晚期髋关节结核的X线表现特征是()
A.股骨头消失
B.病理性后脱位
C.进行性关节间隙变窄
D.边缘型骨质破坏
E.显示肿胀的关节囊
参考答案:A
Miss Li _______ as a secretary for five years in the company, and now she is general manager of it.
A.serves
B.served
C.has served
D.had served
钠冷阱 sodium cold trap