Objective To evaluate the effect and mechanism of non-steroidal anti-flammatory drags(NSAIDs) on the colon cancer cell growth by using S-nitrosoglutathione(GSNO) which can produce nitric oxide.(Methods) Apoptosis of 3 colon cell lines were evaluated by cell growth curve and flow cytometry,the PGE_2 levels in cell culture supernatants were determined by competitive enzyme immunoassay method,and the(protein) expression of COX-1 and COX-2 were analyzed by Western blot.Results The production level of PGE_2 was increased with CSNO treated concentration and time.Using 500?mol/L CSNO treatment for 48h,the expression level of COX-1 and COX-2 protein increased.NASIDs can block the production of PGE_2 but had no effect on the inhibition of cell growth induced by GSNO.Conclusions GSNO can increase PGE_2(production) and induce COX-1 and COX-2 protein expression in a dose-and time-dependent manner.Higher concentrations of GSNO also can inhibite cell growth and induced apoptosis in all 3 cell lines.NSAIDs can block production of PEG2 but NSAIDs are no effect on cell growth.

Objective:To study the application of objective structured clinical examination (OSCE) based on organ system in the practice teaching for clinical interns.Methods:Undergraduate interns majored in clinical medicine in grade 2017 (control group) and 2018 (experimental group) of Jiangjin Central Hospital of Chongqing were selected as the research objects and divided into control group and experimental group. In the control group, the interns received traditional practice teaching, and the interns in the experimental group received traditional bedside teaching combined with OSCE based on organ system. Results of theoretical examination and OSCE test were used to evaluate the teaching effect, and feedbacks were obtained from teachers and students through questionnaire survey and field discussion, so as to compare the differences between the two teaching methods in cultivating clinical ability of medical students.Results:The average scores of theoretical examination of the two groups were similar, the difference was not statistically significant ( P>0.05). In OSCE test, the average scores and total scores of medical history collection station, physical examination station, skill operation station, doctor-patient communication station in the research group were significantly higher than those in the control group ( P<0.05). The average scores of the two groups in the auxiliary examination interpretation station and literature retrieval station were similar, and the differences were not statistically significant ( P>0.05). Conclusion:The OSCE based on organ system is obviously superior to traditional practice teaching in the development of medical students' comprehensive clinical capacity such as medical history collection, physical examination, skill operation and doctor-patient communication.