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16S rRNA基因检测在假体周围感染诊断中的应用 预览
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作者 塔拉提百克·买买提居马 王瑞 +4 位作者 焦洋 刘恒 李翔 杨姗 曹永平 《实用骨科杂志》 2019年第2期143-145,共3页
随着人工关节置换的数量增加,关节置换术后并发症也越来越受到人们的重视。无菌性松动(aseptic failure,AF)和假体周围感染(prosthetic joint infection,PJI)是患者面临关节翻修手术的两大常见原因,但二者在临床上却时常较难鉴别。由于... 随着人工关节置换的数量增加,关节置换术后并发症也越来越受到人们的重视。无菌性松动(aseptic failure,AF)和假体周围感染(prosthetic joint infection,PJI)是患者面临关节翻修手术的两大常见原因,但二者在临床上却时常较难鉴别。由于培养技术有限,很多不典型的PJI被误认为是AF。研究发现,PJI消耗的医疗资源和费用是AF的2.8倍[1]。2010年美国骨科医师协会有关PJI的指南指出[2],虽然初次髋和膝关节置换术后假体周围感染的发生率仅为1%~4%,但是一旦发生,对患者来说就是灾难性的。 展开更多
关键词 感染诊断 周围 假体 基因检测 RRNA 16S 人工关节置换 膝关节置换术后
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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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草金鱼腐皮病病原菌的分离及鉴定
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作者 李晓红 陈丽英 +3 位作者 陈梦婷 吴世洲 蒋文贤 陈培富 《黑龙江畜牧兽医》 CAS 北大核心 2019年第8期151-153,173共4页
昆明某郊县一个养殖场的草金鱼患腐皮病,为了有效治疗该病,笔者从患腐皮病草金鱼的肝脏、肌肉溃烂及病灶边缘处采集病料并划线接种于绵羊血琼脂培养基上,培养后分别获得3株病原菌,菌株编号分别为AR0091、AR0027和UMH12,对其进行细菌形... 昆明某郊县一个养殖场的草金鱼患腐皮病,为了有效治疗该病,笔者从患腐皮病草金鱼的肝脏、肌肉溃烂及病灶边缘处采集病料并划线接种于绵羊血琼脂培养基上,培养后分别获得3株病原菌,菌株编号分别为AR0091、AR0027和UMH12,对其进行细菌形态学观察、药敏试验,并采用聚合酶链式反应(PCR)技术扩增16S rRNA基因序列并测序。结果表明:菌株AR0091、AR0027、UMH12均为革兰阴性短杆菌,大部分成对排列。AR0091、AR0027菌株均对阿米卡星、庆大霉素、复方新诺明、卡那霉素、头孢他啶、环丙沙星、多西环素高度敏感;UMH12菌株对阿米卡星、庆大霉素、复方新诺明、头孢他啶、环丙沙星药物高度敏感,而对卡那霉素和多西环素敏感;3株菌株均对氨苄西林耐药。基因测序获得长度为1 463 bp、1 465 bp和1 464 bp的基因序列,经与GenBank做在线BLAST分析发现菌株之间同源性为98.5%,有25个核酸位点的共同差异性,分离菌株为黏质沙雷氏菌。 展开更多
关键词 草金鱼 腐皮病 16S RRNA 黏质沙雷氏菌 药敏试验
一株罕见Ihumii放线菌的分离和鉴定 预览
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作者 张维清 林宇岚 +3 位作者 甘龙杰 陈守涛 张文明 杨滨 《国际检验医学杂志》 CAS 2019年第4期508-510,共3页
放线菌大多存在于健康人口腔、上呼吸道、胃肠道和泌尿生殖道等与外界相通的腔道,是寄居人体的一种正常菌群^[1-2]。当机体免疫力减弱、口腔卫生不良、拔牙或外伤时,可侵入组织导致皮肤、皮下组织,肌肉,骨骼及中枢神经系统化脓性感染^[3... 放线菌大多存在于健康人口腔、上呼吸道、胃肠道和泌尿生殖道等与外界相通的腔道,是寄居人体的一种正常菌群^[1-2]。当机体免疫力减弱、口腔卫生不良、拔牙或外伤时,可侵入组织导致皮肤、皮下组织,肌肉,骨骼及中枢神经系统化脓性感染^[3]。根据感染的途径和涉及的器官不同,临床上分为面颈部、胸部、腹部和中枢神经系统感染。其主要特征为慢性化脓性肉芽肿病变,以向周围组织扩展形成瘘管并排出带有硫磺样颗粒的脓液为特征。绝大多数放线菌易引起内源性感染,大量应用免疫抑制剂是一个重要的诱发因素。2015年,法国科学家从一个50岁的HIV感染者粪便中首次分离出一株新的放线菌,并命名为Ihumii放线菌^[4]。福建医科大学附属第一医院于2016年收治一例由Ihumii放线菌引起的膝关节化脓性感染,现报道如下。 展开更多
关键词 Ihumii放线菌 MALDI-TOF-MS 16S RRNA
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肉鸡金黄色葡萄球菌的生物学特性研究 预览
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作者 崔明仙 白悦 +5 位作者 付岳林 许利军 陈立功 王学静 刘娜 刘聚祥 《今日畜牧兽医》 2019年第3期8-9,7共3页
为调查肉鸡跗关节肿胀的病因,从河北省发病肉鸡采集跗关节分泌物中分离、纯化10株细菌。培养特性、染色特性及生化特性的鉴定结果表明,10株细菌均为金黄色葡萄球菌。16S rRNA序列分析结果进一步证实3株代表菌属于金黄色葡萄球菌。药敏... 为调查肉鸡跗关节肿胀的病因,从河北省发病肉鸡采集跗关节分泌物中分离、纯化10株细菌。培养特性、染色特性及生化特性的鉴定结果表明,10株细菌均为金黄色葡萄球菌。16S rRNA序列分析结果进一步证实3株代表菌属于金黄色葡萄球菌。药敏试验结果显示10株分离菌耐药性较强,具有多重耐药性。动物试验结果表明,分离菌对小鼠具有较强的致病性。 展开更多
关键词 跗关节 金黄色葡萄球菌 16S RRNA 序列分析 耐药性 致病性
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A new species of Crocodile Newt,genus Tylototriton(Amphibia,Caudata,Salamandridae)from the mountains of Kachin State,northern Myanmar
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作者 Than Zaw Paw Lay +2 位作者 Parinya Pawangkhanant Vladislav A.Gorin Nikolay A.Poyarkov,Jr 《动物学研究》 CAS CSCD 2019年第3期151-174,共24页
We describe a new species of the genus Tylototriton from Ingyin Taung Mt.,Mohnyin Township,Kachin State,Myanmar,based on morphological and molecular evidence.The new species is assigned to the subgenus Tylototriton s.... We describe a new species of the genus Tylototriton from Ingyin Taung Mt.,Mohnyin Township,Kachin State,Myanmar,based on morphological and molecular evidence.The new species is assigned to the subgenus Tylototriton s.str.and is clearly distinct from all known congeners by the following characters:medium body size;thin,long tail,lacking lateral grooves;rough skin;truncate snout;wide,protruding supratemporal bony ridges on head,beginning at anterior corner of orbit;weak,almost indistinct sagittal ridge;long,thin limbs,broadly overlapping when adpressed along body;distinct,wide,non-segmented vertebral ridge;13 or 14 rib nodules;brown to darkbrown background coloration with dull orange-brown to yellowish-brown markings on labial regions,parotoids,rib nodules,whole limbs,vent,and ventral tail ridge.We also briefly discuss biogeography and species diversity of the genus Tylototriton in Myanmar. 展开更多
关键词 Tylototriton kachinorum sp.nov. mtDNA GENEALOGY ND2 16S rRNA Shan Biogeography ENDEMISM Taxonomy
犬咬伤伤口分离出咬伤巴斯德菌1例报道及文献复习 预览
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作者 申春梅 沈芳 +1 位作者 贺乐奇 刘红 《检验医学》 CAS 2019年第1期92-94,共3页
巴斯德菌属包括12个种3个亚种,主要为侵肺巴斯德菌、多杀巴斯德菌、咬伤巴斯德菌、产气巴斯德菌和犬巴斯德菌等。人类感染巴斯德菌属细菌多是由猫或狗抓咬引起的局部感染,全身感染不多见,一般见于有基础性疾病的患者^[1]。在由巴斯德菌... 巴斯德菌属包括12个种3个亚种,主要为侵肺巴斯德菌、多杀巴斯德菌、咬伤巴斯德菌、产气巴斯德菌和犬巴斯德菌等。人类感染巴斯德菌属细菌多是由猫或狗抓咬引起的局部感染,全身感染不多见,一般见于有基础性疾病的患者^[1]。在由巴斯德菌属细菌引起的感染中,侵肺巴斯德菌和多杀巴斯德菌较常见^[2-3],而咬伤巴斯德菌的分离率仅为4%~7%^[4-5],并常与其他细菌一起被分离^[6]。咬伤巴斯德菌不容易鉴定,可能是导致其分离率低的一个原因^[7-8]。目前国内关于咬伤巴斯德菌的文献不多,本研究报道1例由咬伤巴斯德菌引起的局部感染病例,以提高临床和微生物实验室对此类感染的认识。 展开更多
关键词 咬伤巴斯德菌 咬伤 基质辅助激光解析电离飞行时间质谱 16S RRNA
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犬粪肠球菌的分离鉴定及耐药性分析
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作者 王俊书 徐进强 +2 位作者 金红岩 封家旺 侯绍华 《黑龙江畜牧兽医》 CAS 北大核心 2019年第2期158-161,182共5页
为了鉴定从拉萨市病犬的粪便中分离出的一株细菌的种属及耐药性,试验采用了革兰氏染色、生化鉴定、16S rRNA PCR扩增和序列比对及药敏试验的方法对该菌株进行了研究。结果表明:该分离菌株为革兰氏阳性菌,经16S rRNA PCR鉴定为粪肠球菌,... 为了鉴定从拉萨市病犬的粪便中分离出的一株细菌的种属及耐药性,试验采用了革兰氏染色、生化鉴定、16S rRNA PCR扩增和序列比对及药敏试验的方法对该菌株进行了研究。结果表明:该分离菌株为革兰氏阳性菌,经16S rRNA PCR鉴定为粪肠球菌,仅对多黏菌素B和利奈唑胺表现高度敏感,对其他28种抗生素均表现耐药。说明从犬中分离出的粪肠球菌对多种抗生素都具有极高的耐药性。 展开更多
关键词 粪肠球菌 分离鉴定 16S RRNA 药敏试验 耐药性
Molecular characterization and toxin quantification of Microcystis panniformis: A microcystin producer in Lake Taihu, China
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作者 Yilu Gu Xiaofeng Gao +2 位作者 Yongguang Jiang Xin Peng Renhui Li 《环境科学学报:英文版》 SCIE EI CAS CSCD 2019年第2期359-367,共9页
Microcystis panniformis is a bloom forming species with flat panniform-like colonies. This species was recently found in Lake Taihu, China. To specifically characterize M. panniformis based on isolated strains, morpho... Microcystis panniformis is a bloom forming species with flat panniform-like colonies. This species was recently found in Lake Taihu, China. To specifically characterize M. panniformis based on isolated strains, morphological examination on colonial transition and genetic examination are needed. Three M. panniformis strains isolated from a water bloom sample in Lake Taihu were characterized by molecular analysis and toxin quantification. Phylogenetic analysis based on both 16S rRNA gene and internal transcribed spacer (ITS) between 16S and 23S rRNA genes were performed and compared to facilitate easy identification of the species. Relatively high similarities (98%–99%) were shown in 16S rDNA sequences between the strains of M. panniformis and those of other Microcystis species, whereas the similarities for ITS sequences were 88%–95%. In the phylogenetic tree based on the 16S rDNA sequences, the M. panniformis and M. aeruginosa strains were intermixed together with no clear division, whereas all of the M. panniformis strains were clustered together in a single clade based on the ITS sequences based phylogenyetic tree. The mcyE gene was detected in all three strains, and microcystin was determined by high-performance liquid chromatography. The molecular detection and toxin production of M. panniformis strains are of great significance for the environmental risk assessment of Microcystis blooms. 展开更多
关键词 MICROCYSTIS panniformis BLOOMS ITS of 16S-23S rRNA mcyE MICROCYSTIN Taihu
Procyanidin B2 protects against diet-induced obesity and nonalcoholic fatty liver disease via the modulation of the gut microbiota in rabbits 预览
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作者 Ya-Wei Xing Guang-Tao Lei +2 位作者 Qing-Hua Wu Yu Jiang Man-Xiang Huang 《世界胃肠病学杂志:英文版》 SCIE CAS 2019年第8期955-966,共12页
BACKGROUND Procyanidins have beneficial effects on metabolic syndrome and antimicrobial activity,but the mechanisms underlying these effects are unclear.AIM To investigate the effects of procyanidin B2(PB2)on non-alco... BACKGROUND Procyanidins have beneficial effects on metabolic syndrome and antimicrobial activity,but the mechanisms underlying these effects are unclear.AIM To investigate the effects of procyanidin B2(PB2)on non-alcoholic fatty liver disease and to explore the possible mechanism.METHODS Thirty male New Zealand white rabbits were randomized into three groups.All of them were fed either a high-fat-cholesterol diet(HCD)or chow diet.HCD-fed rabbits were treated with vehicle or PB2 daily for 12 wk.Body weight and food intake were evaluated once a week.Serum biomarkers,such as total cholesterols,triglycerides,and aspartate transaminase,were detected.All rabbits were sacrificed and histological parameters of liver were assessed by hematoxylin and eosin-stained sections.Moreover,several lipogenic genes and gut microbiota(by 16S rRNA sequencing)were investigated to explore the possible mechanism.RESULTS The HCD group had higher body weight,liver index,serum lipid profile,insulin resistance,serum glucose,and hepatic steatosis compared to the CHOW group.PB2 treatment prevented HCD-induced increases in body weight and hypertriglyceridemia in association with triglyceride accumulation in the liver.PB2 also ameliorated low-grade inflammation,which was reflected by serum lipopolysaccharides and improved insulin resistance.In rabbit liver,PB2 prevented the upregulation of steroid response element binding protein 1c and fatty acid synthase and the downregulation of carnitine palmitoyltransferase,compared to the HCD group.Moreover,HCD led to a decrease of Bacteroidetes in gut microbiota.PB2 significantly improved the proportions of Bacteroidetes at the phylum level and Akkermansia at the genus level.CONCLUSION Our results indicate the possible mechanism of PB2 to improve HCD-induced features of metabolic syndrome and provide a new dietary supplement. 展开更多
关键词 PROCYANIDIN Rabbit Non-alcoholic fatty liver disease GUT MICROBIOTA 16S rRNA
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Bacterial Diversity in Alpine Lakes: A Review from the Third Pole Region
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作者 Namita Paudel Adhikari Subash Adhikari +2 位作者 Xiaobo Liu Liang Shen Zhengquan Gu 《地球科学学刊:英文版》 SCIE CAS CSCD 2019年第2期387-396,共10页
Microorganisms are unique among all of the living organisms because of their high population size, advanced genetic diversity, short generation time, and quick response to the small change in environmental conditions.... Microorganisms are unique among all of the living organisms because of their high population size, advanced genetic diversity, short generation time, and quick response to the small change in environmental conditions. Remote alpine lakes of the Third Pole region provide the unique habitat for microorganisms acting as a natural laboratory and offering the information about the ecological roles of microorganisms. Many researchers focused on microbial communities as well as the impact of physicochemical, biological and hydrological parameters in lakes of this region since decades but the comprehensive review focusing on bacterial diversity and the role of environmental parameters still lacks. Here we reviewed bacterial diversity in lakes of the Third Pole region by analyzing 16 S rRNA clone libraries accessed from previous research findings. A total of 5 388 bacterial 16 S rRNA gene sequences were analyzed and classified into different phylogenetic groups. The average relative abundance of dominant taxa includes Betaproteobacteria(19%), Bacteroidetes(18%), Gammaproteobacteria(16%), Actinobacteria(15%), Alphaproteobacteria(14%), Cyanobacteria(7%), and Firmicutes(5%). Several adaptational strategies were adopted by these dominant bacterial groups in order to accommodate in the respective habitat. Nevertheless, lake water properties like temperature, pH, salinity, incident UV radiation, turbidity, and nutrients also played role in bacterial diversity. 展开更多
关键词 BACTERIAL DIVERSITY ALPINE LAKES 16S rRNA THIRD Pole region
Ciliates in the Marsh Wetlands of Chongming Island:Taxonomy of Five Species and a Species List 预览
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作者 MA Zuhang DONG Tianyao +3 位作者 LIAO Wanying FAN Xinpeng XU Yuan GU Fukang 《中国海洋大学学报:英文版》 SCIE CAS CSCD 2019年第2期441-454,共14页
To clarify the confusion surrounding species identification and state intraspecific variations,this research studied the morphological taxonomy of five species,Kentrophyllum cf.setigerum Petz et al.,1995;Zosterodasys ... To clarify the confusion surrounding species identification and state intraspecific variations,this research studied the morphological taxonomy of five species,Kentrophyllum cf.setigerum Petz et al.,1995;Zosterodasys shumerica Aliev,1990;Frontonia tchibisovae Burkovsky,1970;Neourostylopsis orientalis Chen et al.,2013;and Apoholosticha cf.sinica Fan et al.,2014,which were collected from Chongming Island’s marsh wetlands.Kentrophyllum cf.setigerum possesses less somatic kineties than K.setigerum(19–26 right and 18–25 left kineties vs 35–40 right and 30 left kineties).Whether Z.shumerica is identical to Z.transversa Foissner et al.,1994,which was presented in a previous report,was negated.The improved diagnosis for the species is provided.Frontonia tchibisovae was confirmed to have three or four micronuclei,and the number of kinetosome rows in its peniculus 3 varied between China and Russia populations.The new population of N.orientalis bears cortical granules,which differs from the original population that has an arrangement of rows across the dorsal bristles.For A.cf.sinica,there are colorless cortical granules on the ventral side of the new population,whereas in the previously reported populations bright orange,spherical granules were clustered around dorsal cilia.Additionally,we sequenced the small-subunit(SSU)rRNA genes of K.cf.setigerum,N.orientalis,and A.cf.Sinica,and compared the new and reported populations.For the first time,we also provide a species list,including 33 ciliates collected from the wetlands based on living observation and silver staining. 展开更多
关键词 morphology new records PROTOZOA SSU rRNA gene
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一株兔源多杀性巴氏杆菌的分离鉴定及荚膜血清分型
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作者 王锦祥 桑雷 +3 位作者 孙世坤 陈冬金 陈岩峰 谢喜平 《中国养兔》 2019年第1期4-6,13共4页
为确定福建某兔场呼吸道疾病病原,本试验从呼吸道病死兔的肺脏中分离到一株革兰氏阴性菌FZYH001。动物回归试验能复制出症状和病变特征与临床病例相同的病兔,且从人工感染兔的肺脏中能回收到攻毒菌FZYH001,表明分离菌FZYH001为该兔场呼... 为确定福建某兔场呼吸道疾病病原,本试验从呼吸道病死兔的肺脏中分离到一株革兰氏阴性菌FZYH001。动物回归试验能复制出症状和病变特征与临床病例相同的病兔,且从人工感染兔的肺脏中能回收到攻毒菌FZYH001,表明分离菌FZYH001为该兔场呼吸道疾病的病原。根据分离菌的菌落形态、革兰氏染色特征、16S rRNA基因序列和荚膜血清型鉴定结果,确定为荚膜血清型为A型的多杀性巴氏杆菌。药敏试验结果表明,分离菌FZYH001仅对氟苯尼考、恩诺沙星和左氧氟沙星3种药物敏感,对氨苄西林、庆大霉素和四环素等9种药物耐药。 展开更多
关键词 多杀性巴氏杆菌 16S RRNA 荚膜血清型
牦牛漫游球菌的分离与生物学特性鉴定
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作者 温峰琴 项海涛 +3 位作者 郝宝成 邢小勇 包世俊 胡永浩 《中国兽医学报》 CAS CSCD 北大核心 2019年第3期421-425,共5页
为探究1只牦牛屠宰后肝脏有干酪样结节形成的原因,对肝脏进行细菌的分离培养,对分离到的1株细菌的16S rRNA和16S~23S rRNA基因序列用通用引物扩增和并用NCBI blast和MEGA 7进行序列分析,并用Vitek 2全自动微生物鉴定仪进行生化表型的鉴... 为探究1只牦牛屠宰后肝脏有干酪样结节形成的原因,对肝脏进行细菌的分离培养,对分离到的1株细菌的16S rRNA和16S~23S rRNA基因序列用通用引物扩增和并用NCBI blast和MEGA 7进行序列分析,并用Vitek 2全自动微生物鉴定仪进行生化表型的鉴定,用K-B法进行药敏试验,结果显示:该菌的16S rRNA为1 524 bp,NCBI GenBank登录号为MG753544.1,与水獭漫游球菌的同源性较高,16S~23S rRNA有大小不同的2个片段,分别为522,425 bp,NCBI GenBank登录号分别为MG758122.1和MG758123.1。Vitek 2全自动微生物鉴定仪鉴定为迟缓葡萄球菌。该菌对妥布霉素、头孢哌酮、米诺环素等多种药物高度敏感,对苯唑西林、头孢西丁有抗性。结果表明,分离出的细菌为漫游球菌,该菌是否具有致病性还有待进一步试验验证。 展开更多
关键词 漫游球菌 16SrRNA 16S~23S RRNA 生化试验 药敏试验
内蒙古锡林郭勒盟地区优势蜱种及其基因多样性分析
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作者 黄芳 黄天鹏 +4 位作者 贺海燕 吴咪 朝木丽格 王云冲 格日勒图 《中国兽医学报》 CAS CSCD 北大核心 2019年第3期426-431,460共7页
为了解内蒙古锡林郭勒盟地区的优势蜱种及其存在的基因多态性,应用传统形态学和分子生物学相结合的方法,对该地区14个主要牧区采样点进行蜱虫种型的鉴定和基因多态性分析。通过传统形态学鉴定方法,对蜱虫样品进行显微镜观察以初步确定... 为了解内蒙古锡林郭勒盟地区的优势蜱种及其存在的基因多态性,应用传统形态学和分子生物学相结合的方法,对该地区14个主要牧区采样点进行蜱虫种型的鉴定和基因多态性分析。通过传统形态学鉴定方法,对蜱虫样品进行显微镜观察以初步确定蜱属。采用聚合酶链式反应(PCR)对蜱虫的16S rRNA基因序列进行扩增,测序后对蜱种进行分子鉴定和基因序列同源性分析,确定蜱种多样性。应用Mega 6.06软件构建系统进化树,与GenBank数据库中已知蜱虫的16S rRNA进行聚类分析,以确定蜱进化的规律。结果显示14个不同地区的蜱虫均属于草原革蜱,为锡林郭勒盟地区的优势蜱种之一,但不同地区的蜱虫之间存在明显的基因多态性。 展开更多
关键词 16S RRNA 草原革蜱 种型鉴定 基因多样性
Diversity of the endophytic filamentous fungal leaf community at different development stages of eucalyptus 预览
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作者 Paulo Sergio Balbino Miguel Fabio Balbino Miguel +5 位作者 Bruno Coutinho Moreira Marcelo Nagem Valerio de Oliveira Julio Cesar Delvaux Fernanda de Souza Freitas Arnaldo Chaer Borges Maurcio Dutra Costa 《林业研究:英文版》 CAS CSCD 2019年第3期1093-1103,共11页
Fungal endophytic species inhabiting the leaves of eucalypts are capable of utilising leaf sugars and can influence both plant growth and health. Endophytic fungal symbionts can use simple soluble sugars in leaves as ... Fungal endophytic species inhabiting the leaves of eucalypts are capable of utilising leaf sugars and can influence both plant growth and health. Endophytic fungal symbionts can use simple soluble sugars in leaves as their main carbon source. This study set out to determine the diversity and distribution of the endophytic filamentous fungal leaf community in the hybrid Eucalyptus urograndis due to its economic importance. The fungal leaf community was characterised using denaturing gradient electrophoresis (DGGE) and correlated with levels of leaf nutrients and sugars throughout plant development. Sequencing of DGGE bands revealed the presence of Basidiomycota and Ascomycota phyla. Fourteen species and three genera of filamentous fungi were identified, and the population structure was affected by the plant developmental stage. Levels of K, Cu, N and Mn influenced communities from the clonal garden, whereas leaves in the field had higher glucose, fructose and sucrose. Many fungi were found to be specific to a certain development stages: Diplomitoporus crustulinus, Podosphaera tridactyla and Aspergillus restrictus to the clonal garden stage;Chaetomella acutiseta and Ascotricha chartarum to the shading stage;Erratomyces patelii and Saxomyces sp. to the shading output stage;Lepidostroma sp. and Saxomyces sp. to the dispatch stage;and Mycosphaerella populicola to the field stage. Teratosphaeria toledana and Teratosphaeria acidotherma were found at more than one developmental stage. Cladosporium sp. and Rhodosporidium fluviale colonized and persisted in plants at the dispatch and field stages. This is the first report of P. tridactyla, A. restrictus, E. patelii, Saxomyces and Lepidostroma sp. as endophytes in eucalipt. 展开更多
关键词 DIVERSITY 18S rRNA Denaturing gradient ELECTROPHORESIS (DGGE) SEQUENCING
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Intestinal toxicity of deoxynivalenol is limited by supplementation with Lactobacillus plantarum JM113 and consequentially altered gut microbiota in broiler chickens 预览
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作者 Shengru Wu Yanli Liu +5 位作者 Yongle Duan Fangyuan Wang Fangshen Guo Fang Yan Xiaojun Yang Xin Yang 《畜牧与生物技术杂志:英文版》 SCIE CAS CSCD 2019年第1期218-230,共13页
Background: Limited research has focused on the effect of Lactobacillus on the intestinal toxicity of deoxynivalenol(DON).The present study was conducted to investigate the role of Lactobacillus plantarum(L.plantarum)... Background: Limited research has focused on the effect of Lactobacillus on the intestinal toxicity of deoxynivalenol(DON).The present study was conducted to investigate the role of Lactobacillus plantarum(L.plantarum) JM113 in protecting against the intestinal toxicity caused by DON.Methods: A total of 144 one-day-old healthy Arbor Acres broilers were randomly distributed into 3 treatments,including the CON(basal diet),the DON(extra 10 mg/kg deoxynivalenol),and the DL(extra 1 × 109 CFU/kg L.plantarum JM113 based on DON group) treatments.The growth performance,organ indexes,intestinal morphology,pancreatic digestive enzymes,intestinal secreted immunoglobulin A(sIgA),jejunal transcriptome,and intestinal microbiota were evaluated.Results: Compared with the CON and DL groups,the DON supplementation altered intestinal morphology,especially in duodenum and jejunum,where villi were shorter and crypts were deeper(P < 0.05).Meanwhile,the significantly decreased mRNA expression of jejunal claudin-1 and occludin(P < 0.05),ileal rBAT and jejunal GLUT1 of 21-day-old broilers(P < 0.05),as well as duodenal PepT1 and ileal rBAT of 42-day-old broilers were identified in the DON group.Moreover,supplementation with L.plantarum JM113 could increase duodenal expression of IL-10 and IL-12 of 21-dayold broilers,ileal s IgA of 42-day-old broilers,and the bursa of Fabricius index of 21-day-old broilers.Further jejunal transcriptome proved that the genes related to the intestinal absorption and metabolism were significantly reduced in the DON group but a significant increase when supplemented with extra L.plantarum JM113.Furthermore,the bacteria related to nutrient utilization,including the Proteobacteria,Escherichia,Cc-115(P < 0.05),Lactobacillus and Prevotella(P < 0.1) were all decreased in the DON group.By contrast,supplementation with L.plantarum JM113 increased the relative abundance of beneficial bacterium,including the Bacteroidetes,Roseburia,Anaerofustis,Anaerostipe,and Ruminococcus bromi(P < 0.05).Specifically,the increased abun 展开更多
关键词 BROILER CHICKENS DEOXYNIVALENOL Gut microbiota Lactobacillus PLANTARUM JM113 mRNA SEQUENCING 16S rRNA gene SEQUENCING
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一株致水貂流产的大肠杆菌的分离鉴定及耐药性检测
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作者 肖丽荣 周琦 +5 位作者 李巧玲 贾青辉 张艳英 高桂生 张召兴 史秋梅 《黑龙江畜牧兽医》 CAS 北大核心 2019年第6期156-158,共3页
为检测唐山某水貂养殖场引起母貂流产的病原菌及其耐药情况,试验采用病原检测、细菌分离与形态观察、生化试验、16S rRNA PCR检测、致病性试验等方法对水貂致病原进行鉴定,并采用药敏试验测定其耐药情况。结果表明:水貂阿留申病毒、犬... 为检测唐山某水貂养殖场引起母貂流产的病原菌及其耐药情况,试验采用病原检测、细菌分离与形态观察、生化试验、16S rRNA PCR检测、致病性试验等方法对水貂致病原进行鉴定,并采用药敏试验测定其耐药情况。结果表明:水貂阿留申病毒、犬瘟热病毒、细小病毒、加德纳杆菌和布鲁氏杆菌等病原检测为阴性;从无菌采集的阴道分泌物及胎儿等病料组织中分离到1株病原菌,将其命名为HB-E2株,该株病原菌为两端钝圆、短小杆状的革兰氏阴性菌,通过PCR检测鉴定为大肠杆菌;HB-E2株大肠杆菌对小白鼠具有很强的致病性,对头孢曲松、头孢克肟、环丙沙星等5种药物高度敏感,对氟苯尼考、头孢拉定、阿米卡星等5种药物中度敏感,对氨苄西林、阿莫西林、新霉素等6种药物耐药。 展开更多
关键词 水貂 大肠杆菌 分离鉴定 16S RRNA PCR 药敏试验
Metastasis-related methyltransferase 1(Merml)represses the methyltransferase activity of Dnmt3a and facilitates RNA polymerase I transcriptional elongation
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作者 Guoliang Lyu Le Zong +8 位作者 Chao Zhang Xiaoke Huang Wenbing Xie Junnan Fang Yiting Guan Lijun Zhang Ting Ni Jun Gu Wei Tao 《分子细胞生物学报:英文版》 SCIE CAS CSCD 2019年第1期78-90,共13页
Stimulatory regulators for DNA methyltransferase activity,such as Dnmt3L and some Dnmt3b isoforms,affect DNA methylation patterns,thereby maintaining gene body methylation and maternal methylation imprinting,as well a... Stimulatory regulators for DNA methyltransferase activity,such as Dnmt3L and some Dnmt3b isoforms,affect DNA methylation patterns,thereby maintaining gene body methylation and maternal methylation imprinting,as well as the methylation landscape of pluripotent cells.Here we show that metastasis-related methyltransferase 1(Merm1),a protein deleted in individuals with Williams-Beuren syndrome,acts as a repressive regulator of Dnmt3a.Merm1 interacts with Dnmt3a and represses its methyltransferase activity with the requirement of the binding motif for S-adenosyl-L-methionine.Functional analysis of gene regulation revealed that Merm1 is capable of maintaining hypomethylated rRNA gene bodies and co-localizes with RNA polymerase I in the nucleolus.Dnmt3a recruits Merml,and in return,Merml ensures the binding of Dnmt3a to hypomethylated gene bodies.Such interplay between Dnmt3a and Merml facilitates transcriptional elongation by RNA polymerase I.Our findings reveal a repressive factor for Dnmt3a and uncover a molecular mechanism underlying transcriptional elongation of rRNA genes. 展开更多
关键词 Merm1 gene body METHYLATION Dnmt3a TRANSCRIPTIONAL ELONGATION rRNA genes
基于3种线粒体基因的珠母贝属系统进化关系 预览
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作者 肖宝华 廖宝林 +3 位作者 刘楚吾 杨小东 谢子强 张武财 《水产学报》 CSCD 北大核心 2018年第3期314-321,共8页
为了研究珠母贝属的分类地位和系统演化情况,通过聚合酶链式反应技术(PCR)扩增并直接测序出雷州半岛珠母贝属中的马氏珠母贝、大珠母贝、珠母贝、斑珠母贝和黑珠母贝的3种线粒体基因(12S r RNA、16S r RNA和COⅠ)部分序列,分析其碱... 为了研究珠母贝属的分类地位和系统演化情况,通过聚合酶链式反应技术(PCR)扩增并直接测序出雷州半岛珠母贝属中的马氏珠母贝、大珠母贝、珠母贝、斑珠母贝和黑珠母贝的3种线粒体基因(12S r RNA、16S r RNA和COⅠ)部分序列,分析其碱基组成和种间遗传距离。同时结合Gen Bank上发表的白珠母贝序列,构建珠母贝属的分子系统树。结果显示,5种珍珠贝的3种基因部分序列碱基AT含量大于GC含量,与其他无脊椎动物线粒体DNA序列基本一致,序列都处于高度饱和的状态。系统分析显示,构建的分子系统树与传统的形态分类基本一致。在黑珠母贝和白珠母贝亲缘关系上,3种线粒体DNA片段在碱基组成、种间遗传距离和系统进化树上都显示黑珠母贝和白珠母贝非常相近,可以认为是同一种中的2个亚种。在斑珠母贝的亲缘关系上,系统分析显示斑珠母贝与黑珠母贝和白珠母贝更为接近。研究表明,大珠母贝和珠母贝在系统进化中较早的分离出来,是一个比较原始的种类。3种分子标记对马氏珠母贝亲缘关系分析上存在一定差异,根据现有的数据尚不足以得出结论,需进一步做分子系统研究并结合形态特征和解剖结构进行分析。 展开更多
关键词 珠母贝属 线粒体基因 12S RRNA 16S RRNA COⅠ 分子系统学
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