Abstract: "The human gastric adcnocarcinoma tissues with or without superficial tissue were subcutancously transplanted into two weeks old ablactation nude micc or three weeks old weaning nude mice, then the formed heterogeneous tumor was excised and the remnant tumor continued to grow subcutancously in nude mice, the differences of the tumor formation rate of the implanted tumor as well as the growing characteristics of remnant tumor in nude mice of different ages, and the effects of tissue selection of human tumor were observed. The tumor formation of implanted tumor is superior in two weeks old to three weeks old mice. In the same period, the tumor formation in 2 weeks old was 4 days before than in 3 weeks old mice, with two times higher in the tu-mor formation rate. Tumor formation rale in group of tumor tissue with capsule was three times higher than that without capsule. The passage rate of the remnant tumor was 100%, and the tumor forming time is only 8 days. It can be concludcd that the tu-mor formation rate of implanted tumor can be improved by using two weeks old mice, it also can be much higher if using tumor tissues with superficial tissue. Tumor formation time can be shortened by using remnant tumor in passage after implanted tumor formed.
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Key words: Nude mice, Implanted tumor, Tumor tissue. Tumor formalion rate