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1A complete sequence and comparative analysis of a SARS-associated virus(Isolate BJ01)显示文摘The genome sequence of the Severe Acute Respiratory Syndrome (SARS)-associated virus provides essential information for the identification of pathogen(s), exploration of etiology and evolution, interpretation of transmission and pathogenesis, development of diagnostics, prevention by future vaccination, and treatment by developing new drugs. We report the complete genome sequence and comparative analysis of an isolate (BJ01) of the coronavirus that has been recognized as a pathogen for SARS. The genome is 29725 nt in size and has 11 ORFs (Open Reading Frames). It is composed of a stable region encoding an RNA-dependent RNA polymerase (composed of 2 ORFs) and a variable region representing 4 CDSs (coding sequences) for viral structural genes (the S, E, M, N proteins) and 5 PUPs (putative uncharacterized proteins). Its gene order is identical to that of other known coronaviruses. The sequence alignment with all known RNA viruses places this virus as a member in the family of Coronaviridae. Thirty putative substitutions have been identified by comparative analysis of the 5 SARS- associated virus genome sequences in GenBank. Fifteen of them lead to possible amino acid changes (non-synonymous mutations) in the proteins. Three amino acid changes, with predicted alteration of physical and chemical features, have been detected in the S protein that is postulated to beinvolved in the immunoreactions between the virus and its host. Two amino acid changes have been detected in the Mprotein, which could be related to viral envelope formation. Phylogenetic analysis suggests the possibility of non-human origin of the SARS-associated viruses but provides noevidence that they are man-made. Further efforts should focus on identifying the etiology of the SARS-associated virus and ruling out conclusively the existence of otherpossible SARS-related pathogen(s).QIN E'de ZHU Qingyu YU Man FAN Baochang CHANG Guohui SI Bingyin YANG Bao PENG Wenming JIANG Tao LIU Bohua DENG Yongqiang LIU Hong ZHANG Yu WANG Cui LI Yuquan GAN Yonghua LI Xiaoyu L Fushuang TAN Gang CAO Wuchun, YANG Ruifu Institute of Microbiology and Epidemiology, Chinese Academy of Military Medical Sciences, Beijing 100071, China WANG Jian, LI Wei, XU Zuyuan, LI Yan, WU Qingfa, LIN Wei, CHEN Weijun, TANG Lin, DENG Yajun, HAN Yujun, LI Changfeng, LEI Meng, LI Guoqing, LI Wenjie, L Hong, SHI Jianping, TONG Zongzhong, ZHANG Feng, LI Songgang, LIU Bin, LIU Siqi, DONG Wei, WANG Jun, Gane K-S Wong, YU Jun & YANG Huanming* Beijing Genomics Institute, Chinese Academy of Sciences, Beijing 101300 National Center for Genome Information, Beijing 101300, China 2003Chinese Science Bulletin2003,48,10:121
2Characteristics of Obesity and Its Related Disorders in China显示文摘Obesity is a medical condition with excess body fat accumulation to the extent which leads to serious health consequences.Abdominal obesity,also known as central obesity,refers to the presence of excess fat in the abdominal area.Obesity,especially abdominal obesity,contributes to many metabolic disorders including metabolic syndrome (MetS),type 2 diabetes (T2DM) and cardiovascular diseases (CVD).The incidence of obesity has increased dramatically in recent years worldwide.In China,more than one-third of adults are overweight or obese and 10%-20% of all adults are affected by MetS.The pathogenesis underlying the abdominal obesity remains unclear.The ultimate health outcome of obesity and its related metabolic disorders have prompted physicians to take aggressive treatments (lifestyle changes,pharmacological interventions and surgical therapies) before a serious consequence becomes clinically apparent.In this review,we discuss the prevalence,pathogenesis and clinic features of obesity in China.WEI-PING JIA ,CHEN WANG,SHAN JIANG,AND JIE-MIN PAN Department of Endocrinology and Metabolism,Shanghai Jiao Tong University Affiliated Sixth People’s Hospital,Shanghai Diabetes Institute,Shanghai Clinical Center of Diabetes,Shanghai 200233,China 2010Biomedical and Environmental Sciences2010,23,1:46
3The immunotherapeutic effect of dendritic cells vaccine modified with interleukin-18 gene and tumor cell lysate on mice with pancreatic carcinoma显示文摘AIM:To estimate the effect of a therapeutic vaccine against pancreatic carcinoma based on dendritic cell(DC)vaccine modified with tumor lysate and Interleukin-18 gene.METHODS:The BALB/C mice model of pancreatic arcinoma was induced with DMBA,DCvaccine was construted through pulsed with tumor lysate and transfected by the recombinant adenoviral vector encoding IL-18gene.The immnotherapeutic effects of DC vaccine on mice with pancreatic carcinoma were assessed (divided intoD-IL18-Lysate group,DC-Lysate group,DC-IL18 group,DC group,PBSgroup).RESULTS:After vaccination of the DC vaccine,the concentration of IL-18and IFN-γwere 2161±439ng·L^-1and435±72ng·L^-1inDC-IL18-Lysate group and there was significant difference compared with other groups(P<0.01)After vaccination of the DCcvaccine,the transplanted tumors were observed on 30days inDC-Lysate groups.on 16daysinDC-IL18groups.on3days in control group,but mice remained tumor-free for at least50days in DC-IL18-Lysate group and there was significant difference between DC-IL18-Lysate group and other groups(P<0.01).The median survival exceeds62days in DC-IL18-Lysate group.But the medsian surival was 48.6days in DC-Lysate group,33days in DC-IL-18group,17days in PBSgroup.The survival period was obviously prolonged in DC-IL18-Lysate group than in other groups(P<0.05,P<0.01).The weight of pancreatic tumor was0.22±0.083ginDC-IL18-Lysate group,1.45±0.74ginDC-Lysate group,1.89±1.34gin DC-IL18group,3.0±1.6ginDCgroup,2.9±2.0ginPBSgroup and the weight of tumor obviously reduced in DC-IL-18-Lysate group than in other groups(P<0.05,P<0.01).CONCLUSION:DC vaccine modified with tumo lysate and Interleukin-18gene can induce a specific and effective immune response against pancreatic cancinoma,cell.Zhao-Hui Tang Gao-Song Wu Sheng-Quan Zou Fa-Zhu Qiu Department of Surgery of Tong Ji Hospital Wen-Hong Qiu Department of immunology,Tongji Medical College,Huazhong University of Science and Technology,Wuhan 430030,Hubei Province,China Xiang-Ping Yang Department of Biochemistry,Rheinisch-Westfalische Technische Hochschule(RWTH),D-52074 Aachen,Germany 2002World Journal of Gastroenterology2002,8,5:37
4Carbon isotope composition of the Lower Triassic marine carbonates, Lower Yangtze Region, South China显示文摘Studies on three Lower Triassic sections located on the shallow water platform, the deep water slope and in the deep water basin in the Lower Yangtze Region, South China, show the similar trend of carbon isotope evolution. Biostratigraphic correlations among the Lower Triassic sections on the basis of standard conodont zones indicate that three negative shifts occurred in the Griesbachian, the Smithian and the late Spathian stages respectively, and one distinctly positive shift occurred in the early Spathian stage. Trend of carbon isotope evolution of the Lower Triassic reflects some significant changes in the global carbon cycle. Moreover, δ 13C background values are intensively controlled by palaeogeographic environment. In general, δ 13C values from deep-water slope carbonates are lighter than those from carbonate platform and heavier than those from deep-water basin carbonates. The positive carbon isotope excursion may be induced by a significant amount of organic carbon burial in marine sediments and increase in primary productivity. The large negative carbon isotope excursions during the Early Triassic in Lower Yangtze Region are interpreted to relate to volcano eruptions based on tuffaceous claystone interlayers observed near the Permian-Triassic boundary, the Induan- Olenekian boundary and the Lower Triassic-Middle Triassic boundary.ZUO Jingxun1,2, TONG Jinnan3, QIU Haiou4 & ZHAO Laishi3 1. Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences, Nanjing 210008, China 2. Henan Institute of Geological Survey, Zhengzhou 450007, China 3. State Key Laboratory of Geological Processes and Mineral Resources at China University of Geosciences, Wuhan 430074, China 4. Faculty of Material Sciences and Chemical Engineering, China University of Geosciences, Wuhan 430074, China 2006Science China Earth Sciences2006,49,3:32
5A meta-analysis of oxidative stress markers in schizophrenia显示文摘Oxidative stress has been identified as a possible element in the neuropathological processes of schizophrenia(SCZ).Alteration of oxidative stress markers has been reported in SCZ studies,but with inconsistent results.To evaluate the risk of oxidative stress to schizophrenia,a meta-analysis was conducted,including five markers of oxidative stress [thiobarbituric reactive substances(TBARS),nitric oxide(NO),catalase(CAT),glutathione peroxidase(GP) and superoxide dismutase(SOD)] in SCZ patients versus healthy controls.This study showed that TBARS and NO significantly increased in SCZ,while SOD activity significantly decreased in the disorganized type of SCZ patients.No significant effect size was found for the activities of GP and CAT in SCZ patients(P>0.05).Egger’s regression test observed no significant publication bias across the oxidative stress markers,but found high heterogeneities in all the 5 markers.The subgroup analysis suggested that the ethnicity,sample size of patients and sample sources may contribute to the heterogeneity of the results for TBARS,NO and SOD.The result further demonstrated the involvement of oxidative stress in the pathophysiology of schizophrenia.ZHANG Ming1,2,ZHAO ZhongMing3,HE Lin1,2,4 & WAN ChunLing1,2 1 Bio-X Center,Key Laboratory for the Genetics of Developmental and Neuropsychiatric Disorders(Ministry of Education),Shanghai Jiao Tong University,Shanghai 200030,China 2 Institutes for Nutritional Sciences,Shanghai Institute of Biological Sciences,Chinese Academy of Sciences,Shanghai 200031,China 3 Departments of Biomedical Informatics,Psychiatry,and Cancer Biology,Vanderbilt University Medical Center,Nashville,TN 37232,USA 4 Institutes of Biomedical Sciences,Fudan University,Shanghai 200032,China 2010Science China(Life Sciences)2010,53,1:32
6Corrigendum to “Properties improvement of SPEEK based proton exchange membranes by doping of ionic liquids and Y_2O_3”[Prog. Nat. Sci.: Mater. Int. 22 (1) (2012) 26-30]Jianbin Chen a, Qiang Guo a, Dan Li a, Juying Tong a,b, Xia Li a a School of Materials Science and Engineering, Shanghai University, Shanghai 201800, China b School of Wenling, Zhejiang TV University, Wenling 317500, China 2012Progress in Natural Science:Materials International2012,22,3:33
7The Chromosome-Level Reference Genome of Tea Tree Unveils Recent Bursts of Nonautonomous LTR Retrotransposons in Driving Genome Size Evolution显示文摘Dear Editor,The tea tree Camellia sinensis,a member of the genus Camellia in the Theaceae family,includes two major cultivated varieties,C.sinensis var.assamica(CSA\Assam type)and C.sinensis var.sinensis(CSS;Chinese type)(Ming and Bartholomew,2007).Due to the high economic importance of the tea tree,considerable efforts have been made to explore genetic basis of the biosynthesis of natural metabolites that determine health benefits and diverse tea flavors(Shi et al.,2011;Li et al.,2011;Li et al.,2015;Xia et aL,2017;Liu et al.,2019).Qun-Jie Zhang Wei L i Kui Li Hong Nan Cong Shi Yun Zhang Zhang-Yan Dai Yang-Lei Lin Xiao-Lan Yang Yan Tong Dan Zhang Cui Lu Li-Ying Feng Chen-Feng Wang Xiao-Xin Liu Jian-An Huang Wen-Kai Jiang Xing-Hua Wang Xing-Cai Zhang Evan E.Eichler Zhong-Hua Liu and Li-Zhi Gao 2020Molecular Plant2020,13,7:27
8Third-order point contact approach for five-axis sculptured surface machining using non-ball-end tools (Ⅰ): Third-order approximation of tool envelope surface显示文摘In this paper, the geometric properties of a pair of line contact surfaces are investigated. Then, based on the observation that the cutter envelope surface contacts with the cutter surface and design surface along the characteristic curve and cutter contact (CC) path, respectively, a mathematical model describing the third-order approximation of the cutter envelope surface according to just one given cutter location (CL) is developed. It is shown that at the CC point both the normal curvature of the normal section of the cutter envelope surface and its derivative with respect to the arc length of the normal section can be determined by those of the cutter surface and design surface. This model characterizes the intrinsic relationship among the cutter surface, cutter envelope surface and design surface in the neighborhood of the CC point, and yields the mathematical foundation for optimally approximating the cutter envelope surface to the design surface by adjusting the cutter location.ZHU LiMin1, DING Han2 & XIONG YouLun2 1 State Key Laboratory of Mechanical System and Vibration, Shanghai Jiao Tong University, Shanghai 200240, China 2 State Key Laboratory of Digital Manufacturing Equipment and Technology, Huazhong University of Science and Technology, Wuhan 430074, China 2010Science China(Technological Sciences)2010,53,7:25
9Microbial flocculant and its application in environmental protection显示文摘1IntroductionAlotofvariedflocculantshavebeenusedinwastewatertreatment,dredgingdownstreamprocessingandsomeindustrialfieldincl...Zhang Tong, Lin Zhe Department of Environmental Engineering, East China University of Science and Technology, Shanghai 200237, China Zhu Huai lan Department of Environmental Science, East China Normal University, Shanghai 200062, China 1999Journal of Environmental Sciences1999,11,1:25
10Diagnosis and treatment of polypoid lesions of the gallbladder:report of 194 cases显示文摘BACKGROUND: With the wide use of B-ultrasonography in recent years, the polypoid lesion of the gallbladde ( PLG) has been one of the most common diseases detected in biliary surgery. This study was to investigate the diag nostic method and operative indications of PLG. METHODS: The clinical and pathological data of 194 pa tients with PLG who had received operation at our hospita from January 1994 to September 2002 were analyzed retro spectively. Categorized data were analyzed by the chi square test. RESULTS: All the patients received preoperative B-ultra- sonography. 185 of the 194 PLG patients were diagnosed as having cholecystic polyp, and 9 adenomas. Among the 42 patients who received CT, 6 showed early gallbladder can cer. Pathologically, cholesterol polyps were mostly multi ple lesions (64.7%) with a mean diameter of3.86±2.2 mm in 136 patients. Of 16 patients with adenomas, 10 had a tumor diameter of more than 10 mm (62.5%). In 11 pa tients with gallbladder carcinoma, 7 were accompanied with gallbladder stone (63.6%). In addition, inflammatory polyps and adenomyomas were found in 25 and 6 patients respectively. CONCLUSIONS: B-ultrasonography is the most effective diagnostic method for detecting PLG. When large or irreg- ular lesions are found, CT should be performed in order to avoid missing of gallbladder carcinoma. Operative indica- tions for PLG include; a maximal tumor diameter of more than 10 mm; an over 50-year-old patient with a wide-base and a single polyp lesion; a wide-base lesion or a lesion showing a tendency to enlargement; co-existing gallbladder stone or cholecystitis; a patient without other diseases but obvious clinical features and failure of general ma- nagement ; big or long pedicels or polyps at the neck of the gallbladder for preventing the empty of the gallbladder and a history of biliary colic; and PLG with irregularly thick- ened local gallbladder wall.Xue-Jun Sun, Jing-Sen Shi, Yue Han, Jian-Sheng Wang and Hong Ren Xi’ an, China Department of Surgery, First Hospital of Xi’ an Jiao- tong University, Xi’ an 710061 , China 2004Hepatobiliary & Pancreatic Diseases International2004,3,4:24
11Phosphate removal and recovery through crystallization of hydroxyapatite using xonotlite as seed crystal显示文摘Xonotlite was synthesized and tested for phosphate removal and recovery from synthetic solution in a batch mode. The effects of pH, initial calcium concentration, bicarbonate concentration on phosphate removal through crystallization were examined. The morphology and X-ray diffraction (XRD) pattern of xonotlite before and after crystallization confirmed the formation of crystalline hydroxyapatite. The results indicated that the crystallization product had a very high P content (> 10%), which is comparable to phosphate rock at the dosage of 50-200 mg xonotlite per liter, with a maximum P content of 16.7%. The kinetics of phosphate removal followed the second-order reaction equation. The phosphate removal ability increased with increasing pH. The precipitation of calcium phosphate took place when pH was higher than 7.2, whereas the crystallization occurred at pH 6.0. A high calcium concentration could promote the removal of phosphate via crystallization, while a high bicarbonate concentration also enhanced phosphate removal, through that the pH was increased and thus induced the precipitation process. When xonotlite was used to remove phosphate from wastewater, the removal effciency could reach 91.3% after 24 h reaction, with removal capacity 137 mg/g. The results indicated that xonotlite might be used as an effective crystal seed for the removal and recovery of phosphate from aqueous solution.CHEN Xuechu, KONG Hainan, WU Deyi, WANG Xinze, LIN Yongyong School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China 2009Journal of Environmental Sciences2009,21,5:24
12The roles of heterogeneous chemical processes in the formation of an air pollution complex and gray haze显示文摘Urban and regional air pollutions are characterized by high concentrations of secondary pollutants such as photo-oxidants (mainly ozone) and fine particulate matter,which are formed through chemical reactions of the primary pollutants emitted from various sources.The accumulation of these pollutants under stagnant meteorological conditions results in the formation of gray haze,reducing visibility and causing major impacts on human health and climate.In an air pollution complex,the coexistence of high concentrations of primary and secondary gaseous and particulate pollutants provides a large amount of reactants for heterogeneous reactions on the surface of fine particles;these reactions change the oxidizing capacity of the atmosphere,as well as chemical compositions along with the physicochemical and optical properties of particulate matter,thereby accelerating formation of the air pollution complex and gray haze.Using in situ technologies,such as diffuse reflectance infrared Fourier-transform spectroscopy and single-particle Raman spectroscopy,we systematically investigated the reaction kinetics and mechanisms of gaseous pollutants (i.e.,NO2,SO2,O3,and formaldehyde) on the surfaces of the major components of atmospheric particles such as CaCO3,kaolinite,montmorillonite,NaCl,sea salt,Al2O3,and TiO2.We found that the main reaction products were sulfate,nitrate,or formate,which can change the hygroscopicity and light extinction parameters of those particles significantly.By analyzing the reaction kinetics of these heterogeneous reactions,we identified synergetic mechanisms of the three ternary reaction systems,i.e.,NO2-particlesH2O,SO2-particles-O3,and organics/SO2-particles–UV illumination.These synergetic mechanisms can provide experimental and theoretical bases for understanding the feedback mechanisms and nonlinear processes in the formation of an air pollution complex and gray haze.ZHU Tong,SHANG Jing & ZHAO DeFeng State Key Joint Laboratory of Environmental Simulation and Pollution Control College of Environmental Sciences and Engineering,Peking University,Beijing 100871,China 2011Science China Chemistry2011,54,1:24
13Heterogeneous reactions on the surface of fine particles in the atmosphere显示文摘Fine particles play an important role in the atmosphere. Research on heterogeneous reactions on the surface of fine particles is one of the frontier areas of atmospheric science. In this paper, physical and chemical characteristics of fine particles in the atmosphere and the interactions between trace gases and fine particles are described, methods used in heterogeneous reactions research are discussed in detail, progress in the study of heterogeneous reactions on the surface of fine particles in the atmosphere is summarized, existing important questions are pointed out and future research directions are suggested.DING Jie & ZHU Tong State Key Joint Laboratory of Environmental Simulation and Pollution Control, College of Environmental Sciences, Peking University, Beijing 100871, China Correspondence should be addressed to Zhu Tong (e-mail:tzhu@ pku.edu.cn) 2003Chinese Science Bulletin2003,48,21:24
14Global optimization of tool path for five-axis flank milling with a cylindrical cutter显示文摘In this paper, optimum positioning of cylindrical cutter for five-axis flank milling of non-developable ruled surface is addressed from the perspective of surface approximation. Based on the developed interchangeability principle, global optimization of the five-axis tool path is modeled as approximation of the tool envelope surface to the data points on the design surface following the minimum zone criterion recommended by ANSI and ISO standards for tolerance evaluation. By using the signed point-to-surface distance function, tool path plannings for semi-finish and finish millings are formulated as two constrained optimization problems in a unified framework. Based on the second order Taylor approximation of the distance function, a sequential approximation algorithm along with a hierarchical algorithmic structure is developed for the optimization. Numerical examples are presented to confirm the validity of the proposed approach.DING Han1 & ZHU LiMin2 1 State Key Laboratory of Digital Manufacturing Equipment and Technology, Huazhong University of Science and Technology, Wuhan 430074, China 2 School of Mechanical Engineering, Shanghai Jiao Tong University, Shanghai 200240, China 2009Science China(Technological Sciences)2009,52,8:23
15Third-order point contact approach for five-axis sculptured surface machining using non-ball-end tools(II): Tool positioning strategy显示文摘Based on the mathematical model describing the third-order approximation of the cutter envelope surface according to one given cutter location(CL),a tool positioning strategy is proposed for efficiently machining free-form surfaces with non-ball-end cutters.The optimal CL is obtained by adjusting the inclination and tilt angles of the cutter until its envelope surface and the design surface have the third-order contact at the cutter contact(CC)point,which results in a wide machining strip.The strategy can handle the constraints of machine joint angle limits,global collision avoidance and tool path smoothness in a nature way,and can be applied to general rotary cutters and complex surfaces.Numerical examples demonstrate that the third-order point contact approach can improve the machining strip width greatly as compared with the recently reported second-order one.ZHU LiMin 1 ,DING Han 2 &XIONG YouLun 2 1State Key Laboratory of Mechanical System and Vibration,Shanghai Jiao Tong University,Shanghai 200240,China 2State Key Laboratory of Digital Manufacturing Equipment and Technology,Huazhong University of Science and Technology,Wuhan 430074, China 2010Science China(Technological Sciences)2010,53,8:23
16Effect of N-desulfated heparin on hepatic/renal ischemia reperfusion injury in rats显示文摘AIM: To investigate the effect of N-desulfated heparin onhepatic/renal ischemia and reperfusion injury in rats.METHODS: Using rat models of 60 minutes hepatic or renalischemia followed by 1 h,3 h,6 h and 24 h reperfusion,animalswere randomly divided into following groups,the shamoperated controls,ischemic group receiving only normalsaline,and treated group receiving N-desulfated heparin ata dose of 12 mg/kg at 5 minutes before reperfusion. P-selectin expression was detected in bepatic/renal tissueswith immunohistochemistry methodRESULTS: P-selectin expression, serum ALT, AST, BUN andCr levels were significantly increased during 60 minuteischemia and 1 h, 3 h, 6 h and 24 h reperfusion,while theincrement was significantly inhibited,and hepatic/renalpathology observed by light microscopy was remarkablyimproved by treatment with the N-desulfated heparin.Furthermore,the heparin was found no effects on PT and KPTT.CONCLUSION: P-selectin might mediate neutrophilinfiltration and contribute to hepatic/renal ischemia andreperfusion. The N-desulfated heparin might preventhepatic/renal damage induced by ischemia and reperfusioninjury without significant anticoagulant activity.Tong Zhou Wei Song Feng Wang Department of Nephrology,Ruijin Hospital,Shanghai Second Medical University,Shanghai 200025,China Jin-Lian Chen Department of Gastroenterology,Shanghai Sixth People’s Hospital,Shanghai 200233,China Ming-Jun Zhang Animal Laboratory,Ruijin Hospital,Shanghai Second Medical University,Shanghai 200025,China Pei-Hua Ni,Department of Biochemistry,Shanghai Second Medical University,Shanghai 200025 Jian-Guo Geng Institute of Biochemistry and Cell Biology,Shanghai 200030,China 2002World Journal of Gastroenterology2002,8,5:20
17Deletion of Helicobacter pylori vacuolating cytotoxin gene by introduction of directed mutagenesis显示文摘AIM: To construct a vacA-knockout Helicobacter pylori mutant strain, whose only difference from the wild strain is its disrupted vacA gene.METHODS AND RESULTS: A clone containing kanamycin resistance gene used for homologous recombination was constructed in a directional cloning procedure into pBluescript ⅡSK, and then transformed into vacA+ H pylori by electroporation.Colonies growing on the selective media containing kanamycin were harvested for chromosomal DNA extraction,and the allelic exchange was determined by polymerase chain reactions and sequencing. Loss of vacuolating activity of the vaci-knockout strain was confirmed by examining the gastric cells co-cultured with cell-free supernatants from H pylori wild strain or the mutant.CONCLUSION: We constructed a vacA-knockout strain of H pylori through direct mutagenesis, which creates an important precondition for the future research on virulence comparison with gene expression analysis.Jian-Ping Yuan,Tao Li,Xiao-Dong Shi,Bao-Yu Hu,Gui-Zhen Yang,Shan-Qing Tong,Xiao-Kui Guo,Department of Microbiology and Parasitology,Shanghai Second Medical University,Shanghai 200025,China. 2003World Journal of Gastroenterology2003,9,10:20
18Antibiotic Resistance of Probiotic Strains of Lactic Acid Bacteria Isolated from Marketed Foods and Drugs显示文摘Objective To identify the antimicrobial resistance of commercial lactic acid bacteria present in microbial foods and drug additives by analyzing their isolated strains used for fermentation and probiotics. Methods Antimicrobial susceptibility of 41 screened isolates was tested with disc diffusion and E-test methods after species-level identification. Resistant strains were selected and examined for the presence of resistance genes by PCR. Results Distribution of resistance was found in different species. All isolates were susceptible to chloramphenicol, tetracycline, ampicillin, amoxicillin/clavulanic acid, cephalothin, and imipenem. In addition, isolates resistant to vancomycin, rifampicin, streptomycin, bacitracin, and erythromycin were detected, although the incidence of resistance to these antibiotics was relatively low. In contrast, most strains were resistant to ciprofloxacin, amikacin, trimethoprim/sulphamethoxazole, and gentamycin. The genes msrC, vanX, and dfrA were detected in strains of Enterococcus faecium, Lactobacillus plantarum, Streptococcus thermophilus, and Lactococcus lactis. Conclusion Antibiotic resistance is present in different species of probiotic strains, which poses a threat to food safety. Evaluation of the safety of lactic acid bacteria for human consumption should be guided by established criteria, guidelines and regulations.CHANG LIU, ZHUO-YANG ZHANG, KE DONG, JIAN-PING YUAN, AND XIAO-KUI GUO P1 P Department of Medical Microbiology and Parasitology, Institutes of Medical Sciences, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China 2009Biomedical and Environmental Sciences2009,22,5:19
19Metal chlorides loaded on activated carbon to capture elemental mercury显示文摘Activated carbon (AC) was considered to be an effective sorbent to control mercury in combustion systems. However, its capture capacity was low and it required a high carbon-to-mercury mass ratio. AC loaded with catalyst showed a high elemental mercury (Hg 0 ) capture capacity due to large surface area of AC and high oxidization ability of catalyst. In this study, several metal chlorides and metal oxides were used to promote the sorption capacity of AC. As a result, metal chlorides were better than metal oxides loaded on AC to remove gaseous mercury. X-ray diffractometer (XRD), thermogravimetric analyzer (TGA) and specific surface area by Brunauer- Emmett-Teller method (BET) analysis showed the main mechanisms: first, AC had an enormous surface area for loading enough MClx; second, Cl and MxOy were generated during pyrogenation of MClx; finally, there were lots of active elements such as Cl and MxOy which could react with elemental mercury and convert it to mercury oxide and mercury chloride. The HgO and HgCl 2 might be released from AC's porous structure by thermo regeneration. A catalytic chemisorption mechanism predominates the sorption process of elemental mercury. As Co and Mn were valence variable metal elements, their catalytic effect on Hg 0 oxidization may accelerate both oxidation and halogenation of Hg 0 . The sorbents loaded with metal chlorides possessed a synergistic function of catalytic effect of valence variable metal and chlorine oxidation.Zhemin Shen,Jing Ma,Zhijian Mei,Jianda Zhang School of Environmental Science and Engineering,Shanghai Jiao Tong University,Shanghai 200240,China 2010Journal of Environmental Sciences2010,22,11:18
20EXPERIMENTAL STUDY OF FLOWFIELD STRUCTURE AROUND AN OGIVE-CYLINDER显示文摘The flowfield structure and their aerodynamic characteristics over an ogive cylinder were studied by means of flow visualization and surface pressure measurement in a water tunnel and a wind tunnel. The existence of multi asymmetric vortices over long slender bodies was experimentally confirmed at large angles of attack and in the subcritical Reynolds number range. The spatial 3 D characteristics of the multi vortices system were analyzed and a physical model was developed. The topological structure of different patterns in cross flow plane was studied and the mechanism governing the formation of asymmetric vortices and multi vortices was discussed from the viewpoint of stability of the topological structure. It was concluded that the maximum in the sectional side force distribution curve are not caused by the shedding of higher position vortex, but by the cross over to the symmetric plane of the lower position vortex.Ph.D.Candidate:Wang Gang Fluid Mechanics Institute, Beijing University of Aeronautics and Astronautics, Beijing 100083, China,Supervisor: Deng Xue ying (Beijing University of Aeronautics and Astronautics) Members of Dissertation Defense Committee: Tong Bing gang (Graduate School of the Chinese Academy of Sciences),Chairman Gu Zhi fu (Peking University) Yang Qi de (China Aerodynamics Research and Development Center) Lv Zhi yong (Beijing University of Aeronautics and Astronautics) Liu Pei qing (Beijing University of Aeronautics and Astronautics) 2003Journal of Hydrodynamics2003,15,5:18
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