在国内,感染性心内膜炎最易发生在()
A.先天性心脏病基础上
B.风湿性心瓣膜病基础上
C.人工心脏瓣膜基础上
D.退行性瓣膜病基础上
E.无基础心脏病上
参考答案:E
The tremendous heat at a star's core, ______ tremendous gravity, joins the nuclei of hydrogen atoms.
A.combined with
B.having combined with
C.combining with
D.being combined to
我国卷烟零售业态的发展变化主要体现在何处?