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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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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 Modellntermolecular INTERACTIONS AFM
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Fouling-resistant Composite Membranes for Separation of Oil-in-water Microemulsions 被引量:8
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作者 王枢 褚良银 陈文梅 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2006年第1期37-45,共9页
Fouling-resistant ceramic-supported polymer composite membranes were developed for removal of oil-in-water (O/W) microemulsions. The composite membranes were featured with an asymmetric three-layer structure, i.e., a ... Fouling-resistant ceramic-supported polymer composite membranes were developed for removal of oil-in-water (O/W) microemulsions. The composite membranes were featured with an asymmetric three-layer structure, i.e., a porous ceramic membrane substrate, a polyvinylidene fluoride (PVDF) ultrafiltration sub-layer, and a polyam-ide/polyvinyl alcohol (PVA) composite thin top-layer. The PVDF polymer was cast onto the tubular porous ceramic membranes with an immersion precipitation method, and the polyamide/PVA composite thin top-layer was fabricated with an interfacial polymerization method. The effects of the sub-layer composition and the recipe in the interfacial po-lymerization for fabricating the top-layer on the structure and performance of composite membranes were systematically investigated. The prepared composite membranes showed a good performance for treating the O/W microemulsions with a mean diameter of about 2.4μm. At the operating pressure of 0.4MPa, the hydraulic permeability remained steadily about 190L?m-2?h-1, the oil concentration in the permeate was less than 1.6mg·L-1, and the oil rejection coefficient was always higher than 98.5% throughout the operation from the beginning. 展开更多
关键词 W/O分离 微乳液 抗污染复合膜 聚合
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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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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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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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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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尿液中药物与耐药污染及削减技术研究进展
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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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防火分隔用玻璃构件水击试验研究
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作者 徐文飞 郭战胜 王振祥 《消防科学与技术》 CAS 北大核心 2024年第4期482-486,共5页
玻璃构件广泛应用于大型商业综合体,作为防火分隔使用。火灾发生后,消防员灭火救援过程中水击行为可能造成玻璃构件的损坏,造成火灾的蔓延。为了评价水击对受火后的玻璃构件的破坏性,本文结合玻璃构件耐火性能测试,按照建筑构件的标准... 玻璃构件广泛应用于大型商业综合体,作为防火分隔使用。火灾发生后,消防员灭火救援过程中水击行为可能造成玻璃构件的损坏,造成火灾的蔓延。为了评价水击对受火后的玻璃构件的破坏性,本文结合玻璃构件耐火性能测试,按照建筑构件的标准水击方法,开展4次玻璃构件耐火测试后的水击测试。研究表明:4次水击试验,1次玻璃构件耐火性能合格,水击试验未破坏;1次玻璃构件耐火性能合格,水击导致玻璃破裂;2次玻璃构件失去隔热性,水击超温区域瞬间破裂。因此,玻璃构件耐火性能测试后,水击试验可能破坏玻璃构件的完整性,导致防火分隔功能的丧失,玻璃构件耐火试验后有必要进行水冲击测试。 展开更多
关键词 玻璃构件 防火分隔 耐火性能 水击
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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
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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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涂胶隔膜对锂离子电池性能的影响
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作者 刘中奎 陈峰 《电池》 CAS 北大核心 2024年第2期213-216,共4页
以3 Ah软包装动力锂离子电池为研究对象,考察喷涂和辊涂水系涂胶(聚偏氟乙烯及其共聚物)隔膜对电池性能的影响。水系喷涂涂胶隔膜电池具有较低的分容内阻和脉冲充放电直流内阻(DCR)。以不低于2.00 C倍率在2.50~4.25 V充放电,与辊涂涂胶... 以3 Ah软包装动力锂离子电池为研究对象,考察喷涂和辊涂水系涂胶(聚偏氟乙烯及其共聚物)隔膜对电池性能的影响。水系喷涂涂胶隔膜电池具有较低的分容内阻和脉冲充放电直流内阻(DCR)。以不低于2.00 C倍率在2.50~4.25 V充放电,与辊涂涂胶隔膜电池相比,喷涂涂胶隔膜电池的倍率充电恒流充入比高约1%,倍率放电容量比高约0.2%,-20℃放电容量与25℃的容量比低3%以上。25℃和45℃下循环1000次,两种涂胶隔膜性能差异较小;在25℃循环超过1000次,喷涂涂胶隔膜电池性能稍好,循环2000次的容量保持率高约1.7%。 展开更多
关键词 涂胶隔膜 喷涂 辊涂 内阻 循环 锂离子电池 动力电池
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奶牛乳腺炎中凝固酶阴性葡萄球菌的分离鉴定及耐药性分析
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作者 岳丽莎 武岳 +3 位作者 吕雅琼 何一平 李嵩 樊俊铭 《中国奶牛》 2024年第7期51-55,共5页
为减少兽用抗菌药的使用,建立适用于牧场特色的凝固酶阴性葡萄球菌(CNS)乳腺炎奶牛的精准用药方案,对采集自内蒙古呼和浩特市某规模化牛场的262份乳腺炎乳样,采用鉴别显色培养基分离、传统培养和16S rRNA核酸序列鉴定等,对乳腺炎致病菌... 为减少兽用抗菌药的使用,建立适用于牧场特色的凝固酶阴性葡萄球菌(CNS)乳腺炎奶牛的精准用药方案,对采集自内蒙古呼和浩特市某规模化牛场的262份乳腺炎乳样,采用鉴别显色培养基分离、传统培养和16S rRNA核酸序列鉴定等,对乳腺炎致病菌菌种进行分析;后续对分离得到的53株CNS,进行了6种常用药物的MIC试验(微量肉汤稀释法)并分析其耐药性。结果表明,262份乳腺炎样品分离鉴定的致病菌种类丰富,共有20个属,54个种,葡萄球菌属是262个分离株的优势菌属,也是鉴别显色培养基上葡萄球菌区的优势菌属;分析表明CNS可能是长期导致牛场奶牛乳腺炎的主要致病菌。药敏试验结果显示,53株CNS在6种抗菌药物中,对头孢氨苄和马波沙星的耐药率较高,分别为47.17%和49.06%,对头孢噻呋的耐药率最低,为16.98%;在四种β-内酰胺类药物中,对头孢噻呋的敏感性是最高的,达到83.02%,头孢噻呋较头孢喹肟的CNS抗菌活性更好。本次研究分离得到的CNS中,分离株最多的是产色葡萄球菌,对青霉素和头孢噻呋的耐药率较低;其次是模仿葡萄球菌,对头孢噻呋的耐药率最低;溶血葡萄球菌对头孢噻呋和头孢喹肟耐药率较低;松鼠葡萄球菌对头孢氨苄、青霉素和头孢噻呋的耐药率较低。表明不同的CNS菌种对不同的抗生素的敏感性相差较大。本研究为该地区奶牛乳腺炎的管理和防治提供了科学依据。 展开更多
关键词 奶牛乳腺炎 凝固酶阴性葡萄球菌 分离鉴定 耐药性 16S rDNA
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鹅源大肠杆菌的分离鉴定与耐药性分析
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作者 刘畅 刘海月 +5 位作者 郭晶 陈姝霖 李佳美 周铁忠 刘英姿 刘丽颖 《现代畜牧兽医》 2024年第6期63-66,共4页
为明确鹅大肠杆菌的耐药性,试验于2020—2022年采集辽宁各地规模鹅场鹅体液和泄殖腔拭子等样品,采用分离培养、形态观察、生化试验及分子生物学方法对分离株进行鉴定,用微量稀释法对分离株进行药物敏感性测定。结果显示,从110份样品中... 为明确鹅大肠杆菌的耐药性,试验于2020—2022年采集辽宁各地规模鹅场鹅体液和泄殖腔拭子等样品,采用分离培养、形态观察、生化试验及分子生物学方法对分离株进行鉴定,用微量稀释法对分离株进行药物敏感性测定。结果显示,从110份样品中分离获得60株鹅大肠杆菌,分离株对阿莫西林、氨苄西林耐药率高于90%,对复方新诺明、恩诺沙星、氟苯尼考、氧氟沙星的耐药率高于30%,而对克拉维酸、庆大霉素、大观霉素、磺胺异恶唑、土霉素耐药率较低,对多黏菌素B高度敏感。研究表明,辽宁地区分离的鹅大肠杆菌对上述大部分抗菌药物耐药率较高。因此,应通过科学饲养和生物安全管理增强机体抵抗力,减少病原感染,同时科学使用敏感抗生素,使鹅大肠杆菌病得以有效控制并避免菌株耐药性的产生和传播。 展开更多
关键词 大肠杆菌 分离鉴定 耐药性
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Oil–water pre-separation with a novel axial hydrocyclone 被引量:13
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作者 Meili Liu Jiaqing Chen +2 位作者 Xiaolei Cai Yanhe Han Si Xiong 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2018年第1期60-66,共7页
A novel hydrocyclone with guide vanes, named as axial hydrocyclone(AHC), is designed to tackle the problem of oil–water separation faced by most mature oilfields. Optimal design of the AHC is carried out by using num... A novel hydrocyclone with guide vanes, named as axial hydrocyclone(AHC), is designed to tackle the problem of oil–water separation faced by most mature oilfields. Optimal design of the AHC is carried out by using numerical methods. The effects of guide vanes, cone angle, tapered angle and overflow pipe on the oil–water separation are discussed in this paper. The results show that a double swirling flow is generated in the tapered section where oil–water separation occurs. Both the cylindrical and the tapered section have important influences on AHC performance. On the basis of single factor results, response surface methodology is employed to optimize the AHC design. The experimental results indicate that the novel AHC has an excellent performance for the oil–water separation. 展开更多
关键词 油水分离 样轴 设计处理 数字方法 方法论 试验性 指南 油矿
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黄帚橐吾乙醇提取物对黏虫毒力及其解毒酶系活性的影响
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作者 李晶 李娜 +5 位作者 付麟雲 刘锦霞 丁品 张建军 武建荣 王萍 《杂草学报》 2023年第1期11-17,共7页
黏虫(Mythimna separata)是典型的杂食性迁飞性农业害虫,每年都给我国的农业生产造成极大的经济损失。测定黄帚橐吾(Ligularia virgaurea)乙醇提取物对黏虫幼虫的毒力,并从细胞色素P450(CYP450)、谷胱甘肽-S-转移酶(GST)、羧酸酯酶(CarE... 黏虫(Mythimna separata)是典型的杂食性迁飞性农业害虫,每年都给我国的农业生产造成极大的经济损失。测定黄帚橐吾(Ligularia virgaurea)乙醇提取物对黏虫幼虫的毒力,并从细胞色素P450(CYP450)、谷胱甘肽-S-转移酶(GST)、羧酸酯酶(CarE)、酸性磷酸酯酶(ACP)和碱性磷酸酯酶(ALP)等解毒酶系活性的角度研究黏虫幼虫对该药物的生理生化响应。结果表明,黄帚橐吾乙醇提取物对黏虫幼虫有较强的生物活性,LC_(50)为3.655 mg/mL;CYP450活性在前8 h略有上升,12 h后显著降低(P<0.05);GST活性在4 h时被显著激活,随后受到极显著抑制(P<0.01);3种酯酶活性整体表现出逐渐降低的趋势。上述酶活性变化表明CYP450和GST可能参与了黏虫对黄帚橐吾提取物的代谢过程,但其最终被显著抑制的结果提示黄帚橐吾源农药较难使黏虫产生抗药性,具备被开发成为新型生物农药的潜力。 展开更多
关键词 黄帚橐吾 生物农药 黏虫 代谢酶活性 抗药性 毒力
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棉铃虫围食膜中Bt抗性相关蛋白的分离与鉴定
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作者 李怡萍 刘少凯 +1 位作者 袁向群 郭予元 《植物保护》 CAS CSCD 北大核心 2023年第1期132-138,共7页
棉铃虫是世界性的重要农业害虫。围食膜作为昆虫抵御病原微生物入侵及有害物质的第一道天然保护性屏障,其上可能存在与Bt抗性相关的受体蛋白。本研究以Bt Cry1Ac抗性和敏感品系的棉铃虫围食膜为对象,采用NuPAGE电泳技术、配体杂交、质... 棉铃虫是世界性的重要农业害虫。围食膜作为昆虫抵御病原微生物入侵及有害物质的第一道天然保护性屏障,其上可能存在与Bt抗性相关的受体蛋白。本研究以Bt Cry1Ac抗性和敏感品系的棉铃虫围食膜为对象,采用NuPAGE电泳技术、配体杂交、质谱鉴定和生物信息学分析等技术,测定了围食膜蛋白含量,鉴定了蛋白质的组成及与Bt Cry1Ac毒素的结合能力。结果表明敏感品系围食膜中蛋白含量为22.19%,抗性品系围食膜中蛋白含量为26.99%。抗、感品系棉铃虫围食膜上存在与Cry1Ac毒素结合的6个差异蛋白,推测其中棉铃虫羧酸酯酶蛋白和血影蛋白是2个有意义的抗性相关蛋白,2个新蛋白可能参与Bt抗性。研究证明棉铃虫围食膜上存在Bt结合蛋白且与抗性相关,为进一步明确Bt抗性机制、制定合理的Bt抗性治理策略提供了理论依据。 展开更多
关键词 棉铃虫 围食膜蛋白 Bt抗性 分离与鉴定
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