to establish the human malignant lymphoma model in nude mice, orthotopic transplantation of histologically intact gastric lymphoma tissue from 11 patients was implanted into gastric submucosa of nude mice. Tumorgenicity, invasion, metastasis and morphological characteristics of the transplanted tumors were studied by light microscopy, electronic microscopy, and immunohistochemistry. Two strains screened from 11 cases of human gastric lymphoma were the high metastasis model (HGL HMN 1)and the in situ model of human gastric lymphoma (HGL HMN 2) passaged in vivo for the 36th and 27th generations respectively. 329 nude mice were transplanted. Since the 3rd generation, the tumor transplantation growth rate and the resuscitation rate from liquid nitrogen were 100% .Lymph node metastasis, blood metastasis, and seeding metastasis were present. The transplanted tumors were similar to the original human malignant lymphoma in histopathological, ultrastructure features, DNA content and chromosomal karyatype. Its spontaneous growth occurred in the stomach of the nude mice,accompanied by destructive infiltration of every tissue layer of the stomach wall. Its invasion and metastasis simulated integrally the clinic process of human malignant lymphoma. These models can be used to study the etiology, invasion, metastasis and experimental treatment of human malignant lymphoma.

Objective To evaluate the PDCA cycle on the rehabilitation of postoperative patients with anal fistula, aiming at improving the recovery of patients and preventing recurrence. Methods 144 postoperative patients of anal fistula were randomly divided into the observation group and the control group with 72 cases in each group. The observation group received intervention based upon the PDCA cy-cle, and the control group was given the traditional oral propaganda. The recovery time, recurrence rate, mastering of education content and self-control ability were compared in the two groups using t test and χ2 test. Results The mastering level of education content and the self-management skills in the observation group were superior to those of the control group. After 3 to 24 months of follow-up, the observation group showed shorter recovery time and less recurrence rate than that of the control group. Conclusions Nurs-ing intervention based upon PDCA cycle can strengthen the patients' mastering of related knowledge, pro-mote the recovery, reduce recurrence rate and improve the patients' quality of life.