马歇尔试验中,将试件置于的恒温水槽中,对于标准试件保温时间需()
A.20~40min
B.30~40min
C.30~50min
D.40~50min
参考答案:B
连词组句( 请注意句后的标点符号)
1. sister, this, your, is
________________________________________________?
2. is not, your eraser, that
________________________________________________.
3. friends, his, are, those
4. are, brothers, my, these
关于激动药的描述,下列错误的是()
A.有内在活性
B.与受体有亲和力
C.量效曲线呈S型
D.pA2值越大作用越强