Obstructive sleep apnea hypopnea syndrome(OSAHS) has been the main research area of the Dental Therapy Center for Sleep Apnea,Peking University School and Hospital of Stomatology.The basic research in the center includs: epidemic survey of OSAHS and snoring in a Beijing population,setting up the cephalometrc and MRI standard of airway and surrounding structures for non-snoring Chinese,aetology exploring OSAHS from views of airway size,craniofacial form,neck circumference and genioglossus muscle activity.Clinically,different dental appliances were developed.The treatment effects of the oral appliances for OSAHS patients were evaluated quantitatively.Two and three dimension changes of the airway and surrounding structures,genioglossus muscle activity,as well as snoring loudness following mandible advancing and opening were studied.Besides,research was expended to OSAHS in children recently.Under the support of National Nature Science Foundation 7 PhD and 3 MS students have graduated.More than 60 papers were published domestically and abroad and two awards were received from the National Ministry of Education and Chinese Medical Association in the past 10 years.This paper is a review of the past and current situation of dental research on OSAHS in China.

Objective To explore the role of new emergency mode "Green track" in treatment on traffic injuries. Methods The data of 2 947 patients with traffic injuries rescued by prehospital emergency "green track" and inhospital emergency treatment from March 1998 to January 2009 were retrospectively studied in aspects of prehospital and inhospital treatment methods and their results. Results Of all patients, 2 089 patients were treated surgically and 858 patients treated conservatively, in which 2 736 patients (92.8%) were cured but 211 (7.2%) died, with mortality rate of 7.2%. Head, face and limbs were the main injury parts. Of all, 1 874 patients (63.6% ) were admitted into the hospital within one hour after injury. Conclusions The new emergency mode "Green track" , either prehospital or inhospital, can markedly improve success rate of treatment for traffic injuries, increase survival rate and is of importance to be clinically applied.

Objective To investigate the effects of propofol administered before, with or after lipopolysaccharide (LPS) on the acute lung injury (ALI) induced by IPS in rats. Methods Seventy-six male Wistar rats weighing 250-290 g were randomly divided into 5 groups : (A) control group received only normal saline (n = 8); (B) LPS group received LPS 8 mg?kg-1 iv (n = 17); (C, D, E) propofol group-Ⅰ,Ⅱ, Ⅲreceived propofol (a bolus of 5 mg?kg-1 followed by infusion at 10 mg?kg-1?h-1) 1 h before (group C, propofol - Ⅰ , n = 17) , simultaneously with (group D, propofol-Ⅱ, n=17) or 1h after LPS administration (group E, propofol-Ⅲ , n = 17) . The animals were observed for 5h after LPS administration for MAP monitoring and mortality and then killed. The lungs were immediately removed for determination of expressions of nitrotyrosine protein and iNOS mRNA, wet / dry lung weight ratio and pulmonary permeability index (PPI). The lungs were also lavaged. The bronchoalveolar lavage fluid (BALE) was collected for measurement of TNF-?, NO and protein contents. Results In group C and D propofol given before and simultaneously with LPS significantly inhibited the increase in nitrotyrosine protein and iNOS expression induced by LPS, improved MAP, reduced 5h mortality rate, decreased PPI and protein, NO and TNF-?contents in BALF compared with group B (P

Objective To explore the differences between the conservative treatment and the operative treatment in the management of cervical spinal cord injury, and the timing of the operation. Methods The therapeutic effectiveness o f the 45 cases who were treated from October 1996 to January 2002 was analyzed. 21 of them underwent conservative treatment and 24 operative treatment. The corr elation between the therapeutic effects of the operation and its timing was expl ored. Results The myeloid functional recovery was poor in the patients who had b een treated with conservative means but good in those who had been given an oper ation. The earlier the operation, the more effective it could be, and the higher the probability of the myeloid functional recovery. Conclusions The operative treatment promises better outcome than the conservative treatment. To get the be st effects, the operation should be done within one month after the injury, for the longer the lapse between the injury and the operation, the worse the effect.

Cyclic voltammetry shows that, in a supporting ele ctrolyte of NaOH,riboflavine tetrabutyrate（RT）has a pair of cathodic and anodi c peaks at Hg electrode. The peak potentials Epc=Epa=-0.64　 V（vs.Ag/Agcl）.　The adsorptive characteristics of RT are explored in detai ls with various methods.　The adsorbed species is most probably neutral molecule of RT.The saturated adsorption amount of RT at Hg electrode is 5.42×10-11 　mol/cm2 and every RT molecule occupied 3.06　nm2. On the surface of HMDE ，the adsorption of RT obeys Frumkin dasorption isotherm. The adsorptive coeffic ient β，the attractive factor γ are 4.60×105，1.10 and the adsorption free energy ΔG, is　－32.30　kJ/mol, respectively. The electrode proc ess kinetic behavior has also been studied by using cyclic voltammetry. Under th e experimental conditions the rate constants for electron transfer are determine d. The values of ks are in good agreement with literature′s results.

To investigate peripheral blood mononuclear cells (PBMCs) infected by hepatitis C virus (HCV) and the influenceon T lymphocyte subset. Methods: Using non-isotopic in situ hybridization (NISH) and streptadivin-biotin-enzyme complex assay (SABC) todetect HCV-RNA, NS5 antigen and T lymphocyte subset. Results: 8(40.0% ) out of 20 patients with hepatitis C virus were HCV-RNA posi-tive in PBMCs, and among them 6(30.0％) were NS5 antigen positive simultaneously. NS5 antigen signals appeared diffusely within cyto-plasm, or in cell membrane, while HCV-RNA signals were mainly distributed in cytoplasm. Both the proportion of NS5 positive cell and HCV-RNA positive cells were very low (≤3％).The proportion of positive cellsane, while HCV-RNA signals are very low (≤3％). The proportionof CD4+ T cells was lower in the patients comparing with that in control group, the proportion of CD8+ T cells was higher, and the ratio ofCD4+/CD8+ were decreased remarkably (P＜0.01). Moreover the proportion of CD4+ T cells was lower in HCV-RNA-positive group com-paring with that in HCV-RNA-negative group, the proportion of CD8+ T cells was higher, and the ratio of CD4+/CD8+ was reversed (P＜0.01). Conclusion:HCV can infect PBMCs and replicate in patients with chronic hepatitis C;CD4+ T cells are readily damaged after PBMCsinfected by HCV, which causes the decrease or reversal of the ratio of CD4+/CD8+, undermines the ability of the body clearing virus and re-sults im chronicity of HCV infection.

Objective: To design and develop a preadjusted appliance based on Chinese normal occlusion, and to apply it in treatment of malocclusion cases.Methods: According to the results of the research performed in Department of Orthodontics, School of Stomatology of Peking University about teeth position and morphology of 67 Chinese with normal occlusion, the preadjusted appliance with the optimal prescription for Chinese has been designed and developed (Z1 appliance). Z1 appliance has been used in treatment of malocclusion cases. The efficiency of Z1 appliance was evaluated. Results:The treatment of 30 non-extraction cases and 16 extraction cases has been completed with Z1 appliance. A quite good result of clinical application of Z1 appliance was represented. Conclusion: Z1 appliance could be used in treatment of Chinese malocclution. The bracket base for anterior teeth was too thick and need more improvement.

Objective To study the polymorphisms of the large mutiplefunctional protease (LMP2) genes in women with severe pre-eclampsia (S-PE) and the sharing rate of LMP 2 in these women and their partners and couples. Methods Totally, 102 S-PE women and their husbands were enrolled in the study group, and 200 normal pregnant women and their husbands as control. The types of LMP2 alleles were assessed by polymerase chain reaction-restriction fragment lengthpolymorphism method (PCR-RFLP) after PCR. Results The frequency of LMP2R/H in S-PE group was significantly higher than that of the control (53.9% vs 35.%, P

Objective To study the cytochemical changes of hepatocytes in mice exposed to hypoxia. Methods The mice were divided into two groups(n=45, all males, hypoxia group=36, control group=9). The mice of the hypoxia group lived in hypoxia (O 2:10%). Using imaging analytical instrument LEICA-500IW, We observed cytochemical changes of the hepatocytes. The PAS, LDH, cytochrome oxidase, Mg 2+ dependent ATPase activity of hepatocytes was assayed. Results Compared with the controls, the LDH activity of hepatocytes increased dramatically, the longer the hypoxic time, the higher the LDH activity of the hepatocytes; the cytochrome oxidase activity of hepatocytes decreased sharply, the longer the hypoxic time, the lower the cytochrome oxidase activity of the hepotocytes.Conclusion Hypoxia can injury the hepatocytes of the mice and result in sharp changes of the hepatic cytochemistry.;

Objective To establish a new method for the determination of quercetin and kaempferol in wine by high performance liquid chromatography (HPLC) with chemiluminescence. Methods The procedure was based on the chemiluminescent enhancement by quercetin and kaempferol of the K3Fe(CN)6 system in an alkaline medium. The HPLC with post-column chemiluminescence was established for the determination of quercetin and kaempferol in wine. Results The standard curves were linear in the concentration ranges of 2.0?10-6-1.6?10-2 g/ml(r=0.999 0)for quercetin and 3.2?10-6-2.0?10-4 g/ml(r=0.999 8)for kaempfero respectively.The limits of detection were 1.4 ?10 -9 g/ml for quercetin and 3.4 ?10 -7 g/ml (S/N =3)for kaempfero respectively. The rates of recovery were 99.31% for quercetin and 99.06% for kaempferol. Conclusion The method is simple,rapid,accurate and applicable to the determination of quercetin and kaempferol in wine.