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 clinical effect of renal artery embolization for renal graft dysfunction.Methods A total of 17 patients with renal graft dysfunction were treated by embolizing the renal graft artery.Coil embolization was performed on 7 of the cases,and gelfoam combined with coil was used in the other 10.Results Among the 17 patients,14 discontinued immunosuppressant in 3 weeks after the embolization,and 2 discontinued after receiving low-dose cortisones for about 6 months,and showed good recovery during follow-up.The other patient underwent resection of the renal graft because of continuous fever and graft pain.After the embolization,14 cases developed 'post-embolization syndrome'.Coil migration occurred in 1 case during the procedure.One patient experienced angina during the operation,and developed myocardial infraction the day after the embolization.Conclusions Renal artery embolization is safe and effective for patients with renal graft dysfunction.By using the method,open surgery can be avoided.Attention should be paid to potential complications.

Objective: To observe the relationship between homocysteine(Hcy)and spatial cognitive ability and to evaluate whether vitamin B12 supplementation could protect spatial cognitive ability in rats. Methods: The rats were randomized into three groups. The experimental group was given methionine subcutaneously. The intervention group was given methionine and vitamin B12 subcutaneously. The control group received isometric normal saline. After being raised for 8 weeks, all rats were examined for plasma Hcy and serum vitamin B12 and scores of Y-maze test. The brain tissues of hippocampus were checked immunohistochemically for acetylcholinesterase (AChE). Results: The experimental group developed hyperhomocysteinemia and descreased spatial cognitive ability significantly (P0.05). Conclusion: Homocysteine can impair the spatial cognitive ability in rats and vitamin B12 is effective in lowering Hcy level and protect the spatial cognitive ability of rats.

ObjectiveTo investigate the clinical features of acute myocardial infarction in CAPD patients.MethodsCompare the clinical and laboratory data of 39 patients with CAPD and AMI for the first time (PD group),including clinical symptoms,signs,electrocardiogram changes,myocardial enzyme changes and in hospital mortality,with those of 50 patients without renal insufficient but with AMI for the first time (C group).Diagnosis of AMI was made in hospital.ResultsCompared to C group, the symptoms presented at first in PD group were more atypical and the patients went to see doctor more lately after AMI.Atypical electrocardiogram changes were more in PD group than in C group (61.5% vs 26.0%,P

length of the spine.

With statistics and anatomic description, the extensor and flexor thigh muscles in francois leaf monkey were studied. Using stepwise regression, the origins and insertions' of the muscles, showing significant correlationship with the femur (E), are only the distance from the most anterior point of origin of the m. sartorius to the acetabular fossa (A) (r=0.68, t=3.33, P

Objective To improve the estimation and the percentage of electrogastrogram(EGG)slow wave rhythm with power spectrum estimation and calculation rule set.Methods Chirp Z-transformation was introduced for estimation power spectrum of EGG,which can obtain both high frequency resolution and accurate estimation of power;while the power proportion of main frequency components in each segment was used to substitute for conventional method in time domain.Results The variance of proposed method was about one-eighth of that of conventional method.Incorporating the power proportion of main frequency components,the proposed method gave better results especially for those EGG signals in which abnormal frequencies appeared frequently.Conclusion As compared with the conventional method,the proposed method is less affected by segmentation process in estimating the percentage of EGG slow wave rhythm,which may promote future clinical applications.

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.