消化管壁的组织结构从内向外一般分为：（）四层。
参考答案：粘膜层、粘膜下层、肌层、外膜
Atlanta, as well as many other big cities, _____ once again becoming one of the commercial and
cultural centers of the USA right now. [ ]
A. is
B. are
C. has been
D. have been
脑炎与脑膜炎临床主要区别之一在于前者有（）
A.脑膜刺激征
B.高热
C.脑脊液中白细胞增多，蛋白增高
D.脑实质损害
E.头痛和颅内压增高
