屏蔽效率分贝数值越大,屏蔽效果越好。
参考答案:对
Mrs. King has ____ China for over three years. [ ]
A. gone to
B. been to
C. come to
D. been in
下列哪几项检查可以诊断急性胃黏膜损害()
A.酶学检查
B.X线检查
C.根据临床表现
D.急诊胃镜检查
E.胃液分析