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Rapid improvement of grain weight via highly efficient CRISPR/Cas9-mediated multiplex genome editing in rice 被引量:51
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作者 Rongfang Xu Yachun Yang +5 位作者 Ruiying Qin Hao Li Chunhong Qiu Li Li Pengcheng Wei Jianbo Yang 《Journal of Genetics and Genomics》 SCIE CAS CSCD 2016年第8期529-532,共4页
Most of the important agronomic traits in crop plants, such as yield, quality and stress response, are quantitative and jointly controlled by many genomic loci or major genes. Improving these complex traits depends on... Most of the important agronomic traits in crop plants, such as yield, quality and stress response, are quantitative and jointly controlled by many genomic loci or major genes. Improving these complex traits depends on the combination of beneficial alleles at the quantitative trait loci (QTLs). However, the conventional cross breeding method is extremely time-consuming and laborious for pyramiding multiple QTLs. In certain cases, this approach might be technically difficult because of close linkage between genes separately responsible for desirable and undesirable traits. 展开更多
关键词 Rapid improvement of grain weight via highly efficient CRISPR/Cas9-mediated multiplex genome editing in rice
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谣言实现的社会机制及对信息的治理 被引量:31
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作者 李国武 《社会》 北大核心 2005年第4期143-155,共13页
Rumors are a type of false information, a consequence of an asymmetrical informational structure. This paper focuses on the social mechanisms of rumor fulfilling. Rumors with important contents related to people’s pe... Rumors are a type of false information, a consequence of an asymmetrical informational structure. This paper focuses on the social mechanisms of rumor fulfilling. Rumors with important contents related to people’s personal interests win acceptance through changing people’s expected payoffs, misleading people to the belief that acceptance of the rumor would beneficially outperform rejection of it. Nevertheless, it is risky to believe rumors; therefore, people make their decision whether to believe a rumor or not by referring to other people’s choices. An analysis was performed first within a game model that incorporated the variables of an individual’s expectancy and other people’s impact to predict whether the individual would accept or reject a rumor. Another analysis followed to further examine the functions of some dynamic mechanisms in rumor fulfilling when group pressure and network effects were introduced. Finally, an exploratory discussion on how to prevent rumors and erase their effects via information management strategies was presented. 展开更多
关键词 社会机制 WHETHER structure people ANOTHER further network WOULD 治理 信息 谣言 impact that first model group and type This with make game some when to of are WIN how via on
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LTCC电路加工中的关键技术分析 被引量:26
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作者 赵飞 党元兰 《电子工艺技术》 2013年第1期37-39,共3页
LTCC电路是实现3D立体封装的有效形式之一,从LTCC电路的组成材料出发,概述了LTCC电路的特点及典型的生产流程,提出了LTCC电路加工中需要解决的问题,分析了加工中孔互连、印刷控制、层叠环境、烧结控制和腔体保护加工等关键技术以及不同... LTCC电路是实现3D立体封装的有效形式之一,从LTCC电路的组成材料出发,概述了LTCC电路的特点及典型的生产流程,提出了LTCC电路加工中需要解决的问题,分析了加工中孔互连、印刷控制、层叠环境、烧结控制和腔体保护加工等关键技术以及不同加工方式对产品质量的影响。 展开更多
关键词 LTCC电路 通孔 丝网印刷 层叠 烧结 腔体
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4种不同检查方法在宫颈癌筛查中的临床应用价值 被引量:26
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作者 李瑞珍 乌兰娜 +12 位作者 刘植华 王倩 李俊华 李晴 李霓 刘志红 石菊芳 张长淮 周艳秋 刘彬 翁雷明 吴瑞芳 乔友林 《中国肿瘤临床》 CAS CSCD 北大核心 2009年第1期1-4,共4页
目的:了解4种不同检查方法在宫颈癌筛查中的临床应用价值。方法:采用第二代杂交捕获技术(hyhrid capture 2,Hc—Ⅱ)检测13种高危型人乳头瘤病毒(human papillomavirus,HPV)、薄层液基细胞学技术(Liquid—hased cytologytest,... 目的:了解4种不同检查方法在宫颈癌筛查中的临床应用价值。方法:采用第二代杂交捕获技术(hyhrid capture 2,Hc—Ⅱ)检测13种高危型人乳头瘤病毒(human papillomavirus,HPV)、薄层液基细胞学技术(Liquid—hased cytologytest,LCT)检测宫颈脱落细胞、醋酸肉眼检查(visual inspection with acetic acid,VIA)和阴道镜检查4种方法对2004年11月~2004年12月深圳南山区华侨城区域15~59岁有性生活女性共1137例进行盲法同步宫颈癌筛查。对阴道镜检查异常或可疑异常者行阴道镜下直接活检;对HPV阳性并且LCT≥未明确诊断意义的不典型鳞状上皮细胞(atypical squamous cells of undetetemined sign,Ascus),或HPV阴性但LCT≥低度鳞状上皮内病变(low grade squamous intraepithelial lesion,LSIL)的妇女再次行阴道镜下活组织病理学检查,以病理结果作为验证4种检查方法的金标准。结果:共取病理122例。病理结果证实该人群中无宫颈癌病例:子宫颈上皮内瘤变(cervical intraepithlial neoplasia。CIN)Ⅲ级3例,CINⅡ级11例,CINⅠ级36例;慢性宫颈炎和鳞状上皮化生69例;正常宫颈3例。人群的高危HPV总检出率为14.0%;LCT阳性率为12.6%;VIA阳性率为12.5%;阴道镜阳性率为13,6%。随宫颈病变级别升高,高危HPV感染率及LCT阳性率均呈趋势性增加(P〈0.005);VIA和阴道镜阳性率在各级宫颈病变中无统计学差异,但在宫颈病变组阳性检出率明显高于正常宫颈组。高危HPV对宫颈高度病变的敏感性、特异性、准确性、阳性预测值、阴性预测值、阳性似然比和阴性似然比分别为100%、87.1%、87.3%、8.8%、100%、7.6%和0;LCT以上各指标分别为92.9%、88.4%、88.5%、9.1%、99.9%、8.0%和8.0%;VIA以上各指标分别为35.7%、96.0%、95.3%、10.0%、99.2%、8.9%和67.0%;阴道镜� 展开更多
关键词 宫颈肿瘤 杂交捕获 薄层液基细胞学 醋酸肉眼检查 阴道镜
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高速PCB的过孔设计 被引量:14
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作者 袁子建 吴志敏 高举 《电子工艺技术》 2002年第4期158-159,163,共3页
在高速PCB设计中 ,过孔设计是一个重要因素 ,它由孔、孔周围的焊盘区和POWER层隔离区组成 ,通常分为盲孔、埋孔和通孔三类。在PCB设计过程中通过对过孔的寄生电容和寄生电感分析 ,总结出高速PCB过孔设计中的一些注意事项。
关键词 过孔 寄生电容 寄生电感 非穿导孔技术
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电子墨水微胶囊及电泳显示原型器件的制备 被引量:17
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作者 荣宇 吴刚 +1 位作者 陈红征 汪茫 《高等学校化学学报》 SCIE EI CAS CSCD 北大核心 2005年第5期982-984,F011,共4页
TiO2 particles coated with polystyrene which were prepared via in situ polymerization and oil green dye were dispersed in tetrachloroethylene and xylene, the mixture came to be electrophoretic ink and was encapsulated... TiO2 particles coated with polystyrene which were prepared via in situ polymerization and oil green dye were dispersed in tetrachloroethylene and xylene, the mixture came to be electrophoretic ink and was encapsulated in to microcapsules by complex coacervation from gelatin and a hydrolyzed copolymer of styrene and maleic anhydride(SMA). It was demonstrated that the membranes of the microcapsules were formed from nano sized coacervate droplets resulting from gelation and hydrolyzed SMA, which leads to a compact membrane structure. Microcapsules were characterized in terms of microstructure, morphologies by scanning electron microscopy(SEM). Electrophoretic display prototype was prepared by coating electrophoretic ink microcapsules slurry on ITO glass with nearly single layer and sealed by UV curable adhesives. The characters “Zheda” in Chinese was firstly displayed at a low volt 9 V D.C.. 展开更多
关键词 电泳显示 电子墨水 微胶囊 complex compact DISPLAY 制备 器件 原型 with and green was the TiO2 nano in via OIL to SMA ITO The
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论中国西南地区早期佛像 被引量:22
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作者 罗二虎 《考古》 CSSCI 北大核心 2005年第6期66-73,共8页
中国西南地区在东汉晚期至蜀汉前期至蜀汉前期已出现早期佛像,主要见到随葬钱树上的铜或陶质佛像,也有部分崖墓石刻画像中的石佛像,它们很可能代表了中国内地最早阶段的典型佛像。早期佛像在西南地区流行应与本土传统的升仙信仰有关,可... 中国西南地区在东汉晚期至蜀汉前期至蜀汉前期已出现早期佛像,主要见到随葬钱树上的铜或陶质佛像,也有部分崖墓石刻画像中的石佛像,它们很可能代表了中国内地最早阶段的典型佛像。早期佛像在西南地区流行应与本土传统的升仙信仰有关,可能是经由"丝绸之路"传入川西地区后在此区域内传播。 展开更多
关键词 中国西南地区 culture China 佛像 早期 the HAVE first and WORKS data that LATE from some form very MUST with to The are of via MAY on
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0~5月龄婴儿母乳喂养困难调查及影响因素研究 被引量:20
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作者 叶芳 林荭 +4 位作者 陈杰 刘芳 范钦颖 张勇 王琳 《中国儿童保健杂志》 CAS 2018年第3期290-293,共4页
目的调查和分析北京市某城区婴儿母乳喂养困难的现状及影响因素,为促进母乳喂养的干预措施提供依据。方法选取2016年1月1日-12月31日在本院儿童保健门诊进行常规体检,进行母乳喂养的120例婴儿及母亲作为研究对象,采用统一问卷(一般情况... 目的调查和分析北京市某城区婴儿母乳喂养困难的现状及影响因素,为促进母乳喂养的干预措施提供依据。方法选取2016年1月1日-12月31日在本院儿童保健门诊进行常规体检,进行母乳喂养的120例婴儿及母亲作为研究对象,采用统一问卷(一般情况、产科史、Via Christi母乳喂养评价量表)进行横断面调查研究。结果 120例研究对象Via Christi量表的平均得分为8.2±1.4,70%的婴儿仅存在轻微或不存在母乳喂养困难,30%的婴儿存在中度母乳喂养困难。量表5个条目中得分最低的两项客观指标分别为"含接到有效吸吮之间持续时间"(1.0±0.9)和"乳头含接"(1.7±0.4)。影响因素的分析结果显示,出生后1周内进行纯母乳喂养[OR=0.140,95%CI:(0.024~0.802)]和顺产[OR=0.343,95%CI:(0.174~0.879)]是母乳喂养的保护因素(P均<0.05),流动人口[OR=8.679,95%CI:(1.558~48.338)]和早产[OR=5.470,95%CI:(1.216~25.030)]是母乳喂养的危险因素(P均<0.05)。结论母乳喂养过程中发生问题最多的是"乳头含接"和"含接后到有效吸吮"这两个环节;流动人口、出生后1周内混合喂养、早产儿和剖宫产是发生母乳喂养困难的危险因素,在临床实际工作中应给予重点关注。 展开更多
关键词 母乳喂养 via Christi母乳喂养评价量表 婴儿
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High-efficiency breeding of early-maturing rice cultivars via CRISPR/Cas9-mediated genome editing 被引量:21
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作者 Xiufeng Li Wenjia Zhou +7 位作者 Yuekun Ren Xiaojie Tian Tianxiao Lv Zhenyu Wang Jun Fang Chengcai Chu Jie Yang Qingyun Bu 《Journal of Genetics and Genomics》 SCIE CAS CSCD 2017年第3期175-178,共4页
Rice is a staple food for more than half of the human population.It has been estimated that by 2030,40%more rice needs to be produced in order to meet the growing demand(Khush,2005).One of the strategies to improve ... Rice is a staple food for more than half of the human population.It has been estimated that by 2030,40%more rice needs to be produced in order to meet the growing demand(Khush,2005).One of the strategies to improve rice productivity is to enlarge rice growth areas, such as the northward expansion of the growth region in Heilongjiang Province, the northernmost region of China (Li et al., 2015). However, the northward cultivation is accompanied with daylength extension and temperature decrease, which are unfavor- able for rice, a tropical short-day plant, to complete flowering and seed setting. Thus, the need for early-maturing rice cultivars with extremely low photoperiod sensitivity is urgent. 展开更多
关键词 In THAN High-efficiency breeding of early-maturing rice cultivars via CRISPR/Cas9-mediated genome editing
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改良Valdivia体位经皮肾镜取石术和开放手术取石术对肾结石患者应激反应及炎性指标的影响 被引量:21
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作者 赵水平 陈霜 +3 位作者 张鑫圣 王慧 刘世雄 李欣 《中国药物与临床》 CAS 2019年第11期1837-1839,共3页
肾结石是一种由于晶体物质或有机物质沉积于肾脏造成肾区疼痛的疾病,在临床中较为常见。对于结石直径较小的肾脏结石能够通过药物缓解,但对于结石较大且经药物治疗无法缓解的肾结石患者临床中多采用外科手术治疗[1]。开放手术取石术是... 肾结石是一种由于晶体物质或有机物质沉积于肾脏造成肾区疼痛的疾病,在临床中较为常见。对于结石直径较小的肾脏结石能够通过药物缓解,但对于结石较大且经药物治疗无法缓解的肾结石患者临床中多采用外科手术治疗[1]。开放手术取石术是临床中传统的手术方式,但是由于手术切口较大,患者容易产生手术应激反应,而且容易引起炎症反应[2]。改良Valdivia体位经皮肾镜取石术(PCNL)是目前临床中常用的微创治疗方式,手术创伤较少[3]。 展开更多
关键词 经皮肾镜取石术 手术应激反应 开放手术 肾结石 via LDI 炎性指标 患者
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东北亚地区建立自由贸易区(FTA)的现状与趋势 被引量:17
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作者 王胜今 于潇 《东北亚论坛》 CSSCI 2007年第4期3-6,共4页
2000年以来,东北亚有关国家建立双边自由贸易协定(FTA)的步伐明显加快,但在东北亚地区内部,除日本和韩国外其他国家之间近期内建立FTA的可能性很低,特别是对中日、中韩经济贸易关系非常紧密的国家之间建立FTA的可能性较小,缺乏政治互信... 2000年以来,东北亚有关国家建立双边自由贸易协定(FTA)的步伐明显加快,但在东北亚地区内部,除日本和韩国外其他国家之间近期内建立FTA的可能性很低,特别是对中日、中韩经济贸易关系非常紧密的国家之间建立FTA的可能性较小,缺乏政治互信是导致该地区内部FTA发展缓慢的主要原因。 展开更多
关键词 东北亚 via 区域合作
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Periodontitis-induced systemic inflammation exacerbates atherosclerosis partly via endothelial–mesenchymal transition in mice 被引量:17
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作者 Jin Sook Suh Sol Kim +3 位作者 Kristina I.Bostrom Cun-Yu Wang Reuben H.Kim No-Hee Park 《International Journal of Oral Science》 SCIE CAS CSCD 2019年第3期201-212,共12页
Growing evidence suggests close associations between periodontitis and atherosclerosis.To further understand the pathological relationships of these associations,we developed periodontitis with ligature placement arou... Growing evidence suggests close associations between periodontitis and atherosclerosis.To further understand the pathological relationships of these associations,we developed periodontitis with ligature placement around maxillary molars or ligature placement in conjunction with Porphyromonas gingivalis lipopolysaccharide injection at the ligature sites (ligature/P.g.LPS) in Apolipoprotein E knock out mice and studied the atherogenesis process in these animals.The mice were fed with high fat diet for 11 weeks and sacrificed for analyzing periodontitis,systemic inflammation,and atherosclerosis.Controls did not develop periodontitis or systemic inflammation and had minimal lipid deposition in the aortas,but mice receiving ligature or ligature/P.g.LPS showed severe periodontitis,systemic inflammation,and aortic plaque formation.The aortic plaque contained abundant macrophages and cells expressing both endothelial and mesenchymal cell markers.The severity of periodontitis was slightly higher in mice receiving ligature/P.g.LPS than ligature alone,and the magnitude of systemic inflammation and aortic plaque formation were also notably greater in the mice with ligature/P.g.LPS.These observations indicate that the development of atherosclerosis is due to systemic inflammation caused by severe periodontitis.In vitro,P.g.LPS enhanced the secretion of pro-inflammatory cytokines from macrophages and increased the adhesion of monocytes to endothelial cells by upregulating the expression of adhesion molecules from endothelial cells.Moreover,secretory proteins,such as TNF-α,from macrophages induced endothelial–mesenchymal transitions of the endothelial cells.Taken together,systemic inflammation induced by severe periodontitis might exacerbate atherosclerosis via,in part,causing aberrant functions of vascular endothelial cells and the activation of macrophages in mice. 展开更多
关键词 via AORTIC cells TNF-α did HAD but was
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美国积极心理学倡导的“优秀品质和美德” 被引量:17
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作者 陈虹 张婷婷 《中小学心理健康教育》 2009年第5期18-21,共4页
美国积极心理学创始人之一塞里格曼所推出的真正幸福论认为“幸福”这个词很难有科学的定义,它应囊括三个领域,即:快乐生活、充实生活和有意义的生活。塞里格曼在他设计的有关“快乐生活”的练习中包括“乐观”和“希望”的干预练习... 美国积极心理学创始人之一塞里格曼所推出的真正幸福论认为“幸福”这个词很难有科学的定义,它应囊括三个领域,即:快乐生活、充实生活和有意义的生活。塞里格曼在他设计的有关“快乐生活”的练习中包括“乐观”和“希望”的干预练习,其中包括“运用你的特长”。“运用你的特长”要求参与者填写VIA—IS特长问卷后分析出自身的五个优点,然后设法把它们在日常生活中运用起来。这个VIA—IS特长问卷是根据塞里格曼的优秀品质和美德理论编写的。 展开更多
关键词 美国 真正幸福论 via strengths SURVEY 优秀品质
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An organizational model and border port hinterlands for the China-Europe Railway Express 被引量:17
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作者 王姣娥 焦敬娟 马丽 《Journal of Geographical Sciences》 SCIE CSCD 2018年第9期1275-1287,共13页
Facilities connectivity is a priority area for implementing the Belt and Road Initiative(BRI). The "China-Europe Railway Express"(CER Express) mode of transport organization links China with Europe by fast-t... Facilities connectivity is a priority area for implementing the Belt and Road Initiative(BRI). The "China-Europe Railway Express"(CER Express) mode of transport organization links China with Europe by fast-track cargo rail. A major instance of facilities connectivity related to this project is an important practical and symbolic instance of BRI transport cooperation. The strategic significance of the CER Express and a number of operational issues are outlined, as are the implications of limited market potential for costs and competitiveness. A "hub-and-spoke" organizational model that can generate scale economies and reduce costs is proposed. To examine the establishment of an organizational model of this kind, the economic hinterlands of Alashankou, Erenhot, and Manzhouli are identified under high-, mediumand low-cost scenarios using an analytical methodology that determines distance and economic costs, and a number of transport hubs(that include Harbin, Zhengzhou, and Lanzhou) are identified. The results found that the cost of the routes from 314 Chinese cities to Moscow is the lowest via Manzhouli in the high-and medium-cost scenarios, but the routes change via Erenhot in the low-cost scenario. A number of policy recommendations should follow up. 展开更多
关键词 China-Europe Railway Express cross-border transportation via land routes Belt and Road Initiative facilities connectivity hub-and-spoke model
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中国推进中日韩自由贸易区建设的策略思考 被引量:15
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作者 于晓燕 《南开学报(哲学社会科学版)》 CSSCI 北大核心 2011年第4期19-25,共7页
中日韩自由贸易区联合研究即将结束并有望在2012年进入政府谈判阶段。中日韩三国近年来在商品及服务贸易、投资以及经济合作领域保持了高度密切的联系,并存在巨大的合作潜力。该自由贸易区的建设将为中国创造更为广阔和稳定的市场以及... 中日韩自由贸易区联合研究即将结束并有望在2012年进入政府谈判阶段。中日韩三国近年来在商品及服务贸易、投资以及经济合作领域保持了高度密切的联系,并存在巨大的合作潜力。该自由贸易区的建设将为中国创造更为广阔和稳定的市场以及可观的经济利益,但其意义不止于此。应从更加宏观的视角认识该自由贸易区对于中国实施区域经济合作战略,在亚太地区经济一体化进程中争取主动地位的重要战略意义,并采取积极和务实的态度推进该自由贸易区的谈判与建设工作。 展开更多
关键词 中日韩 自由贸易区 中国 区域经济合作 战略
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Periodontitis may induce gut microbiota dysbiosis via salivary microbiota 被引量:13
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作者 Jun Bao Lili Li +5 位作者 Yangheng Zhang Min Wang Faming Chen Shaohua Ge Bin Chen Fuhua Yan 《International Journal of Oral Science》 SCIE CAS CSCD 2022年第3期349-359,共11页
The aim of this study was to identify whether periodontitis induces gut microbiota dysbiosis via invasion by salivary microbes.First,faecal and salivary samples were collected from periodontally healthy participants(P... The aim of this study was to identify whether periodontitis induces gut microbiota dysbiosis via invasion by salivary microbes.First,faecal and salivary samples were collected from periodontally healthy participants(PH group,n=16)and patients with severe periodontitis(SP group,n=21)and analysed by 16S ribosomal RNA sequencing.Significant differences were observed in both the faecal and salivary microbiota between the PH and SP groups.Notably,more saliva-sourced microbes were observed in the faecal samples of the SP group.Then,the remaining salivary microbes were transplanted into C57BL6/J mice(the C-PH group and the C-SP group),and it was found that the composition of the gut microbiota of the C-SP group was significantly different from that of the C-PH group,with Porphyromonadaceae and Fusobacterium being significantly enriched in the C-SP group.In the colon,the C-SP group showed significantly reduced crypt depth and zonula occludens-1 expression.The m RNA expression levels of pro-inflammatory cytokines,chemokines and tight junction proteins were significantly higher in the C-SP group.To further investigate whether salivary bacteria could persist in the intestine,the salivary microbiota was stained with carboxyfluorescein diacetate succinimidyl ester and transplanted into mice.We found that salivary microbes from both the PH group and the SP group could persist in the gut for at least 24 h.Thus,our data demonstrate that periodontitis may induce gut microbiota dysbiosis through the influx of salivary microbes. 展开更多
关键词 Periodontitis may induce gut microbiota dysbiosis via salivary microbiota
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高速多层板过孔分析与仿真 被引量:14
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作者 刘烨铭 曹跃胜 《计算机工程与设计》 CSCD 北大核心 2008年第3期713-715,758,共4页
过孔效应已经成为制约高速PCB设计的关键因素之一,介绍了高速PCB设计中过孔对信号完整性的影响,尤其对于高速多层板过孔的特性进行了详细分析,并采用软件对多层印刷电路板上的过孔模型进行了仿真,着重分析了Stub对过孔传输特性所产生的... 过孔效应已经成为制约高速PCB设计的关键因素之一,介绍了高速PCB设计中过孔对信号完整性的影响,尤其对于高速多层板过孔的特性进行了详细分析,并采用软件对多层印刷电路板上的过孔模型进行了仿真,着重分析了Stub对过孔传输特性所产生的影响,以及Back-drilling工艺的优势,仿真结果对高速PCB设计具有实际指导作用。 展开更多
关键词 过孔 高速印刷电路板 信号完整性 反钻 过孔短柱
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Method for array gain and phase uncertainties calibration based on ISM and ESPRIT 被引量:11
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作者 Liao Bin Liao Guisheng 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2009年第2期223-228,共6页
A new method for array calibration of array gain and phase uncertainties, which severely degrade the performance of spatial spectrum estimation, is presented. The method is based on the idea of the instrumental sensor... A new method for array calibration of array gain and phase uncertainties, which severely degrade the performance of spatial spectrum estimation, is presented. The method is based on the idea of the instrumental sensors method (ISM), two well-calibrated sensors are added into the original array. By applying the principle of estimation of signal parameters via rotational invariance techniques (ESPRIT), the direction-of-arrivals (DOAs) and uncertainties can be estimated simultaneously through eigen-decomposition. Compared with the conventional ones, this new method has less computational complexity while has higher estimation precision, what's more, it can overcome the problem of ambiguity. Both theoretical analysis and computer simulations show the effectiveness of the proposed method. 展开更多
关键词 array calibration array gain and phase uncertainties direction of arrival instrumental sensors method estimation of signal parameters via rotationaJ invariance techniques.
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基于Myrinet的高性能VIA设计与实现 被引量:6
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作者 陈渝 焦振强 +2 位作者 谢军 都志辉 李三立 《软件学报》 EI CSCD 北大核心 2003年第2期285-292,共8页
Virtual interface architecture(VIA)建立了一种低延迟、高带宽的通信模型,定义了集群系统中用户层高性能通信规范的标准.通过分析VIA的进展、原理及当前的实现,在Myrinet上设计并实现了一个符合VIA规范的高性能用户层通信软件MyVIA.... Virtual interface architecture(VIA)建立了一种低延迟、高带宽的通信模型,定义了集群系统中用户层高性能通信规范的标准.通过分析VIA的进展、原理及当前的实现,在Myrinet上设计并实现了一个符合VIA规范的高性能用户层通信软件MyVIA.首先定义了MyVIA的设计原理和框架;然后针对MyVIA实现的不同层次,通过与BerkeleyVIA的比较,提出了UTLB、连续物理内存和可变长NIC内存管理、基于资源和DMA chain的流水线处理、物理描述子环和物理描述子动态缓存等多项优化技术.通过性能的分析比较表明,MyVIA发送4KB数据包时的带宽可达到250MB/s,最小单边延迟为8.46ms.与目前其他VIA实现相比,MyVIA的性能有了较为显著的提高. 展开更多
关键词 via 软件设计 用户层通信软件 Myrinet网络平台 虚拟接口结构
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高速SERDES的多板传输技术与SI仿真 被引量:12
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作者 曹跃胜 胡军 刘烨铭 《计算机工程与科学》 CSCD 2008年第8期139-143,共5页
随着SERDES传输速率达到10Gbps,高速PCB上的信号传输尤其是多板间传输,已经成为高速设计的实现难点。高速PCB及其要素的设计、分析、仿真,以及高速传输链路的设计优化,是多板SERDES传输实现更高速率的关键。本文对高速串行SERDES的原理... 随着SERDES传输速率达到10Gbps,高速PCB上的信号传输尤其是多板间传输,已经成为高速设计的实现难点。高速PCB及其要素的设计、分析、仿真,以及高速传输链路的设计优化,是多板SERDES传输实现更高速率的关键。本文对高速串行SERDES的原理和架构进行了深入分析,研究了多板传输中影响信号完整性(SI)的关键因素和建模优化方法;最后,针对实验电路板建立了多板仿真模型,对实际的SERDES差分网络进行了仿真分析。 展开更多
关键词 传输线 特性阻抗 信号完整性 连接器 过孔 高速串行传输 IBIS SPICE 多板分析 电路仿真
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