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Evaluation of the traditional Chinese medicine Shensongyangxin capsule on treating premature ventricular contractions: a randomized, double-blind, controlled multicenter trial 被引量:73
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作者 ZOU Jian-gang ZHANG Jian +1 位作者 JIA Zhen-hua CAO Ke-jiang 《Chinese Medical Journal》 SCIE CAS CSCD 2011年第1期76-83,共8页
Background Premature ventricular contraction (PVC) is one of the most common kinds of arrhythmias for which the treatment falls into dilemma. Previous clinical application showed that the traditional Chinese Medicin... Background Premature ventricular contraction (PVC) is one of the most common kinds of arrhythmias for which the treatment falls into dilemma. Previous clinical application showed that the traditional Chinese Medicine Shensongyangxin (SSYX) capsule is efficacious for the treatment of PVCs. This randomized clinical trial aimed to further evaluate the efficacy and safety of SSYX capsule on treating PVC. Methods The subjects who had frequent PVCs with or without organic heart disease and normal cardiac function were enrolled in the study. The primary endpoint was the change of PVC numbers after eight-week medication with SSYX capsule. The secondary endpoints included change of clinical symptoms related to PVCs and the safety evaluation of SSYX capsule. Totally 188 PVC patients were randomly enrolled in the non-organic heart disease PVCs trial and orally took either $SYX capsules or analogues (three times per day, 4 capsules one time). A total of 671 PVCs patients were randomly enrolled in the organic heart disease PVCs trial, and orally took either SSYX capsules (three times per day, 4 capsules one time) or mexiletine tablet (three times per day, 150 mg one time). The PVCs were monitored and calculated with 24-hour Holter electrocardiogram. Routine blood, liver and kidney function were tested before and after medication with SSYX capsule. Results SSYX capsules significantly decreased the PVCs numbers and alleviated the related symptoms in patients with or without organic heart disease. In non-organic heart disease group, SSYX capsules and the placebos decreased the PVCs from 12561.34±9777.93 to 4806.87±6507.17, and 12 605.69±8736.34 to 10364.94±9903.41, respectively. The total effective rate was 74.2% and 28.9% in SSYX and placebo groups (P〈0.001). In organic heart disease group, SSYX capsule and mexiletine decreased the PVCs from 8641.01±8923.57 to 3853.68±7096.42, 8621.61±8367.74 to 5648.29±8667.38, respectively, The total effective rate was 65.8% and 50.7% in SSYX and mexiletine g 展开更多
关键词 premature ventricular contraction Shensongyangxin capsule randomized controlled trial
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前置胎盘阴道流血与宫缩的关系81例分析 被引量:54
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作者 曾蔚越 刘丽红 罗艳 《实用妇产科杂志》 CAS CSCD 北大核心 2003年第1期35-36,共2页
目的 :评价前置胎盘阴道流血与子宫收缩的关系 ,以及抑制子宫收缩在前置胎盘期待疗法中的作用。方法 :对 81例入院诊断为前置胎盘或胎盘前置状态的病例监测其宫缩、阴道流血情况 ,给予硫酸镁加 (或 )舒喘灵或羟苄羟麻黄碱 (安宝 )抑制... 目的 :评价前置胎盘阴道流血与子宫收缩的关系 ,以及抑制子宫收缩在前置胎盘期待疗法中的作用。方法 :对 81例入院诊断为前置胎盘或胎盘前置状态的病例监测其宫缩、阴道流血情况 ,给予硫酸镁加 (或 )舒喘灵或羟苄羟麻黄碱 (安宝 )抑制宫缩。结果 :前置胎盘阴道流血者 70 .80 %伴有不同程度宫缩 ,抑制宫缩治疗前置胎盘阴道流血有效率达 96 .5 % ,平均延长孕周 2 6 8天 ,新生儿平均体重 2 977 4g。结论 :前置胎盘或胎盘前置状态阴道流血与宫缩关系密切。抑制宫缩对治疗前置胎盘阴道流血有重要意义 。 展开更多
关键词 前置胎盘 阴道流血 子宫收缩 期待疗法 诊断
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胃动素和胃泌素引起大鼠胃窦平滑肌细胞收缩的信号转导通路 被引量:31
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作者 王玲 周吕 《生理学报》 CAS CSCD 北大核心 2000年第4期272-276,共5页
应用大鼠游离胃窦平滑肌细胞 ,观察胃动素和胃泌素对胃窦平滑肌细胞收缩作用的胞内信号转导通路。结果显示 :(1)胃动素和胃泌素对胃窦平滑肌细胞均有收缩作用 ;(2 )Gαi 3 抗体可抑制胃动素和胃泌素加强胃窦平滑肌细胞的收缩 ,胃动素、... 应用大鼠游离胃窦平滑肌细胞 ,观察胃动素和胃泌素对胃窦平滑肌细胞收缩作用的胞内信号转导通路。结果显示 :(1)胃动素和胃泌素对胃窦平滑肌细胞均有收缩作用 ;(2 )Gαi 3 抗体可抑制胃动素和胃泌素加强胃窦平滑肌细胞的收缩 ,胃动素、胃泌素明显增加Gαi 3 抗体与 [35S]GTPγS的结合 ;(3)磷脂酶C抑制剂U 7312 2、三磷酸肌醇受体拮抗剂肝素可抑制胃动素和胃泌素引起的胃窦平滑肌细胞的收缩。结果表明 :胃动素和胃泌素通过兴奋与磷脂酶C耦联的Gi 蛋白 ,产生三磷酸肌醇 ,激发胃窦平滑肌细胞的收缩反应。 展开更多
关键词 胃动素 胃泌素 收缩 G蛋白 磷脂酶C
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艾叶油的呼吸系统药理研究Ⅰ,支气管扩张、镇咳和祛痰作用 被引量:44
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作者 谢强敏 卞如濂 +2 位作者 杨秋火 唐法娣 王砚 《中国现代应用药学》 CAS CSCD 1999年第4期16-19,共4页
目的 :探讨艾叶油的扩张气道平滑肌、镇咳、祛痰作用及机制。方法 :采用哮喘发作潜伏期、肺机械功能及离体气管平滑肌松弛试验 ,观察艾叶油的支气管扩张作用 ;用豚鼠枸橼酸引咳法和小鼠气道酚红排泄法观察艾叶油的镇咳祛痰作用。结果 :... 目的 :探讨艾叶油的扩张气道平滑肌、镇咳、祛痰作用及机制。方法 :采用哮喘发作潜伏期、肺机械功能及离体气管平滑肌松弛试验 ,观察艾叶油的支气管扩张作用 ;用豚鼠枸橼酸引咳法和小鼠气道酚红排泄法观察艾叶油的镇咳祛痰作用。结果 :艾叶油ig或气雾吸入对组胺和乙酰胆碱引起的豚鼠哮喘具有保护作用 ,明显延长哮喘潜伏期 ;并呈剂量依赖保护致敏豚鼠抗原攻击引起的呼吸频率、潮气量和气道流速改变 ;松弛静息豚鼠离体气管平滑肌 ;呈剂量依赖抑制枸橼酸引起的豚鼠咳嗽反应和促进小鼠气道酚红排泄。结论 :综上结果表明艾叶油具有支气管扩张、镇咳和祛痰作用 ,是一个从中药中提取的安全有效的支气管哮喘和慢性气管炎治疗药物。 展开更多
关键词 艾叶油 支气管扩张 镇咳 祛痰 中医药疗法
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Mesozoic contraction deformation in the Yanshan and northern Taihang mountains and its implications to the destruction of the North China Craton 被引量:43
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作者 ZHANG ChangHou LI ChengMing +5 位作者 DENG HongLing LIU Yang LIU Lei WEI Bo LI HanBin LIU Zi 《Science China Earth Sciences》 SCIE EI CAS 2011年第6期798-822,共25页
Mesozoic contraction deformation in the Yanshan and Taihang mountains is characterized by basement-involved thrust tectonics,basement-cored buckling anticlines and ductile thrust and nappe tectonics.Most of these defo... Mesozoic contraction deformation in the Yanshan and Taihang mountains is characterized by basement-involved thrust tectonics,basement-cored buckling anticlines and ductile thrust and nappe tectonics.Most of these deformations are orientated west-east,west-northwest and northeast to north-northeast.The contraction deformations began in the Permian,continued through the Triassic and Jurassic and terminated in the Early Cretaceous,and constitute an important part of the destruction of the North China Craton.It is estimated,from balanced cross-section reconstructions,that the north-south shortening of the central part of the Yanshan belt before 135 Ma was around 38%.The initial crust thickness,pre-dating the major contraction deformation in late Paleozoic and early Mesozoic,was estimated to be around 35 km based on paleogeographic characteristics.Assuming that the inferred depth of ductile thrusting deformation,20-25 km,was the crust thickness involved in the contraction deformation,and also assuming that the N-S contraction deformation was accommodated by vertical crust thickening,the thickness of the crust after the contraction deformation was expected to be around 47-50 km.This was the approximate crust thickness required for the eclogitization of the lower crust for delamination.The gravity potential accumulated by the isostatic uplift of the thickened crust,together with the decrease in crustal strength caused by the coeval magmatisms associated with the contraction deformation,led to the subsequent extensional collapse of the middle and upper crust although the regional stress regime associated with the plate interactions remained constant.It is inferred that the Mesozoic contraction deformations in the Yanshan and Taihang mountains were not only a significant tectonic process contributing to the destruction of the craton in middle and upper crust but also stimulated delamination at a deep level and the extension of the shallow crust.In other words,both the suspected delamination of the lower crust and upper ma 展开更多
关键词 North China Craton Yanshan belt Taihang Mountain contraction deformation gravitational collapse
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胃动素对大鼠胃平滑肌细胞收缩活动的作用 被引量:30
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作者 周吕 王新 《生理学报》 CAS CSCD 北大核心 1996年第2期165-172,共8页
本研究用大鼠游离的胃平滑肌细胞,观察胃动素对胃平滑肌细胞的收缩作用。结果表明:(1)胃动素明显增强单个胃平滑肌细胞收缩活动,在生理剂量10(-11)─10(-10)mol范围内,呈剂量依赖性。(2)不同胃分区平滑肌细... 本研究用大鼠游离的胃平滑肌细胞,观察胃动素对胃平滑肌细胞的收缩作用。结果表明:(1)胃动素明显增强单个胃平滑肌细胞收缩活动,在生理剂量10(-11)─10(-10)mol范围内,呈剂量依赖性。(2)不同胃分区平滑肌细胞对冒动素兴奋反应不同,胃动素对胃窦平滑肌细胞收缩强度大于胃体和幽门。(3)给予抗胃动素血清可以完全取消胃动素对胃肌细胞的收缩反应,而阿托品、TTX、甲氰米胍、loxiglumide均不影响胃动素的作用。(4)给予胞内钙释放阻断剂TMB-8可抑制胃动素对目肌细胞的收缩作用。上述结果提示,胃动素对胃平滑肌细胞的直接作用是由胃动素受体所介导,且与胞内Ca(2+)释放起重要作用。 展开更多
关键词 胃动素 收缩 胃平滑肌细胞
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On the Existence of Positive Periodic Solutions for Neutral Functional Differential Equation with Multiple Deviating Arguments 被引量:36
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作者 Shi-pingLu Wei-gaoGe 《Acta Mathematicae Applicatae Sinica》 SCIE CSCD 2003年第4期631-640,共10页
By means of an abstract continuation theory for k-set contraction and continuation theorem of coincidence degree principle, some criteria are established for the existence of positive periodic solutions of following n... By means of an abstract continuation theory for k-set contraction and continuation theorem of coincidence degree principle, some criteria are established for the existence of positive periodic solutions of following neutral functional differential equation 展开更多
关键词 Positive periodic solution k-set contraction coincidence degree neutral functional differential equation
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陈皮、党参等中药对大鼠结肠肌条收缩活动的影响 被引量:20
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作者 刘克敬 谢冬萍 +3 位作者 李伟 瞿颂义 郑天珍 杨颖丽 《山东大学学报(医学版)》 CAS 2003年第1期34-35,38,共3页
目的:探讨陈皮、党参等八味中药对结肠运动的影响。方法:结肠肌条在盛有5mlKrebs液37℃并供给95%O2和5%CO2混合气体的灌流肌槽中孵育,记录肌条自发收缩活动。以肌条平均收缩幅度,静息张力和收缩频率为指标,观察各药对大鼠结肠自发收缩... 目的:探讨陈皮、党参等八味中药对结肠运动的影响。方法:结肠肌条在盛有5mlKrebs液37℃并供给95%O2和5%CO2混合气体的灌流肌槽中孵育,记录肌条自发收缩活动。以肌条平均收缩幅度,静息张力和收缩频率为指标,观察各药对大鼠结肠自发收缩活动的影响。结果:陈皮、党参、黄芪、白术、太子参、藿香、苍术和薤白均对大鼠结肠肌条收缩幅度有一定的影响(P<0.05)。结论:陈皮、党参、黄芪、白术、太子参、藿香、苍术和薤白可以调节结肠平滑肌的收缩活动。 展开更多
关键词 中草药 结肠 收缩 大鼠 近交系 平滑
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三元收缩段优化设计研究 被引量:34
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作者 张连河 范洁川 《空气动力学学报》 CSCD 北大核心 2003年第4期417-423,共7页
本文以某低速风洞收缩段为例,对收缩段设计方案的数值计算结果进行了综合分析。文中给出了数值计算结果、分析过程以及典型算例,并给出了该风洞收缩段最佳的气动设计方案,分析了几种常用收缩曲线的特点,同时给出了低速风洞收缩段气动设... 本文以某低速风洞收缩段为例,对收缩段设计方案的数值计算结果进行了综合分析。文中给出了数值计算结果、分析过程以及典型算例,并给出了该风洞收缩段最佳的气动设计方案,分析了几种常用收缩曲线的特点,同时给出了低速风洞收缩段气动设计的优化过程和可行的方法。结果表明,本文提出的优化设计方法是风洞三元收缩段气动设计较好的有效的气动设计手段。 展开更多
关键词 风洞试验 收缩段 优化设计 数值模拟 空气动力学实验
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血清饥饿可诱导人血管平滑肌细胞再分化 被引量:26
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作者 韩梅 温进坤 +1 位作者 郑斌 聂磊 《中国生物化学与分子生物学报》 CAS CSCD 北大核心 2003年第2期250-255,共6页
体外培养的分化型血管平滑肌细胞 (vascularsmoothmusclecells ,VSMC)以特异性标志基因表达、长梭形外观及对兴奋剂刺激产生收缩反应为其表型特征 .以血清饥饿法培养处于超汇合 (overconfluence)状态的人VSMC ,观察其分化型标志基因表... 体外培养的分化型血管平滑肌细胞 (vascularsmoothmusclecells ,VSMC)以特异性标志基因表达、长梭形外观及对兴奋剂刺激产生收缩反应为其表型特征 .以血清饥饿法培养处于超汇合 (overconfluence)状态的人VSMC ,观察其分化型标志基因表达活性及其与细胞形态特征和收缩反应性之间的关系 ,探讨细胞生存环境对VSMC基因表达及表型的影响 .研究显示 ,生长至超汇合的VSMC由含血清培养转为血清饥饿后 ,收缩蛋白如SMα肌动蛋白 (SMα actin)、SM2 2α、h1 calponin、肌球蛋白重链 (MHC)SM1和SM2亚型的表达活性明显上调 ,证实血清饥饿诱导的收缩蛋白基因表达和血清应答因子 (serumresponsefactor ,SRF)与CArG顺式元件结合活性的增强有关 .同时 ,血清饥饿还可激活参与VSMC分化调节的转录调控因子SmLIM、Gax和分化相关蛋白HRG 1基因的转录 .随着血清饥饿培养时间的延长 ,VSMC逐渐形成多层、束状、成极性排列的形式 ,对兴奋剂刺激产生的收缩反应明显增强 .结果表明 ,超汇合状态的去分化型VSMC脱离血清刺激后 。 展开更多
关键词 血管平滑肌细胞 再分化 表型转化 标志基因 细胞功能 血清饥饿培养 收缩蛋白 收缩调节蛋白 基因表达
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Contraction Integrated Semigroups and Their Applicationto Continuous-time Markov Chains 被引量:31
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作者 YangRongLI 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2003年第3期605-618,共14页
We introduce the notion of the contraction integrated semigroups and give the Lumber-Phillips characterization of the generator, and also the charaterazied generators of isometric integrated semigroups. For their appl... We introduce the notion of the contraction integrated semigroups and give the Lumber-Phillips characterization of the generator, and also the charaterazied generators of isometric integrated semigroups. For their application, a necessary and sufficient condition for q-matrices Q generating a contraction integrated semigroup is given, and a necessary and sufficient condition for a transition function to be a Feller-Reuter-Riley transition function is also given in terms of its q-matrix. 展开更多
关键词 Keywords Integrated semigroups contraction integrated semigroups Markov chains Transition functions q matrices Feller Reuter Riley transition functions
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枳实对大鼠结肠肌条运动的影响 被引量:14
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作者 谢冬萍 李伟 +5 位作者 瞿颂义 郑天珍 杨颖丽 丁永辉 魏玉玲 张孟业 《山东医科大学学报》 2001年第5期437-438,共2页
目的 :观察枳实对大鼠离体结肠肌条收缩活动的影响。方法 :结肠肌条在盛有 5mlKrebs液(37℃ )并供给 95 %O2 和 5 %CO2 混合气体的灌流肌槽中孵育 ,记录肌条的自发收缩活动。分别观察加入枳实、酚妥拉明、普萘洛尔或L NNA对肌条收缩活... 目的 :观察枳实对大鼠离体结肠肌条收缩活动的影响。方法 :结肠肌条在盛有 5mlKrebs液(37℃ )并供给 95 %O2 和 5 %CO2 混合气体的灌流肌槽中孵育 ,记录肌条的自发收缩活动。分别观察加入枳实、酚妥拉明、普萘洛尔或L NNA对肌条收缩活动的影响。结果 :枳实可显著减小结肠肌条的平均收缩幅度及频率。该作用可被酚妥拉明部分阻断 ,但不受普萘洛尔或L NNA的影响。结论 :枳实可抑制大鼠离体结肠肌条的收缩活动 ,该抑制作用部分与α受体有关。 展开更多
关键词 枳实 结肠 平滑肌 收缩 大鼠 近交系 结肠肌条运动
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胞内钙释放在胃泌素引起胃平滑肌细胞收缩中的作用 被引量:13
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作者 周吕 罗洁新 《生理学报》 CAS CSCD 北大核心 1997年第2期197-203,共7页
本研究用大鼠游离的胃平滑肌细胞,观察五肽胃泌素(G5)对胃平滑肌细胞的收编作用及胃泌索引起胃平滑肌细胞收缩时胞内游离钙释放作用。结果表明:(1)G5能够引起胃体、胃窦、幽门平滑肌细胞收缩,并对胃窦作用最强。在G54×10-8... 本研究用大鼠游离的胃平滑肌细胞,观察五肽胃泌素(G5)对胃平滑肌细胞的收编作用及胃泌索引起胃平滑肌细胞收缩时胞内游离钙释放作用。结果表明:(1)G5能够引起胃体、胃窦、幽门平滑肌细胞收缩,并对胃窦作用最强。在G54×10-8~16×10-8mol/L剂量范围内,呈剂量依赖性。(2)丙谷胺或抗胃泌素血清可以阻断G5对胃肌细胞的收缩反应,而阿托品则不影响G5的作用。(3)G5与乙酸胆碱对平滑肌细胞收缩有相加作用。(4)胞内钙释放阻断剂TMB-8可抑制G5对胃肌细胞的收缩作用。(5)G5作用于胃窦平滑肌细胞后胞内游离Ca2+显著上升。上述结果提示:胃泌素通过特异性受体引起胃平滑肌细胞收缩,其收缩作用通过胞内Ca2+释放介导。 展开更多
关键词 胃平滑肌细胞 胃泌素 收缩 游离钙
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Structural Association of Endoplasmic Reticulum with Other Membrane Systems in Populus deltoides Apical Bud Cells and Its Alterations During the Short Day_induced Dormancy 被引量:15
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作者 简令成 李积宏 +1 位作者 李本湘 陈辉煌 《Acta Botanica Sinica》 CSCD 2000年第8期803-810,共8页
Electron microscopic observations revealed that the tissues of poplar ( Populus deltoides Bartr. ex Marsh) apical bud cells, which were fixed by a modified procedure of potassium permanganate fixative, showed a di... Electron microscopic observations revealed that the tissues of poplar ( Populus deltoides Bartr. ex Marsh) apical bud cells, which were fixed by a modified procedure of potassium permanganate fixative, showed a distinct endomembrane organization, in particular, the structural associations of the endoplasmic reticulum (ER) with other membrane systems. The striking findings are that some ER elements were in connection with the nuclear envelopes of two adjacent cells through plasmodesmata, and many ER elements were also associated with mitochondria, plastids, Golgi bodies or the plasma membrane (PM), forming a bridge_like continuum among various endomembrane systems or between nucleus to nucleus. A great number of plasmodesmata existed between cells, indicating a perfectly integrated symplasmic structure in poplar apical bud meristem grown in a long day environment. During the short day_induced dormancy, ER contracted, leading to its disassociation between nuclei, and between the nucleus and organelles/plasmalemma in many cells. After dormancy broke and shoots growth resumed, contracted ER was no longer observed in the apical bud cells. The ER associations with other endomembrane systems and the intercellular communication channels were re_established similar to that of plants before dormancy induction. These observations suggest that ER may play an important role in linking_up between the nucleus and organelles, and between the nucleus and the nucleus (or cell_to_cell), and seemingly coordinating various physiological processes by the bridging_like associations. And the contraction of ER under short_day may result in the growth cessation and the development of dormancy in poplar. 展开更多
关键词 endoplasmic reticulum ER_bridge association endoplasmic reticulum contraction PLASMODESMA DORMANCY Populus deltoides
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秦岭岩群中两类斜长角闪岩的性质和时代及其地质意义 被引量:24
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作者 闫全人 王宗起 +4 位作者 闫臻 陈隽璐 向忠金 王涛 张宏远 《岩石学报》 SCIE EI CAS CSCD 北大核心 2009年第9期2177-2194,共18页
在北秦岭造山带核部秦岭岩群内发育两类不同产状的斜长角闪岩。一类与秦岭岩群中的大理岩紧密共生,呈规模较大的似层状或较小块体产于大理岩内,另一类则呈密集岩墙群型式侵入于秦岭岩群南段二云母石英片岩中。不同的产出状态表明两类斜... 在北秦岭造山带核部秦岭岩群内发育两类不同产状的斜长角闪岩。一类与秦岭岩群中的大理岩紧密共生,呈规模较大的似层状或较小块体产于大理岩内,另一类则呈密集岩墙群型式侵入于秦岭岩群南段二云母石英片岩中。不同的产出状态表明两类斜长角闪岩的成因和时代存在显著差异,也具有不同的地质构造意义。地球化学上,两类不同产状的斜长角闪岩的原岩皆为玄武岩质的。侵入秦岭岩群二云母石英片岩中的斜长角闪岩墙群形成于板内拉张环境,SHRIMP锆石U-Pb测年揭示该类斜长角闪岩形成于晚奥陶世(449±11Ma),Sr-Nd同位素特征显示其岩浆源区为亏损地幔源区,^(40)Ar/^(39)Ar热年代学研究显示该类斜长角闪岩的角闪岩相变质作用发生于石炭纪末期(301.3±6.4Ma)。地球化学和Sr-Nd同位素特征显示与秦岭岩群大理岩共生的似层状或块状斜长角闪岩的形成环境与侵入云母石英片岩中的斜长角闪岩墙群的存在显著差异,其形成于洋岛(OIB)或海山环境。^(40)Ar/^(39)Ar热年代学研究显示该类斜长角闪岩于晚二叠世(258.1±5.7Ma)发生了角闪岩相变质作用。不同性质、形成和变质时代、相似的变质作用等特点表明,秦岭岩群中的两类角闪岩分属不同性质的构造块体,秦岭岩群高级变地质地体可能是一个构造拼合地体。斜长角闪岩岩墙为晚奥陶世(449±11Ma)侵入秦岭岩群云英片岩中的基性岩墙群,是北秦岭晚加里东期后造山期热收缩而致的地壳伸展或岩圈拆离减薄的产物。与秦岭岩群大理岩共生的斜长角闪岩则可能是洋隆体的基性喷出岩+碳酸盐岩帽组合,是中二叠世(312~260Ma)期间构造移置而来的外来块体。 展开更多
关键词 秦岭岩群 斜长角闪岩 性质 时代 地质意义 two 角闪岩相变质作用 岩墙群 大理岩 SR-ND同位素 年代学研究 thermal contraction 显著差异 晚奥陶世 片岩 构造 地球化学 tectonic setting results 云母
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轨道交通预应力混凝土连续梁桥的徐变控制 被引量:15
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作者 凌知民 《桥梁建设》 EI CSCD 北大核心 2002年第3期25-28,共4页
采用按龄期调整有效模量的时变分析有限元法 ,对城市轨道交通预应力混凝土连续梁桥的收缩徐变变形进行理论计算 ,并与实测结果进行对比分析 ,得出了有意义的结论。
关键词 轨道交通 预应力混凝土连续梁桥 徐变控制 收缩徐变变形
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3'-大豆苷元磺酸钠对豚鼠离体右心房自律性及收缩特性的影响 被引量:22
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作者 曾靖 黄志华 +3 位作者 李良东 叶和杨 肖海 黄真 《时珍国医国药》 CAS CSCD 北大核心 2007年第7期1553-1554,共2页
目的研究3'-大豆苷元磺酸钠对豚鼠离体右心房自律性及收缩特性的影响,并探讨其作用机制。方法采用豚鼠离体右心房测定3'-大豆苷元磺酸钠对其自律性、收缩幅度、收缩速度、舒张速度的影响。结果3'-大豆苷元磺酸钠可降低豚鼠... 目的研究3'-大豆苷元磺酸钠对豚鼠离体右心房自律性及收缩特性的影响,并探讨其作用机制。方法采用豚鼠离体右心房测定3'-大豆苷元磺酸钠对其自律性、收缩幅度、收缩速度、舒张速度的影响。结果3'-大豆苷元磺酸钠可降低豚鼠离体右心房的自律性,明显降低豚鼠离体右心房的收缩幅度、收缩速度、舒张速度,且具有明显的剂量依赖性。结论3'-大豆苷元磺酸钠可抑制豚鼠离体右心房的自律性,明显降低豚鼠离体右心房的收缩幅度、收缩速度、舒张速度,且具有明显的剂量依赖性。其作用机制可能与阻断电压依赖性Ca2+通道及抑制肌浆网对Ca2+的释放有关。 展开更多
关键词 3'-大豆苷元磺酸钠 右心房 自律性 收缩特性
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Ge-Gen Decoction attenuates oxytocin-induced uterine contraction and writhing response: potential application in primary dysmenorrhea therapy 被引量:19
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作者 YANG Lu CHAI Cheng-Zhi +4 位作者 YUE Xin-Yi YAN Yan KOU Jun-Ping CAO Zheng-Yu YU Bo-Yang 《Chinese Journal of Natural Medicines》 SCIE CAS CSCD 2016年第2期124-132,共9页
The uterine tetanic contraction and uterine artery blood flow reduction are possible reasons for primary dysmenorrhea(PD). In the present study, we aimed to evaluate the uterine relaxant effect and the influence on ut... The uterine tetanic contraction and uterine artery blood flow reduction are possible reasons for primary dysmenorrhea(PD). In the present study, we aimed to evaluate the uterine relaxant effect and the influence on uterine artery blood velocity of Ge-Gen Decoction(GGD), a well-known Chinese herbal formula. In female ICR mice, uterine contraction was induced by oxytocin exposure following estradiol benzoate pretreatment, and the uterine artery blood velocity was detected by Doppler ultrasound. Histopathological examination of the uterine tissue samples were performed by H&E staining. Ex vivo studies demonstrated that oxytocin, posterior pituitary, or acetylcholine induced contractions in isolated mouse uterus. GGD inhibited both spontaneous and stimulated contractions. In vivo study demonstrated that GGD significantly reduced oxytocin-induced writhing responses with a maximal inhibition of 87%. Further study demonstrated that GGD normalized oxytocin-induced abnormalities of prostaglandins F_2 alpha(PGF_(2α)) and Ca^(2+) in mice. In addition, injection of oxytocin induced a decrease in uterine artery blood flow velocity. Pretreatment with GGD reversed the oxytocin response on blood flow velocity. Histopathological examination showed pretreatment with GGD alleviated inflammation and edema in the uterus when compared with the model group. Both ex vivo and in vivo results indicated that GGD possessed a significant spasmolytic effect on uterine tetanic contraction as well as improvement on uterine artery blood velocity which may involve PGF_(2α) and Ca^(2+) signaling, suggesting that GGD may have a clinic potential in PD therapy. 展开更多
关键词 Primary dysmenorrheal Spasmolytic and analgesic effect Uterine contraction Uterine artery blood flow Ge-Gen Decoction
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Seismic damage-cracking analysis of arch dams using different earthquake input mechanisms 被引量:19
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作者 JianWen Pan ChuHan Zhang +1 位作者 JinTing Wang YanJie Xu 《Science China(Technological Sciences)》 SCIE EI CAS 2009年第2期518-529,共12页
In this study, a nonlinear model is presented for analysis of damage-cracking behavior in arch dams during strong earthquakes using different seismic input mechanisms. The nonlinear system includes a plastic-damage mo... In this study, a nonlinear model is presented for analysis of damage-cracking behavior in arch dams during strong earthquakes using different seismic input mechanisms. The nonlinear system includes a plastic-damage model for cyclic loading of concrete considering strain softening and a contact boundary model of contraction joint opening. Two different earthquake input mechanisms are used for comparison, including massless foundation input model and viscous-spring boundary model considering radiation damping due to infinite canyon. The results demonstrate that effects of seismic input mechanism and radiation damping on nonlinear response and damage-cracking of the dam are significant. Compared with the results of using massless foundation input model, the damage-cracking region and contraction joint opening are substantially reduced when using viscous-spring boundary model to take into account radiation damping. However, if the damping ratio of the dam is artificially increased to about 10%―15% for massless foundation input model, the joint opening and damage-cracking of the dam are comparable to the results obtained from the viscous-spring boundary model. 展开更多
关键词 EARTHQUAKE input mechanism damage-cracking radiation DAMPING contraction JOINTS ARCH DAM
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泡沫混凝土的研究及常见问题分析与对策 被引量:19
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作者 郑健 《山西建筑》 2008年第32期166-167,共2页
介绍了泡沫混凝土的性能优点、发泡剂的研究与应用、生产工艺,提出了我国目前泡沫混凝土生产和使用过程中存在的问题,分析了问题的产生原因和施工操作上的影响因素,指出制备优质泡沫混凝土的可能途径。
关键词 泡沫混凝土 强度 收缩 影响因素 对策
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