牛黄.牛黄为黄牛或水牛的胆囊、胆管或肝管中的结石。宰牛时,如果发现牛的胆囊、胆管及肝管中有硬块,即为牛黄,应立即滤去胆汁,将牛黄取出(迟则为胆汁浸润而变黑)。牛黄取出后应将外部薄膜除净,先裹以灯心草或通草丝,外面再包以白布或毛边纸,置于阴凉处阴干。干燥时切忌风吹、日晒、火烘,以防破裂或变色。本品大多数取于胆囊,形较圆,商品称为胆黄或蛋黄。取于胆管、肝管者呈管状,称为管黄。 Niuhuang. Niuhuang is a stone in the gallbladder, bile duct, or hepatic duct of an ox or buffalo. When slaughtered cattle, if found in the gallbladder, bile duct and hepatic tube in cattle bovine, that is, bezoar, bile should be filtered immediately, remove the bezoar (late bile infiltration and black). After removal of the bezoar, the external film should be removed, first wrapped in rush or straw, outside covered with white cloth or burrs, and dried in the shade. When drying, avoid wind, sun and fire to prevent cracking or discoloration. Most of this product is taken from the gallbladder and has a relatively round shape. The product is called bile yellow or egg yolk. Taken in the bile duct, hepatic tube were tube, known as tube yellow.