The aim of this study was to prepare chitosan film and to study its hemostatic properties. Chitosan film was prepared by casting the mixed solution of dialysed chitosan and gelatin after crosslinking with glutaraldehyde in a freeze dryer. Bleeding times were measured for bilateral back incisions (5 incisions on each side) in 4 New Zealand white rabbits. Using a randomized, blinded experimental design, one incision in each animal was treated with chitosan film, the other was treated with gauze. After bleeding stopped ,hemoglobin amount in films or gauzes was measured to determine the hemostatic effect. The results showed that the chitosan film adhered well to incisions. Bleeding times and hemoglobin amounts in chitosan film group were superior to those in gauze group( P

Standard electrical quantity (a), chronaxie (?), rheobase (Rh), "b" in Weiss' formula and intensity threshold of duration being 40 ?s and 300 ?s (T_(?) and T_(200)) were measured on peroneus nerves in rabbits. The results show that "a" is an actual index for measuring the excitability of various groups of fibers. The larger fibers, the higher excitability and the smaller "a" values. "b" does not indicate excitability. "?" , "Rh" , "T_(40)" and "T_(200)" are not actual indexes for measuring excitability because they are influenced by "b" in Weiss' formula.

Objective:To study the hemostatic and adhesion-prevention properties of gelatin-chitosan crosslinked film after craniotomy. Methods: Gelatin-chitosan crosslinked film was prepared by casting the mixed solution of dialyzed chitosan and gelatin after crosslinking with glutaraldehyde in freeze dryer. Bleeding time was recorded for bilateral back incisions (5 incisions on each side) in 4 New Zealand white rabbits. Incision on one side was treated with gelatin-chitosan crosslinked film, and on the other was treated with gauze. Hemoglobin amount in films or gauzes was measured to determine the hemostatic effect after bleeding. Bilateral craniotomies were performed at calvaria in 16 adult rabbits. A piece of gelatin-chitosan crosslinked film was put in one randomized side and the other side served as a control. The scar formation was evaluated grossly and histologically on week 2,4,8,12. Results:Bleeding time and hemoglobin amounts in gelatin-chitosan crosslinked film group were superior to those in gauze group(P

Objective:To study the psychosocial effect of fluorosis on students with dental fluorosis.Methods:115 students with different types of fluorosis were sampled randomly from fluorosis epidemic area of Xingtai city in Hebei province, including 60 of 12-year-old and 55 of 15-year-old students. Dental fluorosis was classified by Dean's Index (DI). Parents and teachers of the selected students were involved in a psychosocial questionnaire investigation which included five five-point questions, respectively.Results:Prevalence of fluorosis was 89.6% in the young students in the area. Evaluation scores by parents, which included “health of teeth”, “satisfaction of teeth” and “perceived well-being”, decreased with the decline of DI. Statistical difference was found in the answer to the five questions by parents when comparing the evaluation scores of control(without dental fluorosis) group,moderate dental fluorosis group and severe dental fluorosis group(P0.05). Difference of the evaluation scores of parents and teachers on boys and girls was not significant.Conclusion:Fluorosis has psychosocial impact on students, especially evaluated by parents.

We constructed prokaryotic recombinant expression vector of P61 gene from Nocardia brasiliensis,expressing P61 protein with biological activity in E.coli,and lay a foundation for further studies related to P61.P61 gene was synthesized and cloned into an expression vector pET-30a(+).The recombinant vector was transformed into Escherichia coli BL21 and induced with IPTG.The production was analyzed with Western blot and the catalase activity of P61 was tested with Catalase Assay Kit.The protein of P61was successfully expressed in E.coli with solubility and high catalase activity,and could be identified by anti-N.brasiliensis sera from mice.The prokaryotic expression plasmid of protein P61 was constructed successfully and can be expressed efficiently in E.coli BL21 cells with higher catalase.

Objective To study the effect of salidroside (Sal) on learning and memory abilities and expression of p75NTR signal transducers and Aβ in AD rat hippocampus.Methods Totally,ninety-six male SD rats were randomly divided into sham-operation group,model control group,Sal low,medium and high dose group,Hup-A group (16 rats in each group).Except for sham-operation group,AD model in the other group was established by slowly injecting 1μL(10 μg)Aβ1-40 in tobilateral hippocampal CA1 area.Sham-operation group was given the same volume of 0.9％ sodium chloride solution.Sal low,medium and high dose group took orally as early as 24 h postoperatively with salidroside 25,50,100 mg· kg-1 for 21days,while Hup-A group took 50 mg kg-1 of Hup-A orally.The same volume of 0.9％ sodium chloride solution was administrated in shanmoperation group and model control group.After administration,the learning and memory function of rats were tested by Morris water maze.The contents of Aβ in serum and hippacampus were determined by ELISA,and protein expression of p75NTR and p-JNK in the hippocampus of the rats were measured by ELISA.Results Compared with model control group,the latent time in water maze training of Sal low,medium and high dose groups were significantly shortened (P ＜ 0.05 or P ＜ 0.01),the number of times of crossing platform of Sal low,medium and high dose group was significantly increased.The contents of Aβ in the hippocampus and the protein expression levels of p75NTR and p-JNK in the hippocampus of Sal low,medium and high dose group were decreased significantly (P ＜ 0.05,P ＜ 0.01).Conclusion Salidroside has protective effects on learning and memory consolidation of dysmnesia rats caused by Aβ.Its mechanism might be related to inhibition of p75NTR regulation pathways for Aβ,reducing the neurotoxic effect of Aβ,so as to reduce cell apoptosis of hippocampus neuron.

AIM:To investigate the effects and mechanism of anti-vascular endothelial growth factor ( VEGF) assisted pars plana vitrectomy ( PPV) in the treatment of proliferative diabetic retinopathy ( PDR) . ·METHODS: A total of 92 patients ( 92 eyes ) with PDR treated by PPV were divided into the simple PPV group (41 patients with 41 affected eyes) and the combined treatment group ( 51 patients with 51 affected eyes ) according to whether the patient underwent intravitreal injection of Ranibizumab ( IVR) . The combined treatment group was treated with IVR at 5-7d before PPV. The surgical time, times of electrocoagulation, silicone oil filling rate, the incidence of postoperative complications, LogMAR BCVA of affected eyes, levels of VEGF and pigment epithelium derived factor ( PEDF ) in aqueous humor and vitreous body were compared between the two groups. ·RESULTS:The surgical time was shorter, the times of electrocoagulation was less, the silicone oil filling rate and the incidence rates of iatrogenic retinal hole and vitreous body hematocele were lower in the combined treatment group than in the simple PPV group (P<0. 05). Levels of VEGF and PEDF in aqueous humor and vitreous body of the combined treatment group during PPV were lower than those in the simple PPV group (P<0. 05). The LogMAR BCVA of the affected eyes of the combined treatment group in 3mo after surgery was better than that of the simple PPV group (P<0. 05). ·CONCLUSION:IVR combined with PPV can reduce the perioperative levels of VEGF and PEDF, reduce the times of electrocoagulation and the incidence of iatrogenic retinal hole and vitreous body hematocele, and improve the visual acuity of patients with PDR.

Objective:To evaluate the effects of Sander Ⅱ appliance in the orthodontic treatment of adolescent ClassⅡmalocclusion. Methods:15 cases (6 male and 9 female)of adolescent ClassⅡ malocclusion with mandibular retrution were treated with Sander Ⅱappliance.Pre-treatment and post-treatment Lateral cephalogram measurements were traced and analyzed in terms of 28 indicators. SPSS 19.0 software package was used for paired t test.Results:After treatment,15 patients achieved remarkable improvement in the maxillofacial profile and normal overjet of teeth.The cephalometric analysis showed that ANB,OJ,H°and U1-E decreased(P <0. 05),SNB,B-OLP,Pg-OLP(mm),Ii-OLP,Ms-OLP(mm),Mi-OLP(mm),N-Me,ANS-Me,S-Go,Go-Gn,N'-Pg'/FH,Cm-Sn-Ls and Pg-Pg'increased(P <0.05).There was no significant change in SN-MP,SN-OL and Y-axis before and after treatment. Conclusion:Sander Ⅱ appliance is effective in the treatment of adolescent early Class Ⅱmalocclusion.

The effect of phenol concentration on the structure and function of microbial communities,which were cultured in different conditions using coking wastewater biofilm as seeding,was investigated by Biolog and denaturing gradient gel electrophoresis(DGGE)methods.The less number of bands of cultivated sam-ples on the denaturing gradient gel electrophoresis fingerprint of 16S rRNA gene indicated reduction of di-versity after enrichment and cultivation.Some bands on the DGGE gel were significantly influenced by the phenol concentration in medium.The results of Biolog showed that the original biofilm sample had the highest substrate utility capacity as measured by average well color development(AWCD).But low concen-tration of phenol enriched sample S7 showed more diverse activity on the utility of Carboxylic acids.The principal component analysis(PCA)of Biolog data revealed that the metabolic patterns were similar when using the same phenol concentration,although the sample S7 much less similar to other cultivated samples.These results suggested that the enrichment and cultivation with phenol supplemented decreased the diver-sity and also changed the metabolic function of the microbial community.Lower phenol concentration in-creased the microbial community metabolic activity.The phenol degrading capacity of isolates from each samples indicated that the enrichment and cultivation condition had changed the type and property of cul-truable bacteria.Based on these results,we concluded that the different microorganisms will be isolated un-der different cultivation condition.

In China, traditional Chinese medicines （TCMs） have been used in clinical applications for thousands of years. The successful hyphenation of high-performance liquid chromatography （HPLC） and mass spectrometry （MS） has been applied widely in TCMs and biological samples analysis. Undoubtedly, HPLC/MS technique has facilitated the understanding of the treatment mechanism of TCMs. We reviewed more than 350 published papers within the last 5 years on HPLC/MS in the analysis of TCMs. The present review focused on the applications of HPLC/MS in the component analysis, metabolites analysis, and pharmacokinetics of TCMs etc. 50% of the literature is related to the component analysis of TCMs, which show that this field is the most popular type of research. In the metabolites analysis, HPLC coupled with electrospray ionization quadrupole time-of-flight tandem mass spectrometry has been demonstrated to be the powerful tool for the characterization of structural features and fragmentation behavior patterns. This paper presented a brief overview of the applications of HPLC/MS in the analysis of TCMs. HPLC/MS in the fingerprint analysis is reviewed elsewhere.