用氟原子置换尿嘧啶5—位上的氢原子,其设计思想是
A. 生物电子等排置换
B. 起生物烷化剂的作用
C. 立体位阻增大
D. 改变药物的理化性质,有利于进入肿瘤细胞
巴比妥类药物的药效主要受下列哪种因素的影响
A. 体内的解离度
B. 水中的溶解度
C. 电子密度分布
D. 官能团
The idea _______ you can do this work well without thinking is quite wrong.
A. that
B. /
C. which
D. of
There was a suggestion _______ Brown should be dropped from the team.
A. that
B. of
C. which
D. what