分离血清CIC的PEG相对分子量是() ["A．24000","B．12000","C．6000","D．3000","E．1000"]
补体蛋白约占人体血清总蛋白的() ["A．2%","B．5%","C．10%","D．15%","E．25%"]
关于补体的理化特点，下列不正确的是() ["A．补体的性质不稳定","B．不受各种理化因素的影响","C．在0～10℃条件下活性只能保持3～4天","D．加热56℃30min灭活","E．标本保存应置于-20℃以下"]
避免铸件出现跑火的现象，应注意哪些问题?
补体活化的旁路途径的激活物，下列物质应除外的是() ["A．细菌内毒素","B．酵母多糖","C．葡聚糖","D．凝聚的IgA","E．甘露聚糖"]
防止铸件脆断，可采取哪些措施?
