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Effects of Chinese Fructus Mume Formula and Its Separated Prescription Extract on Insulin Resistance in Type 2 Diabetic Rats 被引量:2
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作者 李井彬 徐丽君 +4 位作者 董慧 黄诏宜 赵炎 陈广 陆付耳 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2013年第6期877-885,共9页
The effect of Fructus Mume formula and its separated prescription extract on insulin resis- tance in type 2 diabetic rats was investigated. The rat model of type 2 diabetes was established by feed- ing on a high-fat d... The effect of Fructus Mume formula and its separated prescription extract on insulin resis- tance in type 2 diabetic rats was investigated. The rat model of type 2 diabetes was established by feed- ing on a high-fat diet for 8 weeks and by subsequently intravenous injection of small doses of strepto- zotocin. Rats in treatment groups, including the Fructus Mume formula treatment group (FM), the cold property herbs of Fructus Mume formula treatment group (CFM), the warm property herbs of Fructus Mume formula treatment group (WFM), were administrated with Fructus Mume formula and its sepa- rated prescription extract by gavage, while the rats in diabetic model group (DM) and metformin group (MET) were given by gavage with normal saline and metformin correspondingly. The body weight be- fore and after treatment was measured, and the oral glucose tolerance test (OGTT) and the insulin re- lease test (IRT) were performed. The homeostasis model assessment-insulin resistance index (HOMA-IR) was calculated. The protein and mRNA expression levels of Insr, β-arrestin-2, Its-1 and Glut-4 in the liver, skeletal muscle and fat tissues were detected by using Western blotting and RT-PCR respectively. The results demonstrated that, as compared with DM group, OGTT, IRT (0 h, 1 h) levels and HOMR-IR in treatment groups were all reduced, meanwhile their protein and mRNA expression levels of Insr, Irs-1 and Glut-4 in the liver, skeletal muscle and fat tissues were obviously increased, and their protein and mRNA expression levels of β-arrestin-2 in the liver and skeletal muscle tissues were also markedly increased. It was suggested that the Fructus Mume formula and its separated prescription extracts could effectively improve insulin resistance in type 2 diabetic rats, which might be related to the up-regulated expression of Insr, Irs-1 and Glut-4 in the liver, skeletal muscle and fat tissues, and β-arrestin-2 in the liver and skeletal muscle tissues. 展开更多
关键词 Fructus Mume formula separated prescription type 2 diabetes insulin resistance β-arrestin-2
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Dynamic resistive switching in a three-terminal device based on phase separated manganites
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作者 王志强 颜志波 +2 位作者 秦明辉 高兴森 刘俊明 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第3期293-297,共5页
A three-terminal device based on electronic phase separated manganites is suggested to produce high performance resistive switching. Our Monte Carlo simulations reveal that the conductive filaments can be formed/annih... A three-terminal device based on electronic phase separated manganites is suggested to produce high performance resistive switching. Our Monte Carlo simulations reveal that the conductive filaments can be formed/annihilated by reshaping the ferromagnetic metal phase domains with two cross-oriented switching voltages. Besides, by controlling the high resistance state(HRS) to a stable state that just after the filament is ruptured, the resistive switching remains stable and reversible, while the switching voltage and the switching time can be greatly reduced. 展开更多
关键词 phase separation dielectrophoresis resistive switching memory device
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Study on Screening of Fungi with High-resistance against Chromium and on Related Characteristics 被引量:4
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作者 赖洁玲 唐晓燕 +3 位作者 钟礼松 林谦 吴弦华 韦明肯 《Agricultural Science & Technology》 CAS 2011年第12期1765-1768,共4页
[Objective] The aim was to separate chromium-resistant microorganism from soil contaminated by chromium.[Method] Separation and purification technique was used as follows:different concentrations of Cr^6+ were added... [Objective] The aim was to separate chromium-resistant microorganism from soil contaminated by chromium.[Method] Separation and purification technique was used as follows:different concentrations of Cr^6+ were added into medium,and chromium-resistant fungi were screened after separations and domestications.The selected fungi were under preliminary identification according to its morphological and colony characteristics.Then,related biological characteristics were studied,including measurement of growth curve,growing effects by temperature,pH value and osmotic pressure.[Result] The Cr(VI) with concentration of 1 000 mg/L was separated and selected from soils in ten different places contaminated seriously by heavy metal in adjacent region of Yulin City.Considering its morphological and colony characteristics,it was preliminarily identified as saccharomycetes,which can well grow within 15-37 ℃,and whose most suitable temperature was 28℃.Bacterial strain can grow well with pH of 4-10,and the optimum pH was 7.2;besides,it can grow well with NaCl concentration of 0.5%-5.0%.Through the experiment,the bacteria was found with resistance not only to chromium,but also to heavy metals such as Pb+Cu,Cu+Fe,Pb+Fe,and Pb+Cu+Fe.[Conclusion] The fungi selected from the experiment were of good adaptability to natural environment,and it also had resistance to other heavy metals. 展开更多
关键词 Bcteria with resistance to Cr(Ⅵ) separation and selection Biological characteristics
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Flow-resistance analysis of nano-confined fluids inspired from liquid nano-lubrication:A review 被引量:3
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作者 Xianzhu Huang Jian Wu +3 位作者 Yudan Zhu Yumeng Zhang Xin Feng Xiaohua Lu 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2017年第11期1552-1562,共11页
How to reduce flow resistance of nano-confined fluids to achieve a high flux is a new challenge for modern chemical engineering applications, such as membrane separation and nanofluidic devices. Traditional models are... How to reduce flow resistance of nano-confined fluids to achieve a high flux is a new challenge for modern chemical engineering applications, such as membrane separation and nanofluidic devices. Traditional models are inapplicable to explain the significant differences in the flow resistance of different liquid–solid systems.On the other hand, friction reduction in liquid nano-lubrication has received considerable attention during the past decades. Both fields are exposed to a common scientific issue regarding friction reduction during liquid–solid relative motion at nanoscale. A promising approach to control the flow resistance of nano-confined fluids is to reference the factors affecting liquid nano-lubrication. In this review, two concepts of the friction coefficient derived from fluid flow and tribology were discussed to reveal their intrinsic relations. Recent progress on low or ultra-low friction coefficients in liquid nano-lubrication was summarized based on two situations. Finally, a new strategy was introduced to study the friction coefficient based on analyzing the intermolecular interactions through an atomic force microscope(AFM), which is a cutting-point to build a new model to study flowresistance at nanoscale. 展开更多
关键词 Flow resistance Membrane separation Liquid nano-lubrication MODEL Intermolecular interactions AFM
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Isolation and Identification and Drug Resistance Analysis of Avian Escherichia coli and In Vitro Competition with Lactobacillus
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作者 Li Juan Liu Qiuchen +5 位作者 Zhai Hongxu Wang Yehua Jiang Guotuo Lin Yang Liu Yan Shan Chunqiao 《Animal Husbandry and Feed Science》 CAS 2020年第1期6-10,共5页
[Objective]The paper was to understand the resistance of commonly used clinical antibiotics to avian Escherichia coli and the inhibition of lactobacillus against pathogenic E.coli.[Method]The strain was isolated and i... [Objective]The paper was to understand the resistance of commonly used clinical antibiotics to avian Escherichia coli and the inhibition of lactobacillus against pathogenic E.coli.[Method]The strain was isolated and identified by SS medium culture,microscope examination,PCR amplification and biochemical test,and the sensitivity of avian E.coli to eight antibiotics was determined by disk diffusion method.Twelve strains of avian E.coli and one strain of lactobacillus were divided into five group using in vitro liquid culture method,namely simultaneous mixed culture group of lactobacillus and E.coli,first colonization group of E.coli,first colonization group of lactobacillus,E.coli control group and lactobacillus control group,for competitive inhibition test between E.coli and lactobacillus.[Result]Totally 34 strains with similar characteristics to E.coli strains were preliminarily screened;the target band amplified by PCR was 293 bp,which was consistent with the expected size.The isolated strain could decompose maltose,sucrose,lactose,glucose,arabinose,mannitol and sorbitol;the nitrate reduction test was positive,while citrate and V-P test was negative,consistent with the biochemical characteristics of E.coli.The resistance rate of the isolates to cefalexin and tylosin was over 65%,and that to enrofloxacin and doxycycline was up to 50%;the isolates were more sensitive to apramycin,tilmicosin,neomycin and colistin,and the total resistance rate was below 15%.The inhibitory effects of mixed culture of lactobacillus and E.coli against E.coli was better than first colonization of lactobacillus at 24 h;the inhibitory effects of first colonization of lactobacillus against E.coli was better than that of mixed culture of lactobacillus and E.coli at 36 h;the inhibitory effects of mixed culture of lactobacillus and E.coli against E.coli was the best at 48 h.[Conclusion]The isolated strains of E.coli were generally resistant to eight commonly used antibiotics.Lactobacillus could inhibit the growth of avian E.coli in vitro,and first colonization of lactobacillus received the best effort. 展开更多
关键词 AVIAN E.COLI separation and identification DRUG resistance LACTOBACILLUS In VITRO COMPETITION
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聚酰胺膜耐氯改性及氯化修复研究进展
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作者 朱勤燕 李新冬 +4 位作者 包罗 郏江辉 于思伟 钟招煌 蔡勐 《中国环境科学》 北大核心 2025年第1期113-123,共11页
介绍了间苯二胺-均苯三甲酰氯和哌嗪-均苯三甲酰氯两种典型的PA膜,深入剖析其最新的氯化破坏机理.在此基础上,进一步探讨了针对这两种膜的耐氯改性方法,包括改变单体结构、本体掺杂技术、物理涂覆方法以及化学接枝手段等.对PA膜氯化修... 介绍了间苯二胺-均苯三甲酰氯和哌嗪-均苯三甲酰氯两种典型的PA膜,深入剖析其最新的氯化破坏机理.在此基础上,进一步探讨了针对这两种膜的耐氯改性方法,包括改变单体结构、本体掺杂技术、物理涂覆方法以及化学接枝手段等.对PA膜氯化修复领域的最新研究进展进行了简要论述,包括初期氯化后的还原法修复和氯化降解后的修补剂修复.分析表明,耐氯PA膜的研制仍面临巨大挑战,PA膜的耐氯改性研究应在不牺牲其分离性能的前提下,综合考虑膜的其他各项性能,灵活运用各种改性方法. 展开更多
关键词 聚酰胺膜 反渗透 纳滤 氯化破坏机理 耐氯改性 氯化修复 分离
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Influence of Poly(methyl metacrylate) Addition on Resistive Switching Performance of P3HT/P(VDF-TrFE) Blend Films
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作者 翁军辉 胡静航 +2 位作者 张剑驰 蒋玉龙 朱国栋 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2017年第2期200-206,I0002,共8页
Organic semiconducting/ferroelectric blend films attracted much attention due to their electrical bistability and rectification properties and thereof the potential in resistive memory devices. Blend films were usuall... Organic semiconducting/ferroelectric blend films attracted much attention due to their electrical bistability and rectification properties and thereof the potential in resistive memory devices. Blend films were usually deposited from solution, during which phase separation oc- curred, resulting in discrete semiconducting phase whose electrical property was modulated by surrounding ferroelectric phase. However, phase separation resulted in rough surface and thus large leakage current. To further improve electrical properties of such blend films, poly(methyl metacrylate) (PMMA) was introduced as additive into P3HT/P(VDF-TrFE) semiconducting/ferroelectric blend films in this work. It indicated that small amount of PMMA addition could effectively enhance the electrical stability to both large electrical stress and electrical fatigue and further improve retention performance. Overmuch PMMA addition tended to result in the loss of resistive switching property. A model on the configuration of three components was also put forward to well understand our experimental observations. 展开更多
关键词 resistive switching Ferroelectric/semiconducting blend film Spin coating Phase separation
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Electrospinning organic solvent resistant preoxidized poly(acrylonitrile)nanofiber membrane and its properties 被引量:2
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作者 Zhiwei Du Jinxue Cheng +2 位作者 Qinglin Huang Mingxing Chen Changfa Xiao 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2023年第1期289-299,共11页
A high performance preoxidized poly(acrylonitrile)(O-PAN)nanofiber membrane with excellent solvent resistance,thermal stability and flexibility was fabricated by the preoxidation of electrospun PAN nanofiber membrane.... A high performance preoxidized poly(acrylonitrile)(O-PAN)nanofiber membrane with excellent solvent resistance,thermal stability and flexibility was fabricated by the preoxidation of electrospun PAN nanofiber membrane.The performance of resultant O-PAN nanofiber membrane was optimized by altering the PAN concentration and preoxidation temperature.The results showed that the O-PAN nanofiber membrane which made from PAN concentration of 14%(mass)and preoxidation temperature of 250.0℃ have a more optimal comprehensive performance.In the long-term separation test of SiO2 particle(1 μm)in DMAc suspension,the permeate flux of O-PAN nanofiber membrane stabilized at 227.91 L·m^(-2)·h^(-1)(25℃,0.05 MPa)while the SiO2 rejection above 99.6%,which showed excellent solvent resistance and separation performance.In order to further explore the application of the O-PAN nanofiber membrane,the OPAN nanofiber membrane was treated with fluoride and used in oil/water separation process.The O-PAN nanofiber membrane after hydrophobic treatment showed excellent hydrophobicity and good oil/water separation performance with the permeate flux about 969.59 L·m^(-2)·h^(-1)while the separation efficiency above 96.1%.The O-PAN nanofiber membrane exhibited a potential application prospect in harsh environment separation. 展开更多
关键词 Poly(acrylonitrile)(PAN) PREOXIDATION Nanofiber membrane Solvent resistance Oil/water separation
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锂离子电池耐热隔膜的研究进展
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作者 刘天伟 赵展鹏 +2 位作者 范浩波 陈美玉 王秋实 《印染》 CAS 北大核心 2024年第12期70-74,80,共6页
锂离子电池(LIB)因能量密度高、循环寿命长等优点,广泛应用于便携式电子产品和大型储能设备中。综述了传统聚烯烃隔膜改进和本征耐热隔膜研发的研究现状及相关机理。在传统聚烯烃隔膜方面,研究主要集中在高热阻系数的无机陶瓷颗粒涂覆... 锂离子电池(LIB)因能量密度高、循环寿命长等优点,广泛应用于便携式电子产品和大型储能设备中。综述了传统聚烯烃隔膜改进和本征耐热隔膜研发的研究现状及相关机理。在传统聚烯烃隔膜方面,研究主要集中在高热阻系数的无机陶瓷颗粒涂覆和化学接枝、共价交联等有机耐热改性两类方法;在本征耐热隔膜方面,无机陶瓷隔膜、耐热聚合物隔膜以及有机-无机复合隔膜被广泛研究,这些隔膜材料在高温环境中表现出优异的热稳定性、机械性能和电化学性能。通过分析上述方法发现,材料选择、材料改性和结构设计可以显著提升LIB隔膜的耐热性能,同时尽量减少对其力学性能和电化学性能的不利影响。未来研究应集中在利用有机-无机复合材料的性能特点来优化隔膜材料的综合性能,并开发成本低、性能优异的耐热隔膜,从而推动LIB的安全应用和市场推广。 展开更多
关键词 锂离子电池 耐热隔膜 安全性能 本征耐热材料
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聚乙烯醇/聚磷酸铵改性锂电隔膜的制备与性能
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作者 许德涟 乔庆东 +2 位作者 李琪 肖伟 李莹 《精细化工》 EI CAS CSCD 北大核心 2024年第1期159-165,232,共8页
以高聚合度的聚磷酸铵(APP)为阻燃剂,聚乙烯醇(PVA)为成膜骨架材料,通过相转化法制备了PVA/APP改性隔膜,并测定了改性隔膜的机械强度、湿润性、热稳定性、微观形貌以及电化学性能。探究APP添加量对改性隔膜性能的影响,将改性隔膜在充满... 以高聚合度的聚磷酸铵(APP)为阻燃剂,聚乙烯醇(PVA)为成膜骨架材料,通过相转化法制备了PVA/APP改性隔膜,并测定了改性隔膜的机械强度、湿润性、热稳定性、微观形貌以及电化学性能。探究APP添加量对改性隔膜性能的影响,将改性隔膜在充满氩气的手套箱中组装成锂电池,并评价其循环倍率性能。结果表明,当PVA水溶液质量分数为10%、APP添加量为8%(以PVA质量为基准)时,改性隔膜具有优异的电解液湿润性以及热稳定性,吸液率达到215.0%,在200℃下几乎不收缩;改性隔膜的拉伸强度达到47.4 MPa。在0.1 C倍率充放电条件下循环50次,放电比容量为143.2 mA·h/g,库仑效率均>97%,容量保持率达到95.1%,而商用锂电池隔膜所组装电池的容量保持率只有82.8%。 展开更多
关键词 锂电隔膜 聚乙烯醇 聚磷酸铵 耐热性 阻燃 有机电化学与工业
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耐有机溶剂型分离膜的制备及应用研究进展
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作者 王思思 赵洋 +3 位作者 程羽君 李成才 朱海霖 刘国金 《高分子材料科学与工程》 EI CAS CSCD 北大核心 2024年第1期159-167,共9页
有机溶剂的分离与纯化是近年来的研究热点,众多分离与纯化技术应运而生。耐有机溶剂膜分离技术具有高效节能、操作简便的优势,受到研究者们的普遍关注,在化工、环境、医药、纺织等领域具有广阔的应用前景。文中概括了耐有机溶剂型分离... 有机溶剂的分离与纯化是近年来的研究热点,众多分离与纯化技术应运而生。耐有机溶剂膜分离技术具有高效节能、操作简便的优势,受到研究者们的普遍关注,在化工、环境、医药、纺织等领域具有广阔的应用前景。文中概括了耐有机溶剂型分离膜的分离技术与分类,阐述了耐有机溶剂型分离膜的制备方法,介绍了耐有机溶剂型分离膜的应用进展,并对耐有机溶剂型分离膜的发展趋势进行了展望。综述内容可为耐有机溶剂型分离膜的推广和应用提供策略支撑。 展开更多
关键词 耐有机溶剂 膜分离技术 膜材料 制备方法 应用
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汉中地区某猪场仔猪腹泻性大肠埃希氏菌的分离鉴定及耐药性检测
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作者 王玉龙 蒋野 +6 位作者 李颖 王峰 蒋桂林 贾镛 李超 吕妮 马永华 《陕西农业科学》 2024年第8期95-99,共5页
为明确汉中某猪场仔猪腹泻的病原菌及其耐药情况,试验无菌采集腹泻仔猪病料,分离培养后经生化试验、16S rRNA PCR鉴定、药物敏感性试验以及小鼠致病性试验等研究进行探索。试验结果显示该分离株在各培养基上的菌落特征、革兰氏染色镜检... 为明确汉中某猪场仔猪腹泻的病原菌及其耐药情况,试验无菌采集腹泻仔猪病料,分离培养后经生化试验、16S rRNA PCR鉴定、药物敏感性试验以及小鼠致病性试验等研究进行探索。试验结果显示该分离株在各培养基上的菌落特征、革兰氏染色镜检结果及生化特性与大肠埃希氏菌相吻合;分离菌株16S rRNA序列与GenBank中登录的大肠埃希氏菌同源性达99%以上;分离菌株对氨苄西林、多黏菌素B、氯霉素、头孢曲松、头孢噻吩、头孢唑林等耐受,对头孢他啶、米诺环素、阿米卡星3种药物敏感,同时对多种抗生素产生耐药性;在小鼠致病性试验中发现48 h内试验组小鼠全部死亡且对照组无死亡,并从死亡小鼠组织中得到该菌株,说明分离菌有较强的致病力。结果表明,本试验所分离的病原菌为多重耐药致病性大肠埃希氏菌。本研究结果可为该猪场仔猪腹泻性大肠埃希氏菌病的临床防治提供科学依据。 展开更多
关键词 仔猪 大肠埃希氏菌 分离鉴定 耐药性
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尿液中药物与耐药污染及削减技术研究进展 被引量:1
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作者 徐国韬 周晓琴 +1 位作者 李子富 赵美娟 《中国环境科学》 EI CAS CSCD 北大核心 2024年第2期1122-1133,共12页
尿液回用有助于构建“人体-土壤-植物-人体”之间的可持续物质循环.然而尿液中残留的药物、耐药菌和耐药基因也会随着这一循环在环境中富集并最终回到人体,存在潜在健康风险.本文总结了源分离尿液中的药物及耐药污染特性,研究表明,尿液... 尿液回用有助于构建“人体-土壤-植物-人体”之间的可持续物质循环.然而尿液中残留的药物、耐药菌和耐药基因也会随着这一循环在环境中富集并最终回到人体,存在潜在健康风险.本文总结了源分离尿液中的药物及耐药污染特性,研究表明,尿液中已检测出34种药物,平均浓度在0.07~2.7×10^(3)μg/L之间,检出频率在0.7%~100%之间,尿液中已检出的耐药基因有12种.针对此类污染物去除,主要有自然储存法、吸附法、膜分离技术、电化学法、生物方法,其中电化学技术显示出对于尿液中抗生素抗性基因的良好去除效率,最多可去除尿液中4.18log的bla_(KPC),但是应用于实际现场处理时还需要通过设计更合理的电极材料来提高使用寿命、降低能耗.此外,大多削减技术仍处于实验室研究阶段,对已有技术进行优化或使用多种技术联合处理尿液以削减药物及相关耐药性污染是未来研究的重点. 展开更多
关键词 源分离尿液 耐药微生物 抗生素抗性基因 削减技术
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基于PMMS-Net和叶绿素荧光成像的绿豆叶斑病抗性鉴定方法
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作者 李洁 高尚兵 +3 位作者 余骥远 陈新 李士丛 袁星星 《中国农机化学报》 北大核心 2024年第8期210-216,共7页
考虑到相近发病指数的绿豆叶片病斑区域特征区分不明显,在检测类似大小的病斑时,使用固定尺度的卷积核检测效果不是很好,故设计一种并行多分支多尺度卷积神经网络(PMMS-Net)模型。该模型先使用并行多分支多尺度特征融合模块获取丰富的... 考虑到相近发病指数的绿豆叶片病斑区域特征区分不明显,在检测类似大小的病斑时,使用固定尺度的卷积核检测效果不是很好,故设计一种并行多分支多尺度卷积神经网络(PMMS-Net)模型。该模型先使用并行多分支多尺度特征融合模块获取丰富的病斑特征;然后采用坐标注意力机制,使模型能更好地定位到病变区域,实现对感兴趣区域的选择性强调;最后使用特征充分提取模块,将深度可分离卷积与普通卷积结合,实现对特征的充分提取,进一步优化特征提取效果。试验数据集由绿豆叶斑病的叶绿素荧光图像构成,其中包含五种抗性类型的绿豆叶斑病图像。结果表明,本文提出的方法在试验数据集上训练迭代1000次,所耗费时间仅比AlexNet多0.8倍,验证准确率却比AlexNet高出18.9%,本模型在该数据集上的验证准确率为87.8%,平均特异度为96.92%,参数内存仅为0.54 MB。本文提出的方法有利于将该模型部署在移动终端等资源受限的嵌入式设备上,为绿豆叶斑病的抗性鉴定提供一种新方法。 展开更多
关键词 绿豆叶斑病 抗性鉴定 叶绿素荧光图像 坐标注意力机制 深度可分离卷积
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加州鲈源型诺卡氏菌的分离鉴定及耐药性分析
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作者 尹生辉 赵桂新 +2 位作者 赵梅云 王春霞 史秋梅 《黑龙江畜牧兽医》 CAS 北大核心 2024年第18期124-129,137,共7页
为了确定引起河北省秦皇岛市3个养殖场加州鲈发病、大规模死亡的病原,试验共采集9尾加州鲈进行剖检,取结节内容物进行病原菌的分离、纯化及革兰氏染色、镜检,对分离菌进行生化鉴定、16S rDNA基因的序列分析、基因分型、毒力基因MCEIA检... 为了确定引起河北省秦皇岛市3个养殖场加州鲈发病、大规模死亡的病原,试验共采集9尾加州鲈进行剖检,取结节内容物进行病原菌的分离、纯化及革兰氏染色、镜检,对分离菌进行生化鉴定、16S rDNA基因的序列分析、基因分型、毒力基因MCEIA检测、致病性试验和耐药性分析,并选择合适的抗生素对养殖场病鱼进行治疗,观察效果。结果表明:病死加州鲈肝脏、心脏、脾脏、肾脏和腹膜均有针尖大小的白色结节。从昌黎县、卢龙县和海港区3个养殖场的病死加州鲈体内各分离到1株优势菌,分别命名为CLY-1、LL-2和HG-3。3株分离菌在血琼脂培养基培养72 h均形成沙粒状、粗糙、易碎、边缘不整齐、有褶皱的淡黄色菌落,革兰氏染色、镜检均为紫红色分枝状的革兰氏阳性菌。3株分离菌均为过氧化酶阳性、氧化酶阴性,均能够发酵硝酸盐、七叶灵、柠檬酸,但不能利用酪素、黄嘌呤、酪氨酸、淀粉、明胶、山梨醇和甘露醇,符合诺卡氏菌的基本生化特性。3株分离菌16S rDNA基因测序结果完全一致,均与GenBank中的诺卡氏菌参考株16S rDNA基因相似性在99.9%以上,与鰤型诺卡氏菌参考株(ATCC 43993、NS128、JCM 3360、HSY-NS02、NParks_Aq54-21)亲缘关系较近,与杀鲑诺卡氏菌参考株(DSM 4490、DSM 44488、R89、DSM 40472、W30)和星形诺卡氏菌(LMB-7)亲缘关系较远,基因分型结果与鰤型诺卡氏菌相符,且均携带毒力基因MCEIA。接种CLY-1株的加州鲈于攻毒后第5天开始死亡,第14天死亡率高达80%,病鱼临床表现和剖检结果与3个养殖场患病加州鲈一致。3株分离菌对各抗菌药物的耐药性一致,均对多西环素、卡那霉素、新霉素、替米考星、氟苯尼考、复方新诺明和磺胺间甲氧嘧啶敏感,对青霉素、氨苄西林、头孢拉定和磺胺二甲氧嘧啶耐药。选择多西环素和氟苯尼考两种抗生素以拌料形式给药,迅速控制了疫情。说明3个养殖场加州鲈大规模死亡的原因均为鰤型诺卡氏菌感染,用多西环素和氟苯尼考治疗取得了明显效果。 展开更多
关键词 加州鲈 诺卡氏菌 鰤型诺卡氏菌 分离 鉴定 耐药性分析
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猪源大肠埃希菌分离鉴定、耐药性、致病性研究及噬菌体分离 被引量:1
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作者 童谣 王文雪 +14 位作者 卢萌萌 张博扬 李皓斌 邢瑞洋 孙江涛 贾雨康 姚美慧 魏润钰 李栋梁 姜鹏 吕博 王梓旭 刘春雪 杜莉 任庆海 《养猪》 2024年第3期55-61,共7页
大肠埃希菌是引起仔猪腹泻常见的细菌病原体。本实验以山东省聊城市产房腹泻仔猪为研究对象,采集腹泻仔猪粪便,通过对细菌分离、纯化,经16s rDNA基因扩增及全基因组测序,最后确诊为大肠埃希菌,该菌株全基因组序列的全长为4584108 bp;并... 大肠埃希菌是引起仔猪腹泻常见的细菌病原体。本实验以山东省聊城市产房腹泻仔猪为研究对象,采集腹泻仔猪粪便,通过对细菌分离、纯化,经16s rDNA基因扩增及全基因组测序,最后确诊为大肠埃希菌,该菌株全基因组序列的全长为4584108 bp;并对分离到的大肠埃希菌进行药敏试验、耐药及毒力基因检测、小鼠致病力试验及对应的噬菌体分离纯化。结果表明,该大肠埃希菌为O11血清型,主要耐药基因为blaSHV、blaTEM、aadA1、sul1、tetA;主要毒力基因为fyuA、ler;对阿奇霉素、丁胺卡那、新霉素敏感,对头孢氨苄、阿莫西林、四环素类抗生素严重耐药;对小鼠致病力强(109 CFU/mL);同时,分离纯化了5株对应的大肠埃希菌噬菌体,为大肠埃希菌的多重防控提供理论依据。 展开更多
关键词 猪源大肠埃希菌 分离 耐药性 致病性 噬菌体
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带侧烷基聚酯型聚氨酯的微相分离与耐湿热性能
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作者 曾妍 易玉华 《高分子材料科学与工程》 CSCD 北大核心 2024年第11期11-18,共8页
为了分析侧烷基对聚酯型聚氨酯(PU)耐湿热性能的影响,分别采用聚己内酯二醇(PCL220N)、聚己二酸己二醇酯二醇(CMA2066)、聚己二酸-2-丁基-2-乙基-1,3丙二醇酯二醇(PBEPG)和聚己二酸-3-甲基-1,5戊二醇酯二醇(P2010)为软段制备了PU材料。... 为了分析侧烷基对聚酯型聚氨酯(PU)耐湿热性能的影响,分别采用聚己内酯二醇(PCL220N)、聚己二酸己二醇酯二醇(CMA2066)、聚己二酸-2-丁基-2-乙基-1,3丙二醇酯二醇(PBEPG)和聚己二酸-3-甲基-1,5戊二醇酯二醇(P2010)为软段制备了PU材料。红外光谱、动态力学热分析、热重分析和水接触角分析表明,侧烷基能提高PU软硬段间微相分离程度,软段的玻璃化转变温度降低,与水的接触角增大,耐湿热性能提高。带丁基、乙基双侧烷基的PBEPG-PU,其软段和硬段各自形成微区,观察到2个tanδ峰,微相分离程度高,拉伸强度为22.2 MPa,同时表面疏水性强,100℃,100%RH下老化36 h后拉伸强度保持率为71.2%,表现出较好的耐湿热性能和较高的力学强度。 展开更多
关键词 聚酯型聚氨酯 烷基侧基 微相分离 耐湿热性能
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某规模化牧场致犊牛腹泻的大肠杆菌分离鉴定及耐药性检测
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作者 曹芳 魏勇 +4 位作者 吴忧 赵鹏飞 陈钊铭 任静静 齐亚银 《中国乳业》 2024年第2期71-75,共5页
[目的]为确定引起石河子某规模化牧场犊牛腹泻的主要病原菌及其耐药情况,并针对犊牛腹泻提出合理应对措施,为该牧场防治犊牛腹泻提供参考。[方法]本研究采取现场流行病学检查,无菌采集15份犊牛腹泻病料,对其进行病原菌分离纯化;通过生... [目的]为确定引起石河子某规模化牧场犊牛腹泻的主要病原菌及其耐药情况,并针对犊牛腹泻提出合理应对措施,为该牧场防治犊牛腹泻提供参考。[方法]本研究采取现场流行病学检查,无菌采集15份犊牛腹泻病料,对其进行病原菌分离纯化;通过生化试验以及分子生物学鉴定,确定致犊牛腹泻的病原菌;对病原菌进行药敏试验,确定耐药情况。[结果]经生化试验以及分子生物学鉴定发现,15份犊牛腹泻病料中,有12份分离到了大肠杆菌。药敏试验结果显示,13株大肠杆菌对链霉素耐药率最高为46.15%(6/13),对青霉素、氨苄西林耐药率为38.46%(5/13),且敏感菌株多为中低敏;对四环素敏感性为76.92%(10/13),13株菌株对头孢噻肟和万古霉素敏感性最高,为84.62%(11/13),多数菌株为多重耐药菌株。[结论]本研究针对腹泻犊牛进行病原菌分离鉴定、药敏试验,为该牧场犊牛腹泻诊治提供参考。 展开更多
关键词 犊牛腹泻 大肠杆菌 分离鉴定 耐药性
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先简支后桥面板连续体系桥面板抗裂性能研究
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作者 刘安 彭天波 +4 位作者 闫博洋 习明星 胡成志 林昱 林道锦 《结构工程师》 2024年第3期107-117,共11页
先简支后桥面板连续体系是一种新型钢混组合结构,在该体系的中支点处设置一定长度的钢梁-混凝土桥面板分离段,可以改善桥面板负弯矩区的受力状态。目前对于该体系桥面板负弯矩区这一薄弱环节的试验研究尚属空白。本研究首先根据实际一... 先简支后桥面板连续体系是一种新型钢混组合结构,在该体系的中支点处设置一定长度的钢梁-混凝土桥面板分离段,可以改善桥面板负弯矩区的受力状态。目前对于该体系桥面板负弯矩区这一薄弱环节的试验研究尚属空白。本研究首先根据实际一座先简支后桥面板连续的钢混组合梁桥,设计制作了两跨1/4比例的缩尺模型,并通过安装、拆除带套筒剪力钉对中支点处的分离段长度进行调节。然后通过在两跨桥面上模拟单轮重轴荷载进行逐点加载试验,研究了分离段长度对桥面板受力状态和抗裂性能的影响。最后对原桥的抗裂性能进行了分析。结果表明,中支点处设置分离段的先简支后桥面板连续体系可显著改善结构的抗裂性能。本研究有助于推广先简支后桥面板连续体系在钢混组合结构中的应用、推动桥梁结构预制装配技术的发展。 展开更多
关键词 钢混组合结构 先简支后桥面板连续 抗裂性能 分离段长度 最不利位置
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一例猪源性金黄色葡萄球菌的分离鉴定与药物敏感性试验
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作者 张鑫 赵东辉 +5 位作者 李杰 贾伟娟 刘志林 贾泽林 崔佳宇 王学理 《中国农学通报》 2024年第23期148-152,共5页
本研究旨在鉴定和分析锦州某猪场病死猪脏器中分离出的一株病原菌,以期为该细菌病的临床诊治提供科学依据。通过LB琼脂培养进行革兰氏染色,BP特殊培养基培养、药物敏感性试验、16S rDNA测序及小鼠致病性试验,并制作病理组织切片进行观... 本研究旨在鉴定和分析锦州某猪场病死猪脏器中分离出的一株病原菌,以期为该细菌病的临床诊治提供科学依据。通过LB琼脂培养进行革兰氏染色,BP特殊培养基培养、药物敏感性试验、16S rDNA测序及小鼠致病性试验,并制作病理组织切片进行观察。由革兰氏染色镜检结果可知该菌为革兰氏阳性球菌;BP培养皿可见黑色菌落生长及菌落周边透明圈;药敏试验表明该菌对恩诺沙星、氧氟沙星、阿米卡星和卡那霉素非常敏感;经16S rDNA测序,该菌和金黄色葡萄球菌16S rDNA片段相似性高;镜检观察病理切片,可见各组织脏器有明显病理损害。该猪场致病菌经分离鉴定为金黄色葡萄球菌,对部分抗生素产生耐药,小鼠攻毒试验具有一定的致病性。 展开更多
关键词 金黄色葡萄球菌 分离鉴定 耐药性 药物敏感性试验 16S rDNA测序
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