BACKGROUND:Delayed onset muscle soreness is closely related to skeletal muscle micro-injury, but the exact mechanism of skeletal muscle micro-injury is not yet clear. OBJECTIVE:To observe the histomorphological and ultrastructure changes of skeletal muscle micro-injury models induced by eccentric exercise. METHODS: Forty male Sprague-Dawley rats were randomly divided into quiet control group, immediately after exercise group, post-exercise 24 hours group, post-exercise 48 hours group and post-exercise 72 hours group. In the latter four groups, the rats were subjected to intermittent running on the-16° slope at a speed of 16 m/min: 5 minutes movement, 2 minutes rest and totaly 120 minutes. Rats in the latter four groups were observed immediately, at 24, 48, 72 hours after exercise. RESULTS AND CONCLUSION:After eccentric exercise, the morphology and ultrastructure of rat’s skeletal muscle were both changed to different extents, and Desmin and Vimentin were dyed off for anti-desmin antibody staining at varying degrees. It indicates that one-time eccentric exercise can cause delayed skeletal muscle micro-injury.

Objective:To explore the clinical features of recurrence after choledocholithotomy and to analyze the risk factors.Methods:The clinical data of 730 patients with choledocholithiasis who were treated in our hospital from January 2005 to July 2016 were analyzed retrospectively,550 cases who were received choledocholithotomy were defined as laparotomy group,30 cases with laparoscopic common bile duct exploration (LCBDE) were defined as the LCBDE group,and 150 cases with endoscopic sphincterotomy (EST) were defined as EST group.The recurrence rate of the three groups were compared.The patients of three groups were divided into recurrence group (n=227) and non recurrence group (n=503) according to the recurrent situation,then the clinical features and risk factors of recurrent patients were analyzed by univariate and multivariate Logistic regression analysis.Results:The recurrence rate of EST group was 38.67％,which was significantly higher than that of LCBDE group with 26.67％ and the laparotomy group with 29.27％,and there was statistical difference (P＜0.05).The results of univariate analysis showed that there were statistically significant differences in age,history of HBV infection,jaundice,abnormal total bilirubin,peripapillary diverticulum,biliary infection,biliary stricture,papillary stenosis,sphincter of Oddis dysfunction,history of biliary surgery,cholecystectomy,bile duct diameter ≥ 15 mm,bile duct angle ≤120°,operation type,stone quantity ≥ 2 grains,stone diameter ≥ 10 mm,with or without gallstones (P＜0.05).The results of Logistic multivariate regression analysis showed that age,having peripapillary diverticulum,having history of biliary surgery,bile duct diameter ≥ 15 mm,stone quantity ≥ 2grains and EST operation type were the independent risk factors of the recurrence after choledocholithotomy (P＜0.05).Conclusion:There are many risk factors of recurrence after choledocholithotomy,and operation method should be based on the size and the number of the stones,and the constitution of patients.Preventive measures should be strengthened to control the recurrence after choledocholithotomy.