Animal Experimental Model of Human Hepatocellular Carcinoma

土拨鼠饲养和饲养条件的基本问题，如笼子、住房和食物都得到了解决。我们制造了不锈钢室内笼(O。36平方厘米的建筑面积)，这是非常有用的饲养动物观察他们或做实验，但在这个笼子里，他们不交配或繁殖。在较大的室内铁箱（2平方米）中，动物可以繁殖，但新生的幼崽经常被它们的水坝杀死。结果表明，最佳的饲养环境是与野生动物产仔量相同的室外永久性地上笼。我们生产的食物颗粒与豚鼠相同，含有较少的粗纤维。我们成功地建立了一种将病毒注射到非病毒载体幼犬体内获得人工病毒载体的方法。即使是6周大的幼犬，我们也能得到积极的结果。我们的结论是，2-4周大的幼犬最好注射病毒，因为它们睁着眼睛非常活跃，死亡率已经很低。新获得的携带者不会发展成癌症。我们用RIA检测肝炎病毒表面抗原阳性，但我们开发了一种新的聚合酶链反应技术。引物采用编码表面抗原的DNA部分。我们对野生自发性肝癌携带者进行检测，发现当肿瘤体积大于10cm^3时，其发展非常迅速。病毒DNA的整合模式和n-myc重排表明癌症具有多中心性和转移性。C-myc重排非常罕见。

Basical problems about conditions of care and breeding woodchucks such as cages, housing or food were solved. We made stainless steel indoor cages(O. 36cm^2 floor space) which are very useful for keeping animals to observe them or make experiment but in this cage they did not mate or breed. In larger indoor iron boxes(2 m^2) animals could breed but new born pups were often killed by their dams. In our conclusion the best circumstances for breeding is outdoor permanent above ground cages in which litter size same as those of wild animals were obtained. Food pellets we produced are same as those of guinea pigs containing less crude fibers.We succeeded in establishing a method for obtaining artificial virus carriers by injecting virus into non virus carrier pupps. Even in 6 weeks old pupps we could get positive results. We conclude 2-4 weeks old pupps are best to be injected with virus as they are very active with open eyes and mortality is already low. Newly obtained carriers do not still develop cancers. We have checked positivity of hepatitis virus by RIA for surface antigen but we developed new technique utilizing polymerase chain reaction. As primer we used DNA part coding surface antigen.We followed wild spontaneous carriers for detecting hepatic cnacers and found when volume of cancer become larger than 10cm^3 they develop very rapidly. Integration pattern of virus DNA and n-myc rearrangement suggested that cancer develop both multicentric and metastatic. C-myc rearrangement occur very rare.