献血者的献血记录不包括:() ["个人资料","体检.病史","献血次数","用血单位"]
堤防滑坡易在堤脚处或其附近有()现象。 ["凹陷","沉陷","隆起","变陡"]
生产性毒物进入机体最主要途径是()、 ["A、皮肤","B、消化道","C、呼吸道","D、口腔粘膜","E、眼结膜"]
频道变换方式() ["只有射频直接变换方式","只有中频变换方式","有射频直接变换和中频变换两种方式","有无数种方式"]
构件产生过大变形将意味着其失去了()能力。 ["承载","承压","塑性","弹性"]
如何判断母牛是否发情?