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Notoginsenoside R<sub>1</sub>Attenuates Hypoxia and Hypercapnia-Induced Vasoconstriction <i>In Vitro</i>by Reducing the Expression of p38
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作者 Congcong Zhang Meiping Zhao +2 位作者 Mengxiao Zheng Longsheng Song Wantie Wang 《Journal of Biosciences and Medicines》 2017年第8期1-10,共10页
Notoginsenoside R1, the main active ingredient of Panax notoginseng saponins (PNS), has been proposed to play fatal roles in the development of hypoxic hypercapnia-induced pulmonary vasoconstriction (HHPV). Subsequent... Notoginsenoside R1, the main active ingredient of Panax notoginseng saponins (PNS), has been proposed to play fatal roles in the development of hypoxic hypercapnia-induced pulmonary vasoconstriction (HHPV). Subsequently, pulmonary arterial smooth muscle cells (PASMCs) lead to pulmonary vascular system remodeling and chronic pulmonary disease in the development of HHPV. Despite considerable studies have contributed to pulmonary disease, the mechanism of how Notoginsenoside R1 affects HHPV remains unclear. In this view, we will discuss the effect of notoginsenoside R1 by investigating the expression of p38 mitogen-activated protein kinase (p38 MAPK) signaling pathway in PASMCs under hypoxia and hypercapnia condition. The third order PASMCs of Sprague Dawley (SD) rats were cultured with various concentrations (8, 40, 100 mg/L, respectively) of Notoginsenoside R1. Our data showed that the protein and mRNA expression levels of p-38 MAPK were higher in hypoxic hypercapnia group compared with hypoxic DMSO and normoxia control groups (p 1 treatment groups, the level of p-p38 MAPK protein and p38 MAPK mRNA were significantly decreased with different degrees (p 1 treatment may contribute to attenuate HHPV via decreasing the protein and mRNA expression levels of p-38 MAPK. 展开更多
关键词 Hypoxic HYPErCAPNIA P38 MAPK notoginsenoside r1 Pulmonary Arterial Smooth Muscle Cells
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ARMS实时PCR基因分型特异性的研究 被引量:2
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作者 郑薇薇 梁基选 李庆阁 《厦门大学学报(自然科学版)》 CAS CSCD 北大核心 2005年第B06期135-139,共5页
以原癌基因Kras基因12位密码子的4种基因型(野生型为GGT,突变型为AGT、TGT、CGT)质粒DNA为研究模型,采用SYBRGreenⅠ为实时PCR指示剂,进行ARMS实时PCR基因分型特异性的研究.结果表明:在和模板匹配的ARMS引物3′端附近引入故意错配碱基,... 以原癌基因Kras基因12位密码子的4种基因型(野生型为GGT,突变型为AGT、TGT、CGT)质粒DNA为研究模型,采用SYBRGreenⅠ为实时PCR指示剂,进行ARMS实时PCR基因分型特异性的研究.结果表明:在和模板匹配的ARMS引物3′端附近引入故意错配碱基,将ARMS引物浓度稀释10倍,并对传统三步PCR循环进行改良,即根据目的产物和引物二聚体的熔点差异,在传统延伸步骤之后增加一步恒温80℃检测荧光步骤,可消除引物二聚体的影响,使ARMS引物的特异性增强,得到清晰的基因分型结果.实验表明这种基于SYBRGreenⅠ的ARMS实时PCR基因分型方法,无需合成探针,实验设计简单,是一种快速、简便、经济、特异性好的基因分型方法,可推广用于其他基因的分型,并可望成为应用于临床的基因诊断技术之一. 展开更多
关键词 PCr Green SYBr rAS基因 DNA GGT 12 AGT TGT r基因
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Thin Layer Identification of Jiedu Shengxue Granules and Determination of Notoginsenoside R1 Content
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作者 Zhenying FU Bing QING +6 位作者 Yinghong HUANG Xianyi SHI Meiyan QIU Xian PENG Jiangcun WEI Fengzhen LI Wen ZHONG 《Medicinal Plant》 2024年第1期71-74,共4页
[Objectives]To establish the quality standard of hospital preparation Jiedu Shengxue granules.[Methods]Scleromitrion diffusum and Prunella vulgaris in Jiedu Shengxue granules were qualitatively identified by thin laye... [Objectives]To establish the quality standard of hospital preparation Jiedu Shengxue granules.[Methods]Scleromitrion diffusum and Prunella vulgaris in Jiedu Shengxue granules were qualitatively identified by thin layer chromatography(TLC).A high performance liquid chromatography(HPLC)was established to determine the content of notoginsenoside R1 in the granule.[Results]The traditional Chinese medicinal materials in Jiedu Shengxue granules could be identified by TLC,and the characteristic spots were stable and clear.Notoginsenoside R1 had a good linear relationship in the range of 10.45-104.5μg/mL,with an average recovery of 98.52%and RSD=2.36%.[Conclusions]TLC and HPLC,as the quality control methods of Jiedu Shengxue granules,have high accuracy and good repeatability,which lays a foundation for the quality control of this mixture. 展开更多
关键词 Jiedu Shengxue granules Thin layer identification notoginsenoside r1 Quality standard
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人恶性黑色素瘤A375细胞黑素刺激素受体(MC1R)的检测
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作者 李铁征 李泽鸿 +4 位作者 李月红 邱业峰 张培因 王树君 朱平 《中国生物制品学杂志》 CAS CSCD 2005年第3期200-204,共5页
目的检测人恶性黑色素瘤A375细胞膜上MC1R蛋白及其cDNA,为研究黑色素瘤细胞表面受体及靶向配体奠定基础。方法利用放射配体分析法检测人恶性黑色素瘤A375细胞膜上的MC1R蛋白;用RTPCR方法扩增人恶性黑色素瘤A375细胞MC1R的cDNA,并克隆至p... 目的检测人恶性黑色素瘤A375细胞膜上MC1R蛋白及其cDNA,为研究黑色素瘤细胞表面受体及靶向配体奠定基础。方法利用放射配体分析法检测人恶性黑色素瘤A375细胞膜上的MC1R蛋白;用RTPCR方法扩增人恶性黑色素瘤A375细胞MC1R的cDNA,并克隆至pMD18T质粒,进行酶切分析鉴定及扩增片段DNA序列测定。结果放射配体分析结果表明,125IαMSH可与人恶性黑色素瘤A375细胞膜特异结合。RTPCR结果显示,扩增产物的大小与MC1R的cDNA相符。测序结果证实扩增片段为MC1R基因的特异片段。结论证实人恶性黑色素瘤A375细胞膜上表达MC1R蛋白。MC1R基因的成功克隆为其进一步研究提供了必要条件。 展开更多
关键词 rT-PCr方法 MCIr基因 DNA cDNA r蛋白
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深海沉积物中产淀粉酶细菌的rep-PCR基因指纹分析 被引量:5
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作者 戴世鲲 郑天凌 +1 位作者 郑伟 王晓颖 《厦门大学学报(自然科学版)》 CAS CSCD 北大核心 2005年第B06期171-174,共4页
利用淀粉酶筛选培养基平板从27个深海沉积物样品中筛选得到30个具有胞外淀粉酶活性的菌株.其中革兰氏阴性细菌有22株,阳性细菌有8株.对这些细菌的基因组DNA进行ERICPCR和BOXPCR扩增,指纹图谱显示大部分菌株均存在数目不等的各自独特的带... 利用淀粉酶筛选培养基平板从27个深海沉积物样品中筛选得到30个具有胞外淀粉酶活性的菌株.其中革兰氏阴性细菌有22株,阳性细菌有8株.对这些细菌的基因组DNA进行ERICPCR和BOXPCR扩增,指纹图谱显示大部分菌株均存在数目不等的各自独特的带型,各特异性扩增的主带型能重复稳定出现.比较两种引物的指纹图谱,显示ERICPCR比BOXPCR具有较丰富的图谱多态性.对产生的指纹图谱进行聚类学分析,30株细菌可分为10组,其中5株细菌分别独立成组,最多的第Ⅱ组包含有8株细菌,而在同一聚类组内的细菌可能是处于进化上亲缘关系较近的位置.研究显示,30株菌具有丰富的种属多样性,揭示了深海微生物资源的丰富和潜力.ERICPCR和BOXPCR技术可用于对深海微生物群落组成和多样性的研究. 展开更多
关键词 r基因 rep ErIC DNA PCr扩增 PCr技术 BOX
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用R290与R152a混和制冷剂替代R22 被引量:9
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作者 王松岭 论立勇 +1 位作者 谢英柏 范忠瑶 《天然气工业》 EI CAS CSCD 北大核心 2005年第7期115-118,共4页
R22(俗称氟利昂)因在空调温区内具有优越的物理特性和热力循环性能,在制冷空调领域得到了广泛应用,但由于其会引起臭氧层破坏和温室效应,因此按照《蒙特利尔议定书》和《京都议定书》的规定将被停止生产和禁用。目前替代R22应用比较广... R22(俗称氟利昂)因在空调温区内具有优越的物理特性和热力循环性能,在制冷空调领域得到了广泛应用,但由于其会引起臭氧层破坏和温室效应,因此按照《蒙特利尔议定书》和《京都议定书》的规定将被停止生产和禁用。目前替代R22应用比较广泛的是R407C和R410A。文章提出了一种由丙烷R290和二氟乙烷R152a 组成的混和制冷剂来替代R22,通过分析该混和制冷剂的环境影响指数、温度滑移特性、热力学特性、安全特性和润滑油等问题,经理论循环计算并与R407C和R410A进行了对比,结果认为:由质量分数为65%的R290和质量分数为35%的R152a组成的混和制冷剂是一种对环境危害很小,温度滑移很小,具有合适的压比和性能系数(COP),润滑特性很好的优良近共沸制冷剂,用于替代R22各项指标均优于R407C和R410A。 展开更多
关键词 r290 r22 r410A r407C
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GRAPES模式标准初始化方案设计与实现 被引量:39
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作者 黄丽萍 伍湘君 金之雁 《应用气象学报》 CSCD 北大核心 2005年第3期374-384,共11页
文章介绍了GRAPES模式标准初始化系统的方案设计及程序结构,对3种不同方案产生的初始场进行了分析。结果表明:水平风场、温度场、位温场对插值方法的精度并不是很敏感,而高度场以及气压Exner函数则对垂直插值方法的精度要求很高;在3种... 文章介绍了GRAPES模式标准初始化系统的方案设计及程序结构,对3种不同方案产生的初始场进行了分析。结果表明:水平风场、温度场、位温场对插值方法的精度并不是很敏感,而高度场以及气压Exner函数则对垂直插值方法的精度要求很高;在3种模式变量产生方案中,方案一的效果较差,但它计算速度快,在地形梯度不大的地方可以选择使用;方案二与方案三的效果则比较好,用户可根据自己的需求任意选择。GRAPES模式标准初始化系统在完成其主要功能的同时,通过灵活的程序设计,对标准初始化系统的区域、分辨率、垂直层次、水平插值方法、垂直插值方法等的任意选取,使得标准初始化系统可以很容易满足模式初值的各种需求,为模式开发研究实验提供了各种便利。 展开更多
关键词 S 使 r函数
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清热燥湿方对急性肺损伤大鼠肺组织核转录因子-κB蛋白及mRNA表达的影响 被引量:10
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作者 阮琼 汪东颖 +4 位作者 杨爱东 李文雯 吴中华 郭永洁 王利霞 《中国中西医结合急救杂志》 CAS 北大核心 2010年第2期87-89,共3页
目的 探讨清热燥湿方对脂多糖(LPS)诱导的急性肺损伤(ALI)大鼠肺组织核转录因子-κB(NF-κB)蛋白及mRNA表达的影响.方法 40只雄性Wistar大鼠按随机数字表法均分为对照组、模型组、地塞米松组、清热燥湿方组4组.地塞米松和清热燥湿方在LP... 目的 探讨清热燥湿方对脂多糖(LPS)诱导的急性肺损伤(ALI)大鼠肺组织核转录因子-κB(NF-κB)蛋白及mRNA表达的影响.方法 40只雄性Wistar大鼠按随机数字表法均分为对照组、模型组、地塞米松组、清热燥湿方组4组.地塞米松和清热燥湿方在LPS诱导ALI模型前预处理3 d.分别于制模后4 h和8 h采用免疫组化法和逆转录-聚合酶链反应(RT-PCR)检测NF-κB的蛋白及mRNA表达,并进行肺组织病理观察.结果 与模型组相比,地塞米松组和清热燥湿方组4 h、8 h NF-κB蛋白染色阳性面积率[4 h:(3.40±0.39)%、(2.59±0.62)%比(4.28±0.55)%;8 h:(3.04±0.74)%、(2.60±0.11)%比(4.20±0.62)%]及mRNA表达[4 h:(12.88±2.28)×10-4、(3.07±2.63)×10-4比(44.82±9.27)×10-4;8 h:(3.30±2.64)×10-4、(1.53±1.51)×10-4比(26.07±3.81)×10-4]均明显降低(P<0.05或P<0.01).光镜下观察,模型组大鼠肺组织出现大片出血及坏死;清热燥湿方组大鼠肺组织病理损伤程度较模型组减轻.结论 清热燥湿方能减轻内毒素致ALI大鼠肺组织损伤,对肺损伤有保护作用,其机制可能与其能降低损伤肺组织NF-κB蛋白及mRNA表达有关. 展开更多
关键词 湿 MrNA表达 acute lung injury Wistar大鼠 ALI
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Effect of notoginsenoside R1 on hepatic microcirculation disturbance induced by gut ischemia and reperfusion 被引量:18
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作者 Wei-Xing Chen Fang Wang, Yu-Ying Liu, Qing-Jiang Zeng, Kai Sun, Xin Xue, Xiang Li, Ji-Ying Yang, Li-Hua An,Bai-He Hu, Jin-Hui Yang, Chuan-She Wang, Zhi-Xin Li, Lian-Yi Liu, Yan Li, Jun Zheng, Fu-Long Liao, Dong Han,Jing-Yu Fan, Jing-Yan Han Fang Wang +17 位作者 Yu-Ying Liu Qing-Jiang Zeng Kai Sun Xin Xue Xiang Li Ji-Ying Yang Li-Hua An Bai-He Hu Jin-Hui Yang Chuan-She Wang Zhi-Xin Li Lian-Yi Liu Yan Li Jun Zheng Fu-Long Liao Dong Han Jing-Yu Fan Jing-Yan Han 《World Journal of Gastroenterology》 SCIE CAS CSCD 2008年第1期29-37,共9页
AIM: To assess the effect of notoginsenoside R1 on hepatic microcirculatory disturbance induced by gut ischemia/reperfusion (I/R) in mice. METHODS: The superior mesenteric artery (SMA) of C57/BL mice was ligated... AIM: To assess the effect of notoginsenoside R1 on hepatic microcirculatory disturbance induced by gut ischemia/reperfusion (I/R) in mice. METHODS: The superior mesenteric artery (SMA) of C57/BL mice was ligated for 15 min to induce gut ischemia followed by 30-rain reperfusion. In another set of experiments, R1 was continuously infused (10 mg/kg per hour) from 10 min before I/R until the end of the investigation to study the influence of R1 on hepatic microcirculatory disturbance induced by gut I/R. Hepatic microcirculation was observed by inverted microscopy, and the vascular diameter, red blood cell (RBC) velocity and sinusoid perfusion were estimated. Leukocyte rolling and adhesion were observed under a laser confocal microscope. Thirty and 60 min after reperfusion, lactate dehydrogenase (LDH), alanine aminotransferase (ALl') and aspartate transaminase (AST) in peripheral blood were determined. The expression of adhesion molecules CD11b/CD18 in neutrophils and tumor necrosis factor- alpha (TNF-α), interleukin-6 (IL-6) and monocyte chemotactic protein-1 (MCP-1) in plasma were evaluated by flow Oltometry. E-selectin and intercellular adhesion molecule-1 (ICAM-1) in hepatic tissue were examined by immunofluorescence.RESULTS: After gut I/R, the diameters of terminal portal venules and central veins, RBC velocity and the number of perfused sinusoids were decreased, while the leukocyte rolling and adhesion, the expression of E-selectin in hepatic vessels and CD18 in neutrophils, IL-6, MCP-1, LDH, ALT and AST were increased. R1 treatment attenuated these alterations except for IL-6 and MCP-1. CONCLUSION: R1 prevents I/R-induced hepatic microcirculation disturbance and hepatocyte injury, The effect of R1 is related to its inhibition of leukocyte rolling and adhesion by inhibiting the expression of E-selectin in endothelium and CD18 in neutrophils. 展开更多
关键词 ISCHEMIA/rEPErFUSION notoginsenoside r1 Leukoytes adhesion E-SELECTIN Hepatic injury
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郯庐断裂带肥东段走滑运动的^(40)Ar/^(39)Ar法定年 被引量:77
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作者 朱光 牛漫兰 +3 位作者 刘国生 王勇生 谢成龙 李长城 《地质学报》 EI CAS CSCD 北大核心 2005年第3期303-316,共14页
郯庐断裂带在华北与华南板块碰撞之后是否发生过大规模左行平移及其准确的时间,仍然是存在着争议的重要问题。郯庐断裂肥东段地表出露了大规模的、北北东走向的韧性剪切带。野外构造、显微构造与石英C轴组构分析皆指示为左旋走滑韧性剪... 郯庐断裂带在华北与华南板块碰撞之后是否发生过大规模左行平移及其准确的时间,仍然是存在着争议的重要问题。郯庐断裂肥东段地表出露了大规模的、北北东走向的韧性剪切带。野外构造、显微构造与石英C轴组构分析皆指示为左旋走滑韧性剪切带。糜棱岩中变形矿物组合与矿物变形行为指示该韧性剪切带形成于中—高绿片岩相环境。通过对该段走滑糜棱岩中角闪石与黑云母的40Ar/39Ar年代学研究,本次工作中获得了一个角闪石(N14)的40Ar/39Ar坪年龄为143.3±1.3Ma(早白垩世初),据变形温度判断其代表了该断裂带左行平移中的变形年龄。该糜棱岩(N14)中新生的黑云母40Ar/39Ar坪年龄为134.1±0.6Ma,而同一采场中另一糜棱岩(N13)中新生黑云母40Ar/39Ar坪年龄为130.3±0.6Ma,皆指示了左行平移活动的冷却年龄。另外4处走滑糜棱岩中黑云母的40Ar/39Ar坪年龄分别为137.2±0.8Ma(N47)、135.6±0.6Ma(N17)、124.8±0.7Ma(N21)和125.9±0.4Ma(N22),也都属于冷却年龄,反映了该走滑韧性剪带内的不均匀冷却现象。由此变形年龄与冷却年龄可以判断该断裂带的左行平移持续时间不超过6Ma左右。由N14糜棱岩中的角闪石与黑云母坪年龄得到该处的平均冷却速率为21.7℃/Ma,属于较快速的冷却。本次40Ar/39Ar测年结果。 展开更多
关键词 ^40Ar/^39Ar年代学 ^40Ar/^39Ar测年 r 绿
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mRNA差异显示技术的研究进展 被引量:7
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作者 陈永华 严钦泉 +1 位作者 余建蒲 肖国樱 《西北农业学报》 CAS CSCD 北大核心 2005年第2期9-12,43,共5页
针对mRNA差异显示技术中的假阳性高和放射性污染等缺陷,文章从改进引物设计、应用非放射性标记、优化PCR参数、假阳性鉴定等方面进行了综述。1采用4种兼并或单碱基引物作锚定引物;用特异和长序列(≥20bp)专一性引物作为随机引物,可增加... 针对mRNA差异显示技术中的假阳性高和放射性污染等缺陷,文章从改进引物设计、应用非放射性标记、优化PCR参数、假阳性鉴定等方面进行了综述。1采用4种兼并或单碱基引物作锚定引物;用特异和长序列(≥20bp)专一性引物作为随机引物,可增加特异性;在锚定引物之前加上了一段T7启动子序列,在随机引物前加上一段M13重复序列,可使DDRT—PCR的体系的扩增特异性更一致。2针对放射性同位素检测法的缺点,文章提出并比较了几种常用的非放射性同位素标记方法。3保证起始(模板)mRNA质量和浓度,降低dNTP浓度,选择最适的反转录和PCR退火温度,可优化PCR参数。4用两种不同的反转录酶进行反转录平行实验,很容易区分出RNA制备过程中造成的假阳性,目前假阳性鉴定大多还是以Northern印迹为基础,再作些适当的改进。 展开更多
关键词 MrNA差异显示技术 NOrTHErN dNTP 退 r参数 PCr
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Comparative Study of Radiological Changes in Hands and Feet in Patients Suffering from Early Rheumatoid Arthritis by Power Doppler Ultrasound and Direct Digital Radiography
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作者 Gargy Mondal Biswadip Ghosh +1 位作者 Manoranjan Ghosh Pampa Halder 《Open Journal of Rheumatology and Autoimmune Diseases》 2014年第1期39-42,共4页
Rheumatoid arthritis is a chronic multisystem disease of unknown cause. The characteristic feature of RA is persistent inflammatory synovitis. The natural history of disease is such that the early months of the diseas... Rheumatoid arthritis is a chronic multisystem disease of unknown cause. The characteristic feature of RA is persistent inflammatory synovitis. The natural history of disease is such that the early months of the disease are critical period during which reversible joint damage occurs. So early diagnosis of RA and appropriate drug application is the only way to save a patient from this crippling disease. In India, the cost of investigations is a significant factor for most of the patients. Ultrasonography or Power Doppler Ultra Sound (PDUS) has the advantage of being economic in spite of its sensitivity in assessing both inflammatory and destructive changes. The aim of the present study was to evaluate the diagnostic efficiency of PDUS in early rheumatoid arthritis. The study was performed with the patients attending Rheumatology Clinic. A total number of 106 patients of clinically suspected rheumatoid arthritis were studied as per selection criteria. Radiological examinations of hands were done by digital radiography and PDUS in a group of 53 patients, assessment of foot changes by PDUS and Digital Radiography were done in another similar group of 53 patients. Final diagnosis by ACR EULAR-2010 criteria is done for all the patients. The comparative study reveals that synovial vascularity as demonstrated by PDUS is much more effective in diagnosing early rheumatoid arthritis, both in hand and in feet than digital radiograph. PDUS of feet may yield earlier and better findings than hands, which is conventionally used in patients suffering from early rheumatoid arthritis. 展开更多
关键词 r.A.—rheumatoid Arthritis PDUS—Power Doppler Ultrasound D.r.—Digital radiography ACr-EULAr—American College of rHEUMATOLOGY (ACr) and the European LEAGUE against rHEUMATISM (EULAr) rF—rheumatoid Factor CrP—c-reactive Protein MrI—Magnetic resonance Imaging
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长沙气温的长期变化趋势及R/S分析 被引量:7
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作者 左利芳 《长沙理工大学学报(自然科学版)》 CAS 2005年第2期90-96,共7页
运用三阶幂函数和R/S分析法,对1951年以来长沙1月、7月和年平均的气温进行了分析.研究结果表明:①长沙气温总体呈上升趋势,增暖幅度与全国平均增暖幅度持平.20世纪90年代以前偏冷,20世纪90年代开始变暖,近10年变暖加剧.②长沙1月气温呈... 运用三阶幂函数和R/S分析法,对1951年以来长沙1月、7月和年平均的气温进行了分析.研究结果表明:①长沙气温总体呈上升趋势,增暖幅度与全国平均增暖幅度持平.20世纪90年代以前偏冷,20世纪90年代开始变暖,近10年变暖加剧.②长沙1月气温呈上升趋势,而7月气温呈下降趋势,1月气温变化对年平均气温变化的贡献大于7月.③R/S分析的结果得出,1月H值略小于0 5,说明冬季气温呈波动性变化;而7月和年平均H值达0 81,存在明显的Hurst现象,气温变化趋势具有持续性,7月气温将延续下降趋势,年平均气温将延续上升趋势. 展开更多
关键词 2090 Hurst现象 r/S分析法 H
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The Analysis of Human Development Index (HDI) for Categorizing the Member States of the United Nations (UN)
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作者 Sivarajah Mylevaganam 《Open Journal of Applied Sciences》 2017年第12期661-690,共30页
To categorize the nations to reflect the development status, to date, there are many conceptual frameworks. The Human Development index (HDI) that is published by the United Nations Development Programme is widely acc... To categorize the nations to reflect the development status, to date, there are many conceptual frameworks. The Human Development index (HDI) that is published by the United Nations Development Programme is widely accepted and practiced by many people such as academicians, politicians, and donor organizations. However, though the development of HDI has gone through many revisions since its formulation in 1990, even the current version of the index formulation published in 2016 needs research to better understand and to gap-fill the knowledge base that can enhance the index formulation to facilitate the direction of attention such as release of funds. Therefore, in this paper, based on principal component analysis and K-means clustering algorithm, the data that reflect the measures of life expectancy index (LEI), education index (EI), and income index (II) are analyzed to categorize and to rank the member states of the UN using R statistical software package, an open source extensible programming language for statistical computing and graphics. The outcome of the study shows that the proportion of total eigen value (i.e., proportion of total variance) explained by PCA-1 (i.e., first principal component) accounts for more than 85% of the total variation. Moreover, the proportion of total eigen value explained by PCA-1 increases with time (i.e., yearly) though the amount of increase with time is not significant. However, the proportions of total eigen value explained by PCA-2 and PCA-3 decrease with time. Therefore, the loss of information in choosing PCA-1 to represent the chosen explanatory variables (i.e., LEI, EI, and II) may diminish with time if the trend of increasing pattern of proportion of total eigen value explained by PCA-1 with time continues in the future as well. On the other hand, the correlation between EI and PCA-1 increases with time although the magnitude of increase is not that significant. This same trend is observed in II as well. However, in contrast to these observations, the correlation between PCA-1 and LEI decreases with time. These findings imply that the contributions of EI and II to PCA-1 increase with time, but the contribution of LEI to PCA-1 decreases with time. On top of these, as per Hopkins statistic, the clusterability of the information conveyed by PCA-1 alone is far better than the clusterability of the information conveyed by PCA scores (i.e., PCA-1, PCA-2, and PCA-3) and the explanatory variables. Therefore, choosing PCA-1 to represent the chosen explanatory variables is becoming more concrete. 展开更多
关键词 Human DEVELOPMENT Index Economy Sustainability UNITED Nations DEVELOPMENT Programme Education Life EXPECTANCY Per Capita INCOME JavaScript r Statistical Software Principal Component ANALYSIS K-Means Clustering HOPKINS Statistic
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Different Concentrations of Notoginsenoside Rg1 Attenuate Hypoxic and Hypercapnia Pulmonary Hypertension by Reducing the Expression of ERK in Rat PASMCs 被引量:1
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作者 Congcong Zhang Lixiao Ye +4 位作者 Haizhen Jin Meiping Zhao Mengxiao Zheng Longsheng Song Wantie Wang 《Advances in Biological Chemistry》 2016年第1期12-18,共7页
Pulmonary arterial hypertension (PAH) is a serious disease which is characterized by increased vascular resistance and pressure. We have previously hypothesized that panax notoginseng saponins (PNS) might attenuate pu... Pulmonary arterial hypertension (PAH) is a serious disease which is characterized by increased vascular resistance and pressure. We have previously hypothesized that panax notoginseng saponins (PNS) might attenuate pulmonary vasoconstriction under hypoxia and hypercapnia condition. This study aims to investigate the effect of notoginsenoside R<sub>g1</sub>, a main ingredient of PNS, with various concentrations (8, 40, 100 mg/L, respectively) on extracellular signal regulated kinase (ERK1/2) signaling pathway in pulmonary arterial smooth muscle cells (PASMCs). In addition, PASMCs were randomly divided into six groups: SD rat under normoxic condition as control group (N group), hypoxia hypercapnia group (H group), DMSO control group (HD group), R<sub>g1</sub>-treatment groups (R<sub>gL</sub>R<sub>gM</sub> and R<sub>gH</sub> group). Western-blot and RT-PCR were used to test the expression of p-ERK protein and the expression of ERK1 mRNA and ERK2 mRNA. This study provided the evidence that the expression of p-ERK protein and the expression of ERK1 mRNA and ERK2 mRNA in HD group and H group were obviously higher than that in N group (P < 0.01), Whereas the level of ERK1/2 mRNA in R<sub>g1</sub>-treatment groups was significantly lower than that in HD group and H group (P < 0.01), and the proper concentration of R<sub>g1</sub> is 40 mg/L. These results suggested that notoginsenoside R<sub>g1</sub> can attenuate pulmonary vasoconstriction which may lead to HHPV through reducing the expression of ERK1/2. 展开更多
关键词 Pulmonary Arterial Smooth Muscle Cells Hypoxia Hypercapnia ErK1/2 Signal Pathway notoginsenoside rg1 rats
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热分析方法研究人参皂苷Rg_3对映异构体的热特征 被引量:1
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作者 卢丹 刘金平 +1 位作者 赵莹 李平亚 《中草药》 CAS CSCD 北大核心 2005年第5期658-660,共3页
关键词 20(r)-人参皂苷rg3 20(S)-人参皂苷rG3 MEYEr
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R410A应用将成主流
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作者 于昊 《电器》 2005年第4期i010-i011,共2页
环保制冷剂的应用在发达国家已经备受重视。以空调用R410A为代表的环保制冷剂已经闪亮地走上了历史的舞台。
关键词 r410A CFC 1996 1992 2030 使 40 r22
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Thermodynamic Simulation of CCP in Air-Cooled Heat Pump Unit with HFCs and CO<sub>2</sub>Trans-Critical 被引量:2
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作者 Feihu Chen Shuguang Liao Guangcai Gong 《Journal of Power and Energy Engineering》 2018年第9期141-164,共24页
The exergy analysis and finite time thermodynamic methods had been employed to analyze the compound condensation process (CCP). It was based on the air-cooling heat pump unit. The cooling capacity of the chiller unit ... The exergy analysis and finite time thermodynamic methods had been employed to analyze the compound condensation process (CCP). It was based on the air-cooling heat pump unit. The cooling capacity of the chiller unit is about 1 kW, and the work refrigerant is R22/R407C/R410A/CO2. The MATLAB/SIMULINK software was employed to build the simulation model. The thermodynamic simulation model is significant for the optimization of parameters of the unit, such as condensation and evaporation temperature and mass flow of the sanitary hot water and size of hot water storage tank. The COP of the CCP of R410A system is about 3% - 5% higher than the CCP of the R22 system, while CCP of the R407C system is a little lower than the CCP of R22 system. And the CCP of CO2 trans-critical system has advantage in the hot supply mode. The simulation method provided a theoretical reference for developing the production of CCP with substitute refrigerant R407C/R410A/CO2. 展开更多
关键词 Air-Cooled Heat Pump Unit Compound Condensation Process (CCP) Exergy Analysis Method Sanitary Hot Water MATLAB/SIMULINK Software Fluorine SUBSTITUTE rEFrIGErANT r407C/r410A Natural rEFrIGErANT CO2
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IL-10对大鼠肝纤维化的治疗作用及对TNF-α、IGF-1及IGF-1R表达的影响 被引量:5
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作者 黄月红 张莉娟 +3 位作者 郑伟达 史美娜 陈治新 王小众 《胃肠病学和肝病学杂志》 CAS 2005年第3期249-252,共4页
目的外源性白介素10(IL10)对大鼠肝纤维化的治疗作用及对肿瘤坏死因子α(TNFα)和胰岛素样生长因子1(IGF1)及其受体(IGF1R)表达的影响。方法40只SD大鼠随机分为正常对照组和CCl4诱发肝纤维化模型组。至造模第9周,模型组随机分为3组,S组... 目的外源性白介素10(IL10)对大鼠肝纤维化的治疗作用及对肿瘤坏死因子α(TNFα)和胰岛素样生长因子1(IGF1)及其受体(IGF1R)表达的影响。方法40只SD大鼠随机分为正常对照组和CCl4诱发肝纤维化模型组。至造模第9周,模型组随机分为3组,S组造模结束即处死,I组IL10治疗2周后处死,R组为自然恢复2周后处死。通过HE染色评价各组肝纤维化的程度,SP免疫组化检测各组大鼠肝脏TNFα、IGF1、IGF1R表达情况。结果肝病理组织学显示:I组纤维化程度有明显改善,R组纤维化程度没有明显改善。TNFα、IGF1、IGF1R在S组表达显著升高(P<0.05),在R组及I组表达下降,但I组下降较R组明显,与R组比较差别有显著意义(P<0.05)。结论外源性IL10能明显抑制炎性细胞因子TNFα的表达和IGF1及IGF1R的表达,这可能是IL10对大鼠肝纤维化治疗作用的机制之一。 展开更多
关键词 IGF-1r -α(TNF-α) IL-10 CCL4 SD HE
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bFGF对人晶状体上皮细胞系内钙离子及IP3R、RyR的作用 被引量:5
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作者 曲勃 张劲松 《国际眼科杂志》 CAS 2005年第2期235-238,共4页
目的:探讨碱性成纤维细胞生长因子(bFGF)对人晶状体上皮细胞系LEC-B3内静息Ca2+浓度及三磷酸肌醇受体(IP3R)、ryanodine受体(RyR)表达的影响。方法:LEC-B3细胞系传代培养,分别以1,10,100μg/L bFGF诱导第3代细胞的增殖,MTT法检测其增殖... 目的:探讨碱性成纤维细胞生长因子(bFGF)对人晶状体上皮细胞系LEC-B3内静息Ca2+浓度及三磷酸肌醇受体(IP3R)、ryanodine受体(RyR)表达的影响。方法:LEC-B3细胞系传代培养,分别以1,10,100μg/L bFGF诱导第3代细胞的增殖,MTT法检测其增殖度,激光扫描共聚焦显微镜测细胞内静息钙浓度;RT-PCR(reverse-transcriptase,PCR)方法检测10μg/L bFGF作用后细胞内IP3R和RyRmRNA的表达。结果:与对照组相比,3个浓度的bFGF对LEC-B3都有促增殖作用(P<0.01),其中10μg/L作用最强;bFGF作用后细胞内Ca2+浓度呈bFGF浓度依赖性增高,10μg/L,100μg/LP<0.01,1μg/L<0.05;10μg/L bFGF作用后的细胞IP3RI mRNA表达无明显变化,III型表达明显减弱(P<0.01),ryan-odineRI,IIImRNA表达升高(P<0.05,0.01)。结论:bFGF诱导LEC-B3细胞增殖引起细胞内钙离子浓度增加。Ca2+升高呈bFGF浓度依赖性,并不与细胞增殖度平行。bFGF对IP3R和RyR亚型的mRNA表达有一定影响,并且细胞内Ca2+浓度升高与bFGF刺激RyRmRNA表达升高有关。 展开更多
关键词 IP3r (bFGF) ryanodine受体 rYr Ca^2%PLUS% MTT PCr) 3
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