直接导致类风湿性关节炎的致病因子是（）
A.病因不明
B.疱疹病毒
C.支原体
D.细菌
E.病毒
参考答案：A
—How are things going, Janet?
—They have set out to deal with the present situation ________ they think deserves their immediate attention.
A．which
B．where
C．when
D．what
左向右分流型先心病可出现以下症状，但除外（）
A.体循环血量减少
B.肺循环血量增多
C.肺动脉压力增高
D.肺动脉压力下降
E.反复肺炎
