Résumé
The examination of Histology and Embryology was reformed by trying competition-oriented test based on an exam system which is supported by attitude assessment and achievement in learning process.The students welcome the system for its advantages such as the original and various forms,its inspiration of enthusiasm and innovation and its humanism.The system contained processional assessment and final assessment as well.Yet the practiser should increase the rate of written examination to keep the fairness.
Résumé
Objective To observe the differentiation of bone marrow multipotent adult progenitor cells(MAPCs)into skin tissue cells of rats in vivo. Methods Magnetic activated cell sorting (MACS)was used to remove MAPCs from bone marrow of male rats through negative screening.Tail vein injection with combined with MAPCs Was done in C57BL/6 mice with skin wound and nude mice with immunodeficieney.Immunohistochemical staining was used to examine the expression of MHCI antigen in the healed skin of donor SD rats. Results Positive MHCI cells were found in the epidermal fundus and Some hair follicle-like structures of the healed skin of C57BL/6 mice.Hair follicle-like structure appeared in the healed skin of nude mice group,in which positive MHCI cells were found in the basal epidermal and some hair follicle-like structures. Conclusions During skin damage,MAPCs can migrate to the injured skin area and skin adnexa hair foilicle area,transform into epidermal cells and hence participate in the healing of the wound skin.
Résumé
Objective: To observe morphological changes of epithelial-mesenchymal transition in the early stage of mice renal interstitial fibrosis. Methods: Renal interstitial fibrosis was induced by unilateral ureteral obstruction(UUO) in mice. Histological and immunohistochemical methods were used to analyze pathological changes and α-SMA expression in renal tissue.Argentum hexamethylenamine staining and transmission electron microscopy were used to observe changes of the renal tubule basement membrane. Gelatin zymographic analysis was used to observe the expression of MMP2 and MMP9 in renal tissue.Results:The mice suffered from renal interstitial fibrosis were identified by histological analysis and α-SMA positive cells in renal tissue. Argentum hexamethylenamine staining and transmission electron-microscopy showed that the renal tubule basement membrane disrupted locally and renal tubule epithelial cells invaded into the renal interstitium in the early stage of renal interstitial fibrosis. Gelatin zymographic analysis showed that the expression of MMP2 and MMP9 was increased transitorily in the early stage of renal interstitial fibrosis. Conclusion: Renal tubule basement membrane disruption, renal tubule epithelial cells invasion into the renal interstitium, and the expression of MMP2 and MMP9 are involved in the development of renal interstitial fibrosis.
Résumé
The germ cell lineage in the mouse is established during gastrulation;sex determination is achieved after germ cell migrating to the site of the future gonads. Germ cells proliferate indefinitely when cultured in vitro . Human embryonic germ(EG) cells have been recently established;these immortalized EG cells are chromosomally stable and pluripotent, raising the hope that their differentiation can be directed to specific cell types, which may be of value in the clinical treatment of degenerative diseases.