氟喹诺酮类药物最适用于（）
A.骨关节感染
B.泌尿系感染
C.呼吸道感染
D.皮肤疖肿
E.全身感染
参考答案：B
There are two rooms on the first floor, _____ is used as a guest room .
A．a smaller of which
B．a smaller of them
C．of which the smaller
D．the smaller of them
急性心肌梗死后冠脉再通(再灌注)的最佳时间为起病后( )。
A．1小时内B．3小时内C．6小时内D．12小时内E．24小时内
