限量D.20 t
参考答案:A
The stranger I rudely quarreled with ____ to be my new boss and it is not hard to imagine what will happen
to me next. [ ]
A. turned out
B. figured out
C. turned to
D. turned over
COPD患者发生肺动脉高压最重要的机制是()
A.肺阻力血管内膜增厚,管腔狭窄
B.血容量扩张
C.红细胞增加致血液黏滞度增加
D.肺小动脉内广泛血栓形成
E.缺氧、C02潴留所致肺小动脉收缩