有关限制性内切酶的叙述,正确的是
A.由噬菌体提取而得B.将单链DNA随机切开C.将双链DNA特异切开D.将两个DNA片段连接起来E.催化DNA的甲基化
参考答案:C
—What a nice MP5! Whose is it?
—It's _____. My father bought it for me. [ ]
A. me
B. him
C. his
D. mine
心源性休克宜选用哪种药物()
A.肾上腺素
B.去甲肾上腺素
C.异丙肾上腺素
D.多巴胺
E.麻黄碱