与正常二倍体相比，雌核发育二倍体的成活率并没用明显降低。
panning Tree Protocol calculates path cost based on which of these？（） ["interface bandwidth","interface delay","interface bandwidth and delay","hop count","bridge priority"]
PTN的交换核心是（） ["数据包","SDH帧","ATM信元","PDH帧"]
试述乙脑的诊断。
简述Weight的作用范围。
致畸作用
