病原体由传染源体内排出后,侵入另一易感机体在外界环境中所经历的途径称为()
A.传播范围
B.传播途径
C.传播机制
D.传播地域
E.传播链
参考答案:B
Some foreign cartoons for children have been banned on the ________ that they are too violent.
A.proof
B.analysis
C.opinion
D.basis
输卵管妊娠占异位妊娠的:
A.90%左右
B.92%左右
C.95%左右
D.96%左右
E.98%左右