The formation of Staphylococcus epidermidis biofilm on the surface of medical biomaterials may resist the antibiotics treatment and cause chronic infection,which has become a research focus in recent years.Multiple genes constitute complex regulatory network which affect the biofilm formation,and play different roles in the different stages of biofilm formation.Accessory gene regulator (agr) is one of the most important genes in the process of biofilm formation.The process of bacterial biofilm formation,research status of regulation mechanism of agr system and its related genes in the formation of biofilm are reviewed,to provide reference of using agr as a target for the treatment of staphylococcus epidermidis biofilm related infections.

Lycopene—a kind of important active compound of caroteinoids, is greatly beneficial to human health with its diverse biological functions. With the elucidation of lycopene biosynthetic pathway and cloning genes of relative enzymes from microorganisms, it is possible to regulate lycopene biosynthesis via genetic engineering. The biosynthesis pathways of lycopene and gene cloning of lycopene biosynthetic enzymes in microorganisms were reviewed, and gene engineering strains documented in previous works including: E.coli and yeast constructed by genetic recombination, mold strains enhanced the ability of producing lycopene by gene manipulation were summarized. At last, compared with the present methods, the problems existed in the process of construction were pointed out.

Aim To study the effects of preconditioning with desflurane, sevoflurane and isoflurane on adenosine triphosphate (ATP) in anoxia-reoxygenation myocardial cells. Methods Rat ventricular myocytes, cultured for 4～5 days, were randomly allocated to five groups: Control group, anoxia-reoxygenation group and groups preconditioned with 1.5 MAC desflurane, sevoflurane or isoflurane following anoxia-reoxygenation. The content of intracellular ATP ,the activities of lactic dehydrogenase(LDH) and creatine kinase(CK), and the cell viability were measured at the end of experiment.Results Preconditioning with 1.5 MAC desfllurane, sevoflurane or isoflurane significantly attenuated the great reduction in ATP and cell viability and the increase of LDH and CK caused by anoxia-reoxygenation. There was a positive correlationship between ATP and cell viability,and a negatiue correlationship between LDH and CK (r was 0.83, -0.87 and -0.82 respectively, P

Objective To explore the impact of gratitude on interpersonal disturbance in college students and provide positive energy into the establishment of harmonious campus interpersonal relationship.Methods A total of 530 college students at 5 uni-versities in Guangdong province were surveyed by gratitude questionnaires and comprehensive diagnosis scale of interpersonal rela-tions.Results (1)The rate of interpersonal disturbance in college students was 46.4%.(2)Gratitude interacted with genders and grades(P <0.05 ).The levels of gratitude in male freshmen,sophomores,and seniors were remarkably higher than those in male juniors(P <0.01),and female juniors had a higher level of gratitude than their male counterparts remarkably(P <0.01).Scores of male students were significantly higher than those in female students in interpersonal communication,way of treating people,oppo-site-gender interaction and the total scores of interpersonal disturbance(P <0.01 ).Besides,juniors had a remarkably higher score than freshmen and seniors in the factor of social association and friend making (P <0.05 ).(3)There was a significantly negative correlation between the level of gratitude in college students and the total scores of interpersonal disturbance as well as the four fac-tors of interpersonal communication,social association and friend making,way of treating people,and opposite-gender interaction (P <0.01).Subjects with different levels of gratitude showed marked variation in the total scores of interpersonal disturbance and all its factors(P <0.01).Gratitude displayed a significantly negative predictive effect on the total scores of interpersonal disturbance and all its factors(P <0.01).Conclusion Close relation existed between gratitude of college students and their interpersonal dis-turbance,and gratitude could be used to effectively predict college students′interpersonal disturbance.

Objective To explore the angioarchitectrue characteristics and appropriate treatment strategies of dural arteriovenous fistula (DAVF) in foramen magnum region.Methods The clinical data of patients with DAVF diagnosed by digital subtraction angiography (DSA) were analyzed retrospectively.Results Thirteen patients intraoperative were found fistula and complete resection,patients discharged from hospital,DSA check showed that the DAVF fistula completely disappeared,all patients symptoms were improved to different extents.Conclusions The clinical features,prognosis and treatment methods of DAVF in forament magnum region depends on its angioarchitecture,especially the lesion site and venous drainage,surgical operation can usually find the fistula and can be completely removed.

Objective To investigate the pathological features of rabbit' retina at the early stage of sunlight-induced injury.Methods Twenty New Zealand rabbits without any eye diseases were randomly allocated to 4 groups(5 each): animals in group A were fed under normal illumination environment,the animals in group B were fed under normal illumination environment and exposed to constant simulated sunlight,the animals in group C were fed under low illumination environment,and the animals in group D were fed under low illumination environment and exposed to constant simulated sunlight.The pathological changes in rabbits' retina were observed with light and transmission electron microscope.Results The structure of retina in group A and group C were histologically well-defined,uniform in staining,and with regular cell shape.In the animals in group B,vesiculation occurred in the ganglion cell layer,inner nuclear layer and outer nuclear layer,and some of the mitochondria showed swelling.The intramembranous structure of external segments became disorganized.In the animals in group D,vesiculation and swelling occurred in the ganglion cell layer and inner nuclear layer,with disruption of the cell membrane.Vesiculation and swelling were also found in the outer nuclear layer,with reduction in cell quantity.The structure was disorganized,with disorganized cell membrane,obvious swelling of mitochondria,disorganized intramembranous structure of external segments,and loss and vesiculation of the laminal structure.Conclusion The rabbit' retina will be injured when it is exposed to 30 000 lux constant simulated sunlight for 30 minutes.Rabbits fed in a low illumination environment and exposed to constant simulated sunlight may suffer severer injury than those fed in a normal environment and exposed to constant simulated sunlight.

Objective:To observe the effect of combined Sanjin Tablets and antibiotic on women with urinary tract infection after sex life. Methods: 306 patients were randomly divided into two groups. The treatment group, taking oral SanJin Tablets and intravenous drip of ciprofloxacin, and the control group only ciprofloxacin given by intravenous drip, treatment course lasted for half a month. Results: In the treatment group, the total effective rate reached 96.77% and the rate of symptomatic improvement was 100.00%, and those indexes in the control group can only reached 80.00% and 82.35% respectively. There were obvious difference between the two groups in the rate of total effective rate and symptomatic improvement (P

Objective To study a new method for internal drainage and primary suture after laparoscopic choledocholithotomy (LCH). Methods Twenty-five patients with chronic cholecystitis combined with cholecystolithiasis and choledocholithiasis were performed laparoscopic cholecystectomy and choledocholithotomy and extraction of stones with choledoscopy. Results One case of Mirizzi' syndrome converted into laporotomy and 24 cases were successfully performed. Excluding neither internal nor external drainage was carried out with primary closure of common bile duct (CBD) in 1 case and T-tube were placed in 4 cases, the made-self 3mm～5mm diameter silica tubes with one-way hook were placed into the common bile duct for internally drainage in 19 cases. The time of operation was from 90 to 420 minutes with a mean of 145 minutes. 1～5 calculus were removed from CBD. A mean of hospitalized days stay was 7.5 day. Conclusions The operation of internal-tube drainage of LCH frees either the inevitably risk of hyper pressure of biliary duct because of the spasm of Oddi's sphincter or disadvantage of T-tube for drainage after LCH, which is new method both safety and practicality, both simpleness and easiness, and accords with the physiological needs of the human body.

Objective To study the possibility and safty of laparoscopic partial cholecystectomy in difficult cholecystectomy. Methods The operative procedures,efficaey and complications of 26 laparoscopic partial cholecystectomy between 1999 and 2001 were reviewed retrospectively.The operative indications were empyema cholecystitis, Mirris syndromeⅠtype,frozen Calot's triangle,shrunken gallbladder. Results operative time was (51?16 5) minutes;The time to recovey activity was (11?4 3) hours;food-intake began (22?8 5) hours after operation; The hospital stay was (4 5?1 5) days;bile leakage after operation was found in 2 cases and recovered after conservative management.Following-up period lasting 6 to 25 months showed no complecations occurred. Conclusions Laparoscopic subtotal cholecystectomy may simplify the operation and decrease the risk in difficult cholecystectomy,and can get the therapeutic result of cholecystomy combined with standard cholecystectomy.

Objective To investigate the feasibility and procedures of semi-open establishment of pneumoperitoneum(SOEPP) for laparoscopic surgery in patients with a history of abdominal surgery. Methods 117,patients,with a history of abdominal surgery received SOEPP and were retrospectively reviewed from October 1994 to January 2002. Results Out of 117 patients,pneumoperitoneum was established successfully in 115 cases by SOEPP.The successful rate of SOEPP was 98 3%(115/117). Conclusions SOEPP is a safe and feasible method in most patients with abdominal operative history.