Objective To study the iatrogenic risk factors of post-ERCP pancreatitis (PEP).Method A meta-analysis was carried out on 15 clinical studies which included more than 100 patients published in the medical literature in the last twenty years.Result When the risk factors were analysed,OR for endoscopic sphincterotomy (EST) was 3.75 (95％CI 3.01-4.68),OR for papillae precut was 2.17 (95％CI 1.76-2.67),OR for biliary sphincter balloon dilation was 1.66 (95％CI 1.16-2.39),OR for pancreatic contrast injection was 2.79 (2.31-3.37),OR for sphincter of Oddi manome try was 5.86 (95％CI 5.04-6.80),OR for pancreatic stenting was 2.57 (95％CI 2.09-3.17).Conclusion The analysis indicated EST,papillae precut,balloon dilation,pancreatic contrast injection,Oddi manometry,non-prophylactic pancreatic duct stenting were the risk factors of post-ERCP pancreatitis.

Objective To investigate the clinical efficacy of colonoscopic metal stenting and ileus tube catheteriza-tion on left colorectal cancer with acute obstruction. Methods Clinical data of 80 patients meeting the diagnostic criteria for acute obstruction of the left half of colorectal cancer were included in this study. Patients were randomly divided into met-al stent group (n=40) and ileus tube group (n=40). The metal stent group was treated by metal stent and the ileus tube group was treated by ileus tube. Both were carried on by colonoscopy and X-line. After the relief of obstruction ( 7-10 d), patients were underwent colorectal cancer radical resection and anastomosis. The technical operations, improvement of obstruction and the efficacy of surgical treatment were compared between two groups. Results The success rate was 87.5%in metal stent group and the 97.5%in ileus tube group. There was no significant difference in the success rate between two groups (P>0.05). No complications were found in two groups. The operation time and the treatment cost were higher in metal stent group than those in ileus tube group. The relief rates of obstruction were 100%and 95%for metal stent group and ileus tube group, and there was no difference between them. Two cases were operated for emergency because of the failure of obstruc-tion relief. The relief time of obstruction and the difference between C-reactive protein values were much better in metal stent group than those of ileus tube group. After the obstruction relief, patients underwent a radical resection of the tumor and anastomosis, no anastomotic leakage was found in two groups. There were no significant differences in the operation time, in-cision infection and hospitalization time between two groups. Conclusion Anal ileus tube catheterization has a better eco-nomic value in the treatment of acute obstruction, but the efficacy of metal stent is better.

Due to the subjective and objective constraints of universities in China,PBL Teaching Mode failed to gain its popularity in China's medical education.In its teaching reform,Guangzhou Medical University put forward a new teaching model--Web-based PBL Teaching Mode(hereinafter referred to as WPBL).by integrating the classical concept of PBL education with the real situation of the university and carried it out among students in bilingual classes of Clinical Medicine.The resuIts showed that by effectively overcoming the difficulties during the implementation of classical PBL teaching,Web-based PBL Teaching Mode not only succeeded in achieving the teaching objectives,but also improved the learning efficiency and utilization of teaching resources greatly by means of network technology.

Objective To investigate the mechanisms of the alleviation of islet graft earlier injury in the gastric submucosa.Methods The recipients were divided into gastric submucosa group (n =8) and hepatic portal vein group (n =8).1200IEQ SD rat islets were transplanted into diabetic SD rats induced by the administration of streptozocin (STZ).Glucose tolerance test and pathological examination were performed 14 days post transplantation.30 min after the transplantation,the C-peptide of the two groups were detected.12 h after the transplantation,IL-1β and TNF-α of the two groups were examined.Results The mean survival time (MST) of grafts in gastric submucosa group was (25.9 ± 4.1) d and (16.0 ± 0.8) d (P ＜0.01) in portal vein group.The results of glucose tolerance test and immunofluorescent staining demonstrated that grafts in gastric submucosa group survived well and got excellent function 14 days post transplantation.Compared with the gastric submucosa group,after 30 min of the transplantation,C-peptide in portal vein group was significantly higher [(1.46 ± 0.28) ng/ml.vs.(3.84 ± 0.22) ng/ml,P ＜ 0.01].Additionally,the level of IL-1β [(29 ± 1.41) pg/ml.vs.(262.26 ± 53.37) pg/ml,P ＜ 0.01] and TNF-α [(23 ± 1.41) pg/ml.vs.(138.51 ± 39.5) pg/ml,P ＜ 0.01] in portal vein group,were also significantly higher than the gastric submucosa group,after 12 h of the transplantation.Conclusion Islet transplantation in gastric submucosa prolongs islet grafts survival by avoiding or alleviating IBMIR and the injuries induced by early inflammatory mediators.

Objective:Colorectal cancer screening was performed on a general population with age ranging between 40 and 74 years old to evaluate the screening effects of questionnaire survey, fecal occult blood (FOB) test, and colonoscopy, as well as to provide some implications of colorectal cancer screening strategies. Methods: Two-step screening model of questionnaire survey combined with FOB test was applied for the screening. Colonoscopy was conducted in a high-risk population identified through preliminary screening as final diagnosis. Results:Based on the 2,117,304 cases screened, the screening compliance was 39.72%, and 126,118 cases (5.96%) were identified as high risk. Colonoscopies were performed on 25,837 cases, of which 8,095, 1,236, 134, 112, and 336 were identified as adenoma, advanced adenoma, severe dysplasia lesions, early cancer, and advanced cancer, respectively. The early stage di-agnostic rate was 81.52%. Conclusion:The colorectal cancer screening method performed in Tianjin can significantly concentrate on the high-risk population with colorectal cancer, increase the positivity rate of total colonoscopy, and economize medical resources.

Objective:To investigate the pahtogengesis and pathology of delayed xenograft rejection (DXR) after pig to rhesus monkey heart xenotransplantation.Methods:Heterotopic xenogeneic heart transplantation in the abdominal cavity was performed using piglet as donors.4 monkeys were used as recipients.Complete complement depletion was achieve in the recipients treated with repetitive doses of a high activity cobra venom factor (Y CVF).The recipients were immunosuppressed with a combination of cyclosporine A,cyclophosphamide and steroids.Sera were analyzed for C3,C4 levels and complement activity and anti pig endotheliocyte xenoantibody.The graft were examined histopathologically and immunohistochemically for C3,C4,C5b 9,IgM,IgG,necrosis factor alpha (TNF alpha),intercellular adhesion molecule 1 (ICAM 1),CD57 (NK cells),CD68 (macrophages),CD4 and CD8.Results:The xenografts survived 8,10,13,13 days respectively and all grafts occoured DXR.Venular thrombosis was outstanding feature within DXR xenografts,complicated with interstitial edma,local hemorrhage and myocardial necrosis,with mild to moderate cellular infiltration.The serum C3 levels and complement activity almost decreased to 0 from the day of transplantation due to Y CVF,the C4 level began to decrease 2 4 days before the cardic xenografts losing their function.The anti pig endotheliocyte xenoantibody also decreased after transplantation,and slightly increased during DXR,all rejected xenografts showed C3,C4,C5b 9,IgG and IgM deposits in different degree.Large numbers of macrophages (50% of total leukocytes) were found infiltrating the entire xenograft,a few natural killer cells (8%～10%),some of CD4+T cells (15%) and CD8+T cells (25%) were detcted also,up regulation of ICAM 1 on the graft endothelial cells and TNF alpha in the interstitial were demonstrated in the rejected heart.Conclusion:Both Humor and cell mediated immunologic reaction may play an important role in pahtogengesis of DXR. [

Objective To evaluate the feasibility and curative effect of extracorporeal liver perfusion (ECLP) in treatment of acute liver failure (ALF) in pigs. Methods The experiments were carried out in healthy pigs (weight 20-30 kg) under general anesthesia. All of the pigs were randomly divided into 3 groups. ALF model was established by liver blood supply obstructing and portal-systemic shunting. ALF group (n=5): ALF pigs were killed 8 h after establishing. ALF+ECLP group (n=5): ALF pigs were perfused with ECLP for 4 h and killed 8 h after establishing. Normal liver+ECLP group (n=4): normal pigs were dealt with just as ALF+ECLP group. The data of PT, AST, TNF, blood ammonia were collected in all groups. Pathologic changes in liver and brain were detected. Results The levels of PT, AST, TNF, blood ammonia, RBC and HCT in the ALF+ECLP group were lower than those in the ALF group (P

The COVID-19 epidemic has spread to the whole world for three years and has had a serious impact on human life, health and economic activities. China's epidemic prevention and control has gone through the following stages: emergency unconventional stage, emergency normalization stage, and the transitional stage from the emergency normalization to the "Category B infectious disease treated as Category B" normalization, and achieved a major and decisive victory. The designated hospitals for prevention and control of COVID-19 epidemic in Tianjin has successfully completed its tasks in all stages of epidemic prevention and control, and has accumulated valuable experience. This article summarizes the experience of constructing a hospital infection prevention and control system during the "Category B infectious disease treated as Category A" period in designated hospital. The experience is summarized as the "Cluster" hospital infection prevention and control system, namely "three rings" outside, middle and inside, "three districts" of green, orange and red, "three things" before, during and after the event, "two-day pre-purification" and "two-director system", and "one zone" management. In emergency situations, we adopt a simplified version of the cluster hospital infection prevention and control system. In emergency situations, a simplified version of the "Cluster" hospital infection prevention and control system can be adopted. This system has the following characteristics: firstly, the system emphasizes the characteristics of "cluster" and the overall management of key measures to avoid any shortcomings. The second, it emphasizes the transformation of infection control concepts to maximize the safety of medical services through infection control. The third, it emphasizes the optimization of the process. The prevention and control measures should be comprehensive and focused, while also preventing excessive use. The measures emphasize the use of the least resources to achieve the best infection control effect. The fourth, it emphasizes the quality control work of infection control, pays attention to the importance of the process, and advocates the concept of "system slimming, process fattening". Fifthly, it emphasizes that the future development depends on artificial intelligence, in order to improve the quality and efficiency of prevention and control to the greatest extent. Sixth, hospitals need to strengthen continuous training and retraining. We utilize diverse training methods, including artificial intelligence, to ensure that infection control policies and procedures are simple. We have established an evaluation and feedback mechanism to ensure that medical personnel are in an emergency state at all times.