胃肠道癌症,目前临床药物治疗尚不满意。现有筛药动物模型及试验方法未能恰当地反映人体癌瘤的情况,使特效药物有可能漏筛。因此,创立新的与人体癌瘤相似的动物肿瘤模型乃当务之急。亚硝胺化合物有较强的致癌作用,可在各种动物的许多器官组织诱发肿瘤,尤其是消化系统肿瘤。甲基亚硝基脲为最有效的致癌物质之一,用单 Gastrointestinal cancer, clinical drug treatment is not yet satisfactory. Existing screening animal models and test methods fail to properly reflect the conditions of human cancers, making it possible for specific drugs to leak through the screen. Therefore, it is imperative to establish a new animal tumor model that is similar to human cancer. Nitrosamine compounds have a strong carcinogenic effect and can induce tumors in many organ tissues of various animals, especially digestive system tumors. Methylnitrosourea is one of the most effective carcinogens, used alone