With the implement of inverted burden of proof,the work of clinical practice and teaching faces challenge. At present, more aspects of clinical medicine and practice teaching are not suitable for the new rule, and they have affected and restricted the improvement of quality of clinical practice teaching. It is necessary for interns and clinical tutors to study the new rule and suit its demands. Only in this way can the quality of clinical medicine, teaching and practice be improved.

Objective To investigate the protective effect of heme oxygenase-1 for xeno-heart transplantation and the possible mechanism.Methods Cobalt protoporphyrin (CoPP), HO-1 inducer, and zinc protoporphyrin (ZnPP), HO-1 inhibitor, were used to intervene donors and recipients on the model of NIH-Wistar cardiac transplants respectively and simultaneously some of recipients were treated with immunesuppressor cyclosporine A (CsA), and control group and CsA treated group were set up respectively. The expression of HO-1 protein, HO-1 mRNA, caspase-3 and STAT-3 in transplanted heart tissue was detected by immunohistochemistry, RT-PCR and Western Blot. At the same time, HO-1 enzymatic activity was examined in heart tissue, and the cardiac cell apoptosis was examined by means of TUNEL. The differences among various factors were compared.Results The survival time of cardiac transplants in CoPP group was longer than that in control and ZnPP groups (P

Objective To explore the mechanism of delayed xenograft rejection(DXR) by dynamic observation of histological and immunohistologic changes in mouse-to-rat cardiac xenografts.Methods A model of mouse-to-rat cardiac heterotopic xenotransplantation in neck was established by cuff technique.NIH mouse hearts not transplanted served as controls(n=4).Some xenograft recipients were killed and cardiac xenografts harvested at end of 3,8,16,24 h(n=4 for each time point) after transplantation.The cardiac hearts(n=16) of some xenograft recipients were not harvested until rejection time to determine their survival time.All heart samples were examined by HE and immunohistochemistry for semi-quantitative determination of antibodies including C3,IgM,IgG,E-selectin and macrophage marker——CD68.Results During the period after transplantation,the degree of rejection of xenografts became more and more serious till ultimate rejection.The mean survival time of the xenografts was(49.3?16.2) h.Immunohistochemical examination showed C3 were not detected in the xenografts at any time during the course of rejection;From 3 h after transplantation,obvious deposition of IgM was found in the grafts and IgG deposition got abundant;E-selectin expression was found as early as 3 h after transplantation and increased gradually;There was progressive infiltration by macrophages in the grafts.Conclusion Mouse-to-rat cardiac xenotransplantation can serve as an animal model of DXR.Endothelial cells activation,IgM and IgG,macrophage infiltration involve in DXR development except C3.

Objective To investigate the predictive value of plasma lipoprotein associated phospholipase A 2 (Lp-PLA2 ) in cere-bral infarction(CI) after transient cerebral ischemia attack (TIA).Methods Plasma Lp-PLA2 level was detected in 112 TIA pa-tients ,and the incidence rate of CI was observed on 7 ,30 ,90 d after TIA.Then the grouping was performed according to the Lp-PLA2 level ,and the predictive value of Lp-PLA2 in the risk of CI occurrence after TIA was evaluated.Results Among 112 patients with TIA ,27 cases (24.1% ) developed CI within 90 d;there were 17 cases(63.0% ) of CI after TIA in the Lp-PLA2 >207 μg/L group ,which were significantly higher than that in the 175-207 μg/L group and <175 μg/L group (P<0.05);moreover the CI occurrence in TIA patients was mainly concentrated within 7 d after onset ;the patients of Lp-PLA2 ≥175μg/L were mainly distrib-uted in the moderate and high risk groups of ABCD2 score system ;in ROC curve of Lp-PLA2 for predicting CI after TIA ,with Lp-PLA2 ≥194 μg/L as the diagnostic critical point ,the sensitivity was 0.730 and specificity was 0.680.Conclusion Lp-PLA2 may be an effective risk predictive indicator of CI occurrence after TIA ,and can improve the adverse outcome of TIA patients.

Objective To investigate the alteration of aquaporin 1(AQP1) expression in lung tissues in hemorrhage-lipopolysaccharide(LPS) two-hits rats and the effects of panaxadiols(PDS)and dexamthasone(Dex) on it.Methods The rat model of acute lung injury was built with hemorrhage-LPS two hits.The experiment was divided into control group(S),two-hits model group(HL),DEX group(HLD),and PDS group(HLP).The pathological changes of lung tissue were examined by HE staining.The expression of AQP1 was analyzed by RT-PCR,Western blotting and immunohistochemical staining.Results ① Significant inflammatory changes in pulmonary interstitial of rats in HL group were observed.However,in HLD group and HLP group,the pulmonary pathologic changes were much slighter.② AQP1 mRNA and protein expressions in lung tissues in HL group were significantly decreased compared with others groups(P