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16S与gyrB基因联合建树快速鉴定海水中的一株地衣芽胞杆菌 认领
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作者 傅奇 林俊杰 +2 位作者 甘美裕 卢源钦 肖玉娟 《海洋科学》 CAS 北大核心 2020年第4期90-95,共6页
在保守序列高度相似的细菌鉴定中,单独使用16S rDNA/RNA序列进行比对和构建进化树通常无法准确鉴定到种,需要增加测序基因数并对多基因进行分析。为实现快速鉴定,课题组对16S与gyrB基因联合建树的方法进行了研究,将海洋来源的一株杆菌,... 在保守序列高度相似的细菌鉴定中,单独使用16S rDNA/RNA序列进行比对和构建进化树通常无法准确鉴定到种,需要增加测序基因数并对多基因进行分析。为实现快速鉴定,课题组对16S与gyrB基因联合建树的方法进行了研究,将海洋来源的一株杆菌,分别用通用引物扩增16S和gyrB基因并测序,在GeneBank进行序列比对后,选择各菌种保藏中心16S和gyrB基因均相似的菌株,取16S和gyrB基因序列,采用Paup*4.0构建进化树。使用16S与gyrB拼接序列构建的进化树中属于同一种的菌株均很好的聚合在一枝,种间分枝自展值均高于98,分类结构准确,筛选得到的杆菌与地衣芽胞杆菌(Bacilluslicheniformis)聚合在一枝,自展值为100,鉴定为地衣芽胞杆菌。经生理生化试验验证,该菌株与地衣芽胞杆菌特征完全一致,使用16S和gyrB基因联合建树得到的鉴定结果准确且快速简便。 展开更多
关键词 16S GYRB 进化树 地衣芽胞杆菌(Bacillus licheniformis)
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16S rRNA序列测定结肠腺瘤性息肉与肠道菌群的相关性分析 认领
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作者 陈辞言 段勇 +2 位作者 卯建 牛敏 杜艳 《中华检验医学杂志》 CAS CSCD 北大核心 2020年第2期175-181,共7页
目的探讨作为结肠癌癌前病变的结肠腺瘤性息肉(CAP)中肠道菌群的改变特征。方法随机收集2017年11月至2018年4月在昆明医科大学第一附属医院进行结肠镜检查的结肠腺瘤性息肉患者(CAP组)30例和无腺瘤息肉的健康个体(HC组)30名。通过内镜... 目的探讨作为结肠癌癌前病变的结肠腺瘤性息肉(CAP)中肠道菌群的改变特征。方法随机收集2017年11月至2018年4月在昆明医科大学第一附属医院进行结肠镜检查的结肠腺瘤性息肉患者(CAP组)30例和无腺瘤息肉的健康个体(HC组)30名。通过内镜下电凝电切治疗,收集CAP患者的腺瘤组织和健康志愿者(HC)的肠黏膜组织,提取基因组DNA,对细菌16S rRNA基因V3~V4区进行扩增,通过Illumina MiSeq平台进行序列测定,实验结果使用秩和检验(Wilcoxon检验)进行比较法分析。结果CAP患者的腺瘤组织中肠道菌群α多样性高于健康肠黏膜组织(Chao指数、Ace指数P<0.01)。门水平分析中,CAP组中拟杆菌门(FC=0.38)的丰度显著降低(P<0.01);属水平分析中,拟杆菌属(FC=0.32)、埃希菌属(FC=0.57)、瘤胃球菌属(FC=0.42)、Blautia(FC=0.27)、Dorea(FC=0.57)在CAP组中丰度降低(P<0.05);假单胞菌属(FC=2.43)、乳球菌(FC=2.84)、土芽孢杆菌属(FC=2.07)和不动杆菌属(FC=2.36)丰度升高(P<0.05)。结论与HC肠黏膜组织相比,CAP患者腺瘤组织中菌群的丰度和多样性存在显著的差异,表明腺瘤性息肉患者黏膜中菌群存在失衡现象。这种肠道微环境的失衡,对研究结肠腺瘤性息肉的发生和发展具有重要意义。 展开更多
关键词 结肠肿瘤 腺瘤性息肉 胃肠道微生物组 RNA 核糖体 16S 高通量核苷酸序列分析
Archaea Diversity of Five Hot Springs in Lushan from Henan 认领
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作者 Ke ZHANG Li LIU +8 位作者 Xuyang ZHANG Shufang ZHANG Xinhua ZHENG Yu WANG Junfeng ZHANG Bingjie LI Yunxia ZHOU Fuan WANG Xichao XIA 《气象与环境研究:英文版》 CAS 2020年第1期48-52,共5页
There are five hot springs named separately SHANGT,ZHONGT,WENT,XIAT and SHENT in Lushan County,Pingdingshan City,Henan Province.The archaeal diversity of the five hot springs was investigated and analyzed.16 S rD NA v... There are five hot springs named separately SHANGT,ZHONGT,WENT,XIAT and SHENT in Lushan County,Pingdingshan City,Henan Province.The archaeal diversity of the five hot springs was investigated and analyzed.16 S rD NA v4-5 genes of archaea were sequenced by Illumina Hisiq2500 PE250 technology.The numbers of sample sequences and OTUs were sorted by using Uparse,Mothur,SILVA,MUSCLE and Qiime software.Finally,the archaeal abundance and diversity in the five hot springs were analyzed.87993,67326,44400,48611 and 48495 effective reads have been obtained from SHANGT,ZHONGT,WENT,XIAT and SHENT respectively,and 520,280,678,451 and 437 OTUs have been acquired.The analysis of archaeal classification showed that the archaea from the five hot springs could be classified into 11 phyla,in which Thaumarchaeota accounted for 95.25%and was the dominant archaea.In the genera level,the dominant archaea of the SHANGT,ZHONGT and WENT was Candidatus-Nitrosocaldus,and unidentified-Thaumarchaeota was the dominant archaea in XIAT and SHENT.The results showed that the five hot springs in Lushan are rich in microbial resources.The research provided basic data for further research and utilization of the archaea resources in the five hot springs of Lushan. 展开更多
关键词 Hot spring ARCHAEA 16S RDNA GENES Hisiq2500 PE250
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Inhibition effect of magnetic field on nitrous oxide emission from sequencing batch reactor treating domestic wastewater at low temperature 认领
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作者 Dan Xu Hongmin Ji +3 位作者 Hongqiang Ren Jinju Geng Kan Li Ke Xu 《环境科学学报:英文版》 SCIE EI CAS CSCD 2020年第1期205-212,共8页
This study aims to investigate the effect of a magnetic field on nitrous oxide(N2O)emission from a sequencing batch reactor treating low-strength domestic wastewater at low temperature(10℃).After running for 124 days... This study aims to investigate the effect of a magnetic field on nitrous oxide(N2O)emission from a sequencing batch reactor treating low-strength domestic wastewater at low temperature(10℃).After running for 124 days in parallel,results indicated that the conversion rate of N2O for a magnetic field-sequencing batch reactor(MF-SBR)decreased by34.3%compared to that of a conventional SBR(C-SBR).Meanwhile,the removal efficiencies for total nitrogen(TN)and ammonia nitrogen(NH4-N)of the MF-SBR were 22.4%and 39.5%higher than those of the C-SBR.High-throughput sequencing revealed that the abundances of AOB(Nitrosomonas),NOB(Nitrospira)and denitrifiers(Zoogloea),which could reduce N2O to N2,were promoted significantly in the MF-SBR.Enzyme activities(Nir)and gene abundances(nos Z nir S and nir K)for denitrification in the MF-SBR were also notably higher compared to C-SBR.Our study shows that application of a magnetic field is a useful approach for inhibiting the generation of N2O and promoting the nitrogen removal efficiency by affecting the microbial characteristics of sludge in an SBR treating domestic wastewater at low temperature. 展开更多
关键词 Magnetic field Low temperature N2O emission Biological nitrogen removal HIGH-THROUGHPUT 16S RRNA gene SEQUENCING
Relevance in the Application of IFRS 16 for Financial Statements:Empirical Evidence the Impact of the Financial Method in SMEs 认领
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作者 Secinaro Silvana Brescia Valerio +1 位作者 Iannaci Daniel Chmet Federico 《中国经济评论:英文版》 2020年第1期1-15,共15页
Leasing is confirmed among the preferred forms of financing by SMEs(Small and Medium Enterprises),even if its use grows both among large companies and private individuals.The stipulated in Europe increased in 2017 by ... Leasing is confirmed among the preferred forms of financing by SMEs(Small and Medium Enterprises),even if its use grows both among large companies and private individuals.The stipulated in Europe increased in 2017 by 8.3%over the previous year.From 1 January 2019 the new accounting standard IFRS 16 is in force,which concerns the accounting of leasing contracts.The new methods of accounting for leasing contracts in the financial statements drawn up based on international accounting standards come into force.In fact,as from 1 January 2019,the IAS adopters are required to apply the new IFRS 16 standard,introduced in place of IAS 17,with the aim of standardizing the methods for recognizing leasing contracts in the financial statements.Scientifically,the most important researches concerning leasing have dealt with the topic focusing on accounting harmonization,accounting for leasing,capitalization of leasing and tax.Through the theoretical analysis and the simulation of our case study we want to answer a question:How the change in the accounting of leases is reflected in the financial statements? 展开更多
关键词 ACCOUNTING IFRS 16 leases SMES
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世界名枪印象(3) 从M16步枪谈枪械命运 认领
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作者 晓枪老王 《兵器知识》 2020年第1期26-31,共6页
无论设计师愿不愿意,自诞生以来,枪械就在一定程度上带有政治色彩。对于这个时代而言,技术早已经逐渐停滞,政治越来越决定着枪械的未来。通过剖析M16的"黑历史",了解政治干预技术的毒害,我们可避免重蹈M16发展中的悲剧和覆辙... 无论设计师愿不愿意,自诞生以来,枪械就在一定程度上带有政治色彩。对于这个时代而言,技术早已经逐渐停滞,政治越来越决定着枪械的未来。通过剖析M16的"黑历史",了解政治干预技术的毒害,我们可避免重蹈M16发展中的悲剧和覆辙。"来路不正"的M16在今天,包括M4、AR15在内的整个M16枪械家族早已经成为美国的国家代表之一。 展开更多
关键词 M16 政治干预 枪械
Distribution of Bacterial Communities in Petroleum-Contaminated Soils from the Dagang Oilfi eld, China 认领
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作者 Xueke Feng Zhen Liu +1 位作者 Xiaoqiang Jia Wenyu Lu 《天津大学学报:英文版》 EI CAS 2020年第1期22-32,共11页
Diversity in bacterial communities was investigated along a petroleum hydrocarbon content gradient(0-0.4043 g/g)in surface(5-10 cm)and subsurface(35-40 cm)petroleum-contaminated soil samples from the Dagang Oilfield,C... Diversity in bacterial communities was investigated along a petroleum hydrocarbon content gradient(0-0.4043 g/g)in surface(5-10 cm)and subsurface(35-40 cm)petroleum-contaminated soil samples from the Dagang Oilfield,China.Using 16S rRNA Illumina high-throughput sequencing technology and several statistical methods,the bacterial diversity of the soil was studied.Subsequently,the environmental parameters were measured to analyze its relationship with the community variation.Nonmetric multidimensional scaling and analysis of similarities indicated a significant difference in the structure of the bacterial community between the nonpetroleum-contaminated surface and subsurface soils,but no differences were observed in different depths of petroleum-contaminated soil.Meanwhile,many significant correlations were obtained between diversity in soil bacterial community and physicochemical properties.Total petroleum hydrocarbon,total organic carbon,and total nitrogen were the three important factors that had the greatest impacts on the bacterial community distribution in the long-term petroleum-contaminated soils.Our research has provided references for the bacterial community distribution along a petroleum gradient in both surface and subsurface petroleum-contaminated soils of oilfield areas. 展开更多
关键词 Petroleum-contaminated soil Dagang OILFIELD BACTERIAL community DIVERSITY 16s RRNA ILLUMINA SEQUENCING Environmental factor correlation analysis
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应用16S rRNA基因序列分析鉴定从痰培养中分离的假肺炎链球菌 认领
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作者 赖希希 蔡鹏威 +1 位作者 王军军 屈平华 《实验与检验医学》 CAS 2020年第2期222-224,共3页
目的对含有革兰阳性球菌的痰培养分离出的草绿色链球菌样菌落进行16S rRNA基因序列分析与质谱鉴定,探讨16S rRNA基因序列分析与质谱在临床病原菌鉴定方面的意义。方法将分离的菌株采用奥布托辛(OP)试验、Vitek MS质谱鉴定以及16S rRNA... 目的对含有革兰阳性球菌的痰培养分离出的草绿色链球菌样菌落进行16S rRNA基因序列分析与质谱鉴定,探讨16S rRNA基因序列分析与质谱在临床病原菌鉴定方面的意义。方法将分离的菌株采用奥布托辛(OP)试验、Vitek MS质谱鉴定以及16S rRNA基因测序进行鉴定。结果OP试验结果在5%CO2气体环境中抑菌圈直径为15mm,在大气中培养抑菌圈直径为25mm。Vitek MS质谱鉴定显示为假肺炎链球菌,可信度99.9%。16S rRNA基因测序鉴定结果显示该菌与肺炎链球菌的相似度为99.63%,与假肺炎链球菌的相似度更高为99.75%。结论结合表型鉴定结果,可进一步确定分离株为假肺炎链球菌。 展开更多
关键词 慢性阻塞性肺疾病 假肺炎链球菌 16S RRNA基因序列分析 质谱
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乳源莱山遗址ⅢM16发掘简报 认领
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作者 陈司林 《客家文博》 2020年第1期60-62,共3页
一、发现及发掘过程乳源莱山遗址位于韶关市乳源瑶族自治县桂头镇北侧,地处武江东岸,墓葬主要分布在低矮山岗之上。2018年9月—2019年4月,广东省文物考古研究所为配合韶关机场建设联合乳源博物馆对该遗址进行了发掘。墓葬位于莱山遗址... 一、发现及发掘过程乳源莱山遗址位于韶关市乳源瑶族自治县桂头镇北侧,地处武江东岸,墓葬主要分布在低矮山岗之上。2018年9月—2019年4月,广东省文物考古研究所为配合韶关机场建设联合乳源博物馆对该遗址进行了发掘。墓葬位于莱山遗址区域Ⅲ盐冲岭,编号为2018SRLⅢM16(ⅢM16)。 展开更多
关键词 乳源瑶族自治县 发掘简报 莱山 M16 遗址 韶关市
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Spatial distribution characteristics of bacterial community structure and gene abundance in sediments of the Bohai Sea 认领
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作者 Quanrui Chen Jingfeng Fan +10 位作者 Jie Su Hongxia Ming Zhihao Sun Mengfei Li Xiaohui Zhao Yantao Wang Yingxue Zhang Huizhen Zhang Yuan Jin Xiaowan Ma Bin Wang 《海洋学报:英文版》 SCIE CAS CSCD 2020年第2期69-78,共10页
This study investigated differences in the community structure and environmental responses of the bacterial community in sediments of the Bohai Sea.Illumina high-throughput sequencing technology and real-time PCR were... This study investigated differences in the community structure and environmental responses of the bacterial community in sediments of the Bohai Sea.Illumina high-throughput sequencing technology and real-time PCR were used to assay the bacterial 16S rRNA genes in the surface sediments of 13 sampling stations in the Bohai Sea.The results showed that sediments at the majority of the 13 sampling stations were contaminated by heavy metal mercury.The main phyla of bacteria recorded included Proteobacteria(52.92%),Bacteroidetes(11.76%),Planctomycetes(7.39%),Acidobacteria(6.53%)and Chloroflexi(4.97%).The genus with the highest relative abundance was Desulfobulbus(4.99%),which was the dominant genus at most sampling stations,followed by Lutimonas and Halioglobus.The main factors influencing bacterial community structure were total organic carbon,followed by depth and total phosphorus.The content of lead,cadmium,chromium,copper and zinc had a consistent effect on community structure.Arsenic showed a negative correlation with bacterial community structure in most samples,while the impact of mercury on community structure was not significant.The bacterial community in sediment samples from the Bohai Sea was rich in diversity and displayed an increase in diversity from high to low latitudes.The data indicated that the Bohai Sea had abundant microbial resources and was rich in bacteria with the potential to metabolize many types of pollutants. 展开更多
关键词 Bohai Sea SEDIMENTS bacterial community structure HIGH-THROUGHPUT SEQUENCING 16S rRNA GENE
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中药对肠道菌群结构和功能作用的研究 认领
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作者 田思聪 薛婧 +1 位作者 宋辉 杜权 《中国药学:英文版》 CAS CSCD 2020年第3期161-175,共15页
为了探讨中草药对肠道菌群的调节作用,我们选择王氏保赤丸和三七总皂甙两种具有悠久应用历史的中药开展本研究。研究模型为雄性Wistar大鼠,分为高中低三个剂量组,连续给药28天。给药结束后,收集大鼠的新鲜粪便进行16S rRNA测序,以确定... 为了探讨中草药对肠道菌群的调节作用,我们选择王氏保赤丸和三七总皂甙两种具有悠久应用历史的中药开展本研究。研究模型为雄性Wistar大鼠,分为高中低三个剂量组,连续给药28天。给药结束后,收集大鼠的新鲜粪便进行16S rRNA测序,以确定肠道菌群的组成谱。与对照组相比,发现王氏保赤丸对乳酸杆菌和拟杆菌的丰度产生了平衡的调节作用,这与其对便秘和腹泻独特的双向作用是一致的。研究进一步发现,王氏保赤丸给药提高了短链脂肪酸生产菌Ruminiclostridium_9和Eubacterium_ventriosum的丰度,减少了与炎症相关的Jeotgalicoccus和Bilophila属的丰度,使大鼠肠道菌群的整体组成更加健康。对三七总皂甙给药组的研究发现,三七总皂甙对与帕金森氏病相关的肠杆菌科,与衰老相关的Christensenellaceae菌科、以及与高血压有关的Rikenellaceae、Christensenellaceae、Lachnospiraceae和Bacteroidaceaceae菌属均具有显著的调节作用,这些作用与其主要的临床适应症是相符的,三七总皂甙给药还能提高短链脂肪酸生产菌群的丰度,包括Elusimicrobium、Anaerotruncus、Ruminococcaceae_NK4A214_group和Intestinimonas。对王氏保赤丸和三七总皂甙的研究表明,两种中药不仅对肠道菌群具有各自特征性的调节作用,这些调节作用还与它们独特的临床治疗效果相一致,提示我们肠道菌群极有可能参与了王氏保赤丸和三七总皂甙对疾病的治疗过程。 展开更多
关键词 肠道菌群 中药 16S rRNA测序
两株羊溶血性曼氏杆菌的分离及其生物学特性研究 认领
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作者 聂荷莲 周佳 +4 位作者 高尚 曾紫雄 张信军 成大荣 王彦红 《黑龙江畜牧兽医》 CAS 北大核心 2020年第5期77-80,共4页
为了分离新型曼氏杆菌并研究其生物学特性,试验对从两例山羊病例中分离出的相似细菌进行纯化培养,通过革兰氏染色镜检、生化试验、16S rDNA基因序列测定、多位点序列分型法(MLST)鉴定、血清型鉴定、药敏试验等方法研究其生物学特性。结... 为了分离新型曼氏杆菌并研究其生物学特性,试验对从两例山羊病例中分离出的相似细菌进行纯化培养,通过革兰氏染色镜检、生化试验、16S rDNA基因序列测定、多位点序列分型法(MLST)鉴定、血清型鉴定、药敏试验等方法研究其生物学特性。结果表明:分离得到2株革兰氏阴性菌,2株细菌的生化试验和16S rDNA基因序列分析鉴定符合溶血性曼氏杆菌的特点,将其分别命名为201705YF和201805YS;对2株细菌进行血清型1型、2型和6型的多重PCR鉴定,201705YF为血清型2型,而201805YS的1型、2型和6型血清型检测为阴性;对2株细菌的7个管家基因adk、aroE、deoD、gapDH、gnd、mdh和zwf进行扩增并测序,菌株201705YF对应的7个管家基因的序列号为50,20,15,19,15,17,19,菌株201805YS对应的7个管家基因的序列号为1,2,20,2,1,1,1,这2株细菌的基因型为新基因型,即ST50和ST51;2株细菌对左氧氟沙星、卡那霉素、多黏菌素B、氟苯尼考、诺氟沙星、多西环素、美洛西林、环丙沙星、头孢哌酮等抗生素敏感,但201705YF对丁胺卡那耐药,201805YS对庆大霉素、新霉素、妥布霉素耐药。说明从送检病死山羊中分离出的2株细菌为不同血清型和新ST型的溶血性曼氏杆菌,为溶血性曼氏杆菌进化和流行病学关系研究提供了新的相关研究数据。 展开更多
关键词 溶血性曼氏杆菌 鉴定 16S rDNA基因序列 MLST分型 药敏试验
规模化猪场粪污高效脱硫菌的分离、筛选与鉴定 认领
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作者 刘雪纯 耿晓晴 +4 位作者 丁轲 余祖华 李旺 李元晓 何万领 《中国畜牧杂志》 CAS 北大核心 2020年第3期107-110,共4页
为降解规模化猪场污水中的S^2-,本研究从规模化猪场采集粪便污水样品20份,首先接种于含10 g/L Na2S的基础无机盐培养基中富集培养,然后涂布于分离培养基进行分离与纯化。对纯化的菌株采用对氨基二甲基苯胺分光光度法测定培养上清中S^2-... 为降解规模化猪场污水中的S^2-,本研究从规模化猪场采集粪便污水样品20份,首先接种于含10 g/L Na2S的基础无机盐培养基中富集培养,然后涂布于分离培养基进行分离与纯化。对纯化的菌株采用对氨基二甲基苯胺分光光度法测定培养上清中S^2-含量,筛选菌株的脱硫能力。选择降解率较高的菌株进行生理生化鉴定和16S rDNA分子鉴定,并对扩增的序列进行同源性比较及进化树分析。结果表明:从20个样品中分离了14株菌株,筛选获得2株脱硫率较高的菌株JFF-2和JFF-3,脱硫率可达84.02%和86.12%;经16S rDNA序列分析表明,JFF-2菌与地衣芽孢杆菌的同源性为99.2%,JFF-3菌与粪产碱杆菌的同源性为98.7%,因此分别确定为地衣芽孢杆菌和粪产碱杆菌,与生理生化鉴定的结果一致。本研究获得了2株能够对畜禽粪便污水脱硫的菌株,为畜禽排泄物的进一步无害化处理提供了可能。 展开更多
关键词 硫降解菌 16S RDNA 鉴定 筛选 规模化猪场
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5分钟识别美军M16系列步枪5种型号 认领
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作者 伦敦上空的喷火 《轻兵器》 2020年第5期35-37,共3页
M16与M16A1步枪M16A1是在M16基础上针对越南战争环境做出改良的型号,两者基本设计相同,主要是加固了内部零件的强度,给枪管镀铬,增加了一个辅助推机柄,还有一些外观上的小改动。两者在外观上是非常接近的,最直观的区别就是M16A1的机匣... M16与M16A1步枪M16A1是在M16基础上针对越南战争环境做出改良的型号,两者基本设计相同,主要是加固了内部零件的强度,给枪管镀铬,增加了一个辅助推机柄,还有一些外观上的小改动。两者在外观上是非常接近的,最直观的区别就是M16A1的机匣尾部增加了一个辅助推机柄,而M16的机匣尾部则没有这个部件。 展开更多
关键词 M16 快慢机
政客帕奎奥 认领
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作者 王明琛 《新体育》 2020年第4期78-82,共5页
国民英雄。参议员曼尼·帕奎奥坐在黑色凯迪拉克轿车的第二排,前面的座位靠背上放着一把9毫米口径的手枪。他的助理大卫·西森坐在一旁,几名警察的腿上放着M16自动步枪,手指虚扣着扳机。前面有两辆警用摩托车,在马尼拉的高峰车... 国民英雄。参议员曼尼·帕奎奥坐在黑色凯迪拉克轿车的第二排,前面的座位靠背上放着一把9毫米口径的手枪。他的助理大卫·西森坐在一旁,几名警察的腿上放着M16自动步枪,手指虚扣着扳机。前面有两辆警用摩托车,在马尼拉的高峰车流中鸣笛开道。从车窗往外看,大街小巷到处挤满了摩托车、自行车和人流。 展开更多
关键词 M16 自动步枪 马尼拉 参议员 自行车 摩托车 政客
平塘特大桥16#主塔人工挖孔桩安全质量控制 认领
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作者 向军 《交通世界》 2020年第7期88-89,共2页
以平塘特大桥16#主塔人工挖孔桩项目资料为研究背景,对主塔人工挖孔桩安全质量控制孔要点进行总结研究,包括危险源的辨识、安全施工的过程控制要点、防缺氧及有害气体措施、防坠落事故措施。实践可知,在人工挖孔桩施工时做好工艺控制与... 以平塘特大桥16#主塔人工挖孔桩项目资料为研究背景,对主塔人工挖孔桩安全质量控制孔要点进行总结研究,包括危险源的辨识、安全施工的过程控制要点、防缺氧及有害气体措施、防坠落事故措施。实践可知,在人工挖孔桩施工时做好工艺控制与安全措施设置,能切实提升人工挖孔桩安全质量,对促进项目建设有积极作用。 展开更多
关键词 平塘特大桥 16#主塔 人工挖孔桩 安全质量控制
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Spatial analysis of bacteria in brackish lake sediment 认领
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作者 Jean-Sebastien Beaulne Samir RMishra +5 位作者 Mrutyunjay Suar Ananta Narayan Panda Gurdeep Rastogi Ajit Kumar Pattnaik Vishakha Raina Timothy MVogel 《国际泥沙研究:英文版》 SCIE 2020年第3期227-236,共10页
The spatial distribution of bacterial communities inhabiting sediment is heterogeneous at different spatial scales,but mostly unexplored.Here,it is postulated that the heterogeneity of the bacterial community composit... The spatial distribution of bacterial communities inhabiting sediment is heterogeneous at different spatial scales,but mostly unexplored.Here,it is postulated that the heterogeneity of the bacterial community composition varies at the same scale of the heterogeneity of sediment chemical properties.The large spatial scale(km)diversity in sediment from a brackish water lagoon(Chilika Lake,India)is studied,considering the large scale physical and chemical characteristics of land cover,climate,pH,and salinity.Seventy-two samples(24 stations,3 seasons:winter,rainy,and summer)of sediment from Chilika Lake were analyzed by 16S ribosomal ribonucleic acid(rRNA)gene sequencing,and the relations with land cover and other physico-chemical parameters are discussed.More samples were collected after a severe cyclonic storm(Phailin)passed near the lagoon in 2013,to see the impact of the tropical storm on the spatial and temporal distribution of bacteria in the sediment.The results demonstrate clear spatial relations between physico-chemical parameters(e.g.,salinity),land surfaces(e.g.,drainage area),and the distribution of sediment microbial communities. 展开更多
关键词 SALINITY 16S RRNA Macro-scale SEDIMENT GIS
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Characterizing the composition of intestinal microflora by 16S rRNA gene sequencing 认领
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作者 Wen-Jia Wang You-Lian Zhou +5 位作者 Jie He Zhi-Qiang Feng Long Zhang Xiao-Bo Lai Jun-Xiao Zhou Hong Wang 《世界胃肠病学杂志:英文版》 SCIE CAS 2020年第6期614-626,共13页
BACKGROUND This study determined the composition and diversity of intestinal microflora in patients with colorectal adenoma(CRA),which may provide precedence for investigating the role of intestinal microflora in the ... BACKGROUND This study determined the composition and diversity of intestinal microflora in patients with colorectal adenoma(CRA),which may provide precedence for investigating the role of intestinal microflora in the pathogenesis of colorectal tumors,the composition of intestinal microflora closely related to CRA,and further validating the possibility of intestinal flora as a biomarker of CRA.AIM To study the relationship between intestinal microflora and CRA.METHODS This is a prospective control case study from October 2014 to June 2015 involving healthy volunteers and patients with advanced CRA.High-throughput sequencing and bioinformatics analysis were used to investigate the composition and diversity of intestinal microflora in 36 healthy subjects and 49 patients with advanced CRA.Endpoints measured were operational taxonomic units of intestinal flora,as well as their abundance and diversity(αandβtypes).RESULTS In this study,the age,gender,body mass index,as well as location between controls and patients had no significant differences.The mucosa-associated gut microbiota diversity and bacterial distribution in healthy controls and colorectal adenomas were similar.The operational taxonomic unit,abundance,andαandβdiversity were all reduced in patients with CRA compared to controls.At the phylum level,the composition of intestinal microflora was comparable between patients and controls,but the abundance of Proteobacteria was increased,and Firmicutes and Bacteroides were significantly decreased(P<0.05).The increase in Halomonadaceae and Shewanella algae,and reduction in Coprococcus and Bacteroides ovatus,could serve as biomarkers of CRA.High-throughput sequencing confirms the special characteristics and diversity of intestinal microflora in healthy controls and patients with CRA.CONCLUSION The diversity of intestinal microflora was decreased in patients with CRA.An increase in Halomonadaceae and Shewanella algae are markers of CRA. 展开更多
关键词 16S rDNA INTESTINAL MICROFLORA Advanced COLORECTAL ADENOMA COLORECTAL cancer Biomarkers
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16S rRNA Technology Approach to Explore Mechanism of Qishen Decoction in Improving Nonalcoholic Fatty Liver Fibrosis 认领
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作者 Bing-Yu Wang Ya-Li Zhang +2 位作者 Lei Yang Dan-Dan Li Xing-Xing Yuan 《海南医科大学学报:英文版》 2020年第1期18-23,共6页
Objective: To explore the mechanism of Qishen Decoction in the treatment of nonalcoholicfatty liver fibrosis (NAFLF) by 16S rRNA technology. Methods: NAFLF rat model was established by intraperitoneal injection of car... Objective: To explore the mechanism of Qishen Decoction in the treatment of nonalcoholicfatty liver fibrosis (NAFLF) by 16S rRNA technology. Methods: NAFLF rat model was established by intraperitoneal injection of carbon tetrachloride combined with high fat diet. During the modeling period, each group was given corresponding drug intervention treatment for 8 weeks. The changes of liver histopathology, serum liver function, lipid and liver fibrosis were analyzed and compared after treatment in each group. The contents of cecum end were collected and the intestinal flora was sequenced by Illumina Miseq platform. Results: Compared with the model group, Qishen Decoction could significantly improve the pathological changes of liver tissue in NALFL rats, and reduce the NAS score, oil red staining area, collagen staining area, ALT, AST, TC, TG, HA, LN, PIIINP and C-IV levels, with significant differences (P<0.05). In addition, compared with the control group, the intestinal flora abundance and diversity of the rats in the model group were significantly reduced (P<0.05), Qishen decoction could significantly increase the abundance and diversity of the intestinal flora of NAFLF rats (P<0.05), and upregulated the abundance of Bacteroidales_S24-7_group_unclassified, Bifidobacterium, Lactobacillu s, Turicibacter, Parabacteroides, Phascolarctobacterium, Lachnospiraceae_NK4A136_group, Coriobacteriaceae_UCG-002, Parasutterella, Odoribacter, Anaerostipes, Ruminococcaceae_unclassified, Allobaculum, Romboutsia, Holdemanella, and Haem ophilus, the difference was statistically significant (P<0.05). Conclusion: Qishen Decoction inhibits liver fibrosis in NAFLF rats by restore the diversity of intestinal flora and increase the abundance of probiotics in intestinal tract. 展开更多
关键词 Qishen DECOCTION NONALCOHOLIC fatty liver FIBROSIS Intestinal FLORA 16S rRNA TECHNOLOGY
Analysis of the microbial communities in soils of different ages following volcanic eruptions 认领
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作者 Marcela HERNáNDEZ Marcela CALABI +1 位作者 Ralf CONRAD Marc G.DUMONT 《土壤圈:英文版》 SCIE CAS CSCD 2020年第1期126-134,共9页
Volcanism is a primary process of land formation.It provides a model for understanding soil-forming processes and the role of pioneer bacteria and/or archaea as early colonizers in those new environments.The objective... Volcanism is a primary process of land formation.It provides a model for understanding soil-forming processes and the role of pioneer bacteria and/or archaea as early colonizers in those new environments.The objective of this study was to identify the microbial communities involved in soil formation.DNA was extracted from soil samples from the Llaima volcano in Chile at sites destroyed by lava in different centuries(1640,1751,and 1957).Bacterial and archaeal 16 S r RNA genes were analyzed using quantitative polymerase chain reaction(q PCR)and Illumina Mi Seq sequencing.Results showed that microbial diversity increased with soil age,particularly between the 1751 and 1640 soils.For archaeal communities,Thaumarchaeota was detected in similar abundances in all soils,but Euryarchaeota was rare in the older soils.The analysis of bacterial 16 S r RNA genes showed high abundances of Chloroflexi(37%),Planctomycetes(18%),and Verrucomicrobia(10%)in the youngest soil.Proteobacteria and Acidobacteria were highly abundant in the older soils(16%in 1640 and 15%in 1751 for Acidobacteria;38%in 1640 and 27%in 1751 for Proteobacteria).The microbial profiles in the youngest soils were unusual,with a high abundance of bacteria belonging to the order Ktedonobacterales(Chloroflexi)in the 1957 soil(37%)compared with the 1751(18%)and 1640(7%)soils.In this study,we show that there is a gradual establishment of the microbial community in volcanic soils following an eruption and that specific microbial groups can colonize during the early stages of recovery. 展开更多
关键词 16S rRNA gene extreme environment HIGH-THROUGHPUT SEQUENCING Ktedonobacterales MICROBIAL diversity PIONEER MICROBE recolonization soil formation VOLCANIC deposit
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