ELISA实验质控图的建立应包括()
A.保存失控情况分析处理记录
B.设定质控图控制限
C.绘制质控图
D.质控图框架的重建
E.设定质控图均值和标准差
参考答案:B, C, D, E
账户印鉴卡应()保管。
A.由会计
B.集中
C.由出纳
D.各自
If we had not been ______ by the traffic jam, we would have arrived an hour earlier.
A.held down
B.held away
C.held on
D.held up