流感病毒肺炎最严重的病理改变是()
A.肺充血、水肿
B.肺透明膜形成
C.肺泡内有纤维蛋白渗出液
D.支气管黏膜坏死脱落
E.黏膜下层灶性出血
参考答案:B
He the job well, but he so careless.
A.had done; had been
B.could do; was
C.could have done; was
D.hadn’t done; had been
用于载人升降机的钢丝绳其安全系数应是:()
A、14
B、10
C、6