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排序方式: 共有1427条查询结果,搜索用时 15 毫秒
41.
《The Journal of Applied Poultry Research》2015,24(2):246-256
This review presents a framework for assessing the efficacy of antimicrobials used to control necrotic enteritis (NE) caused byClostridium perfringens (CP) in the context of susceptibility testing and clinical efficacy, and their potential interactions with the intestinal microbiota of poultry. Practitioners have traditionally based their choice of antimicrobial agent on antimicrobial susceptibility testing, but there appears to be a lack of correlation with clinical efficacy for in-feed antimicrobials (particularly bacitracin and virginiamycin). Resistance patterns of CP and antimicrobials have been monitored using epidemiological cutoffs for minimal inhibitory concentration (MIC), which are not intended to guide therapy. Also, most data have been determined using CP isolates from healthy birds (i.e., potentially from commensal strains not known to be clinically relevant). It is believed that NE is caused by specific virulent CP strains (and potentially other bacteria) that proliferate and displace these commensals. The presence of resistant commensals is not necessarily detrimental (and may even be beneficial) if they inhibit the single CP strain dominance effect observed in acute NE. The choice of antimicrobial therapy in a clinical setting should thus be based on a variety of factors, including an accurate diagnosis, results of efficacy studies, prior experience at the premises in question, and interpretation of MIC data, recognizing that it is not necessarily well correlated with clinical efficacy. 相似文献
42.
M. Velhner G. Kozoderović E. Grego N. Galić I. Stojanov Z. Jelesić C. Kehrenberg 《Zoonoses and public health》2014,61(5):364-370
Quinolone‐resistant Salmonella Infantis (n = 64) isolated from human stool samples, food and poultry during the years 2006–2011 were analysed for their resistance phenotypes, macrorestriction patterns and molecular mechanisms of decreased susceptibility to fluoroquinolones. Minimum inhibitory concentrations (MICs) of nalidixic acid (NAL) and ciprofloxacin (CIP) were determined by the agar dilution procedure, and the susceptibility to additional antimicrobial agents was determined by the disc diffusion method. To assess the influence of enhanced efflux activity, MICs were determined in the presence and absence of the inhibitor PAβN. The results of pulsed‐field gel electrophoresis (PFGE) typing revealed that quinolone‐resistant S. Infantis in Serbia had similar or indistinguishable PFGE profiles, suggesting a clonal spread. All S. Infantis showed combined resistance to NAL and tetracycline, whereas multiple drug resistance to three or more antibiotic classes was rare (2 isolates of human origin). The MICs ranged between 512 and 1024 μg/mL for NAL and 0.125–2 μg/mL for CIP. A single‐point mutation in the gene gyrA leading to a Ser83→Tyr exchange was detected in all isolates, and a second exchange (Ser80→Arg) in the gene parC was only present in eight S. Infantis isolates exhibiting slightly higher MICs of CIP (2 μg/mL). The inhibitor PAβN decreased the MIC values of CIP by two dilution steps and of NAL by at minimum 3–6 dilution steps, indicating that enhanced efflux plays an important role in quinolone resistance in these isolates. The plasmid‐mediated genes qnr, aac(6′)‐lb‐cr and qepA were not detected by PCR assays. 相似文献
43.
W. R. B. Sylvester V. Amadi R. Pinckney C. N. L. Macpherson J. S. McKibben R. Bruhl‐Day R. Johnson H. Hariharan 《Zoonoses and public health》2014,61(6):436-441
Cloacal swabs from 62 green iguanas (Iguana iguana), including 47 wild and 15 domestic ones from five parishes of Grenada, were sampled during a 4‐month period of January to April 2013 and examined by enrichment and selective culture for the presence of Salmonella spp. Fifty‐five per cent of the animals were positive, and eight serovars of Salmonella were isolated. The most common serovar was Rubislaw (58.8%), a serovar found recently in many cane toads in Grenada, followed by Oranienburg (14.7%), a serovar that has been causing serious human disease outbreaks in Japan. Serovar IV:48:g,z51:‐ (formerly, S. Marina) highly invasive and known for serious infections in children in the United States, constituted 11.8% of the isolates, all of them being from domestic green iguanas. Salmonella Newport, a serovar recently found in a blue land crab in Grenada, comprised 11.8% of the isolates from the green iguanas. The remaining four less frequent serovars included S. Javiana and S. Glostrup. Antimicrobial susceptibility tests conducted by a disc diffusion method against amoxicillin–clavulanic acid, ampicillin, cefotaxime, ceftazidime, ciprofloxacin, enrofloxacin, gentamicin, nalidixic acid, streptomycin, tetracycline and trimethoprim–sulfamethoxazole showed that drug resistance is minimal, with intermediate susceptibility, mainly to streptomycin, tetracycline and cefotaxime. This is the first report of isolation and antimicrobial susceptibilities of various Salmonella serovars from wild and domestic green iguanas in Grenada, West Indies. 相似文献
44.
J. F. Prescott 《Equine Veterinary Education》2021,33(10):539-545
Antimicrobial stewardship (AMS) is the term increasingly used to describe the multiple approaches needed to sustain the efficacy of antimicrobial drugs in the face of the increasing development and spread of antimicrobial resistance in bacterial pathogens, and the global crisis in medicine that it is engendering. The concept and the practices associated with AMS continue to evolve but the general approach is a dynamic and multifaceted one of continuous improvement based on reducing, improving, monitoring and evaluating the use of antimicrobials so as to preserve their future efficacy and to protect human and animal health. Using many equine examples, this basic overview discusses the multiple and interacting elements of AMS: Practice guidelines, infection control and prevention, clinical microbiology, resistance and use surveillance, dosage, pharmacokinetics and pharmacodynamics, regulation, education and owner compliance, leadership, coordination and measurement. There have been impressive advances in recent years in reporting and analysis of AMR in horses, in the scrutiny and assessment of how antimicrobial drugs are used in horses and in identification of areas for improvement including dosing, surgical prophylaxis, infection control, development of practice standards and the use of clinical microbiology. Antimicrobial stewardship is taking shape as we start to see the emergence of evidence-based recommendations but far more is required. Containing and even rolling back AMR will need the continued engagement of practitioners, equine national and international practitioner organisations, researchers and educators in the academic community, horse owners, regulators and others. 相似文献
45.
46.
通过阐述动物源细菌耐药性的产生及演变趋势,分析抗生素在兽医领域中的应用情况,探讨动物细菌传染性疾病的防治策略,旨在了解细菌耐药性对动物细菌传染性疾病治疗的影响,为兽用药品特别是兽用细菌疫苗的发展提供参考,促进动物卫生安全和公共卫生安全。 相似文献
47.
香根鸢尾挥发油的化学成分分析及抗菌活性研究 总被引:2,自引:0,他引:2
采用GC-MS技术分析了新鲜的和自然陈化的鸢尾挥发油的化学组成,确定了各种成分的化学结构与GC含量,并采用滤纸片琼脂平板扩散法与微量肉汤稀释法针对3种真菌和12种细菌(包括7种临床致病菌)进行了挥发油的药敏实验。结果表明:新鲜鸢尾挥发油共鉴定出26种成分,占总峰面积的92.09%,由醛类、酮类、酸类、酯类等化合物组成,其中十四酸(31.77%)、己酸(15.33%)、3-甲基丁酸(12.20%)、戊酸(9.29%)、庚酸(7.91%)、3-甲基戊酸(7.25%)、辛酸(2.44%)、2,4′-二羟基-3′-甲基苯乙酮(1.04%)是主要成分;自然陈化3年鸢尾挥发油共鉴定出45种成分,占总峰面积的85.63%,主要由醛类、酮类、酸类、酯类、醇类、酚类等化合物组成,其中十四酸(28.02%)、十四酸乙酯(10.42%)、(Z,Z)-9,12-十八碳二烯酸(7.67%)、十二酸(6.41%)、己酸(5.14%)、十六酸(4.44%)、十二酸乙酯(4.09%)、亚油酸乙酯(3.87%)、十六酸乙酯(3.13%)、油酸乙酯(2.85%)、6-甲基-α-紫罗兰酮(1.39%)、n-癸酸(1.31%)是主要成分;新鲜鸢尾挥发油对大部分微生物均具有很好的抗菌作用,其最低抑菌浓度(MIC)为0.25g/L,最低杀菌浓度(MBC)为0.35g/L;自然陈化3年鸢尾挥发油对大部分微生物均具有很好的抗菌作用,其MIC为0.05g/L,MBC为0.08g/L。 相似文献
48.
为改善空气质量,降解大气中的NOX,采用纳米TiO2光催化材料对涂料进行改性,然后喷洒在沥青道路表面。制备分散性及稳定性良好的纳米TiO2浆料,采用高速剪切与超声波震荡相接合的方法,通过正交试验得到最佳配比。考虑到涂料喷涂在沥青表面上的特殊环境,改性涂料应具备抗滑、耐水、冻融循环及良好的附着力等性能。经过一系列测试,结果表明:3%含量的纳米TiO2具有良好的分散性,用其制备的改性涂料能和沥青很好的结合,结合后其抗滑性、耐水性、冻融循环和附着力等均优于其他含量的涂料,适用于作为沥青路面表面喷涂的负载涂料。 相似文献
49.
50.
几种桉叶提取物的抗菌活性研究 总被引:2,自引:0,他引:2
研究了大叶桉、柠檬桉、尤曼桉(A、B)叶乙醇提取物和大叶桉、尤曼桉B叶提取物浓缩浸膏的石油醚、乙酸乙酯和正丁醇萃取组分对金黄葡萄球菌、大肠杆菌、枯草芽孢杆菌、黄瓜枯萎病菌的抗菌活性和以及这几种桉叶提取物的最低抑菌浓度。结果表明4种桉叶提取物对4种供试菌均有抑制作用,对金黄葡萄球菌、枯草芽孢杆菌抑制作用强,对黄瓜枯萎病菌作用弱。大叶桉、尤曼桉B提取物的抗菌活性强,这两种桉叶的乙酸乙酯和正丁醇萃取组分对4种供试菌抑菌作用最明显。 相似文献