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应力效应下页岩动静态弹性各向异性特征
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作者 边会媛 臧鑫 +3 位作者 张迪 张程恩 聂晓敏 武银婷 《物探与化探》 CAS 2024年第6期1664-1673,共10页
静态弹性力学参数是页岩油开采及注水压裂工程的关键参数,应力效应下各向异性对页岩动静态弹性特征具有重要的影响,开展储层动静态弹性特征的主控因素与控制机理研究是页岩油气开采及注水压裂工程中一项亟须解决的关键科学问题。通过不... 静态弹性力学参数是页岩油开采及注水压裂工程的关键参数,应力效应下各向异性对页岩动静态弹性特征具有重要的影响,开展储层动静态弹性特征的主控因素与控制机理研究是页岩油气开采及注水压裂工程中一项亟须解决的关键科学问题。通过不同加压方式下页岩的三轴压缩力学与声学联测实验,研究各向异性对页岩纵、横波速度及宏观力学性质的影响,探究页岩动静态弹性特征的响应规律。结果表明:①随压力的增加,页岩动、静态杨氏模量增大,且增大速率由快到慢趋于稳定值;②层理角度一定时,动态杨氏模量大于静态杨氏模量,二者呈正相关,动、静态泊松比关系较差;③岩石动、静态刚度系数均随围压增大而增大,与纵波相关的动态刚度系数C_(11)、C_(33)比与横波相关的动态刚度系数C_(44)、C_(66)变化更明显;④页岩动、静态各向异性均随围压的增大而增大。研究结果可以揭示页岩动、静态弹性特征响应机理,并能够为页岩油气储层开采与水力压裂改造提供关键力学参数。 展开更多
关键词 页岩油 各向异性 弹性性质 静态模量 地层压力
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Prevalence of isolated systolic hypertension and analysis on its relative factors in 1002 cases over 80 years old in retirement centers for army officers 被引量:17
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作者 LI Yan-fang CAO Jian +6 位作者 FAN Li BU Cong-ya LI Xi WANG Long-hua CHENG Xiu-qin nie xiao-min WU Xiao-ying 《Chinese Medical Journal》 SCIE CAS CSCD 2006年第17期1473-1476,共4页
Nowadays, despite the high prevalence of hypertension, the awareness rate and control rate of this disease are still very low. In addition, the prevalence of hypertension in old population is very high, and most of ca... Nowadays, despite the high prevalence of hypertension, the awareness rate and control rate of this disease are still very low. In addition, the prevalence of hypertension in old population is very high, and most of cases are isolated systolic hypertension (ISH). We investigated people ranging in age from 80 to 99 years in 28 cadre retirement centers in Beijing to study the prevalence and incidence of target organ injury and analyze the relative factors of ISH. 展开更多
关键词 blood pressure HYPERTENSION population surveillance
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Kruppel-like factor 2 might mediate the rapamycin-induced arterial thrombosis in vivo: implications for stent thrombosis in patients
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作者 nie xiao-min SU Li-xiao +3 位作者 XU Rui-xia GUO Yuan-lin ZHOU Yu-jie LI Jian-jun 《Chinese Medical Journal》 SCIE CAS CSCD 2013年第14期2636-2640,共5页
Background Stent thrombosis is one of severe complications after sirolimus-eluting stent implantation. Rapamycin (sirolimus) promotes arterial thrombosis in in vivo studies. However, the underlying molecular and tra... Background Stent thrombosis is one of severe complications after sirolimus-eluting stent implantation. Rapamycin (sirolimus) promotes arterial thrombosis in in vivo studies. However, the underlying molecular and transcriptional mechanisms of this adverse effect have not been thoroughly investigated. This study was designed to examine the effects of rapamycin on the expression of the gene, Kruppel-like factor 2 (KLF2), and its transcriptional targets in mice. Methods Mice were randomly divided into four groups: the control group (intraperitoneal injection with 2.5% of dimethyl sulfoxide (DMSO) only), rapamycin group (intraperitoneal injection with 2 mg/kg of rapamycin only), Ad-LacZ + rapamycin group (carotid arterial incubation with Ad-LacZ plus intraperitoneal injection with 2 mg/kg of rapamycin 10 days later), and Ad-KLF2 + rapamycin group (carotid arterial incubation with Ad-KLF2 plus intraperitoneal injection with 2 mg/kg rapamycin 10 days later). The carotid arterial thrombosis formation was induced by FeCI3 and the time of arterial thrombosis was determined. Finally, the RNA and protein of carotid arteries were extracted for KLF2, tissue factor (TF), plasminogen activator inhibitor-1 (PAl-l), endothelial nitric oxide synthase (eNOS), thrombomodulin (TM) mRNA and protein analysis. Results Compared with controls, treatment with rapamycin inhibited KLF2, eNOS and TM mRNA and protein expression, and enhanced TF and PAl-1 mRNA and protein expression, and shortened time to thrombotic occlusion from (1282+347) seconds to (715+120) seconds (P 〈0.01) in vivo. Overexpression of KLF2 strongly reversed rapamycin-induced effects on KLF2, eNOS, TM, TF and PAl-1 expression. KLF2 overexpression increased the time to thrombotic occlusion to control levels in vivo. Conclusions Rapamycin induced an inhibition of KLF2 expression and an imbalance of anti- and pro-thrombotic gene expression, which promoted arterial thrombosis in vivo. Overexpression of KLF2 increased KLF2 expression and reversed time to thrombosis in vivo. 展开更多
关键词 RAPAMYCIN Krupple-like factor 2 THROMBOSIS gene expression ADENOVIRUS
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