使血钙浓度降低的激素是( )
A.PTHK
B.雌激素
C.1,25-(OH)2-D3
D.降钙素
E.胰岛素
参考答案:B,D
()is a method used in Critical Path Methodology for constructing a project schedule network diagram that uses boxes or rectangles, referred to as nodes, to represent activities and connects them with arrows that show the logical relationships that exist between them.
A.PERT
B.AOA
C.WBS
D.PDM