50多年来,已知中国南方人包括侨居国外的其鼻咽癌发病率较高,男女两性的发病率在19～24岁以后显著升高。何氏曾提出此病病因系遗传易感性、广泛存在 EB 病毒的早期感染及中国南方人从幼年时即食用传统加工食物,它含有多种挥发性亚硝胺。作者使用了性别、年龄及体重配对的8对动物,4对饲以蒸成鱼和新鲜水,而4对对照 For more than 50 years, Southern Chinese are known to have a high incidence of nasopharyngeal cancer, including expatriates, and the incidence of both sexes has increased significantly after 19 to 24 years of age. He had proposed the etiology of the disease genetic predisposition, the widespread presence of early infection with Epstein-Barr virus and Chinese southerners eat traditional processed foods from childhood, which contains a variety of volatile nitrosamines. The authors used 8 pairs of animals paired with sex, age and weight, 4 pairs fed steamed fish and fresh water, and 4 pairs of controls