甲基硝基亚硝基胍诱发小鼠近端小肠癌的部位探讨

肉眼观察难以确定小鼠十二指肠与空肠界限。近端小肠肿瘤的定位不能单凭肉眼观察其距幽门的远近,或单纯组织学的观察,必须结合离体前解剖学部位。

STUDY ON THE LOCATION OF THE PROXIMAL SMALL INTESTINAL CANCERS IN MICE BY N-METHYL-N'-NITRO-N-NITROSOGUANIDINE

Thirty-three normal adult mice and nine adult mice with proximal small intestinal cancers induced by MNNG were selected for study on the location of these cancers. Slides were stained with HE (part of them stained with PAS) and studied under microscope.The distribution of the duodenal glandswas observed and a middle part was disco-vered between the upper and lower part ofduodenum. The length of the upper part ofduodenum, the middle part and the totallength of the both were measured. The 99%confidence limit of each length was 3.17-2.63, 1.57-0.29, and 3.65-2.95mm respecti-vely. The incidence of the middle part inmice was 42.5% (17/40). The boundarybetween the duodenum and jejunum in micecould not be distinguished by naked eye oreven though on slides under microscope. Sothe location of the proximal small intestinalcancers in these animals should be basedupon the anatomical observation in situ.Among the proximal small intestinal canc-ers of the nine mice. induced by MNNG,four mice had jejunal adenocarcinomas andfive mice had duodenal adenocarcinomas.