心房颤动时f波的频率是()
A.150~250次/分
B.260~300次/分
C.100~120次/分
D.350~600次/分
E.>600次/分
参考答案:D
—How did she get infected?
—She _______ the viruses without any protection.
A.exposed to
B.had exposed to
C.was exposed to
D.been exposed to
抑郁症的主要症状不包括()
A."三无"症状
B."三自"症状
C.自杀
D.情绪低落昼重夜轻
E.情绪低落昼轻夜重