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991.
Patients with end‐stage renal failure (ESRF) undergoing haemodialysis (HD) are repeatedly exposed to stress and pain from approximately 300 punctures per year to their arteriovenous fistula (AVF). Repeated AVF punctures lead to a considerable degree of pain, due to the calibre and length of the bevel of fistula needles. Pain is a sensitive, emotional and subjective experience. The objective of this study was to measure pain associated with AVF needling. The analogue visual scale (AVS) divided into 10 equal parts (0 indicating lack of pain, and 10 unbearable pain) was used. Patients7 perceptions were measured in three different HD sessions. Pain was considered mild during AVF needling. The buttonhole technique caused a mean degree of pain of 2.4 (±1.7), compared to 3.1 (±2.3) using the conventional ropeladder technique. Although without reaching a statistically significant difference, diminished pain was associated with the buttonhole technique.  相似文献   
992.
背景FIZZ1是一个与炎症相关的有丝分裂因子,具有刺激肺动脉平滑肌增殖、收缩血管、促进血管新生等作用。我们曾经报道FIZZ1在动脉粥样硬化中的作用,但对其作用机制尚未进一步探讨。目的探讨FIZZ1对氧化低密度脂蛋白(ox-LDL)诱导的小鼠平滑肌细胞清道夫受体A(SR-A)表达的影响。方法用ox-LDL以及终浓度分别为3×10-6、9×10-6、2.7×10-5mmol/L的FIZZ1刺激培养的平滑肌细胞,激光共聚焦显微镜对SR-A表达进行定位,流式细胞术检测不同剂量的重组FIZZ1对ox-LDL诱导的平滑肌细胞SR-A表达的影响。结果ox-LDL能诱导平滑肌细胞SR-A表达,SR-A表达主要位于细胞膜,重组FIZZ1能明显剂量相关地促进ox-LDL诱导的平滑肌细胞SR-A表达(与对照组比较,P<0.01)。结论FIZZ1明显促进ox-LDL诱导的平滑肌细胞SR-A表达,提示FIZZ1可能通过促进平滑肌细胞SR-A表达促进动脉粥样硬化进展。  相似文献   
993.
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995.
目的 探讨乙醇对大鼠血管内皮细胞的促凋亡作用.方法 乙醇灌胃制备大鼠实验模型,选用平铺内皮细胞,苏木素-伊红染色染色、末端脱氧核苷酸转移酶介导的-生物素平移末端标记和分光光度法了解乙醇对大鼠血管内皮细胞的促凋亡作用.结果 正常对照组未见凋亡细胞,而实验各组均可见凋亡细胞,其凋亡率有时间依赖性;实验各组血清中丙二醛含量显著增加和总抗氧化能力显著降低,其值具有时间依赖性.结论 过量乙醇使体内氧化-抗氧化系统严重失衡可导致内皮细胞凋亡.  相似文献   
996.
Jeffcoate W 《Diabetologia》2004,47(9):1488-1492
Diabetic neuropathy is associated with osteopenia and calcification of vascular smooth muscle cells. These changes are most marked in patients with acute neuropathic osteoarthropathy (Charcot foot), in which osteopenia is universal and the prevalence of vascular calcification exceeds 90%. While it has been thought that both osteopenia and vascular calcification may be linked to sympathetic denervation with increased peripheral limb perfusion, the cellular mechanism was not clear. However, the recent recognition that the receptor activator of nuclear factor kappa B ligand (RANK-L)/osteoprotegerin (OPG) signalling pathway is central to the processes regulating bone turnover in a wide variety of medical conditions has raised the possibility that the same cytokines may be involved in the osteolysis which accompanies diabetic neuropathy. This is made more likely by the realisation that the RANK-L/OPG pathway is also thought to mediate the calcification of vascular smooth muscle cells in coronary and peripheral vascular disease. The circumstantial evidence underpinning this hypothesis is reviewed here, and it is suggested that the unregulated activation of RANK-L-mediated effects on bone and arteries may be triggered by the loss of nerve-derived peptides, e.g. calcitonin gene-related peptide, which normally exert a moderating influence on the pathway.  相似文献   
997.
Strategic targets for the management of foot ulcers focus on reducing the incidence of amputation. While data on the incidence of amputation can be obtained relatively easily, the figures require very careful interpretation. Variation in the definition of amputation, population selection and the choice of numerator and denominator make comparisons difficult. Major and minor amputation have to be distinguished as they are undertaken for different reasons and are associated with different costs and functional implications. Many factors influence the decision of whether or not to remove a limb. In addition to disease severity, co-morbidities, and social and individual patient factors, many aspects of the structure of care services affect this decision, including access to primary care, quality of primary care, delays in referral, availability and quality of specialist resources, and prevailing medical opinion. It follows that a high incidence of amputation can reflect a higher disease prevalence, late referral, limited resources, or a particularly interventionist approach by a specialist team. Conversely, a low incidence of amputation can indicate a lower disease prevalence or severity, good management of diabetes in primary and secondary care, or a particularly conservative approach by an expert team. An inappropriately conservative approach could conceivably enhance suffering by condemning a person to months of incapacity before they die with an unhealed ulcer. The reported annual incidence of major amputation in industrialised countries ranges from 0.06 to 3.83 per 103 people at risk. Some centres have documented that the incidence is falling, but this is often from a baseline value that was unusually high. Other centres have reported that the incidence has not changed. The ultimate target is to achieve not only a decrease in incidence, but also a low overall incidence. This must be accompanied by improvements in morbidity, mortality, and patient function and mood.  相似文献   
998.
血管黏附蛋白-1(VAP-1)作为一个非经典的炎性反应诱导的内皮分子,在精尿病及其血管并发症的发生、发展中具有重要作用.其具有胰岛素样作用,更为重要的是它可以通过促进炎性反应细胞渗出、黏附,介导炎性反应因子转录增加以及毒性产物导致内皮损伤、晚期糖基化终末产物的积累,从而进一步加重精尿病血管病变.以VAP-1为治疗靶点,通过调节VAP-1及其氨基脲敏感的胺氧化酶的活性可能成为一种防治糖尿病及血管病变的新途径.  相似文献   
999.
为了探讨健脾祛痰化瘀方在抗氧化型低密度脂蛋白致动脉粥样硬化中对信号转导分子钙离子和蛋白激酶C的影响,分别以健脾祛痰化瘀方-沥水调脂胶囊含药血清(浓度分别为5%、10%和20%)、氧化型低密度脂蛋白(100mg/L)处理人脐静脉内皮细胞和人脐动脉平滑肌细胞,以流式细胞仪检测两种细胞胞质游离钙离子浓度,以液体闪烁仪检测平滑肌细胞胞膜蛋白激酶C活性。结果发现,沥水调脂胶囊含药血清对氧化型低密度脂蛋白引起的内皮细胞、平滑肌细胞胞质游离钙离子浓度升高及平滑肌细胞胞膜蛋白激酶C活性升高有明显的抑制作用,其中20%含药血清作用最为明显。结果提示,健脾祛痰化瘀方可能通过调节钙离子、蛋白激酶C两种信号传递分子的变化起抗氧化作用,进而抑制内皮细胞凋亡及平滑肌细胞增殖,达到阻止动脉粥样硬化发生的作用。  相似文献   
1000.
Patients with pulmonary tuberculosis develop pleural effusions with a high protein content. Pleural mesothelial adherens junctions promote mesothelial cell-cell adhesion and contribute to pleural integrity. In the present study we have investigated the effect of mycobacterium (BCG) on mesothelial cell adherens junction proteins and pleural permeability. BCG enhanced pleural mesothelial cell (PMC) release of vascular endothelial growth factor (VEGF), and decreased electrical resistance across the PMC monolayer. Neutralizing antibodies to VEGF significantly restored the drop in PMC electrical resistance caused by BCG. BCG infection down regulated -catenin (adherens junction protein) expression and caused increased permeability across confluent mesothelial monolayer. Our results suggest that in TB pleurisy, mycobacteria cause VEGF release from mesothelial cells and leads to protein exudation by altering mesothelial adherens junction proteins.  相似文献   
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