Streptolysin S (SLS),one of the important virulence factors of Streptococcus,exist in several kinds of human and animal pathogenic bacterial,including Streptococcus pyogenes,Strepstococcus iniae and Streptococcus anginosus.SLS is a peptide toxin encoded by nine consecutive genes (sagA-sagⅠ).The functions of SLS include contributing pathogenic bacterium to pass through epithelial barrier,causing tissue damage,resisting to phagocytic clearance of host immune cells and interacting with other virulence factors.In addition,SLS as a signaling molecule of cell quorum sensing is involved in regulating the expression with other virulence factors.This paper summarized the structures and the biological functions of SLS in Streptococcus infection.

Objective To study the role of gasless laparoscopic techniques in the treatment of abdominal trauma. Methods A retrospective analysis was made on clinical data of 52 cases of abdominal trauma considered unfit for pneumoperitoneum treated by gasless laparoscopic surgery. Results Prompt diagnosis and treatment were achieved in 43 cases. A conversion to laparoscopic exploration under pneumoperitoneum was required in 5 cases. The remaining 4 cases of severe injuries of the spleen and the bowel were cured by a conversion to open surgery after the determination of the incision site under gasless laparoscope. There were no fatal cases in the study. Conclusions Use of gasless laparoscopic techniques for the diagnosis, treatment and determination of incision site in patients with abdominal trauma considered unfit for pneumoperitoneum is feasible. It is a necessarily additional alternative to traditional laparoscopic surgery.

83 patients with severe pancreatitis, cancer of esophagus, gastrointestipal surgery and intestinal perforation were treated with TPN, clinical level of total protein, albumin, blood sugar and fat, body weight and nitrogen were measured. The results showed patients with TPN acquired active effects, such as fully enhancement of the utilization and adaptability of body, maintenance of positive nitrogen balance effectively, complement of the lost of albumin and Hb, improvement of metabolic condition, inhibition of glyconegenesis, reduction of the lost of fat and nitrogen and the decomposition of muscle protein. These improve the nitrogen condition, maitain the body in the positive. nitrogen balance, reduce thecllurence of complication and pro ide the better condition for the health.