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冷冻原肠中细菌基因组DNA提取方法的建立 预览
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作者 宋鸿雁 仇保丰 +4 位作者 高雪梅 刘春 刘文斌 朱顺星 邵义祥 《中国动物检疫》 CAS 2020年第2期87-93,共7页
为建立冷冻原肠中细菌基因组DNA的直接提取法,采用震荡洗脱、金属网过滤和梯度离心相结合的方法,对2份冷冻原肠样品进行前处理;对经前处理后的原肠样品,采用酚/氯仿法提取细菌基因组DNA,然后进行琼脂糖电泳和OD260/OD280比值测定;以细... 为建立冷冻原肠中细菌基因组DNA的直接提取法,采用震荡洗脱、金属网过滤和梯度离心相结合的方法,对2份冷冻原肠样品进行前处理;对经前处理后的原肠样品,采用酚/氯仿法提取细菌基因组DNA,然后进行琼脂糖电泳和OD260/OD280比值测定;以细菌基因组DNA为模板,用PCR技术扩增细菌16S rDNA并构建克隆文库,并从2个文库中各随机挑取3个菌落进行16S rDNA的PCR鉴定和DNA测序。结果显示:样品提取的DNA浓度、纯度较高,OD260/OD280比值介于1.8~2.0;挑取的6个菌落中,1个为阴性,剩余5个为阳性,为肠球菌属(Enterococcus)和魏斯氏菌属(Weissella)的5种细菌。结果表明,本研究提取的原肠细菌基因组DNA质量较好,可用于非培养法研究冷冻原肠中细菌的多样性。本研究解决了因缺乏原肠细菌基因组DNA提取方法,无法进一步应用现代分子生物学方法研究冷冻原肠细菌的多样性、菌群组成结构和动态变化等难题。 展开更多
关键词 冷冻原肠 细菌 细菌基因组DNA 提取方法
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159例烧伤重症监护病房导管相关性血流感染患者病原菌分布及耐药性分析
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作者 罗小强 龚雅利 +4 位作者 张成 刘美希 石云龙 彭毅志 黎宁 《中华烧伤杂志》 CAS CSCD 北大核心 2020年第1期24-31,共8页
目的分析烧伤重症监护病房(ICU)导管相关性血流感染(CRBSI)患者病原菌分布与耐药情况。方法2011年1月—2018年12月,陆军军医大学(第三军医大学)第一附属医院(下称笔者单位)烧伤ICU收治患者中有2264例行中心静脉导管置管,其中159例发生CR... 目的分析烧伤重症监护病房(ICU)导管相关性血流感染(CRBSI)患者病原菌分布与耐药情况。方法2011年1月—2018年12月,陆军军医大学(第三军医大学)第一附属医院(下称笔者单位)烧伤ICU收治患者中有2264例行中心静脉导管置管,其中159例发生CRBSI[男131例、女28例,年龄43(1,79)岁],收集CRBSI患者从外周静脉血及中心静脉导管血/中心静脉置管前段标本初次分离的病原菌进行以下回顾性分析。采用API微生物鉴定试剂盒和全自动微生物鉴定仪进行病原菌鉴定,采用微量肉汤稀释法或K-B纸片扩散法检测病原菌对氟康唑、伊曲康唑等5种抗真菌药物和替加环素、亚胺培南等37种抗细菌药物的耐药情况,采用改良Hodge试验进一步确认亚胺培南、美罗培南耐药肺炎克雷伯菌,采用D试验检测金黄色葡萄球菌对红霉素诱导克林霉素耐药情况。采用WHONET 5.6软件统计分析各年度CRBSI发生率,CRBSI患者病死率,CRBSI例次发生率及感染部位分布与置管持续时间,革兰阴性菌、革兰阳性菌、真菌及耐甲氧西林金黄色葡萄球菌(MRSA)、甲氧西林敏感金黄色葡萄球菌(MSSA)检出情况,常见革兰阴性菌、革兰阳性菌及真菌对临床常用抗菌药物的耐药情况。结果(1)8年间,CRBSI发生率为7.0%(159/2264),其中2014、2017年CRBSI发生率略高,分别为13.6%(30/221)、11.1%(24/217)。CRBSI患者病死率为7.5%(12/159)。(2)CRBSI例次发生率为14.9%(338/2264);感染部位以股静脉为主,共271例次(80.2%),该部位置管持续时间为9(2,25)d。(3)8年间,共检出病原菌543株,其中革兰阴性菌353株,占65.0%;革兰阳性菌140株,占25.8%;真菌50株,占9.2%。检出率居前3位的病原菌从高到低依次为鲍氏不动杆菌、金黄色葡萄球菌和铜绿假单胞菌,分别占23.2%(126/543)、17.1%(93/543)和15.7%(85/543);真菌以近平滑念珠菌为主。金黄色葡萄球菌中,MRSA占98.9%(92/93)、MSSA占1.1%(1/93)。(4)鲍氏不动杆菌除对 展开更多
关键词 烧伤 感染 细菌 真菌 抗药性 导管相关性血流感染
巨杉健康和感病叶片表面微生物组成和多样性比较 预览
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作者 岳雪华 范深厚 +3 位作者 杜雪柯 胡嘉琪 张扬 李媛媛 《福建农林大学学报:自然科学版》 CSCD 北大核心 2020年第1期10-17,共8页
为分析巨杉(Sequoiadendron giganteum)健康叶片和感病叶片表面微生物的组成和多样性异同,以我国引种的巨杉叶片表面微生物类群为研究对象,采用高通量测序对细菌16S rRNA和真菌ITS片段测序,通过OTU数量、多样性指数、鉴定类群等方法,分... 为分析巨杉(Sequoiadendron giganteum)健康叶片和感病叶片表面微生物的组成和多样性异同,以我国引种的巨杉叶片表面微生物类群为研究对象,采用高通量测序对细菌16S rRNA和真菌ITS片段测序,通过OTU数量、多样性指数、鉴定类群等方法,分析叶片表面细菌和真菌组成和多样性的异同.结果表明,健康叶片表面的细菌多样性比感病叶片高,但肠杆菌属(Enterobacter)、金黄杆菌属(Chryseobacterium)和短小杆菌属(Curtobacterium)菌群的含量在感病叶片中占所有细菌群落的比例比健康叶片高;真菌类群在健康叶片表面的多样性比感病叶片丰富,其中葡萄孢属(Botrytis)的卡罗来纳葡萄孢(B.caroliniana)占感病叶片表面真菌总数量的49.60%,远远多于健康叶片所占比例16.10%.健康叶片比感病叶片表面维持了较高的细菌和真菌类群多样性,卡罗来纳葡萄孢真菌在感病叶片表面所占比例远远大于健康叶片,可能与植株感病有关,此结果可为巨杉致病菌的防治提供依据. 展开更多
关键词 巨杉 细菌 真菌 多样性 致病微生物
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湖南省某规模场育肥猪多种病原混合感染的诊断及防控 预览
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作者 张古月 罗灵芝 +3 位作者 龙剑 谢怡灵 廖荣莉 李润成 《中国动物检疫》 CAS 2020年第2期71-76,共6页
湖南省某规模猪场的保育猪在转至育肥舍10 d后(约80日龄)陆续出现发病死亡情况。为确诊病情,查找病因,采集不同年龄段的猪血清进行猪瘟病毒(CSFV)、猪繁殖与呼吸综合征病毒(PRRSV)、圆环病毒2型(PCV2)抗体检测,同时对4头发病猪进行剖检... 湖南省某规模猪场的保育猪在转至育肥舍10 d后(约80日龄)陆续出现发病死亡情况。为确诊病情,查找病因,采集不同年龄段的猪血清进行猪瘟病毒(CSFV)、猪繁殖与呼吸综合征病毒(PRRSV)、圆环病毒2型(PCV2)抗体检测,同时对4头发病猪进行剖检观察,并采集病料进行CSFV、PRRSV、PCV2病原检测以及细菌分离、药敏分析。结果显示:疫病发生前后的生猪CSFV抗体均不理想,无高抗体水平个体出现,但病原检测为阴性;生猪PRRSV、PCV2抗体整体上均经历了母源抗体下降、发病时抗体又上升的阶段,且病原检测均有阳性样本存在;在病料中分离到葡萄球菌、链球菌、副猪嗜血杆菌。由此推断,该次生猪发病原因可能为PRRSV、PCV2以及多种细菌的混合感染。结合病因推测,制定了防治方案,并有效控制了病情,也验证了此次发病的原因推断。本起疫情的诊断和防治为猪场多病原混合感染防控提供了参考,也提示规模猪场需要开展疫病的综合防控。 展开更多
关键词 猪繁殖与呼吸综合征病毒 猪圆环病毒2型 细菌 混合感染 诊断 防控措施
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饲粮非纤维性碳水化合物/中性洗涤纤维对卡拉库尔羊营养物质消化和瘤胃菌群结构的影响 预览
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作者 普宣宣 郭雪峰 +3 位作者 蒋辰宇 刘俊峰 张秀萍 张苏江 《动物营养学报》 CAS CSCD 北大核心 2020年第1期285-294,共10页
本试验旨在研究饲粮非纤维性碳水化合物/中性洗涤纤维(NFC/NDF)对卡拉库尔羊营养物质消化率和瘤胃菌群结构的影响。试验选取18月龄、体况良好、体重[(35.0±3.3)kg]相近、装有永久性瘤胃瘘管的卡拉库尔羊(去势公羊)12只,随机分为4组... 本试验旨在研究饲粮非纤维性碳水化合物/中性洗涤纤维(NFC/NDF)对卡拉库尔羊营养物质消化率和瘤胃菌群结构的影响。试验选取18月龄、体况良好、体重[(35.0±3.3)kg]相近、装有永久性瘤胃瘘管的卡拉库尔羊(去势公羊)12只,随机分为4组,每组3只,分别饲喂4种饲粮,饲粮NFC/NDF分别为0.54(1组)、0.96(2组)、1.37(3组)、1.90(4组)。试验分为4期,Ⅰ期(1~26 d)、Ⅱ期(27~52 d)、Ⅲ期(53~78 d)和Ⅳ期(79~104 d)。试验每期均为预试期15 d,正试期11 d,其中消化试验8 d,瘤胃内容物收取3 d。各期均测定营养物质表观消化率和瘤胃菌群结构。结果表明:1)4期试验中,3组和4组干物质(DM)表观消化率显著高于1组和2组(P<0.05),有机物(OM)表观消化率除Ⅰ期3组和4组显著高于1组和2组(P<0.05)外,其余3期组间差异均不显著(P>0.05),NDF和酸性洗涤纤维(ADF)表观消化率均为3组最高,但组间差异不显著(P>0.05)。2)4期试验中,2组瘤胃菌群结构均与1组、3组和4组差异较大,不同时期同组的菌群结构分布相对集中。纤维降解菌属、半纤维降解菌属和淀粉降解菌属的相对丰度分别在2组、3组和4组达到最高。由此可知,饲粮NFC/NDF为1.37时,可提高营养物质消化率;NFC/NDF为0.96时,菌群结构改变较大,同组饲粮菌群结构未随试验期数发生太大改变;4期试验中,纤维降解菌、半纤维降解菌和淀粉降解菌在属水平上的相对丰度分别在NFC/NDF为0.96、1.37和1.90时达到最高。 展开更多
关键词 NFC/NDF 表观消化率 细菌 卡拉库尔羊
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微生物源类胡萝卜素的研究进展 预览
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作者 邓永平 段睿 +2 位作者 王晓杰 艾瑞波 刘晓兰 《饲料工业》 北大核心 2020年第1期12-17,共6页
类胡萝卜素可以增强动物免疫力、提高产品质量,在动物养殖中应用越来越广泛。微生物是天然类胡萝卜素的主要来源。文章对微生物源天然类胡萝卜素的研究现状进行了综述,同时提出了未来的发展方向,为产率高、经济可行的微生物法制备类胡... 类胡萝卜素可以增强动物免疫力、提高产品质量,在动物养殖中应用越来越广泛。微生物是天然类胡萝卜素的主要来源。文章对微生物源天然类胡萝卜素的研究现状进行了综述,同时提出了未来的发展方向,为产率高、经济可行的微生物法制备类胡萝卜素提供基础。 展开更多
关键词 微藻 真菌 细菌 类胡萝卜素 综述
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基于Illumina MiSeq测序技术不同地区辣椒酱细菌多样性分析 预览
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作者 宁明 赵馨馨 +4 位作者 董蕴 倪慧 单春会 张振东 郭壮 《中国调味品》 CAS 北大核心 2020年第2期58-63,共6页
在采用MiSeq高通量测序技术对咸丰地区10个辣椒酱细菌群落多样性进行系统分析的基础上,进一步从MG-RAST数据中下载当阳地区辣椒酱测序数据,进而对不同地区辣椒酱核心细菌类群进行比较分析。结果表明,咸丰地区辣椒酱中核心细菌类群主要由... 在采用MiSeq高通量测序技术对咸丰地区10个辣椒酱细菌群落多样性进行系统分析的基础上,进一步从MG-RAST数据中下载当阳地区辣椒酱测序数据,进而对不同地区辣椒酱核心细菌类群进行比较分析。结果表明,咸丰地区辣椒酱中核心细菌类群主要由Lactobacillus,Bacillus,Leuconostoc,Pediococcus,Weissella,Pseudomonas,Halomonas和Corynebacterium构成。基于UniFrac距离的主坐标分析和聚类分析均表明,咸丰和当阳地区辣椒酱细菌群落结构存在较大差异,咸丰地区辣椒酱细菌群落结构种类多样性及丰度要显著偏高(p<0.05)。该研究对揭示辣椒酱细菌多样性和不同地区间差异的关联性可能具有一定积极意义。 展开更多
关键词 辣椒酱 高通量测序 多样性 细菌 比较分析
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污泥厌氧消化功能微生物群落结构的研究进展 预览
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作者 唐涛涛 李江 +3 位作者 杨钊 向福亮 王跃虎 李彦澄 《化工进展》 EI CAS CSCD 北大核心 2020年第1期320-328,共9页
污泥厌氧消化处理技术因其具有无害化、资源化和稳定化的特征备受关注。污泥厌氧消化涉及水解发酵、产氢产乙酸和产甲烷多种微生物,并发挥不同的功能。本文介绍了污泥厌氧消化体系中常见的细菌(门水平)和古菌(属水平)群落,如拟杆菌门(Ba... 污泥厌氧消化处理技术因其具有无害化、资源化和稳定化的特征备受关注。污泥厌氧消化涉及水解发酵、产氢产乙酸和产甲烷多种微生物,并发挥不同的功能。本文介绍了污泥厌氧消化体系中常见的细菌(门水平)和古菌(属水平)群落,如拟杆菌门(Bacteroidetes)、变形菌门(Proteobacteria)、厚壁菌门(Firmicutes)、绿弯菌门(Chloroflexi)、螺旋体门(Spirochaetes)(细菌)和甲烷杆菌属(Methanobacterium)、甲烷八叠球菌属(Methanosarcina)、甲烷短杆菌属(Methanobrevibacter)、鬃毛甲烷菌属(Methanosaeta)(古菌)等。同时也综述了影响厌氧体系中的微生物群落结构的因素,如pH、营养物质、温度、氨氮(NH4+-N)及有毒有害物质等。最后展望了稳定同位素标记、宏基因组学和蛋白质组学等分子生物技术在探查微生物功能方面的应用前景,为进一步分析厌氧体系中未识别的功能微生物提供技术支撑。 展开更多
关键词 厌氧消化 功能微生物 细菌 古菌
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早产儿重症监护病房实验室确诊败血症病原分布及临床特点 预览
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作者 常淑婷 刘新晖 +4 位作者 李强 马金霞 庄严 高喜容 谭李红 《中国感染控制杂志》 CAS CSCD 北大核心 2020年第1期37-41,共5页
目的调查重症监护病房败血症早产儿病原菌分布及其临床特点。方法回顾性分析2016年1月—2018年12月某院早产儿重症监护病房收治的血培养阳性,实验室确诊败血症155例,对不同病原菌早产儿败血症临床特点进行比较。结果155例早产儿败血症中... 目的调查重症监护病房败血症早产儿病原菌分布及其临床特点。方法回顾性分析2016年1月—2018年12月某院早产儿重症监护病房收治的血培养阳性,实验室确诊败血症155例,对不同病原菌早产儿败血症临床特点进行比较。结果155例早产儿败血症中,革兰阴性(G-)杆菌组76例(占49.03%),以肺炎克雷伯菌败血症为主;革兰阳性(G+)球菌组42例(占27.10%),以表皮葡萄球菌败血症为主;真菌组37例(占23.87%),以近平滑假丝酵母菌、白假丝酵母菌败血症为主。G-菌组和真菌组早产儿胎龄、出生体重小于G+菌败血症组;真菌败血症组早产儿起病日龄大于G-菌组、G+菌组,深静脉置管比例高于G-菌组、G+菌组;真菌组早产儿血小板计数低于G-菌、G+菌组;G-菌组C反应蛋白(CRP)高于G+菌组和真菌组,差异均有统计学意义(均P<0.05)。155例早产儿治愈好转率94.84%,病死率5.16%。G-菌组患儿病死率高于G+菌组、真菌组,真菌败血症组治疗日数长于G-菌、G+菌组,差异均有统计学意义(均P<0.05)。结论早产儿败血症致病菌主要为G-菌,G-菌组、G+菌组及真菌组败血症早产儿临床表现不同、实验室指标及预后不同。 展开更多
关键词 败血症 脓毒症 细菌 真菌 新生儿 早产
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基于微生物矿物沉积的混凝土开裂自愈合 预览
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作者 闫睿 赵胤 +2 位作者 杨豪 李佳鹏 刘瑶 《山西建筑》 2020年第3期90-91,共2页
为了保护存在于混凝土中的高碱环境中的细菌,采用吸水性强的沸石做载体;基于微生物的矿化理论,利用微生物技术对开裂混凝土进行自修复。水泥砂浆开裂自愈合的研究结果表明:开裂龄期为28 d时,对于含有和不含愈合剂的样品,修复效果存在显... 为了保护存在于混凝土中的高碱环境中的细菌,采用吸水性强的沸石做载体;基于微生物的矿化理论,利用微生物技术对开裂混凝土进行自修复。水泥砂浆开裂自愈合的研究结果表明:开裂龄期为28 d时,对于含有和不含愈合剂的样品,修复效果存在显著差异,掺有愈合剂的样品,宽度在0.1 mm以内的裂缝能够完全修复。 展开更多
关键词 水泥砂浆 细菌 载体 自愈合
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单中心PICU细菌分布特点分析 预览
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作者 李奔 陈瑜 +6 位作者 陈中举 熊鹏 袁义 黄浩 张文迪 付丽娜 刘铜林 《华中科技大学学报:医学版》 CAS CSCD 北大核心 2019年第5期585-589,612共6页
目的分析儿童重症监护室(PICU)常见细菌分布特点,为临床早期合理使用抗生素提供依据。方法回顾性研究2013年1月1日~2017年12月31日华中科技大学同济医学院附属同济医院儿童重症监护室微生物培养病原菌检测结果,统计分析该PICU常见病原... 目的分析儿童重症监护室(PICU)常见细菌分布特点,为临床早期合理使用抗生素提供依据。方法回顾性研究2013年1月1日~2017年12月31日华中科技大学同济医学院附属同济医院儿童重症监护室微生物培养病原菌检测结果,统计分析该PICU常见病原菌的分布特点。结果①PICU常见细菌:14101份送检标本培养出779株非重复细菌,包括革兰阴性菌529株(67.9%),革兰阳性菌250株(32.1%)。常见病原菌依次为肺炎克雷伯菌129株(16.6%)、不动杆菌属110株(14.1%)、金黄色葡萄球菌93株(11.9%)、大肠埃希菌66株(8.5%)、肺炎链球菌57株(7.3%)等。②影响细菌分布的因素:痰培养、导管尖端培养及皮肤分泌物培养以检出革兰阴性菌为主,而血培养、尿培养及脑脊液培养以检出革兰阳性菌为主。肺炎克雷伯菌及大肠埃希菌感染好发于婴幼儿,金黄色葡萄球菌及肺炎链球菌感染好发于年长儿。随着住院时间的延长,革兰阴性菌检出率上升,而革兰阳性菌检出率下降。结论该院PICU微生物培养总阳性率不高,常见病原菌仍以革兰阴性菌为主。不同标本、不同年龄、不同住院日及不同年份病原菌分布有差异,临床经验性用药应有针对性。 展开更多
关键词 儿童重症监护室 感染性疾病 细菌 革兰阳性菌 革兰阴性菌
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冷鲜鸡肉表面四环素和磺胺耐药菌的菌群多样性分析 预览
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作者 邵毅 姚春霞 +5 位作者 黄柳娟 冯博 周昌艳 白冰 王华 王卫国 《农业工程学报》 EI CAS CSCD 北大核心 2019年第17期301-308,共8页
为探索冷鲜鸡肉产品表面的抗生素耐药菌的菌群结构,利用IonS5^TMXL测序平台对18个市售冷鲜鸡肉样品表面的可培养四环素耐药菌和磺胺耐药菌进行了研究。结果表明,2类耐药菌中分别注释出59个和58个已明确属名的属,相对丰度最大的3个门均... 为探索冷鲜鸡肉产品表面的抗生素耐药菌的菌群结构,利用IonS5^TMXL测序平台对18个市售冷鲜鸡肉样品表面的可培养四环素耐药菌和磺胺耐药菌进行了研究。结果表明,2类耐药菌中分别注释出59个和58个已明确属名的属,相对丰度最大的3个门均为变形菌门、拟杆菌门和厚壁菌门。共享菌属中不动杆菌属、假单胞菌属、变形杆菌属、柠檬酸杆菌属、香味菌属和漫游球菌属的禽源和人源分离株的多重耐药性已被大量研究所证实;而禽源肉杆菌属等16个菌属的耐药特性还未见报道。各采样点分别鉴定出5~39个特有操作分类单元,分属3~32个属。该研究反映了冷鲜鸡肉表面2类耐药菌的污染状况,为后期冷鲜鸡肉产品表面耐药菌的迁移风险评估和控制技术研究提供参考。 展开更多
关键词 微生物 细菌 抗生素 冷鲜鸡 四环素耐药菌 磺胺耐药菌 菌群多样性
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Characterization of CANON reactor performance and microbial community shifts with elevated COD/N ratios under a continuous aeration mode
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作者 Yao Zhang Yayi Wang +2 位作者 Yuan Yan Haicheng Han Min Wu 《中国环境科学与工程前沿:英文版》 SCIE EI CAS CSCD 2019年第1期73-85,共13页
The effects of increasing COD/N on nitrogen removal performance and microbial structure were investigated in a SBR adopting a completely autotrophic nitrogen removal over nitrite process with a continuous aeration mod... The effects of increasing COD/N on nitrogen removal performance and microbial structure were investigated in a SBR adopting a completely autotrophic nitrogen removal over nitrite process with a continuous aeration mode (DO at approximately 0.15-0.2 mg/L). As the COD/N increased from 0.1 to W0.59, the nitrogen removal efficiency QMRE) increased from 88.7% to 95.5%;while at COD/N ratios of 0.59-0.82, the NRE remained at 90.7%-95.5%. As the COD/N increased from 0.82 to 1.07, the NRE decreased continuously until reaching 60.1%. Nitrosomonas sp.(AOB) and Candidatus Jet tenia (anammox bacteria) were the main functional genera in the SBR. As the COD/N increased from 0.10 to 1.07, the relative abundance of Nitrosomonas decreased from 13.4% to 2.0%, while that of Candidatus Jettenia decreased from 35% to 9.9% with COD/N < 0.82 then increased to 45.4% at a COD/N of 1.07. Aerobic heterotrophic bacteria outcompeted AOB at high COD loadings (650 mg/L) because of oxygen competition, which ultimately led to deteriorated nitrogen removal pertormance. 展开更多
关键词 CANON process COD/N ratio Anammox Ammonia oxidizing BACTERIA Aerobic HETEROTROPHIC BACTERIA
Synthesis of Novel 4-Thiazolidinone and Bis-Thiazalidin-4-One Derivatives Derived from 4-Amino-Antipyrine and Evaluated as Inhibition of Purine Metabolism Enzymes by Bacteria 预览
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作者 Reda M. Abdel Rahman Abdulrahman S. Alharbi Nawaa A. Alshammari 《有机化学国际期刊(英文)》 2019年第2期85-95,共11页
Novel 4-thiazolidione and 1,4-bis-thiazolidinone derivatives bearing antipyrine moiety have been obtained from condensation of 4-aminoantipyrine 1 with aromatic/heteroaldehydes followed by cycloaddition with mercaptoa... Novel 4-thiazolidione and 1,4-bis-thiazolidinone derivatives bearing antipyrine moiety have been obtained from condensation of 4-aminoantipyrine 1 with aromatic/heteroaldehydes followed by cycloaddition with mercaptoacetic acid in nonpolar solvents. Structure of the products has been deduced upon their elemental analysis and spectral measurements. Most of the targets evaluated as enzymatic effect towards some bacteria (E. coli) in compare with Xanthine oxidase (from buttermilk) where the role of compounds is an inhibition of purine metabolism enzymes caused by E. coli. 展开更多
关键词 Synthesis 4-Thiazolidinones ANTIPYRINE INHIBITION of Purine Metabolism ENZYMES BACTERIA
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Analysis of cultivable aerobic bacterial community composition and screening for facultative sulfate-reducing bacteria in marine corrosive steel 预览
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作者 LI Xiaohong XIAO Hui +7 位作者 ZHANG Wenjun LI Yongqian TANG Xuexi DUAN Jizhou YANG Zhibo WANG Jing GUAN Fang DING Guoqing 《海洋湖沼学报(英文)》 SCIE CAS CSCD 2019年第2期600-614,共15页
Anaerobic, aerobic, and facultative bacteria are all present in corrosive environments. However, as previous studies to address corrosion in the marine environment have largely focused on anaerobic bacteria, limited a... Anaerobic, aerobic, and facultative bacteria are all present in corrosive environments. However, as previous studies to address corrosion in the marine environment have largely focused on anaerobic bacteria, limited attention has been paid to the composition and function of aerobic and facultative bacteria in this process. For analysis in this study, ten samples were collected from rust layers on steel plates that had been immersed in seawater for diff erent periods (i.e., six months and eight years) at Sanya and Xiamen, China. The cultivable aerobic bacterial community structure as well as the number of sulfate-reducing bacteria (SRB) were analyzed in both cases, while the proportion of facultative SRB among the isolated aerobic bacteria in each sample was also evaluated using a novel approach. Bacterial abundance results show that the proportions are related to sea location and immersion time;abundances of culturable aerobic bacteria (CAB) and SRB from Sanya were greater in most corrosion samples than those from Xiamen, and abundances of both bacterial groups were greater in samples immersed for six months than for eight years. A total of 213 isolates were obtained from all samples in terms of CAB community composition, and a phylogenetic analysis revealed that the taxa comprised four phyla and 31 genera. Bacterial species composition is related to marine location;the results show that Firmicutes and Proteobacteria were the dominant phyla, accounting for 98.13% of the total, while Bacillus and Vibrio were the dominant genera, accounting for 53.06% of the total. An additional sixfacultative SRB strains were also screened from the isolates obtained and were found to encompass the genus Vibrio (four strains), Staphylococcus (one strain), and Photobacterium (one strain). It is noteworthy that mentions of Photobacterium species have so far been absent from the literature, both in terms of its membership of the SRB group and its relationship to corrosion. 展开更多
关键词 MARINE corrosive STEEL cultivable AEROBIC BACTERIA FACULTATIVE sulfate-reducing BACTERIA bacterial community composition 16S rRNA gene SEQUENCING
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Bacteria in Indian Food Packaging Papers and Paperboards with Various Contents of Pulp Fiber 预览
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作者 Swati Sood Chhaya Sharma 《食品与营养科学(英文)》 2019年第4期349-357,共9页
The food packaging industry generally uses papers and paperboards (PPBs) especially for disposable products. According to the Framework Regulation (EC) No. 1935/2004 of the European Union, no transfer of contamination... The food packaging industry generally uses papers and paperboards (PPBs) especially for disposable products. According to the Framework Regulation (EC) No. 1935/2004 of the European Union, no transfer of contamination should occur from food packaging material to the food items. The aim of this study was to determine the presence, numbers, source and different kinds of bacteria present in food packaging PPBs with various contents of pulp fiber. The samples were randomly collected from popular confectioners and fast food restaurants in Saharanpur, India. The results indicated the presence of bacteria in all the samples, ranging from 1.3 × 102 to 6.1 × 103 cfu/g. Most of the samples contained bacteria in more than the permitted concentration of 2.5 × 102 cfu/g as set by Food and Drug Administration (FDA). The detected bacteria were from genera Bacillacea, Staphylococcus and Pseudomonas. According to the FDA declaration, pathogenic bacteria such as B. cereus and S. aureus have been associated with food borne diseases (FBD). Some contaminants in food packaging PPBs were found to be B. subtilis and P. aeroginosa, which produce enzymes like peroxidases and lipoxygenases that are odor generating enzymes. 展开更多
关键词 BACTERIA ODOR Health Safety Food Packaging PAPERS and Paperboards (PPBs) PULP Fiber
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Composition and Molecular Identification of Bacterial Community in Seawater Desalination Plants 预览
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作者 Pilar Garcia-Jimenez Marina Carrasco-Acosta +9 位作者 Carlos Enrique Payá Irina Alemá n Ló pez Juana Rosa Betancort Rodrí guez José Alberto Herrera Meliá n 《微生物学(英文)》 2019年第10期863-876,共14页
Biofouling is an important problem for reverse osmosis (RO) membrane manufacturers. Bacteria are mainly involved in generating fouling and obturating RO membranes. Insights into biofilm bacteria composition could help... Biofouling is an important problem for reverse osmosis (RO) membrane manufacturers. Bacteria are mainly involved in generating fouling and obturating RO membranes. Insights into biofilm bacteria composition could help prevent biofouling, reduce the cost of using RO-fouling membranes and guarantee safe water. Culture-dependent and independent techniques were then performed in order to identify bacteria associated with RO membranes. Bacteria cultures described the presence of six pure colonies, four of which were identified through API testing. Based on 16s rRNA gene analysis, a predominant bacterium was identified and annotated as Sphingomonas sp. The 16s rRNA gene clone library, on the other hand, showed that the bacterium, Pseudomonas marincola, accounted for nearly 30% of the clone library, while the rest of bacteria were chimeras (62%) and non-representative species (3%). In conclusion, culture-dependent and independent approaches showed that two dominant bacteria were commonly observed in RO desalination membranes. 展开更多
关键词 BIOFOULING Bacteria 16s RRNA REVERSE Osmosis Membrane PSEUDOMONAS sp. SPHINGOMONAS sp.
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Tracing of Antibiotic-Resistant Bacteria Isolated from Semen of Iraqi Males with Primary Infertility 预览
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作者 Mohemid M. Al-Jebouri Salih A. Mdish 《泌尿学期刊(英文)》 2019年第1期19-29,共11页
Objectives: The main objective of this study was to investigate the bacterial infections of seminal fluid in males with primary infertility. The patients were referred to and/or visiting the Urology Department in Sala... Objectives: The main objective of this study was to investigate the bacterial infections of seminal fluid in males with primary infertility. The patients were referred to and/or visiting the Urology Department in Salah Al-Deen Teaching Hospital. Methods: The present study was carried out from May 2017 to June 2018 and the number of the patients group was 60. The patients aged between 20 to 50 years. Semen was collected from infertile men of a couple that female failed to become pregnant after one year of regular and unprotected intercourse of marriage and submitted for seminal fluid analysis for the bacteriological analyses. The control group consisted of 50 fertile male who were selected randomly from Tikrit City during the period of this study. Semen culture was done for all the patients and the control group. Results: There were 30 patients who suffered from bacteriospermia and 16 of them (53.3%) were infected with gram positive organisms, while only 14 (46.7%) patients were infected with gram negative organisms. The most common organism was Staphylococcus aureus which was isolated from bacteriospermia. Escherichia coli, Enterococcus faecalis, Klebsiella pneumoniae, S. saprophyticus, Proteus mirabilis and Niesseria gonorrhoae were also isolated and the frequencies of isolation were 23.3% (7), 13.3% (4), 10.0% (3), 10.0% (3), 6.6% (2), and 6.6% (2) respectively. The present study showed many antibiotics were not active against gram positive bacteria isolated e.g. the resistance frequenciy to rifampcin, vancomycin and clindamycin was 48%, 44% and 40% respectively. Conclusions: The gram positive organisms were more prevalent than gram negative organisms in patients with bacteriospermia and the isolationfrequencies of two groups were 16 (53.3%) and 14 (46.7%) respectively. The most effective antimicrobial agents were amikacin, ciprofloxacin and levofloxacin and the least effective one was ceftazidime, whereas moxifloxacin, norfloxacin, gentamicin, azithromycin, moxifloxacin, norfloxacin, cefotaxime, and ceftriaxon 展开更多
关键词 Antibiotic RESISTANCE Bacteriospermia BACTERIA Iraq
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Microbial Assay of Otamiri River and Its Sediments in Parts of Owerri 预览
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作者 Victor Inumidun Fagorite Cosmas Ahamefula Ahiarakwem +4 位作者 Sabinus Ikechukwu Ibeneme Ekeoma Sandra Chinemelu Judith Ifeanyi Ukwajiunor Chidimma Maria Abiahu John Olalekan Poopola 《地球科学和环境保护期刊(英文)》 2019年第8期155-166,共12页
The aim of the study was to analyse and identify microbial constituents in the water and sediment samples with comparison of the River to World Health Organisation (WHO, 2011) standard for drinking water and Federal M... The aim of the study was to analyse and identify microbial constituents in the water and sediment samples with comparison of the River to World Health Organisation (WHO, 2011) standard for drinking water and Federal Ministry of Environment (FME, 2006) and their public health implications with respect to water quality. The microbial assay of Otamiri River was investigated using Standard plate count. The result indicates that microbial constituents of Otamiri river obtained at five strategic gauge stations designated SSWS1 (Egbu), SSWS2 (Timber Market), SSWS3 (FUTO), DOWNSTREAM (Mbirichi) and CONTROL POINT with mean Total coliform Count of 3.0 × 102, 3.0 × 103, 4.1 × 103 and 1.0 × 103 cfu/100ml with control point value of 0.5 × 103 respectively. The mean Total Bacteria Count was 3.0 × 104, 2.1 × 103, 1.1 × 103 and 0.8 × 103 cfu/100ml respectively with control point value of 0.2 × 103 while the mean values for Total E. coli Count were 1.1 × 102, 3.0 × 102, 4 × 103 and 2.0 × 103 cfu/100ml with control point value of 0.2 × 103. The biochemical identification of some organisms in water was Escherichia coli, Vibro spp., Klebsiella spp., and Entrobacteria spp. The result of stream sediment samples indicates that the mean Total Bacterial Count was 3.5 × 104, 5.0 × 104, 6.5 × 104 and 2.0 × 104 cfu/g respectively with 1.5 × 102 as control point value and that of Total Coliform Count was 6.5 × 103, 2.0 × 103, 2.5 × 103 and 0.8 × 103 cfu/g respectively with control point value of 0.5 × 102. While for the Total E. coli Count, the values were 2.5 × 103, 1.0 × 103, 2.5 × 103 and 0.5 × 105 cfu/g respective with control as 0.5 × 102. Biochemical identification of some organisms in sediments includes: Escherichia coli, Vibro spp., Klebsiella spp., Entrobacteria spp. and Bacillus spp. The mean total bacterial count, total coli form count and total E. coli, were not in conformity with both World Health Organisation (WHO, 2011) Standard for drinking water and Federal Ministry of Environment (FME) 2006 sta 展开更多
关键词 COLIFORMS E. COLI Bacteria Otamiri RIVER SEDIMENTS and CHLORINATION
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Isolation of Iron Bacteria from Washing Sludge Filters Kolda (Senegal) Water Treatment Station and Study of the Kinetics of Biological Degradation of the Iron (II) 预览
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作者 Mamadou Faye Falilou Mbacké Sambe +3 位作者 Modou Dieng Alpha Ousmane Touré Matar Faye Codou Guèye Mar Diop 《金属学报(美国)》 2019年第3期19-32,共14页
In the present work, the treatment of synthetic waters doped with iron (II) has been studied. The treatment mechanism used in this study is the biological oxidation which consists, in test tubes, of bringing bacteria ... In the present work, the treatment of synthetic waters doped with iron (II) has been studied. The treatment mechanism used in this study is the biological oxidation which consists, in test tubes, of bringing bacteria isolated on Petri dishes into contact with water containing divalent iron (II). These de-ironing bacteria (non-specific bacteria) are used to carry out laboratory biological oxidation experiments on iron (II) under different pH conditions (pH = 3.4 - 3.6, pH = 7.3 - 7.5 and pH = 9.8 - 10) and variable concentration of iron (II). Biological treatment trials included different concentrations of iron during time intervals of a day. Examination of the elimination kinetics of Iron (II) indicates a removal rate of 59.453% for an initial iron concentration in the synthetic solution of 1 mg&middot;L&minus;1 at basic pH (pH = 9.8 - 10). Therefore, the degradation of divalent iron by this method seems to be quite effective, but it should be noted that biological nitrification is impaired by the presence of high iron concentrations above 5 mg&middot;L&minus;1. 展开更多
关键词 BIODEGRADATION Bacteria WASHING MUD IRON KINETICS Efficiency
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