检索结果-南通市图书馆

微纳电子技术 1984年第4期 76-81页

作者： E.t.Watkins 邓先灿

两端二极管器件可用于毫米波频率,而现在的FEt可达100GHz,甚至更高。

关键词：放大器波段器件电子设备 GaAsFEt 噪声系数 mic

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

60GHz GaAs FEt放大器

微纳电子技术 1983年第6期 60-63页

作者： E.t.Watkins 曹余录

用1/4μm栅结构研制出新的毫米波场效应晶体管(FEt)器件。这个器件在波导-微波集成电路(mic)放大器电路中从55～62GHz有5.0±0.5dB的增益,在60GHz下最小噪声系数为7.1dB。

关键词：放大器电路器件噪声系数 GaAs FEt FEt

Effects of Clarithromycin at Sub-Minimum Inhibitory Concentrations on Early ermB Gene Expression, Metabolic Activity and Growth of an erm(B)-Expressing Macrolide-Resistant Strain of Streptococcus pneumoniae

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Open Journal of Respiratory Diseases 2012年第1期2卷 1-8页

作者： Riana Cockeran H. C. Steel N. Wolter L. de Gouveia A. von Gottberg K. P. Klugman A. t. Leanord D. J. Inverarity t. J. Mitchell C. Feldman R. Anderson Division of Infection and Immunity Glasgow Biomedical Research Centre University of Glasgow Glasgow UK Division of Pulmonology Department of Internal Medicine Charlotte Maxeke Johannesburg Academic Hospital and University of the Witwatersrand Johannesburg South Africa Hubert Department of Global Health Rollins School of Public Health and Division of Infectious Diseases School of Medicine Emory University Atlanta USA Medical Research Council (MRC) Unit for Inflammation and Immunity Department of Immunology Faculty of Health Sciences University of Pretoria and Tshwane Academic Division of the National Health Laboratory Service Pretoria South Africa microbiology Department Southern General Hospital Glasgow UK Respiratory and Meningeal Pathogens Research Unit National Institute for Communicable Diseases of the National Health Laboratory Service and Faculty of Health Sciences University of the Witwatersrand Johannesburg South Africa

Aim: to investigate the effects of exposure of a macrolide-resistant [erm (B)-expressing] strain of Streptococcus pneumoniae (strain 2507) to clarithromycin (0.5 and 5 mg/L) added at the outset and 6 hours after initiation of culture on early gene expression, energy metabolism, and growth. Methods: Bacterial growth was determined by turbidometric and colony counting procedures, energy metabolism by measurement of AtP, while analysis of gene expression was performed using reverse transcription-PCR and sequencing. Results: Addition of clarithromycin, at either concentration, at the outset of culture, caused transient suppression of growth of 10 - 12 hours duration, while delayed addition of antibiotic (during the logarit.mic phase) resulted in an abrupt halt in growth followed by recovery. these inhibitory effects of clarithromycin on bacterial growth were associated with up-regulation of expression of erm(B), decreased AtP and protein synthesis, and were unaffected by inclusion of either catalase (500 and 1000 kunits/L), or competence-stimulating peptide (CSP-1, 0.5 mg/L). the inhibitory effects could, however, be overcome by pre-exposure of the bacteria to the antibiotic. Moreover, clarithromycin appeared to potentiate the ant.microbial actions of ceftriaxone, at sub-mic concentrations, for strain 2507. Conclusions: Unlike several other common bacterial pathogens, the full expression of erm(B)-mediated macrolide resistance by the pneumococcus has a slow onset, which is associated with transient susceptibility to macrolides and inhibition of growth.

关键词： Clarithromycin Macrolide-Resistance Pneumococcus

Associations between partial foot amputation level,gait parameters,and minimum impairment criteria in para-sport:A research study protocol

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Sports Medicine and Health Science 2022年第1期4卷 70-73页

作者： Fabio C.Lucas de Oliveira Samuel Williamson Clare L.Ardern Neil Heron Dina Christa Janse van Rensburg Marleen G.t.Jansen Sean O'Connor Linda Schoonmade Jane thornton Babette M.Pluim Center for Interdisciplinary Research in Rehabilitation and Social Integration CIUSSS-CNUniversite LavalQuebec CityQuebecCanada Research Unit in Sport and Physical Activity(CIDAF) Faculty of Sport Sciences and Physical EducationUniversity of CoimbraCoimbraPortugal English Institute of Sport LondonUK Division of Physiotherapy Karolinska InstituteStockholmSweden Center for Public Health Queen's University BelfastBelfastUK Department of General Practice Keele UniversityStaffordshireUK Section Sports Medicine Faculty of Health SciencesUniversity of PretoriaPretoriaSouth Africa Royal Dutch Lawn tennis Association(KNLtB) Amstelveenthe Netherlands Centre for Human Movement Sciences University Medical Centre GroningenUniversity of GroningenGroningenthe Netherlands School of Medicine Dentistry and Biomedical Sciences Centre for Public HealthQueen's University BelfastBelfastUK Medical Library Vrije Universiteit AmsterdamAmsterdamthe Netherlands Department of Family Medicine Schulich School of Medicine&DentistryUniversity of Western OntarioLondonOntarioCanada Department of Epidemiology&Biostatistics Schulich School of Medicine&DentistryUniversity of Western OntarioLondonOntarioCanada AMC/VUmc IOC Research Center of Excellence Amsterdam Collaboration on Health&Safety in Sports(ACHSS)AmsterdamNetherlands

Altered biomechanics due to amputation can contribute to substantial limitations,influencing sporting *** with lower extremity amputations or congenital lower limb deficiency are encouraged to participate in ***,to compete in Paralympic sports,the candidate must have an impairment that results in lower extremity loss of function and meets or exceeds the sport's minimum impairment criteria(mic).this review will focus on the mic for competitive wheelchair *** deficiency is known as one of the mic used to regulate participation in competitive para-sports since it impacts gait,kinematics,and biomechanics of both the upper and lower ***,it is questionable whether the mic concerning limb deficiency is set at the correct level for determining eligibility for participating in Paralympic *** study aims to provide an overview of the evidence examining the impact of different partial foot amputation(PFA)levels on gait as a proxy for sporting *** scoping review will be based on a 6-step methodological framework and Preferred Reporting Items for Systematic Reviews and Meta-Analysis,extension for scoping reviews(PRISMA-ScR).Studies will be selected from PubMed,Embase,CINAHL,and *** authors will screen the titles/abstracts *** studies will be scrutinised,and the same authors will extract *** will be relevant to informing the evidence-based development of mic for lower limb impairment after PFA and may be extrapolated to specific Paralympic sports,including wheelchair *** will be disseminated through scientific publications and conferences to audiences interested in Paralympic sports.

关键词： Amputees Congenital deficiency Gait analysis Paralympic sport Partial foot amputation Wheelchair tennis

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

BogorolA的固相全合成

中国医药工业杂志 2016年第1期47卷 73-73页

作者： Yamashita t 唐汉卿

Bogorol A[（E）-1]是一种抗耐甲氧西林金黄色葡萄球菌和抗万古霉素肠球菌的强效抗生素,在其线性12肽序列中有一个热力学不稳定的（E）-2-氨基-2-丁烯酰胺。本研究采用全固相合成策略高效合成（E）-1及其（Z）-型异构体[（Z）-1]。应用... 详细信息

Bogorol A[（E）-1]是一种抗耐甲氧西林金黄色葡萄球菌和抗万古霉素肠球菌的强效抗生素,在其线性12肽序列中有一个热力学不稳定的（E）-2-氨基-2-丁烯酰胺。本研究采用全固相合成策略高效合成（E）-1及其（Z）-型异构体[（Z）-1]。应用树脂上的无痕Staudinger连接立体构建得到（E）-和（Z）-2-氨基-2-丁烯酰胺部分。（E）-1和（Z）-1的抗菌活性相当（mic4mg/ml）。

关键词：全合成 BogorolA 固相合成高效合成热力学不稳定抗菌活性强效抗生素肽序列

维普期刊数据库

中链脂肪酸及其α-单脂肪酸甘油酯的抗菌研究——单一作用和协同作用

在线全文

学校读者我要写书评

暂无评论

福建畜牧兽医 2020年第1期42卷 56-59页

作者： Batovska D I todorova I t tsvetkova Ie 福州华康牧业有限公司技术部

对葡萄球菌属、棒状杆菌属、芽孢杆菌属、李斯特菌属和链球菌属的几种革兰氏阳性菌株进行中链脂肪酸及其α-单脂肪酸甘油酯的抗菌活性评价。α-单脂肪酸甘油酯比脂肪酸更具活性,其中α-单月桂酸甘油酯是最具活性的化合物。以化脓性链球... 详细信息

对葡萄球菌属、棒状杆菌属、芽孢杆菌属、李斯特菌属和链球菌属的几种革兰氏阳性菌株进行中链脂肪酸及其α-单脂肪酸甘油酯的抗菌活性评价。α-单脂肪酸甘油酯比脂肪酸更具活性,其中α-单月桂酸甘油酯是最具活性的化合物。以化脓性链球菌为试验菌,观察作用效果。首先,阻断α-单月桂酸甘油酯甘油部分的羟基,得到一种具有显著抗菌活性的化合物(mic,3.9μg/mL)。其次,考察α-单月桂酸甘油酯与α-单葵酸甘油酯两种成分混合物时,α-单月桂酸甘油酯与α-单葵酸甘油酯之间以及α-单月桂酸甘油酯与活性差的月桂酸之间的协同关系。其中一种成分优于另一种成分2倍的混合物比单独的某种成分更为活跃。此外,组成成分比例为1:1也是不利的。当α-单肉豆寇酸甘油酯的量等于或少于α-单月桂酸甘油酯时,α-单月桂酸甘油酯与单肉豆寇酸甘油酯对金黄色葡萄球菌209存在协同作用。

关键词：李斯特菌金黄色葡萄球菌化脓性链球菌中链脂肪酸 α-单脂肪酸甘油酯

维普期刊数据库

Design, Synthesis and Biological Evaluation of Novel Antitubercular Agents by Combining Pyrazoline and Benzoxazole Pharmacophores

在线全文

学校读者我要写书评

暂无评论

International Journal of Organic Chemistry 2016年第3期6卷 157-176页

作者： Hemal M. Soni Popatbhai K. Patel Mahesh t. Chhabria Ashish K. Patel Dharmraj N. Rana Pathik S. Brahmkshatriya M/S Piramal Enterprises Ltd. Piramal Discovery Solutions Plot No. 18 Pharmaceutical Special Economic Zone Village Matoda Ta. Sanand Ahmedabad India M.G. Science Institute Opp. Gujarat University Navrangpura Ahmedabad India Department of Pharmaceutical Chemistry L. M. College of Pharmacy Navrangpura Ahmedabad India Oxygen Healthcare Res. Pvt. Ltd. Plot No. 35 Panchratna Industrial Estate Near IBP Laxminarayan Petrol Pump Changodar Ahmedabad India

Various recent reports on tuberculosis have alarmed an increase in the patient class and subsequent death rates across the globe. Over and above the spread of more dangerous and fatal forms of tuberculosis like MDR-tB i.e. multiple-drug resistance tuberculosis, XDR-tB i.e. extensively-drug resistance tuberculosis & tDR-tB i.e. total-drug resistance tuberculosis has forwarded an urgent need to discover novel antitubercular agents. the current work is aimed at combining two previously well-known pharmacophores (pyrazoline and benzoxazole nucleus) in order to design and synthesize a series of novel benzoxazole-based pyrazoline derivatives. the synthesized target compounds were structurally confirmed by LCMS, 1H-NMR and 13C-NMR analysis. the target compounds were In vitro evaluated against M. tuberculosis H37Rv strain, multidrug-resistant tB (MDR-tB) and extensively drug-resistant tB (XDR-tB) strains. the In vitro screening results depicted that majority of the target compounds displayed potent activity with mic in a range of ~0.8 to 6.25 μg/mL. Many compounds were found to be more potent than isoniazid against MDR-tB with mic value 3.12 μg/mL and XDR-tB with mic value 12.5 μg/mL. Cytotoxicity assay of these active compounds on VERO cell lines also displayed good selectivity index.

关键词： Antitubercular Benzoxazole Pyrazoline Pharmacophore microplate Alamar Blue Assay

Resistance to Fluoroquinolones and Other Ant.microbials in Culture-Positive Salmonella typhiIsolates in Gulbarga, South India

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Advances in microbiology 2021年第1期11卷 16-26页

作者： Kavita Nagshetty N. G. Manjula Girish C. Math Arali Sagar Mohan C. t. Shivannavar S. M. Gaddad Department of P. G. Studies and Research in microbiology Gulbarga University Gulbarga Karnataka India Department of microbiology School of Basic and Applied Sciences Dayananda Sagar University Bengaluru Karnataka India

Background: typhoid fever is a major public health concern in developing countries. the upsurge in the occurrence of bacterial isolates that are resistant to nalidixic acid;with reduced susceptibility to ciprofloxacin in typhoidal Salmonellae constitutes a challenge to the clinician. Methods: In order to better understand the epidemiology of Salmonella infections in South India, Salmonella typhi isolates were screened from various healthcare centers. Salmonella isolates were identified by using standard phenotypic, serological, antibiotic susceptibility and molecular methods. Results: Among a total of 100 S. typhi isolates 9% were found to be multidrug resistant and 30% were nalidixic acid resistant. Isolates with reduced susceptibility to ciprofloxacin displays single base mutations in the gyrA gene. A very low rate of 1% resistance was found to ciprofloxacin. the only one isolate with ciprofloxacin mic ≥ 4 μg/ml also showed single mutation in the QRDR of the gyrA gene in S. typhi (GenBank accession no. HQ176349-HQ176368). Conclusions: A very low rate of nalidixic acid resistance with reduced susceptibility to ciprofloxacin was observed in comparison to other endemic areas in isolates of S. typhi from Gulbarga, South India, with steadily increasing NAR S. typhi but decreasing MDR isolations over the study period. this is most likely due to an increased use of ciprofloxacin as a first line drug of choice over more traditional ant.microbial agents for the treatment of typhoid fever.

关键词： Salmonella typhi Fluoroquinolones MDR NAR gyrA QRDR

Ant.microbial susceptibility testing in veterinary medicine:performance,interpretation of results,best practices and pitfalls

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

One Health Advances 2023年第1期1卷 62-77页

作者： Andrea t.Feßler Yang Wang Claire R.Burbick Dubraska Diaz-Campos Virginia RFajt Sara D.Lawhon Xian-Zhi Li Brian V.Lubbers Kelli Maddock Ron A.Miller Mark G.Papich Shabbir Simjee michael t.Sweeney Jeffrey L.Watts Congming Wu Jianzhong Shen Stefan Schwarz Institute of microbiology and Epizootics Centre for Infection MedicineSchool of Veterinary MedicineFreie Universität BerlinBerlinGermany Veterinary Centre for Resistance Research(tZR) Freie Universität BerlinBerlinGermany National Key Laboratory of Veterinary Public Health and Safety College of Veterinary MedicineChina Agricultural UniversityBeijingChina Key Laboratory of Animal Ant.microbial Resistance Surveillance Ministry of Agriculture and Rural AffairsCollege of Veterinary MedicineChina Agricultural UniversityBeijingChina Department of Veterinary microbiology and Pathology College of Veterinary MedicineWashington State UniversityPullmanWAUSA Department of Clinical Sciences College of Veterinary MedicineThe Ohio State UniversityColumbusOHUSA texas A&M University School of Veterinary Medicine College StationTXUSA Veterinary Drugs Directorate Health CanadaOttawaONCanada Department of Clinical Sciences College of Veterinary MedicineKansas State UniversityManhattanKSUSA North Dakota State University Veterinary Diagnostic Laboratory FargoNDUSA U.S.Food and Drug Administration Center for Veterinary MedicineRockvilleMDUSA College of Veterinary Medicine North Carolina State UniversityRaleighNCUSA Elanco Animal Health HookUK Zoetis Inc.KalamazooMIUSA.

the performance of ant.microbial susceptibility testing(ASt)of bacteria and the interpretation of ASt results for bacteria isolated from animals are complex tasks which must be performed using standard published methodology and overseen by experts in clinical microbiology and in consultation with clinical ***,ASt has significant potential for errors and *** this review,we provide guidance on how to correctly perform ASt of bacteria isolated from animals and interpret the ASt *** emphasis is placed on the various approved or published methodologies for the different bacteria as well as the application of interpretive criteria,including clinical breakpoints and epidemiological cut-off values(ECVs/ECOFFs).Application of approved interpretive criteria and definitions of susceptible,susceptible dose-dependent,nonsusceptible,intermediate,and resistant for clinical breakpoints as well as wild-type and non-wildtype for ECVs,are explained and the difficulties resulting from the lack of approved clinical breakpoints for other bacteria,indications,and animal species is *** requirement of quality controls in any ASt approach is also *** addition,important parameters,often used in monitoring and surveillance studies,such as mic50,mic90,and testing range,are explained and criteria for the classification of bacteria as multidrug-resistant,extensively drug-resistant or pandrug-resistant are *** mistakes are presented and the means to avoid them are *** provide the most accurate ASt,one must strictly adhere to approved standards or validated methodologies,like those of the Clinical and Laboratory Standards Institute or other internationally accepted ASt documents and the detailed information provided therein.

关键词： Ant.microbial susceptibility testing Quality controls Clinical breakpoints Epidemiological cut-off values Multidrug resistance

自发性病毒清除失败后,单用聚乙二醇干扰素α-2b治疗急性丙型肝炎患者24周的疗效

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

世界核心医学期刊文摘（胃肠病学分册） 2005年第7期1卷 51-52页

作者： Santantonio t. Fasano M. Sinisi E. 王铮 Clinic of Infectious Diseases University of Bari Policlinico Piazza Giulio Cesare 11 70124 Bari Italy

Background/Aims: Interferon (IFN) monotherapy significantly reduces the chron icity rate of acute hepatitis C (AHC) but optimal regimen and treatment timing r emain undefined. the aim of this study was to assess the efficacy of a 6- month course of pegylated IFN (PEG- IFN) α - 2b monotherapy in AHC patients and to investigate if IFN treatment initiated after 12 weeks from clinical presentatio n, still achieved a high response rate. Methods: Sixteen AHC patients still vire mic after 12 weeks from the onset were treated with PEG- IFN α - 2b (1.5 mcg/ kg once weekly) for 6 months and followed for at least 12 months. Response to th erapy was defined as normal ALt values and undetectable HCV RNA (t the end of therapy, after 6 (sustained r esponse) and 12 months follow- up (long- term response). Results: At the end o f treatment, HCV RNA was undetectable in 15/16 patients while ALt normalized in 14/16 patients. After 6 and 12 months follow- up, 15/16 patients (94% ) showed virological and biochemical response. Conclusions: A 6- month course of PEG- IFN α - 2b is effective in inducing resolution of AHC in 94% of patients. Ou r results provide a rationale for delaying treatment for 12 weeks, targeting onl y patients who fail to clear the virus spontaneously and truly requiring therapy without loss of efficacy.

关键词：丙型肝炎患者干扰素α 持续应答生化应答应答率诱导缓解 RNA

维普期刊数据库