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中国煤层气水平井钻完井技术研究进展 被引量:4
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作者 鲜保安 高德利 +5 位作者 徐凤银 毕延森 李贵川 王京光 张洋 韩金良 《石油学报》 EI CAS CSCD 北大核心 2023年第11期1974-1992,共19页
为了适应中国煤层复杂的地质条件与储层物性特征,水平井钻完井技术不断得以深化研究与发展,围绕"井工厂"形成了井型优化、储层保护、导向钻井和水平井适应性完井技术,逐渐成为中国煤层气高效开发的重要措施。为煤层气高效开... 为了适应中国煤层复杂的地质条件与储层物性特征,水平井钻完井技术不断得以深化研究与发展,围绕"井工厂"形成了井型优化、储层保护、导向钻井和水平井适应性完井技术,逐渐成为中国煤层气高效开发的重要措施。为煤层气高效开发提供钻完井工程方面的技术支持,通过概述中国煤层气水平井钻完井技术研究进展,重点介绍了煤层气水平井完井技术3项研究成果:①形成了煤层水平井双管柱完井与增透一体化技术,在沁水盆地南部应用400余口井,并取得技术与产量突破;开展了井壁煤岩径向循环载荷实验,通过CT扫描技术检测了煤岩裂缝形成与扩展;基于煤岩双孔隙结构、非均质性和孔隙多尺度特征,修正了径向循环载荷下煤岩损伤变量计算模型。②提出了径向水平井柔性筛管液压驱动下入方法,优化设计了完井管柱结构与配套工具,建立了管柱-液压耦合计算模型,以深部煤层径向水平井为算例,计算两种完井管柱结构的最大下入长度分别达到381 m、655 m,为径向井筛管完井提供技术指导。③提出了复杂煤体结构煤层水平井分段复合完井增透方法,数值模拟了循环冲击波辅助水力压裂煤层裂缝扩展规律,通过该技术使停产井增产至2000 m3/d。最后,概括了深部煤层气水平井钻完井发展技术要点,以大型"井工厂"为核心的配套技术将成为煤层气开发降本增效的关键技术,多约束条件轨道优化设计和控制技术是深部煤层水平井优快钻井的技术保障,水平井多元化完井增产技术将成为中国深部煤层气高效开发的新模式。 展开更多
关键词 煤层气 水平井钻完井 大型井工厂 复合完井增产 深部煤层
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煤层气储层伤害机理与水平井双层管柱筛管完井技术 被引量:6
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作者 鲜保安 张龙 +6 位作者 哈尔恒·吐尔松 喻鹏 王凯 张亚飞 张洋 王三帅 李宗源 《煤田地质与勘探》 CAS CSCD 北大核心 2022年第9期122-129,共8页
煤储层具有高吸附性、低渗透性、易压缩与易破碎的特征,煤层气水平井钻完井过程中常常造成煤储层伤害,导致煤层渗透率和单井煤层气产量大幅度降低。通过实验分析,揭示水平井钻完井液中的固相颗粒、流体流动诱导产生的固相成分对煤储层... 煤储层具有高吸附性、低渗透性、易压缩与易破碎的特征,煤层气水平井钻完井过程中常常造成煤储层伤害,导致煤层渗透率和单井煤层气产量大幅度降低。通过实验分析,揭示水平井钻完井液中的固相颗粒、流体流动诱导产生的固相成分对煤储层微裂隙堵塞成因,阐明煤层气水平井钻完井中储层伤害的机理。在此基础上,提出水平井双层管柱筛管完井技术,分析其减轻煤储层伤害的机理,即通过冲管水力冲击作用消除水平井壁钻井液泥饼,清除井壁附近堵塞微裂隙煤粉,并在近井地带产生应力增渗作用。相对于煤层气常规的多分支水平井及分段压裂水平井,水平井双层管柱筛管完井的稳定日产气量、稳产周期均大幅提升。该技术在沁水盆地南部部分区域推广应用显示,3号煤层气井平均日产气量提升到20000 m^(3),同时实现15号煤层气的开发突破,平均日产气量提升到10000 m^(3)以上。研究成果对于降低煤层气水平井钻完井过程中的储层伤害,提高煤层气井产量具有重要的理论和实践意义。 展开更多
关键词 煤层气水平井 储层伤害机理 双层管柱筛管 完井技术 钻完井液
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新疆阜康矿区煤层气双管柱筛管完井机理与适用性研究 被引量:1
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作者 张龙 王一兵 +6 位作者 鲜保安 张亚飞 谭章龙 哈尔恒·吐尔松 孙昊 王冠 张锦涛 《油气藏评价与开发》 CSCD 2022年第4期633-642,共10页
新疆阜康矿区煤储层具有煤层倾角大、厚度大、煤层多、构造复杂等特征,矿区煤层气规模开发进展缓慢,亟需寻找合适的煤层气地质工程一体化开发技术,为新疆煤层气开发提供有力支撑。双管柱筛管完井技术集完井增产一体化,已在沁水盆地推广... 新疆阜康矿区煤储层具有煤层倾角大、厚度大、煤层多、构造复杂等特征,矿区煤层气规模开发进展缓慢,亟需寻找合适的煤层气地质工程一体化开发技术,为新疆煤层气开发提供有力支撑。双管柱筛管完井技术集完井增产一体化,已在沁水盆地推广应用超过400口煤层气水平井。双管柱筛管完井技术从水力冲击作用、清除煤粉、钻井液化学破胶、应力增渗等4个方面对煤层气水平井进行增产改造,助力阜康矿区煤层气高效开发。基于双管柱筛管完井技术特点,从储层煤体结构优势、储层渗透率恢复优势、储层孔裂隙拓展优势、储层构造优势4个方面论述了该技术对于阜康矿区煤层气开发的适用性与应用机理,对新疆类似储层地质条件下的煤层气高效开发具有指导和借鉴意义。 展开更多
关键词 煤层气 阜康矿区 双管柱 筛管完井 适应性研究
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低渗煤储层背景下高渗带主控地质因素及模式 被引量:2
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作者 张洲 鲜保安 +2 位作者 连小华 王青川 周敏 《天然气地球科学》 EI CAS CSCD 北大核心 2018年第11期1656-1663,共8页
沁水盆地南部郑庄区块相邻煤层气井地质条件和开发工艺基本相同,但产气量却有巨大差异。针对这一现象,利用构造裂隙填图、煤体结构测井解释、裂隙特征压裂曲线反演、构造曲率分析等技术,分析了煤储层裂隙系统的发育特征;从古地应力场演... 沁水盆地南部郑庄区块相邻煤层气井地质条件和开发工艺基本相同,但产气量却有巨大差异。针对这一现象,利用构造裂隙填图、煤体结构测井解释、裂隙特征压裂曲线反演、构造曲率分析等技术,分析了煤储层裂隙系统的发育特征;从古地应力场演化、原地应力测试入手,讨论了煤储层裂隙优势方向上有效应力对渗透率的控制作用。研究认为,煤储层裂隙系统的发育特征和优势裂隙方向的有效应力,是低渗背景下高渗带的主控地质因素。建立了3种渗透率发育地质模式:一是裂隙系统发育适中与有效应力匹配型,煤储层渗透率高,煤层气井产量高;二是煤储层裂隙系统过度发育型,无论有效应力适中或者过高,两者条件均不匹配,储层渗透率较低,产气量低;三是有效应力过高型,无论裂隙发育程度如何,均会导致煤储层渗透率较低,产气量低。研究成果对于相似地质条件的煤层气区块内高渗带预测具有借鉴意义。 展开更多
关键词 高渗带 裂隙系统 有效应力 匹配模式 形成模式
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中国煤层气高效开发井型与钻完井技术进展 被引量:25
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作者 高德利 毕延森 鲜保安 《天然气工业》 EI CAS CSCD 北大核心 2022年第6期1-18,共18页
较之于美国、澳大利亚、加拿大等国家,中国的煤层气储层具有低地层压力、低渗透率、低含气饱和度及强非均质性等基本特征,增加了储层改造的难度,制约了煤层气单井产量与采收率的提高。为了给中国煤层气水平井工程技术发展提供借鉴与支持... 较之于美国、澳大利亚、加拿大等国家,中国的煤层气储层具有低地层压力、低渗透率、低含气饱和度及强非均质性等基本特征,增加了储层改造的难度,制约了煤层气单井产量与采收率的提高。为了给中国煤层气水平井工程技术发展提供借鉴与支持,针对我国煤层气高效开发所面临的工程技术难题,综述了国内外煤层气水平井钻完井技术研究及应用进展,介绍了煤层气井型设计与井身结构优化、井眼轨迹控制、井壁稳定、优化完井与储层保护等一系列技术,讨论了水平井双管柱筛管完井与洗井增产、径向水平井筛管完井及磁导向钻井等新技术及其适应性,提出了地下“井工厂”绿色开发模式以及深地煤层气与煤炭一体化绿色开发之道。结论认为:①针对我国煤层地质条件与地表环境,在进一步精细化高煤阶水平井钻井与完井技术的同时,需要兼顾煤系气综合开发;②加强中—低煤阶与碎软煤层水平井钻完井技术创新研究,深入探索复杂煤层气藏高效开发模式;③针对我国深地煤矿、低品位煤矿及薄煤层等非常规煤矿绿色高效开发面临的重大技术难题,有必要积极探索地下“井工厂”与非常规能矿原位转化开发模式,力求实现深部煤层气与煤炭一体化绿色高效开发的目标;④高质量推进我国能源低碳绿色转型,既要保障国家能源安全,又要实现“碳达峰和碳中和”战略目标。 展开更多
关键词 中国煤层气 水平井 钻井与完井 钻井液与储层保护 地下“井工厂” 煤层气与煤炭一体化绿色高效开发
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高龄产妇不良妊娠结局200例影响因素分析 被引量:21
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作者 咸保花 陈建梅 《蚌埠医学院学报》 CAS 2020年第6期792-794,798,共4页
目的:分析200例高龄产妇不良妊娠结局的影响因素。方法:选取200例高龄产妇,收集产妇的妊娠结局,统计不良妊娠结局发生情况,并分析影响高龄产妇发生不良妊娠结局的因素。结果:200例高龄产妇的不良妊娠结局发生率为19.00%,依次为低体质量... 目的:分析200例高龄产妇不良妊娠结局的影响因素。方法:选取200例高龄产妇,收集产妇的妊娠结局,统计不良妊娠结局发生情况,并分析影响高龄产妇发生不良妊娠结局的因素。结果:200例高龄产妇的不良妊娠结局发生率为19.00%,依次为低体质量儿(31.58%)、早产儿(26.32%)、新生儿窒息(15.79%)、巨大儿(15.79%)、新生儿畸形(5.26%)、新生儿死亡(5.26%);影响高龄产妇不良妊娠结局的单因素包括流产史、不良妊娠习惯、计划怀孕、妊娠合并症、妊娠并发症、被动吸烟、多胎妊娠以及孕前疾病史(P<0.05~P<0.01);logistic回归多因素分析表明,流产史、妊娠合并症、妊娠并发症、被动吸烟、多胎妊娠、孕前疾病史均是高龄产妇不良妊娠结局的危险因素(P<0.05~P<0.01)。结论:高龄产妇的不良妊娠结局发生率较高,流产史、妊娠合并症、妊娠并发症、被动吸烟、多胎妊娠、孕前疾病史均是高龄产妇不良妊娠结局的危险因素。 展开更多
关键词 不良妊娠结局 高龄产妇 影响因素
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静脉药物配置中心抗肿瘤药物使用的合理性分析 被引量:10
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作者 蔡莉 陈文静 冼宝珍 《中国当代医药》 2019年第16期205-208,共4页
目的通过对静脉药物配置中心(PIVAS)抗肿瘤药物处方中抗肿瘤药使用的合理性进行分析,为今后临床抗肿瘤药物的用药安全性和有效性提供参考依据。方法回顾性分析2014年8月~2017年8月我院PIVAS调配的2000组抗肿瘤药物处方,依据各类抗肿瘤... 目的通过对静脉药物配置中心(PIVAS)抗肿瘤药物处方中抗肿瘤药使用的合理性进行分析,为今后临床抗肿瘤药物的用药安全性和有效性提供参考依据。方法回顾性分析2014年8月~2017年8月我院PIVAS调配的2000组抗肿瘤药物处方,依据各类抗肿瘤药物说明书,参考相关药物使用标准(如药典、新编药物学、中国国家处方集、临床静脉用药调配与使用指南等),以及国家食品药品监督管理总局(CFDA)和美国FDA发布的相关警告等,统计处方中溶剂的用量和选择是否合理,抗肿瘤药物的给药途径、剂量、给药顺序及其他不合理用药情况;统计常见抗肿瘤药物的溶媒、浓度、输注时间的选择;统计抗肿瘤药物联合用药的给药顺序。结果 2000组处方中共有127组处方不合格,所占比例为6.35%,其中溶剂不合理占70.08%(89/127),表现为用量不当和选择不当;抗肿瘤药不合理占22.05%(28/127),包括给药途径不合理、剂量不合理及给药顺序不合理;其他不合理占7.09%(9/127)。不同抗肿瘤药所用溶剂、药液稳定性存在差异,因此临床输注时间、注意事项不同。在临床抗肿瘤药物联合应用时有一定的给药顺序,若用药顺序错误会影响药物的抗肿瘤效果或引发严重的不良反应。结论PIVAS抗肿瘤药物的使用存在处方不合理的问题,主要为溶剂用量不当、选择不当、抗肿瘤药给药途径不合理、剂量不合理、给药顺序不合理等,医院需要加强对上述问题的审核,保证抗肿瘤药物的质量和合理使用。 展开更多
关键词 抗肿瘤药 处方 静脉药物配置中心 输液
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某车型增压器进油管漏油问题分析及整改
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作者 殷怀彪 唐宗春 +4 位作者 席洪亮 赵波 线宝来 夏朝辉 王相凯 《内燃机与配件》 2024年第9期58-60,共3页
增压器进油管组件聚四氟乙烯(以下简称PTFE)软管在使用过程中发生泄露,采用扫描电镜发现断口纤维有粘连未完全断开,从软管内部观察断口附近有未完全裂开的伤口,对渗漏软管断口及刀切断口、烧伤断口、爆破断口等软管断口进行对比观察与分... 增压器进油管组件聚四氟乙烯(以下简称PTFE)软管在使用过程中发生泄露,采用扫描电镜发现断口纤维有粘连未完全断开,从软管内部观察断口附近有未完全裂开的伤口,对渗漏软管断口及刀切断口、烧伤断口、爆破断口等软管断口进行对比观察与分析,并对PTFE软管的成型烧结、软管切割、编织增强、组件扣压、总成装配、试验验证进行全过程排查,结果表明:PTFE软管是在安装过程中受扭曲应力,在发动机运行过程中振动和内部油压作用下,沿初始应力方向产生从内到外的横向撕裂口,最终导致漏油失效。 展开更多
关键词 增压器进油管组件 聚四氟乙烯 泄露
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人工收薹原理下蒜薹收获机的设计
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作者 杨静 张少强 +1 位作者 马兆毅 鲜宝刚 《机械研究与应用》 2024年第4期70-74,共5页
首先,以天水地区种植品种白蒜、红蒜为研究对象,基于人工抽薹原理,实施了夹薹压缩实验、抽薹拉伸试验。试验表明:白蒜蒜薹茎秆粗壮,其抗压应力较红蒜蒜薹大11%左右,抽拔力较红蒜蒜薹大9.5%左右;两个品种力学性能的不同归结于微观结构不... 首先,以天水地区种植品种白蒜、红蒜为研究对象,基于人工抽薹原理,实施了夹薹压缩实验、抽薹拉伸试验。试验表明:白蒜蒜薹茎秆粗壮,其抗压应力较红蒜蒜薹大11%左右,抽拔力较红蒜蒜薹大9.5%左右;两个品种力学性能的不同归结于微观结构不同。其次,建立了蒜薹收获机虚拟样机模型,并对抽薹过程进行了运动学分析,得出断薹率最小时机器前进速度与滚筒速度应满足的关系。在此基础上,设计了机械手的安装位置。最后,对夹薹过程进行仿真分析,得出蒜薹夹断时两夹薹轮的间隙为33.3 mm。研究结果为蒜薹收获机的结构设计提供理论依据。 展开更多
关键词 蒜薹 力学性能 运动特性 仿真分析
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基于“以广南者为佳”的广西铁皮石斛HPLC特征图谱研究 被引量:2
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作者 周春花 李运容 +3 位作者 胡东南 韦柱杨 杨永军 魏刚 《广东药科大学学报》 CAS 2018年第3期277-281,共5页
目的探讨"以广南者为佳"的广西铁皮石斛种源的主要来源,建立广西铁皮石斛HPLC特征图谱分析方法。方法采用Agilent ZORBAX SB C_(18)色谱柱(250 mm×4.6 mm,5μm);流动相为乙腈-10 mmol/L乙酸铵溶液(梯度洗脱);检测波长为3... 目的探讨"以广南者为佳"的广西铁皮石斛种源的主要来源,建立广西铁皮石斛HPLC特征图谱分析方法。方法采用Agilent ZORBAX SB C_(18)色谱柱(250 mm×4.6 mm,5μm);流动相为乙腈-10 mmol/L乙酸铵溶液(梯度洗脱);检测波长为340 nm;柱温为35℃;流速为1.0 mL/min。结果 12批广西铁皮石斛可分为2类,其中第Ⅰ类10批样品(产于广西丹霞地貌),标示出10个共有峰,相似度为0.856~0.970;第Ⅱ类2批(产于石灰岩地貌),共标示出9个共有峰,此2批石斛与第Ⅰ类共有模式的相似度分别为0.422、0.332。在选取的保留时间范围内,对照药材、福建丹霞种、浙江种、云南种与广西种第Ⅰ类铁皮石斛共有模式比较,相似度分别为0.575、0.158、0.397、0.757。结论广西容县、桂平等广西丹霞地貌原生的铁皮兰为"以广南者为佳"之广西铁皮石斛的代表性承载主体,且与云南广南等地的种源相似度较高,但与广东、福建等地丹霞地貌种、浙江本地种存在一定差异。建议《中国药典》采用的铁皮石斛对照药材应充分考虑这种不同道地种源之间的差异。 展开更多
关键词 广西铁皮石斛 铁皮兰 黄酮类化合物 特征图谱
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关于汽油机冷却系统存气问题分析及整改 被引量:1
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作者 殷怀彪 屈佳闻 +4 位作者 线宝来 何利 侯丽 王尧 张山峰 《内燃机与配件》 2021年第15期118-119,共2页
本文对汽车发动机存气导致的暖风水温上升慢问题进行分析及整改,在对发动机和整车更改较小的情况下,解决了存气和暖风水温上升慢问题。
关键词 发动机 冷却系统 暖机时间
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仿贝壳结构壳聚糖/绢云母复合薄膜的制备和性能 被引量:2
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作者 谭肃 张献 +4 位作者 包超 丁欣 胡坤 郑康 田兴友 《材料研究学报》 EI CAS CSCD 北大核心 2016年第10期763-766,共4页
采用物理共混的简易方法制备了壳聚糖/绢云母复合薄膜。场发射扫描电镜观测的结果表明,这种薄膜具有明显的取向"砖-泥"仿贝壳结构。这种独特仿生结构的形成显著地提高了壳聚糖复合薄膜的力学性能(拉伸强度和断裂伸长率),并且... 采用物理共混的简易方法制备了壳聚糖/绢云母复合薄膜。场发射扫描电镜观测的结果表明,这种薄膜具有明显的取向"砖-泥"仿贝壳结构。这种独特仿生结构的形成显著地提高了壳聚糖复合薄膜的力学性能(拉伸强度和断裂伸长率),并且保持了优异的柔软弯曲性能。同时,这种复合薄膜具有良好的透明性和电绝缘性能。 展开更多
关键词 无机非金属材料 仿生结构 复合薄膜 物理共混 绢云母 壳聚糖
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Fractional Flow Reserve Guided Percutaneous Coronary ntervention Improves Clinical Outcome with Reduced Cost in Contemporary Clinical Practice 被引量:19
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作者 Po Hu Meng-Yao Tang +6 位作者 Wen-Chao Song Jun Jiang Yong Sun xian-bao Liu Chang-Ling Li Xin-Yang Hu Jian-An Wang 《Chinese Medical Journal》 SCIE CAS CSCD 2015年第15期2000-2005,共6页
Background:Fractional flow reserve (FFR) is currently considered as the gold standard for evaluating the functional significance of coronary stenosis.However,its potential benefits in real-world practice remain unk... Background:Fractional flow reserve (FFR) is currently considered as the gold standard for evaluating the functional significance of coronary stenosis.However,its potential benefits in real-world practice remain unknown in China.This study aimed to test the hypothesis that the use of FFR is associated with improved outcome and reduced cost in Chinese real-world clinical practice.Methods:A retrospective cohort study was carried out using the database of Second Affiliated Hospital of Zhejiang University,a tertiary and high-volume center in China.Clinical events were compared using the Cox proportional hazards model during a median follow-up of 13 months.Results:The study cohort consisted of 366 consecutive patients referred for coronary revascularization with adjunct FFR and 366 matched controls,from 2010 to 2014.Major adverse cardiac events (MACEs) (death,myocardial infarction,repeated revascularization,or hospitalization for angina) at 4 years were found in 12.0% ofangiography-guided patients and 4.9% in the FFR-guided group (P 〈 0.001).The mean number of implanted stents was significantly lower in FFR treated subjects (0.52 ± 0.82 stents) compared with the angiography-guided group (0.93 ± 0.96 stents) (P 〈 0.001).No difference in overall costs at initial hospitalization was observed between angiography-guided percutaneous coronary intervention (PCI) compared with FFR-guided PCI (RMB 33,000 Yuan,range:RMB 7393-44,700 Yuan) versus RMB 21,200 Yuan (RMB 19,100-47,100 Yuan) (P =0.54).However,costs for MACEs during follow-up were significantly reduced in the FFR-guided arm (P 〈 0.001).Conclusions:In the contemporary clinical practice,FFR-guided PCI is associated with decreased use of stents,improved clinical outcome,and reduced costs,compared with angiography-guided PCI. 展开更多
关键词 Costs and Cost Analysis Fractional Flow Reserve Myocardial Percutaneous Coronary Intervention PROGNOSIS
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Complex coronary lesions and rotational atherectomy:one hospital's experience 被引量:13
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作者 Jun JIANG Yong SUN +5 位作者 Mei-xiang xianG Liang DONG xian-bao LIU Xin-yang HU Yan FENG Jian-an WANG 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2012年第8期645-651,共7页
Objective:To evaluate the safety and effectiveness of rotational atherectomy followed by drug eluting stent (DES) implantation in patients with complex coronary lesions. Methods:From August 2006 to August 2012, 253 co... Objective:To evaluate the safety and effectiveness of rotational atherectomy followed by drug eluting stent (DES) implantation in patients with complex coronary lesions. Methods:From August 2006 to August 2012, 253 consecutive patients with 289 lesions and who underwent rotational atherectomy in our center were enrolled in this study. Results:The overall procedure success rate was 98% with the cost of two (0.8%) coronary perforations, three (1.2%) dissections, five (2.0%) slow flows or no flows, three (1.2%) peri-procedure myocardial infarctions, and two (0.8%) in hospital deaths. During follow-up (mean three years), one (0.4%) patient died, two (0.8%) patients had acute myocardial infarction, 14 (5.5%) had restenosis, and target lesion revascularization occurred in eight patients (3.2%). Conclusions:Rotational atherectomy followed by DES implantation is a safe and effective technique for patients with complex coronary lesions, especially calcified and non-dilatable lesions. 展开更多
关键词 Complex coronary lesions Calcified coronary lesions Rotational atherectomy Drug eluting stents
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Heat shock protein 90 protects rat mesenchymal stem cells against hypoxia and serum deprivation-induced apoptosis via the PI3K/Akt and ERK1/2 pathways 被引量:12
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作者 Feng GAO Xin-yang HU +6 位作者 Xiao-jie XIE Qi-yuan XU Ya-ping WANG xian-bao LIU Mei-xiang xianG Yong SUN Jian-an WANG 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2010年第8期608-617,共10页
Mesenchymal stem cell (MSC) transplantation has shown a therapeutic potential to repair the ischemic and infracted myocardium, but the effects are limited by the apoptosis and loss of donor cells in host cardiac mic... Mesenchymal stem cell (MSC) transplantation has shown a therapeutic potential to repair the ischemic and infracted myocardium, but the effects are limited by the apoptosis and loss of donor cells in host cardiac microenvironment. The aim of this study is to explore the cytoprotection of heat shock protein 90 (Hsp90) against hypoxia and serum deprivation-induced apoptosis and the possible mechanisms in rat MSCs. Cell viability was determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Apoptosis was assessed by Hoechst 33258 nuclear staining and flow cytometric analysis with annexin V/PI staining. The gene expression of Toll-like receptor-4 (TLR-4) and V-erb-b2 erythroblastic leukemia viral oncogene homolog 2 (ErbB2) was detected by real-time poly- merase chain reaction (PCR). The protein levels of cleaved caspase-3, Bcl-2, Bcl-xL, Bax, totaI-ERK, phospho-ERK, totaI-Akt, phospho-Akt, and Hsp90 were detected by Western blot. The production of nitric oxide was measured by spectrophotometric assay. Hsp90 improves MSC viability and protects MSCs against apoptosis induced by serum deprivation and hypoxia. The protective role of Hsp90 not only elevates Bcl-2/Bax and Bcl-xL/Bax expression and attenuates cleaved caspase-3 expression via down-regulating membrane TLR-4 and ErbB2 receptors and then ac- tivating their downstream PI3K/Akt and ERK1/2 pathways, but also enhances the paracrine effect of MSCs. These findings demonstrated a novel and effective treatment strategy against MSC apoptosis in cell transplantation. 展开更多
关键词 Heat shock protein Apoptosis Stem cell HYPOXIA Phosphoinositide-3-kinase/protein kinase B (PI3K/Akt) Extracellular-signal-regulate kinase (ERK)
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Evaluation of the safety and efficacy of transcatheter aortic valve implantation in patients with a severe stenotic bicuspid aortic valve in a Chinese population 被引量:11
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作者 xian-bao LIU Ju-bo JIANG +11 位作者 Qi-jing ZHOU Zhao-xia PU Wei HE Ai-qiang DONG Yan FENG Jun JIANG Yong SUN Mei-xiang xianG Yu-xin HE You-qi FAN Liang DONG Jian-an WANG 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2015年第3期208-214,共7页
Objective: The purpose of this study is to evaluate the safety and efficacy of transcatheter aortic valve implantation (TAVI) in patients with a severe stenotic bicuspid aortic valve (BAV) in a Chinese population... Objective: The purpose of this study is to evaluate the safety and efficacy of transcatheter aortic valve implantation (TAVI) in patients with a severe stenotic bicuspid aortic valve (BAV) in a Chinese population. While several groups have reported the feasibility, efficacy, and safety of TAVI for patients with a BAV, worldwide experience of the technique is still limited, especially in China. Methods: From March 2013 to November 2014, high surgical risk or inoperable patients with symptomatic severe aortic stenosis (AS) who had undergone TAVI at our institution were selected for inclusion in our study. Results were compared between a BAV group and a tricuspid aortic valve (TAV) group. Results: Forty patients were included in this study, 15 (37.5%) of whom were identified as having a BAV. In the BAV group, the aortic valve area was smaller ((0.47±0.13) vs. (0.59±0.14) cm2), the ascending aortic diameter was larger ((40.4±4.4) vs. (36.4±4.3) mm), and the concomitant aortic regurgitation was lower. No significant differences were found between the groups in the other baseline characteristics. No differences were observed either in the choice of access or valve size. The procedural success achieved in this study was 100%. There were no differences between groups in device success (86.7% vs. 88.0%), 30-d mortality (6.7% vs. 8.0%), or 30-d combined end point (13.3% vs. 12.0%). The incidences of new pacemaker implantation, paravalvular regurgitation and other complications, recovery of left ventricle ejection fraction and heart function were similar in both groups. Conclusions: Patients with a severely stenotic BAV can be treated with TAVI, and their condition after treatment should be similar to that of people with a TAV. 展开更多
关键词 Aortic valve stenosis Bicuspid aortic valve Transcatheter aortic valve implantation
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Post-dilatation improves stent apposition in patients with ST-segment elevation myocardial infarction receiving primary percutaneous intervention: A multicenter, randomized controlled trial using optical coherence tomography 被引量:8
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作者 Jun Jiang Nai-liang Tian +8 位作者 Han-bin Cui Chang-ling Li xian-bao Liu Liang Dong Yong Sun Xiao-min Chen Shao-liang Chen Bo Xu Jian-an Wang 《World Journal of Emergency Medicine》 SCIE CAS CSCD 2020年第2期87-92,共6页
BACKGROUND: Stent failure is more likely in the lipid rich and thrombus laden culprit lesions underlying ST-segment elevation myocardial infarction(STEMI).This study assessed the effectiveness of post-dilatation in pr... BACKGROUND: Stent failure is more likely in the lipid rich and thrombus laden culprit lesions underlying ST-segment elevation myocardial infarction(STEMI).This study assessed the effectiveness of post-dilatation in primary percutaneous coronary intervention(pPCI) for acute STEMI.METHODS: The multi-center POST-STEMI trial enrolled 41 consecutive STEMI patients with symptom onset <12 hours undergoing manual thrombus aspiration and Promus Element stent implantation.Patients were randomly assigned to control group(n=20) or post-dilatation group(n=21) in which a non-compliant balloon was inflated to >16 atm pressure.Strut apposition and coverage were evaluated by optical coherence tomography(OCT) after intracoronary verapamil administration via thrombus aspiration catheter, post pPCI and at 7-month follow-up.The primary endpoint was rate of incomplete strut apposition(ISA) at 7 months after pPCI.RESULTS: There were similar baseline characteristics except for stent length(21.9 [SD 6.5] mm vs.26.0 [SD 5.8] mm, respectively, P=0.03).In post-dilatation vs.control group, ISA rate was lower(2.5% vs.4.5%, P=0.04) immediately after pPCI without affecting final TIMI flow 3 rate(95.2% vs.95.0%, P>0.05) or corrected TIMI frame counts(22.6±9.4 vs.22.0±9.7, P>0.05); and at 7-month follow-up(0.7% vs.1.8%, P<0.0001), the primary study endpoint, with similar strut coverage(98.5% vs.98.4%, P=0.63) and 1-year rate of major adverse cardiovascular events(MACE).CONCLUSION: In STEMI patients, post-dilatation after stent implantation and thrombus aspiration improved strut apposition up to 7 months without affecting coronary blood flow or 1-year MACE rate.Larger and longer term studies are warranted to further assess safety(Clinical Trials.gov identifier: NCT02121223). 展开更多
关键词 ST-segment elevation myocardial infarction Post-dilatation Incomplete strut apposition Optical coherence tomography
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Activation of Akt and cardioprotection against reperfusion injury are maximal with only five minutes of sevoflurane postconditioning in isolated rat hearts 被引量:8
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作者 Yuan-yuan YAO Man-hua ZHU +9 位作者 Feng-jiang ZHANG Chuan-yun WEN Lei-lei MA Wen-na WANG Can-can WANG xian-bao LIU Li-na YU Ling-bo QIAN Jian-an WANG Min YAN 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2013年第6期511-517,共7页
It had been proved that administration of sevoflurane for the first two minutes of reperfusion effectively protects the heart against reperfusion injury in rats in vivo.Our aim was to investigate the duration of effec... It had been proved that administration of sevoflurane for the first two minutes of reperfusion effectively protects the heart against reperfusion injury in rats in vivo.Our aim was to investigate the duration of effective sevoflurane administration and its underlying mechanism in isolated rat hearts exposed to global ischemia/reperfusion(I/R) injury.Adult male Sprague-Dawley rats were randomly divided into six groups(n=12):a sham-operation group,an I/R group,and four sevoflurane postconditioning groups(S2,S5,S10,and S15).In the S2,S5,S10,and S15 groups,the duration times of sevoflurane administration were 2,5,10,and 15 min after the onset of reperfusion,respectively.The isolated rat hearts were mounted on the Langendorff system,and after a period of equilibrium were subjected to 40 min global ischemia and 120 min reperfusion.Left ventricular(LV) hemodynamic parameters were monitored throughout each experiment and the data at 30 min of equilibrium and 30,60,90,and 120 min of reperfusion were analyzed.Myocardial infarct size at the end of reperfusion(n=7 in each group) and the expression of myocardial phosphorylated Akt(p-Akt) after 15-min reperfusion were determined in a duplicate set of six groups of rat hearts(n=5 in each group).Compared with the I/R group,the S5,S10,and S15 groups had significantly improved left ventricular end-diastolic pressure(LVEDP),left ventricular developed pressure(LVDP),and the maximal rate of rise or fall of the LV pressure(±dP/dtmax),and decreased myocardial infarct size(P<0.05),but not the S2 group.After 15 min of reperfusion,the expression of p-Akt was markedly up-regulated in the S5,S10,and S15 groups compared with that in the I/R group(P<0.05),but not in the S2 group.Sevoflurane postconditioning for 5 min was sufficient to activate Akt and exert maximal cardioprotection against I/R injury in isolated rat hearts. 展开更多
关键词 Sevoflurane postconditioning Ischemia/reperfusion(I/R) injury CARDIOPROTECTION Duration of administration AKT
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Ascending aortic dilatation rate after transcatheter aortic valve replacement in patients with bicuspid and tricuspid aortic stenosis: A multidetector computed tomography follow-up study 被引量:8
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作者 Yu-xin He Jia-qi Fan +6 位作者 Qi-feng Zhu Qi-jing Zhou Ju-bo Jiang Li-han Wang Stella Ng xian-bao Liu Jian-an Wang 《World Journal of Emergency Medicine》 SCIE CAS CSCD 2019年第4期197-204,共8页
BACKGROUND: Current data is lacking about the progression of ascending aortic dilatation after transcatheter aortic valve replacement(TAVR) in aortic stenosis(AS) patients with bicuspid aortic valve(BAV) and tricuspid... BACKGROUND: Current data is lacking about the progression of ascending aortic dilatation after transcatheter aortic valve replacement(TAVR) in aortic stenosis(AS) patients with bicuspid aortic valve(BAV) and tricuspid aortic valve(TAV). This study aims to assess the ascending aortic dilatation rate(mm/year) after TAVR in patients with BAV versus TAV using a multidetector computed tomography(MDCT) fol ow-up and to determine the predictors of ascending aortic dilatation rate.METHODS: Severe AS patients undergoing TAVR from March 2013 to March 2018 at our center with MDCT follow-ups were included. BAV and TAV were identified using baseline MDCT. Baseline and follow-up MDCT images were analyzed,and the diameters of ascending aorta were measured. Study end point is ascending aortic dilatation rate(mm/year). Furthermore,factors predicting ascending aortic dilatation rate were also investigated.RESULTS: Two hundred and eight patients were included,comprised of 86 BAV and 122 TAV patients. Five,4,3,2,and 1-year MDCT follow-ups were achieved in 7,9,30,46,and 116 patients. The ascending aortic diameter was significantly increased after TAVR in both BAV group(43.7±4.4 mm vs. 44.0±4.5 mm;P<0.001) and TAV group(39.1±4.8 mm vs. 39.7±5.1 mm;P<0.001). However,no difference of ascending aortic dilatation rate was found between BAV and TAV group(0.2±0.8 mm/year vs. 0.3±0.8 mm/year,P=0.592). Multivariate linear regression revealed paravalvular leakage(PVL) grade was independently associated with ascending aortic dilatation rate in the whole population and BAV group,but not TAV group. No aortic events occurred during follow-ups.CONCLUSION: Ascending aortic size continues to grow after TAVR in BAV patients,but the dilatation rate is mild and comparable to that of TAV patients. PVL grade is associated with ascending aortic dilatation rate in BAV patients post-TAVR. 展开更多
关键词 TRANSCATHETER AORTIC VALVE replacement AORTIC DILATATION BICUSPID AORTIC VALVE
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Accidental placement of venous return catheter in the superior vena cava during venovenous extracorporeal membrane oxygenation for severe pneumonia: A case report
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作者 Xiao-Qin Song Yun-Long Jiang +3 位作者 xian-bao Zou Shi-Chao Chen Ai-Jun Qu Ling-Ling Guo 《World Journal of Clinical Cases》 SCIE 2024年第4期782-786,共5页
BACKGROUND Venovenous extracorporeal membrane oxygenation(V-V ECMO)has become an important treatment for severe pneumonia,but there are various complications during the treatment.This article describes a case with sev... BACKGROUND Venovenous extracorporeal membrane oxygenation(V-V ECMO)has become an important treatment for severe pneumonia,but there are various complications during the treatment.This article describes a case with severe pneumonia success-fully treated by V-V ECMO,but during treatment,the retrovenous catheter,which was supposed to be in the right internal vein,entered the superior vena cava directly in the mediastinum.The ECMO was safely withdrawn after multidiscip-linary consultation.Our experience with this case is expected to provide a reference for colleagues who will encounter similar situations.CASE SUMMARY A 64-year-old man had severe pulmonary infection and respiratory failure.He was admitted to our hospital and was given ventilation support(fraction of inspired oxygen 100%).The respiratory failure was not improved and he was treated by V-V ECMO,during which the venous return catheter,which was supposed to be in the right internal vein,entered the superior vena cava directly in the mediastinum.There was a risk of massive mediastinal bleeding if the catheter was removed directly when the ECMO was withdrawn.Finally,the patient underwent vena cava angiography+balloon attachment+ECMO with-drawal in the operating room(prepared for conversion to thoracotomy for vascular exploration and repair at any time during surgery)after multidiscip-linary consultation.ECMO was safely withdrawn,and the patient recovered and was discharged.CONCLUSION Patients may have different vascular conditions.Multidisciplinary cooperation can ensure patient safety.Our experience will provide a reference for similar cases. 展开更多
关键词 Severe pneumonia Extracorporeal membrane oxygenation Complications Superior vena cava Multidisciplinary consultation Case report
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