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排序方式: 共有383条查询结果,搜索用时 15 毫秒
1.
李弘  刘叶倩  龚姗  刘林  曾勇  蔡晓  王宇红  任卫琼 《金属学报》2019,24(12):1364-1370
目的:探究复方七芍降压片对自发性高血压大鼠(SHR)血压及血管重塑的作用机制。方法:SHR大鼠随机分为模型组、厄贝沙坦片组、复方七芍降压片组,每组10只,另设10只WKY大鼠为正常对照组,给药6周,无创血压仪测量各周大鼠血压变化;HE染色观察大鼠肠系膜动脉病理变化并测量管壁厚度、血管中膜厚度及相同位置的管腔直径,比值记为WT;免疫组化法检测肠系膜动脉中基质金属蛋白酶-2(MMP-2)及Ⅰ、Ⅲ型胶原蛋白(COⅠ、COⅢ)表达情况。结果:给药6周后,与正常对照组比较,模型组大鼠各周血压均明显升高(P<0.01),管壁厚度及WT值增高(P<0.01或P<0.05),肠系膜动脉中MMP-2及Ⅰ、Ⅲ型胶原蛋白表达均明显升高(P<0.01);与模型组比较,复方七芍降压片组大鼠各周血压均明显降低(P<0.01),管壁厚度及WT值降低(P<0.05),肠系膜动脉中MMP-2及Ⅰ、Ⅲ型胶原蛋白表达均明显降低(P<0.05),且病理变化得到改善。结论:复方七芍降压片具有降低SHR大鼠血压,改善血管重塑的作用,其机制可能与降低MMP-2表达及Ⅰ、Ⅲ型胶原蛋白沉积有关。  相似文献   
2.
Atherothrombosis exposes vascular components to blood. Currently, new antithrombotic therapies are emerging. Herein we investigated thrombogenesis of human arteries with/without atherosclerosis, and the interaction of coagulation and vascular components, we and explored the anti-thrombogenic efficacy of blockade of the P2X purinoceptor 7 (P2X7). A confocal blood flow videomicroscopy system was performed on cryosections of internal mammary artery (IMA) or carotid plaque (CPL) determining/localizing platelets and fibrin. Blood from healthy donors elicited thrombi over arterial layers. Confocal microscopy associated thrombus with tissue presence of collagen type I, laminin, fibrin(ogen) and tissue factor (TF). The addition of antibodies blocking TF (aTF) or factor XI (aFXI) to blood significantly reduced fibrin deposition, variable platelet aggregation and aTF + aFXI almost abolished thrombus formation, showing synergy between coagulation pathways. A scarce effect of aTF over sub-endothelial regions, more abundant in tissue TF and bundles of laminin and collagen type I than deep intima, may suggest tissue thrombogenicity as molecular structure-related. Consistently with TF-related vascular function and expression of P2X7, the sections from CPL but not IMA tissue cultures pre-treated with the P2X7 antagonist A740003 demonstrated poor thrombogenesis in flow experiments. These data hint to local targeting studies on P2X7 modulation for atherothrombosis prevention/therapy.  相似文献   
3.
《Planning》2019,(5)
目的探讨彩色多普勒超声测量肾脏叶间动脉阻力指数(resistance index,RI)对Ⅰ型心肾综合征(cardiorenal syndrome,CRS)的诊断价值。方法选取2017年6月1日至2018年3月1日收住民航总医院急诊综合病房并诊断为Ⅰ型CRS的20例患者作为试验组(CRS组),选取同期诊断为单纯急性心力衰竭的患者20例作为对照组,分析两组患者的临床特征、实验室检查及用药情况,并根据受试者工作特征(receiver operating characteristic,ROC)曲线评价肾动脉RI对Ⅰ型CRS的诊断价值。结果两组患者年龄、左心室射血分数、心功能分级、心率及脉压差差异无统计学意义(P均>0. 05),CRS组患者的氨基末端脑钠尿肽、肌酐水平、呋塞米剂量以及肾动脉RI均高于对照组,而肾小球滤过率低于对照组,差异具有统计学意义(P均<0. 05)。ROC曲线下面积为0. 78,取最佳截点值0. 70时预测Ⅰ型CRS的敏感度为80%,特异度为80%。结论作为一种新的手段,肾动脉RI可与传统方法相互补充,对诊断Ⅰ型心肾综合征患者具有潜在应用价值。  相似文献   
4.
Left ventricular (LV) remodeling after myocardial infarction constitutes the structural basis for ventricular dysfunction and heart failure. The characterization underlying the expression of lipoprotein receptors in cardiac dysfunction is scarcely explored. The aim of this study was to analyze the status of lipoprotein receptors on the infarcted and noninfarcted areas of LV and to verify whether nanoparticles that mimic the lipid structure of low‐density lipoprotein (LDL) and have the ability to bind to LDL receptors (LDE) are taken up more avidly by the noninfarcted LV. 13 male Wistar rats with left coronary artery ligation (myocardial infarction [MI]) and 12 animals with SHAM operation (SHAM) were used in this study. 6 weeks after the procedure, the quantification of low‐density lipoprotein receptor (LDLR), LDL receptor‐related protein 1 (LRP1), scavenger receptor‐class B type I (SR‐BI) lipoprotein receptors, and PCNA proliferation marker, and tissue uptake of radioactively labeled LDE were performed. Immunohistochemistry and Western blot analysis showed that LDLR, LRP1, SR‐BI, and PCNA, expression in infarcted area of MI was remarkably higher than SHAM and noninfarcted subendocardial (SEN) and interstitial (INT) areas. In addition, in SEN noninfarcted area of MI, the presence of LDLR was about threefold higher than in SHAM SEN and INT noninfarcted areas. The LDE uptake of noninfarcted LV of MI group was about 30% greater than that of SHAM group. In conclusion, these findings regarding the status of lipoprotein receptors after MI induction could help to establish mechanisms on myocardial repairing. In conclusion, infarcted rats with LV dysfunction showed increased expression of lipoprotein receptors mainly in the infarcted area.  相似文献   
5.
The limitations of newly synthesized biodegradable stents are low mechanical strength, fracture stiffness, and fast degradability of the polymers. A cylindrical polymeric scaffold was proposed in combination of polylactic acid and polycaprolactone. The tensile strength of the blend was increased twice, though elongation has reduced threefold. The blend illustrated no chemical interaction between polymers. The scaffold was coated with docetaxel, and sustained release profile was observed for 56 days. The degradation of the scaffold was evaluated through change in mechanical properties, weight variation, and morphological studies. The developed hemocompatible polymeric scaffold may be used as for the cardiovascular application.  相似文献   
6.
ABSTRACT

This paper focuses on the social aspects of food consumption in the public realm and how built environment design should include places for conviviality. Current urban planning may fulfil human needs, but in some cases, individuals have unpleasant experiences while meeting these needs. A review of existing literature indicates that studies of conviviality during food consumption has focused on design qualities. To investigate the Egyptian experiences in food consumption, the current study employed qualitative and quantitative approaches through four streams of data collection: observations, interviews, opinionnaire and permeability analysis of catchment areas. The results provide design implications for conviviality of food practices to discover the multilateral dimensions of design that can make social interactions part of a satisfying experience. This research concludes that for conviviality attached to food consumption, it is essential to focus on replicable aspects like supporting activities, social settings, and the design based on intent.  相似文献   
7.
刘洋  陈明骏  宋翔  刘宏斌 《食品科学》2018,39(9):170-175
目的:探讨叶黄素对颈动脉粥样硬化斑块炎性反应程度的影响。方法:连续纳入于解放军总医院就诊的颈动脉粥样硬化患者169名,随机分为安慰剂组(淀粉胶囊,1次/日)、低剂量组(叶黄素20 mg,1次/日)、中剂量组(叶黄素40 mg,1次/日)、高剂量组(叶黄素60 mg,1次/日)。每名患者分别于确定参加实验的1周内及服药结束后行血液样本采集以及正电子发射断层显像(positron emission tomography-computed tomography,PET-CT)技术检查。服药期为12个月。对每名患者实验开始及实验结束的两次血液学标本均进行血常规、血生化、炎性因子及药物浓度方面的检测。颈动脉斑块PET-CT检查,计算18氟-脱氧葡萄糖摄取值的标准化值(target-to-background ratio,TBR),以此反映斑块炎性反应程度。结果:叶黄素干预后,低、中、高剂量3组患者的叶黄素血药浓度均显著升高。与正常组及自身服药前的基线水平相比较,叶黄素干预后的低、中、高剂量3组患者TBR均显著降低,而且干预剂量越大,TBR的降低越明显。结论:叶黄素可以减轻颈动脉粥样硬化斑块的炎性反应程度,对心脑血管事件的发生具有一定的预防作用。  相似文献   
8.
The aim of our study was to analyze mitochondrial and endoplasmic reticulum (ER) gene expression profiles in subcutaneous (SAT) and epicardial (EAT) adipose tissue, skeletal muscle, and myocardium in patients with and without CAD undergoing elective cardiac surgery. Thirty-eight patients, 27 with (CAD group) and 11 without CAD (noCAD group), undergoing coronary artery bypass grafting and/or valvular surgery were included in the study. EAT, SAT, intercostal skeletal muscle, and right atrium tissue and blood samples were collected at the start and end of surgery; mRNA expression of selected mitochondrial and ER stress genes was assessed using qRT-PCR. The presence of CAD was associated with decreased mRNA expression of most of the investigated mitochondrial respiratory chain genes in EAT, while no such changes were seen in SAT or other tissues. In contrast, the expression of ER stress genes did not differ between the CAD and noCAD groups in almost any tissue. Cardiac surgery further augmented mitochondrial dysfunction in EAT. In our study, CAD was associated with decreased expression of mitochondrial, but not endoplasmic reticulum stress genes in EAT. These changes may contribute to the acceleration of coronary atherosclerosis.  相似文献   
9.
YKL-40, a pleotropic cytokine, is emerging as a risk factor and a prognostic predictor of atherosclerotic cardiovascular disease. We attempted to elucidate the genetic, clinical and biochemical correlates of circulating YKL-40 level and, by combining it with CHI3L1 gene variants, with the risk and long-term mortality of peripheral artery disease (PAD). Plasma YKL-40 concentrations were measured in 612 Taiwanese individuals who had no clinically overt systemic disease. Clinical parameters, CHI3L1 gene promoter variants and 18 biomarker levels were analyzed. Eighty-six PAD patients were further enrolled for analysis. Significant associations were found between CHI3L1 genotypes/haplotypes and YKL-40 levels for the health examination subjects (smallest p = 8.36 × 10−7 for rs4950928 and smallest p = 1.72 × 10−10 for haplotype TGG) and also for PAD patients. For the health examination subjects, circulating YKL-40 level, but not CHI3L1 gene variants, were positively associated with age, smoking, and circulating levels of triglyceride, lipocalin 2 and multiple inflammatory biomarkers and negatively associated with low-density-lipoprotein cholesterol levels. Circulating YKL-40 level is also significantly associated with the risk of PAD (p = 3.3 × 10−23). Circulating YKL40 level, but not CHI3L1 gene promoter variants, is associated with the risk of PAD in Taiwanese. The association of YKL-40 levels with multiple quantitative traits relating to the risk of PAD may provide a molecular basis linking YKL-40 to atherosclerotic cardiovascular disease.  相似文献   
10.
冠状动脉性心脏病简称冠心病,属于心脑血管疾病中的常见病,会严重地危害人们的身体健康,目前已经成为引发人类死亡的重大疾病之一。根据段富津教授历年来治疗冠心病病例中药方剂数据为研究样本,采用最普通常见的数据挖掘方法——决策树分类方法,从海量冠心病中医临床诊疗数据中高效地挖掘出蕴含数据中的潜在关联规则,最终将产生的关联规则恰到好处地应用于冠心痛的中医临床诊断中。  相似文献   
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