利用聚合酶链反应扩增特异:DNA手列的重要原因之一是反应体系内存在()
A.DNA聚合酶
B.特异RNA模板
C.特异DNA引物
D.特异RNA引物
E.特异cDNA
参考答案:C
类风湿性关节炎手部关节破坏严重,常出现哪些畸形
A.峰谷畸形
B.尺偏畸形
C.鹅颈畸形
D.扣眼畸形
E.望远镜畸形
A quarrel _____ last Sunday, and he _____ his family. [ ]
A. was broken out; broke away
B. broke out; broke away from
C. was broke out; broke away from
D. broke out; broke away