维持机体体液平衡的主要器官是（）。 ["皮肤","肺","肾","缓冲系统","肝"]
机械制图中由上向下投影所得的视图，称为（）。 ["主视图","俯视图","左视图","仰视图"]
痔核脱出肛门，需手助方能回纳见于（） ["Ⅰ期内痔","血栓性内痔","血栓性外痔","Ⅲ期内痔","混合痔"]
低钾性碱中毒常出现于下列哪种情况？（） ["挤压创伤","尿毒症","术后少尿","胃肠减压","输血过量"]
排便时出血，痔核无脱出见于（） ["Ⅰ期内痔","血栓性内痔","血栓性外痔","Ⅲ期内痔","混合痔"]
锚具的封闭保护有什么要求？
