Chitin is one of the most important component in fungal cell wall.Biosynthesis of chitin is a complex processes and needs several chitin synthase isoenzymes.The knowledge of structure,function and regulation of chitin synthases is mainly derived from the study of Saccharomyces cerevisiae.In contrast with the 3 chitin synthases in S.cerevisiae,7 were found in most filamentous fungi.In this review the classification and function of chitin synthases are summerized,and progress in the studies on chitin synthases of filamentous fungi which are of theoretical or medical or agricultural importance,including Aspergillus nidulans,Aspergillus fumigatus and Ustilago maydis are emphasized.Recent ad-vance of research on chitin synthase as antifungal target is also discussed.

Sophoramine ( Sa ) is an alkaloid from sophora alopecuroides. Linn., in anesthetize animals ( cat, rat and rabbit), intravenous adminstra-tion of Sa reduced rapidly and markly the arterial blood pressure. The mechanism of hypotension effect of Sa is mainly attributable to its sympathetic ganglionic blocking and direct vasodilatation. Experiment on the isolated hearts of guinea pig revealed that Sa produced negative chronotropic and positive inotropic action, and increased coronary flow simultaneously.In a study of experimental arrhythmia in animals,we observed that Sa could reduce the arrhythmia induced by aconitine in rats and decreased the incidence of ventricular fibrillation induced by chloroform in mice.

ALS is a progressive neurodegenerative disease affecting both lower and upper motor neurons,including the pyramidal tract.There have been no objective and effective method to evaluate the lesions of upper motor neurons.With non-invasive,sensitive and macroscopic advantages,the application of Regular MR,MRS,DWI,function MR and VBM on ALS will undoubtedly have great potentials in the diagnosis,disease monitor and therapy of ALS.

Objective To evaluate the effect of endoscopic ultrasonography(EUS)in diagnosing e- sophageal and gastric varices in portal hypertension(PHT)patients.Methods Fifty-three patients with e- sophageal and gastric varices(EV、GV)of decompensation PHT and 20 patients without PHT as control were undergone EUS and esophagogastroduodenoscopy(EGD)simultaneously.EUS detected mainly the EGV,e- sophagus and stomach collateral veins.Results EUS identified EV endoscopically in 29(54.7%)patients. EUS detected GV in 24(45.3%)patients,compared with detection in 18(34.0%)patients by esopha- gogastroduodenoscopy(EGD)(P＜0.001).EUS detected PEV in 27(51%)patients.Distribution rates of PEV in F1,F2 and F3 are 0%,28.6% and 75% respectively.The comparison between groups shows sig- nificant difference(P＜0.001).Splenic vein can be seen in both control and experimental groups with di- ameter 7.5?1.35mm VS 11.5?3.5mm respectively,the difference between two groups is significant(P＜0.001).Proximal diameters of Azygos vein in two groups is 7.36?1.29mm VS 8.77?2.94mm respective- ly.Significant difference can be found(P＜0.05).Conclusion EUS had significant value in the diagnosis of PHT with EV and GV,and especially in detecting abnormalities of extra-luminal veins.

Induced pluripotent stem cell is a landmark in the stem cell study field, which has rapidly developed in the past 10 years.By obtaining induced pluripotent stem cells from somatic cell, and then differentiating into cardiomyocyte, various cardiomyocyte disease models could be established,which can be used for research of disease mechanisms, drug screening and gene therapy.This review introduces the successfully established cardiomyocyte disease models from human induced pluripotent stem cells, and points out the problems and prospects.

BACKGROUND: It is believed that repetitive transcranial magnetic stimulation (rTMS) may produce such neurophysiological effects as regulating regional cerebral blood flow, neurotransmitters, local metabolism, and neuronal remodeling after nerve tissue injuries. The prognosis ofischemic stroke is related with the cortical function reconstruction in the ipsilateral and contralateral hemisphere of the lesion. Currently studies have not defined whether rTMS can affect the cortical function, protect ischemic neurons and promote motor functional recovery after cerebral ischemia.OBJECTIVE: To investigate the effects of rTMS on rat motor cortical excitability and neural function in acute stage of cerebral ischemia-reperfusion injury.DESIGN: Completely randomized experiment.SETTING: Electroneurophysiological Laboratory of Peking Union Medical College Hospital.MATERIALS: The experiment was completed in the Zoological Research Center of Peking Union Hospital from January to June 2004. Totally 22adult male healthy Wistar rats were randomly divided into treatment group and the control group with 11 in each.METHODS: After determination of the average motor threshold of the right hind limbs, which was 22% of the maximum output, the rats were subjected to middle cerebral artery occlusion for 1 hour followed by reperfusion for 72 hours. At each time point of immediately and at 12, 36 and 60 hours after the initiation of reperfusion, the rats in the treatment group received rTMS treatment (20 Hz, 40% maximum output, 5 seconds for each session with an between-session interval of 2 minutes for a total of 10 sessions), and the site for motor threshold evaluation was used for rTMS stimulation; the rats in the control group recevied no treatment after model establishment. Motor threshold testing was performed in both groups 4 hours after the last session of treatment to avoid immediate-early effects of rTMS on the motor threshold. At 24 and 72 hours of reperfusion, the scores of neural function were recorded according to evaluation systems. All the rats with scores between 1 and 3 were enrolled in statistical analysis were evaluated between.MAIN OUTCOME MEASURES: ① Motor threshold of the rats in both groups before and after injury; ② Neural function scores at 24 and 72 hour reperfusion; ③ Infarct volume at 72 hour of reperfusion.RESULTS: Totally 13 rats entered the final result analysis. Before injury,motor threshold in the treatment and control group was similar (P=0.71),and after the injury, the motor threshold of the control group was 1.49times that of the treatment group but such difference was not statistically significant [(41.62±24.73)% vs (28.00±9.35)%, t=-1.17, P=0.27]. At 24hours of reperfusion, the functional scores of the treatment group and control group were not significantly different (P=0.46), but at 72 hours, the scores of the treatment group were significantly lower than that of the control group (1.60±1.52 vs 7.75±3.62, t=-3.57, P=0.004). The average infarct volume of two groups was (62.00±60.88) mm3 and (20.00±12.41) mm3 at 72 hours of reperfusion, respectively, which, after logarithm transformation,was not significantly different between the two group (t=-1.31, P=0.22),but when the infarct volume was transformed into Log10 values, a significant difference occurred between them (P=0.045).CONCLUSION: rTMS may stabilize and prevent the increment of the motor threshold, time-dependently relieve the neural function disability and reduce the infarct volume after cerebral ischemia-reperfusion injury.

Objective:To explore the influences of different sexes and ages on children static balance at the basis of quantitative comparison study of static postural balance of children aged 6-8(-year-odl).Method:A total of 499 children aged 6-8-year-old were recruited,which include 254 boys and 245 girls.Static postural balance test of these subjects was performed by using KY-1112 system for stabilometric analysis with subjects opening and closing eyes situations.Result:①There was a significant gender difference in static balance.At gender comparison,there was a significant difference on 3 indicators at the situations with eyes opening(P<0.05),and 3 indicators at the situations with eyes closing(P<0,01).②A significant difference Was shown in age comparison on 5 indicators(P<0.05).The mean of 5 indicators decreased with age growing.As compared with the value among Eve Area(with eyes opening and closing)and Track location Variance (with eyes opening).there Was a significant difference between children aged 8-year-old and 6-7-year-old(P<0.01),and no significant difference between 6-year-old and 7-year-old.There was a very significant difference on the LNG indicators at the situations with eyes opening and closing(P<0.01).③The value R indicator Was less than 1.Conclusion:To the children aged 6-8-year-old,there was significant gender difference in static balance,the balance function of girls was better than that of boys;there was significant age difference in static balance,with age growing the static balance rose also;relatively speaking,the gravity center shaking area was larger at forward and backward than that at leftward and rishtward.

Objective:To explore the perioperative dynamic changes of cellular immune function and its clinical significance in patients with chest surgery.Methods:The numbers of CD3、CD4、CD4/CD8、CD8 T lymphocyte and nature killer(NK) cells in peripheral blood were examined in 45 patients with chest surgery before operation and 1、3、5 and 7 days after operation by flow cytometry.45 patients were devided randomly into groups.The perioperative changes of T lymphocyte subsets and NK cells were compared among mediastinal disease,pulmonary operation,esophagus and gastric cardia surgery.Results:CD4/CD8 decreased 1 day after surgery and CD4 decreased at the 3rd postoperative day in patients with chest surgery.In patients with mediastinal disease,CD4/CD8 decreased 1 day after surgery and CD4 decreased at the 3rd postoperative day.In patients with pulmonary operation,CD8 decreased at the 1st day and 7th day after surgery.NK cells decreased at the 5th postoperative day CD3 increased at the 5th day after surgery.CD4/CD8 increased at the 7th day after operation.In patients with esophagus and gastric cardia surgery,CD4/CD8 decreased 1 day after operation,CD3 and CD4 increased at the 7th postoperative day.All differences are statistically significant( P

The Risk-sharing agreements have achieved remarkable success in improving patients'access to drugs, lowering the uncertainty of the drugs cost-effectiveness, financial risk control and other aspects of medical in-surance fund , so they have attracted widespread attention by the concerned governments and insurers .This paper sys-tematically reviewed the patient access schemes in UK from several aspects , including the origin of the program , clas-sification , application processes and the implementation effects as well .The results of the research indicated that Chi-na has basically met the conditions for implementation of the risk-sharing agreements .In order to gradually promote the risk-sharing agreements implementation , this paper suggests that China should clarify the main root of risk-sharing agreements implementation , establish risk-sharing agreements standardization process and strengthen the application of health technology assessment in health resources allocation to improve the Chinese medicines bargaining system more scientifically and efficiently .

0.05);between YMDD mutation and YMDD negative,there was statistical difference(P0.05),between YMDD mutation and YMDD negative, there was significant difference(t=12.76,P