制备雄黄的方法是() ["A.提净法","B.煨法","C.水飞法","D.干馏法","E.烘焙法"]
关于胸外伤引起呼吸困难的机制,错误的是() ["气胸或血胸压迫肺脏","气管或支气管分泌物堵塞","疼痛使胸廓活动受限","肺挫伤引起淤血及水肿","反射性中枢调节作用失常"]
可产生手臂无力和关节疼痛的白指症病因为()。 ["高温","粉尘","噪声","振动","辐射"]
在用于有防火、美观要求时的管道保温,主要采用()做保护层。 ["A、沥青油毡","B、玻璃丝布","C、石棉水泥","D、金属薄板"]
巴豆中遇热活性降低的毒性成分是() ["A.巴豆蛋白","B.巴豆油","C.巴豆酸","D.巴豆苷","E.鞣质"]
矿物质的生理功能有哪些?