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浅谈un-、in-、dis-三个英语否定前缀
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作者 郭卫华 田咏俐 《石家庄理工职业学院学术研究》 2012年第Z1期9-10,23,共3页
英语否定前缀在英语派生词缀中占有重要地位,对它们的熟练掌握能够使英语学习者更加高效、精确地学习和积累英语词汇。本文简要分析了英语中最常见的un-、in-、dis-三个否定前缀的构词特点和语义特征,以期能够对英语学习者的词缀学习和... 英语否定前缀在英语派生词缀中占有重要地位,对它们的熟练掌握能够使英语学习者更加高效、精确地学习和积累英语词汇。本文简要分析了英语中最常见的un-、in-、dis-三个否定前缀的构词特点和语义特征,以期能够对英语学习者的词缀学习和词汇积累起到一定的指导作用。 展开更多
关键词 un- in- dis- 否定前缀
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DIS-401数字音频切换器自动解除报警改造实例
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作者 李健 《西部广播电视》 2020年第24期227-230,共4页
海峡广电的DHX AUDIO DIS-401是一款四选一数字音频切换器。该切换器在信号源中断及信号恢复时都会触发报警,并且只能通过手动操作前面板上的“取消报警”按钮才能解除报警。微波信号源在雨雪天或者大风天气时不稳定,会频繁触发DIS-401... 海峡广电的DHX AUDIO DIS-401是一款四选一数字音频切换器。该切换器在信号源中断及信号恢复时都会触发报警,并且只能通过手动操作前面板上的“取消报警”按钮才能解除报警。微波信号源在雨雪天或者大风天气时不稳定,会频繁触发DIS-401报警,当信号恢复时也需要工作人员手动解除报警,严重影响值班人员正常工作。芜湖发射台技术人员通过增加外接电路,在不影响原设备报警触发条件的前提下,实现当所有信号源均恢复正常时DIS-401自动解除报警功能。 展开更多
关键词 音频切换器 dis-401 报警 自动解除 改造
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Contrastive analysis of prefix dis- and un- in English
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作者 李集团 《International English Education Research》 2014年第5期89-91,共3页
English prefix dis- and tin- are commonly surveyed along with some other negative prefixes. However, there are many cases in which prefix dis- and un- can be attached to the same root, causing the difficulty in distin... English prefix dis- and tin- are commonly surveyed along with some other negative prefixes. However, there are many cases in which prefix dis- and un- can be attached to the same root, causing the difficulty in distinguishing the comprehension of the two prefixes' semantic roles. Considering this issue, this paper endeavors to clarify the respective morphological processes and explain their specific semantic roles. 展开更多
关键词 dis- un- morphological process semantic role
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北京山区油松林光辐射特征及冠层结构参数 被引量:20
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作者 宋子炜 郭小平 +1 位作者 赵廷宁 代巍 《浙江林学院学报》 CAS CSCD 北大核心 2009年第1期38-43,共6页
为了揭示不同径阶油松Pinus tabulaeformis林群落内光辐射状况,以北京市妙峰山实验林场内人工油松林为研究对象,运用WinSCANOPY For Canopy Analysis冠层分析仪采集数据,并结合实地调查,实测了5种不同径阶的油松林群落内光辐射特征及冠... 为了揭示不同径阶油松Pinus tabulaeformis林群落内光辐射状况,以北京市妙峰山实验林场内人工油松林为研究对象,运用WinSCANOPY For Canopy Analysis冠层分析仪采集数据,并结合实地调查,实测了5种不同径阶的油松林群落内光辐射特征及冠层结构参数。结果表明:立地条件相同的情况下,油松林内光辐射随胸径增加呈下降趋势,为14.64~22.43 MJ.m-2.d-1,平均约占冠上总辐射的64.59%。林分开阔度为24.91%~43.77%,并且不同径阶群落之间有明显差别。叶面积指数为2.23~4.50,平均约为3.67。冠层消光系数小于0.20,较小的消光系数对林内灌木层和草本层生长更新具有重要意义。 展开更多
关键词 森林生态学 油松林 光辐射 叶面积指数 消光系数
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湖北黄石、浙江长兴煤山二叠-三叠系界线处火山物质及粘土岩成因探讨 被引量:18
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作者 吴顺宝 任迎新 毕先梅 《地球科学(中国地质大学学报)》 EI CAS CSCD 北大核心 1990年第6期589-595,共7页
本文对湖北黄石、浙江长兴煤山剖面二叠-三叠系界线附近粘土岩层作了碎屑物的分析和测试,并计算了它们的百分含量。与火山活动有关的碎屑主要有石英(其中含六方双锥状的β石英)、锆石、磷灰石、玻璃圆球、铁质圆球及火山灰等。有些样品... 本文对湖北黄石、浙江长兴煤山剖面二叠-三叠系界线附近粘土岩层作了碎屑物的分析和测试,并计算了它们的百分含量。与火山活动有关的碎屑主要有石英(其中含六方双锥状的β石英)、锆石、磷灰石、玻璃圆球、铁质圆球及火山灰等。有些样品中还有电气石、石榴石及锐钛矿等。笔者认为粘土岩层的成因是火山物质在海水中沉积蚀变而成。火山喷出口不在工作区内,生物绝灭的主要原因不是火山活动引起的。 展开更多
关键词 粘土岩 火山物质 二叠纪 三叠纪
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小丛红景天生药学特征研究(简报) 被引量:2
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作者 王莉 刘发央 《甘肃农业大学学报》 CAS CSCD 北大核心 2013年第6期92-94,98,共4页
利用3种溶剂的冷热浸提法,以及根茎切片的形态特征和粉末的显微特征描述,对中药材小丛红景天的生药学特征进行了研究.结果表明:不同溶剂小丛红景天浸出物的含量范围:冷水浸出物0.0968-0.1455 g/g,热水浸出物0.1447-0.2046 g/g;冷醇... 利用3种溶剂的冷热浸提法,以及根茎切片的形态特征和粉末的显微特征描述,对中药材小丛红景天的生药学特征进行了研究.结果表明:不同溶剂小丛红景天浸出物的含量范围:冷水浸出物0.0968-0.1455 g/g,热水浸出物0.1447-0.2046 g/g;冷醇浸出物0.1098-0.1511 g/g,热醇浸出物0.1161-0.1715 g/g;挥发性醚浸出物总量0.0230-0.0452 g/g,其中非挥发性物质0.0167-0.0339 g/g,挥发性物质0.0083-0.0128 g/g. 展开更多
关键词 小丛红景天 浸出物 显微特征 形态特征
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油井水泥分散剂DIS─3的合成及应用
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作者 赵林 董文轩 《江汉石油学院学报》 CSCD 北大核心 1998年第2期54-57,共4页
介绍了一种新型油井水泥分散剂DIS3的合成,室内实验考察了DIS-3对水泥浆性能的影响。结果表明:在DIS3的加量为0.4%~0.6%(基于干水泥质量)时,可使水泥浆的流变性得到明显的改善,且与其它油井水泥外加剂(如... 介绍了一种新型油井水泥分散剂DIS3的合成,室内实验考察了DIS-3对水泥浆性能的影响。结果表明:在DIS3的加量为0.4%~0.6%(基于干水泥质量)时,可使水泥浆的流变性得到明显的改善,且与其它油井水泥外加剂(如降滤失剂和缓凝剂)的配伍性良好,加有DIS3的水泥浆的各项指标均能满足现场固井施工要求。另外,还报道了DIS3在江汉油田3口井固井中的使用效果。 展开更多
关键词 固井 油井 水泥分散剂 dis-3 合成
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Research Progress on MEF2B Gene in Human and Animals
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作者 马晓萌 张莉 杜立新 《Agricultural Science & Technology》 CAS 2016年第11期2477-2482,共6页
Myocyte enhancer factor 2B (MEF2B) gene belongs to myocyte enhancer factor 2 (MEF2) gene family. They are all widely expressed in muscle and nerve tissues of human and animals. MEF2B plays an important role in the... Myocyte enhancer factor 2B (MEF2B) gene belongs to myocyte enhancer factor 2 (MEF2) gene family. They are all widely expressed in muscle and nerve tissues of human and animals. MEF2B plays an important role in the growth of muscle, development and differentiation of nerve system and liver fibrosis. This re- view mainly focused on the structural characteristics, tissue distribution, biological functions and research progress of MEF2B gene in human and animals. 展开更多
关键词 Myocyte enhancer factor 2B (MEF2B) Biological functions Tissue dis- tribution Research progress
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Breeding and Application of Japonica CMS Line Yangfujing 7A with Fine Grain Quality, Disease Resistance and High Combining Ability in Rice
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作者 周根友 夏华 《Agricultural Science & Technology》 CAS 2017年第2期377-379,共3页
Yangfujing 7A, derived from the cross between Xu 9201A and Yangfujing 7 and its successive backcrosses, is a BT-type japonica CMS line developed by the Agricultural Institute of Riparian Region of Jiangsu Province. It... Yangfujing 7A, derived from the cross between Xu 9201A and Yangfujing 7 and its successive backcrosses, is a BT-type japonica CMS line developed by the Agricultural Institute of Riparian Region of Jiangsu Province. It shows good integrat- ed characteristics, stable male sterility, good flowering habits, high out crossing rate, strong disease resistance, fine grain quality (reaching the 1st class of national standards for fine quality rice) and high combining ability. In 2012, it was technically identified in Jiangsu Province. Its F1 hybrid combination Tongyoujingl (Yangfujing 7 A/R98), showing high yield and good grain quality, was registered and released to commercial production by Jiangsu Crop Variety Appraisal Committee in 2013. 展开更多
关键词 Japonica hybrid rice CMS line Yangfujing 7A Fine grain quality dis- ease resistance BREEDING
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云南省森林资源动态变化分析与评价 被引量:6
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作者 胡宗华 《林业调查规划》 2017年第2期87-94,99,共9页
以1978—2012年开展的7次森林资源监测数据为依据,分析云南省35年来森林资源的数量及质量动态变化特点。结果表明,全省森林面积快速增加,林分质量有所下降;森林蓄积持续增长,长消比例逐年提高;人工林分持续增加,经济林发展速度快;竹林... 以1978—2012年开展的7次森林资源监测数据为依据,分析云南省35年来森林资源的数量及质量动态变化特点。结果表明,全省森林面积快速增加,林分质量有所下降;森林蓄积持续增长,长消比例逐年提高;人工林分持续增加,经济林发展速度快;竹林面积总体减少,天然竹呈下降趋势。在对主要森林资源变化趋势进行分析评价的基础上,提出相应对策。 展开更多
关键词 森林资源 动态变化 林分质量 森林蓄积 长消比例 森林资源连续清查 云南省
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查慎行《补注东坡先生编年诗》的文献考证 被引量:1
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作者 何泽棠 《河北工业大学学报(社会科学版)》 2013年第2期25-30,共6页
清初著名学者、诗人查慎行撰有《补注东坡先生编年诗》,该书针对苏诗旧注作了进行了全面的订正、补充。清代宋犖、邵长蘅整理翻刻宋代施元之、顾禧、施宿《注东坡先生诗》而成的《施注苏诗》,对施顾原注常有妄删,查慎行首先针对此现象,... 清初著名学者、诗人查慎行撰有《补注东坡先生编年诗》,该书针对苏诗旧注作了进行了全面的订正、补充。清代宋犖、邵长蘅整理翻刻宋代施元之、顾禧、施宿《注东坡先生诗》而成的《施注苏诗》,对施顾原注常有妄删,查慎行首先针对此现象,补充了施顾注的原文,并对旧注改动引文的原文以迁就作者的现象作了批评与更正。其次,查慎行在《施注苏诗》的《续补遗》二卷的基础上,又依靠宋代及明清的文献,辑得苏轼的佚诗一百二十余首,并对互见于苏轼与他人诗集中的九十首余诗歌作了考证,论证了其中大部分都不是苏轼的作品。《补注东坡先生编年诗》具有很高的文献价值。 展开更多
关键词 查慎行 苏诗补注 辑佚 辨伪 文献价值
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一类年龄结构相关的两性分支过程的灭绝概率(英文)
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作者 邢永胜 《南开大学学报(自然科学版)》 CAS CSCD 北大核心 2014年第2期69-74,共6页
介绍了一类年龄结构相关的两性分支模型,这类模型也可以看做一类特殊的非线性Leslie人口模型.在一夫多妻配对函数条件下,给出了此模型以概率1灭绝的一个充要条件.
关键词 两性分支过程 Leslie矩阵 一夫多妻制配对函数 灭绝概率
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《世说新语》中异构同指之称谓:王夫人、谢夫人——兼谈礼敬称谓词“夫人”的历时使用
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作者 柳士镇 《南京师范大学文学院学报》 2023年第3期154-160,共7页
礼敬称谓词“夫人”在早期使用中如需明确所指何人,“娘家姓氏+夫人”是最为简洁而又具有指别性的称谓方式,故而一直沿用至后世;而《世说新语》中出现的与此异构同指的“夫家姓氏+夫人”用法,可以表明所适家族并彰显夫人地位,明清时期... 礼敬称谓词“夫人”在早期使用中如需明确所指何人,“娘家姓氏+夫人”是最为简洁而又具有指别性的称谓方式,故而一直沿用至后世;而《世说新语》中出现的与此异构同指的“夫家姓氏+夫人”用法,可以表明所适家族并彰显夫人地位,明清时期开始多见。究其各自起因,前者与古人聚族而居密切相关,后者与男尊女卑、嫡尊庶卑有一定联系。而在一个相对封闭的言语环境中,如何选用“夫人”的不同称谓方式,彼此协调而有章可循固然重要,但具有指别性而不致引起误会才是最根本的原则。 展开更多
关键词 异构同指 称谓 王夫人 谢夫人 指别性原则
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矿井供电系统弧光接地过电压形成过程研究 被引量:3
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作者 刘聚财 耿蒲龙 +4 位作者 曲兵妮 宋建成 罗超 李鑫 田敏 《工矿自动化》 北大核心 2018年第4期69-74,共6页
为全面研究矿井供电系统弧光接地过电压形成过程,采用实时数字仿真仪搭建了矿井供电系统模型和间歇性电弧接地模型,分别对工频熄弧、高频熄弧及工频熄弧与高频熄弧同时存在的混合熄弧过程中过电压进行了仿真研究。结果表明:工频熄弧理... 为全面研究矿井供电系统弧光接地过电压形成过程,采用实时数字仿真仪搭建了矿井供电系统模型和间歇性电弧接地模型,分别对工频熄弧、高频熄弧及工频熄弧与高频熄弧同时存在的混合熄弧过程中过电压进行了仿真研究。结果表明:工频熄弧理论条件下暂态过电压最大值略低于历史实测值;高频熄弧理论条件下暂态过电压最大值随电弧重燃次数的增加而增大,且暂态过电压最大值高于历史实测值;混合熄弧情况下,高频熄弧出现次数越多且连续出现时,暂态过电压最大值越高;矿井供电系统发生电弧接地故障时,一般表现为工频熄弧与高频熄弧间隔出现的状态,高频熄弧连续出现3次以上的概率很小。 展开更多
关键词 矿井供电系统 弧光接地过电压 工频熄弧 高频熄弧 混合熄弧
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ANTI-PLANE SHEAR WAVES SCATTERING FROM A PARTIALLY DEBONDED MAGNETO-ELECTRO-ELASTIC CIRCULAR CYLINDRICAL INHOMOGENEITY 被引量:7
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作者 DuJianke ShenYapeng TianWeiping 《Acta Mechanica Solida Sinica》 SCIE EI 2004年第1期1-11,共11页
This article presents an analysis of the scattering of anti-plane shear waves from a single cylindrical inhomogeneity partially bonded to an unbounded magneto-electro-elastic matrix. The magneto-electric permeable bou... This article presents an analysis of the scattering of anti-plane shear waves from a single cylindrical inhomogeneity partially bonded to an unbounded magneto-electro-elastic matrix. The magneto-electric permeable boundary conditions are adopted. The crack opening displacement is represented by Chebyshev polynomials and a system of equations is derived and solved for the unknown coefficients. Some examples are calculated and the results are illustrated. The results show that the COD increases when the piezomagnetic coefficient of the inhomogeneity bonded to the piezoelectric matrix becomes larger, and that the COD decreases when the piezomagnetic coefficient of the matrix with the piezoelectric inhomogeneity increases. 展开更多
关键词 SH waves SCATTERING magneto-electro-elasticity INHOMOGENEITY crack opening dis- placement
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论法定刑升格条件的实质分类 被引量:2
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作者 李庆航 《哈尔滨学院学报》 2017年第12期48-52,共5页
我国法定刑升格条件的传统分类依据注重升格条件要素的表面化差异性,与德日刑法理论强调升格条件的实质内涵区分迥然不同,后者具有简约性与明确性,但在司法实践中仍然存在不足。构成要件的违法性是升格条件的形式区分标准;责任主义原理... 我国法定刑升格条件的传统分类依据注重升格条件要素的表面化差异性,与德日刑法理论强调升格条件的实质内涵区分迥然不同,后者具有简约性与明确性,但在司法实践中仍然存在不足。构成要件的违法性是升格条件的形式区分标准;责任主义原理是升格条件的实质区分标准。区分纯正加重犯与不纯正加重犯,能够更好地从理论架构上解决这种既存的弊病。 展开更多
关键词 法定刑升格条件 形式区分 实质区分 责任主义 纯正加重犯 不纯正加重犯
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Role of on-board discharge in shock wave drag reduction and plasma cloaking 被引量:6
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作者 邱孝明 唐德礼 +2 位作者 孙爱萍 刘万东 曾学军 《Chinese Physics B》 SCIE EI CAS CSCD 2007年第1期186-192,共7页
In the present paper, a physical model is proposed for reducing the problem of the drag reduction of an attached bow shock around the nose of a high-speed vehicle with on-board discharge, to the problem of a balance b... In the present paper, a physical model is proposed for reducing the problem of the drag reduction of an attached bow shock around the nose of a high-speed vehicle with on-board discharge, to the problem of a balance between the magnetic pressure and gas pressure of plane shock of a partially ionized gas consisting of the environmental gas around the nose of the vehicle and the on-board discharge-produced plasma. The relation between the shock strength and the discharge-induced magnetic pressure is studied by means of a set of one-fluid, hydromagnetic equations reformed for the present purpose, where the discharge-induced magnetic field consists of the electron current (produced by the discharge)-induced magnetic field and the partially ionized gas flow-induced one. A formula for the relation between the above parameters is derived. It shows that the discharge-induced magnetic pressure can minimize the shock strength, successfully explaining the two recent experimental observations on attached bow shock mitigation and elimination in a supersonic flow during on-board discharge [Phys. Plasmas 9 (2002) 721 and Phys. Plasmas 7 (2000) 1345]. In addition, the formula implies that the shock elimination leaves room for a layer of higher-density plasma rampart moving around the nose of the vehicle, being favourable to the plasma radar cloaking of the vehicle. The reason for it is expounded. 展开更多
关键词 attached bow shock and magnetohydrodynamic (MHD) drag reduction on-board dis- charges plasma cloaking MHD and fluid equation
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ANTI-PLANE SHEAR CRACK IN A FUNCTIONALLY GRADIENT PIEZOELECTRIC MATERIAL 被引量:2
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作者 Hu Keqiang Zhong Zheng Jin Bo 《Acta Mechanica Solida Sinica》 SCIE EI 2002年第2期140-148,共9页
The main objective of this paper is to study the singular natureof the crack-tip stress and electric displacement field in afunctionally gradient piezoelectric medium having materialcoefficients with a discontinuous d... The main objective of this paper is to study the singular natureof the crack-tip stress and electric displacement field in afunctionally gradient piezoelectric medium having materialcoefficients with a discontinuous derivative. The problem isconsidered for the simplest possible loading and geometry, namely,the anti-plane shear stress and electric displacement in -plane oftwo bonded half spaces in which the crack is parallel to theinterface. 展开更多
关键词 functionally gradient material piezoelectric material stress intensityfactors electric dis- placement intensity factors
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DYNAMICS OF A HEPATITIS B MODEL WITH SATURATED INCIDENCE 被引量:3
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作者 Liya LIU Daqing JIANG +1 位作者 Tasawar HAYAT Bashir AHMAD. 《Acta Mathematica Scientia》 SCIE CSCD 2018年第6期1731-1750,共20页
In this article, we present a hepatitis B epidemic model with saturated incidence.The dynamic behaviors of the deterministic and stochastic system are studied. To thisend, we first establish the local and global stabi... In this article, we present a hepatitis B epidemic model with saturated incidence.The dynamic behaviors of the deterministic and stochastic system are studied. To thisend, we first establish the local and global stability conditions of the equilibrium of thedeterministic model. Second, by constructing suitable stochastic Lyapunov functions, thesufficient conditions for the existence of ergodic stationary distribution as well as extinctionof hepatitis B are obtained. 展开更多
关键词 hepatitis B model Lyapunov function STABILITY stationary distribution ex-tinction
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Does immunohistochemical staining have a clinical impact in early gastric cancer conducted endoscopic submucosal dissection? 被引量:6
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作者 Seong Ran Jeon Joo Young Cho +5 位作者 Gene Hyun Bok Tae Hee Lee Hyun Gun Kim Won Young Cho So Young Jin Yeon Soo Kim 《World Journal of Gastroenterology》 SCIE CAS CSCD 2012年第33期4578-4584,共7页
AIM: To evaluate clinicopathologic parameters and the clinical significance related lymphovascular invasion (LVI) by immunohistochemical staining (IHCS) in endoscopic submucosal dissection (ESD). METHODS: Between May ... AIM: To evaluate clinicopathologic parameters and the clinical significance related lymphovascular invasion (LVI) by immunohistochemical staining (IHCS) in endoscopic submucosal dissection (ESD). METHODS: Between May 2005 and May 2010, a total of 348 lesions from 321 patients (mean age 63 ± 10 years, men 74.6%) with early gastric cancer (EGC) who met indication criteria after ESD were analyzed retrospectively. The 348 lesions were divided into the absolute (n = 100, differentiated mucosal cancer without ulcer ≤ 20 mm) and expanded (n = 248) indica-tion groups after ESD. The 248 lesions were divided into four subgroups according to the expanded ESD indication. The presence of LVI was determined by factor Ⅷ-related antigen and D2-40 assessment. We compared LVI IHCS-negative group with LVI IHCSpositive in each group. RESULTS: LVI by hematoxylin-eosin staining (HES) and IHCS were all negative in the absolute group, while was observed in only the expanded groups. The positive rate of LVI by IHCS was higher than that of LVI by HES (n = 1, 0.4% vs n = 11, 4.4%, P = 0.044). LVI IHCS-positivity was observed when the cancer invaded to the mucosa 3 (M3) or submucosa 1 (SM1) levels, with a predominance of 63.6% in the subgroup that included only SM1 cancer (P < 0.01). In a univariate analysis, M3 or SM1 invasion by the tumor was significantly associated with a higher rate of LVI by IHCS, but no factor was significant in a multivariate analysis. There were no cases of tumor recurrence or metastasis during the median 26 mo follow-up. CONCLUSION: EGCs of the absolute group are immunohistochemically stable. The presence of LVI may be carefully examined by IHCS in an ESD expanded indication group with an invasion depth of M3 or greater. 展开更多
关键词 Gastric cancer Endoscopic submucosal dis- section Immunohistochemical staining Lymphovascu- lar invasion Depth
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