阿糖胞苷的作用方式为 （）
A.直接发挥作用
B.在体内转化为活性的三磷酸阿糖胞苷
C.在体内开环
D.在体内酯化
E.形成酰亚胺结构
参考答案：B
Project management techniques applied to ongoing operations is called as ______ .
A．portfolio management
B．management by projects
C．management by objectives
D．management by exception
杂种优势表现在哪些方面？
