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11.
S. Sunano T. Shimada K. Moriyama K. Shimamura 《Clinical and experimental pharmacology & physiology》1990,17(6):413-425
1. The time courses of the relaxation, induced by removal of extracellular Ca2+, of K-depolarized mesenteric artery preparations from stroke prone spontaneously hypertensive rats (SHRSP) and Wistar-Kyoto rats (WKY) were compared. 2. The time course of the decline in extracellular Ca2+ was estimated from the time course of the relaxation and the concentration-response curve of K(+)-depolarized preparations to Ca2+. The time course of the decline in the intracellular free Ca2+ concentration was also estimated from the reported relation between Ca2+ concentration and the contraction of skinned vascular smooth muscle. 3. The time course of relaxation was exponential, the curve being made up of three components. The time course was slower in preparations from SHRSP, especially the first component of the relaxation curve. 4. The time courses of the decline in the intracellular and extracellular Ca2+ concentrations were also exponential, being made up of three components and were also slower in the preparation made from SHRSP. 5. The wall and muscle layer of the mesenteric arteries used in the present experiments were significantly thicker in the SHRSP preparations. 6. Calculation of the half relaxation time, based on the diffusion of Ca2+ across the blood vessel wall, suggested that the slower relaxation in preparations from SHRSP is due largely to the thicker muscle layer, although differences in Ca2+ sequestration by the smooth muscle cells may also be involved. 相似文献
12.
L. G. Krivoshchapov E. M. Pal'tseva 《Bulletin of experimental biology and medicine》1998,126(5):1160-1163
Methylprednisolone increased the content of laminine, cyclosporin increased the content of fibronectin, and cyclophosphamide
suppressed the extracellular matrix production in experimental nephrotoxic nephritis and puromycin aminonucleoside nephrosis.
Therapy should be chosen with due consideration of the extracellular matrix structure in different morphological variants
of chronic glomerulonephritis.
Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 126, No. 11, pp. 584–587, November, 1998 相似文献
13.
糖尿病大鼠肺病理改变及同期肾脏病理变化对比 总被引:3,自引:0,他引:3
目的:观察糖尿病(DM)大鼠肺组织改变及与同期肾脏变化的关系.方法:链脲菌素腹腔注射制作糖尿病大鼠模型,4周后胶原、网状纤维染色及透射电镜方法观察糖尿病大鼠肺组织基底膜病理改变,同期观察肾脏改变.结果:DM大鼠4周后肺组织病理改变为毛细血管基底膜及Ⅱ型肺泡上皮细胞基底膜不同程度的增厚及肺间质胶原成分等细胞外基质的增多,与同期糖尿病肾脏病变相平行.结论:DM大鼠4周后肺组织与糖尿病肾病相似,主要表现为微血管病变. 相似文献
14.
R. O. HYNES 《Journal of thrombosis and haemostasis》2007,5(S1):32-40
Summary. Vascular development requires correct interactions among endothelial cells, pericytes and surrounding cells. These interactions involve many cell adhesion interactions, including cell–matrix interactions both with basement membranes and with surrounding extracellular matrices. Investigations of the contributions of these various interactions in vascular development and angiogenesis have been rather uneven and incomplete over the past 10–15 years. There has been considerable concentration on a few receptors, matrix proteins and proteolytic fragments with the goal of finding means to control angiogenesis. Many other potential contributors have received much less attention. Even for those molecules that have been subject to intensive investigation, our knowledge is incomplete. This review will survey the spectrum of extracellular matrix (ECM) proteins and cell–matrix adhesion receptors (particularly integrins) that are likely to contribute to angiogenesis and discuss what is known and not known about the roles of each of them. 相似文献
15.
L.H. JASPARS E. BLOEMENA P. BONNET P. VAN DER VALK C.J.L.M. MEIJER 《Histopathology》1995,26(2):113-121
In this study the distribution patterns of various extracellular matrix components and their receptors (i.e. β1 integrins) in B-cell non-Hodgkin lymphomas were examined and compared to those in reactive lymphoid tissue. Neoplastic follicles within follicular lymphomas showed similar patterns to that observed in reactive follicles, which appeared to be strongly associated with the presence of follicular dendritic cells. Diffuse lymphomas of low and intermediate malignancy grade revealed features comparable to those of interfollicular areas of reactive lymphoid tissue, irrespective to which compartment the tumour cells were related. Highly malignant lymphomas, however, displayed unique extracellular matrix configurations, resulting from active matrix degradation by macrophages; this may support rapid tumour growth. Extranodal lymphomas showed virtually the same matrix patterns as their nodal counterparts, suggesting that (malignant) lymphoid cells generate (at least partly) their own specific microenvironment. In reactive lymphoid tissue β1 integrins were mainly found on resident cells and except for α4, α5 (and β1) the lymphoid cells expressed very little, if any, β1 integrins. In comparison, expression of these integrins on lymphoma cells was reduced (follicular lymphomas) or could not be detected at all (diffusely growing lymphomas); this might contribute to the growth pattern and metastatic properties of the tumours. 相似文献
16.
颅脑损伤患者伤后细胞免疫功能变化及黄芪的免疫调节作用 总被引:3,自引:0,他引:3
目的:研究颅脑损伤患者伤后细胞免疫功能的变化规律及黄芪对细胞免疫功能的调节作用。方法:73例中、重型颅脑损伤患者随机分为常规治疗组35例和黄芪治疗组38例。对照组10例。采用放射免疫法.双抗体夹心酶联免疫吸附法及碱性磷酸酶法于不同时间检测各组患者细胞免疫学指标,1个月后进行疗效评价,并进行统计学处理。结果:颅脑损伤患者伤后1d IL-2、CD4、CD4/CD8显著下降,SIL-2R及CD8显著升高(P<0.01)。伤后第30天常规组与黄芪组比较IL-2,SIL-2R,CD8、CD4/CD8有显著性差异,CD4无显著性差异。伤后1月两组患者感染发生率、GCS评分、日常生活能力比较有显著性差异(P<0.01)。结论:中、重型颅脑损伤息者伤后存在显著的细胞免疫功能抑制,黄芪可以改善患者细胞免疫功能状态,提高机体抗感染能力.改善预后。 相似文献
17.
以方格星虫(Sipunculus nudus)体壁和血液为试验材料,经胰蛋白酶水解,Sevage法去除蛋白质,乙醇沉淀得到粗多糖,透析并冷冻干燥后分别得到方格星虫体壁多糖(SWP)和血液多糖(SBP)。经凝胶渗透色谱分析,SWP和SBP均为单一组分,相对分子质量分别为284528和198212。红外光谱分析表明,两种多耱结构相似,不含硫酸基团,均含有葡萄耱、半乳糖、木糖和阿拉伯糖。SBP含有乙酰氨基,而SWP不含乙酰氨基,它们是以α-糖苷键或β-糖苷键连接的呋喃多糖。 相似文献
18.
A Comparative Study on the Effect of BCG-PSN and Thymopeptides on T-lymphocyte Subsets of Normal and Immunosuppressed Mice 总被引:2,自引:0,他引:2
Polysaccharidenucleicacidfractionofbacilluscalmetteguerin (BCG PSN ,SiqikangInjection)andthymopeptidesarenowtwowidelyusedimmunomod ulatorsinclinicalpractice .Theyareusuallyusedasanadjuvanttherapyforvirusinfection ,autoimmunediseasesandneoplasms ,whichhavebeenclinicallyprovedtobeeffective .Somereportsdemonstratedthattheybothcanstimulatetheproliferationanddif ferentiationofT lymphocytes.However ,theexactmechanismshavenotbeenelucidatedyet .InordertocomparetheirmodulatingmechanismsonT lympho c… 相似文献
19.
目的 :探讨Erk信号传导通路调控乙醛刺激的肝星状细胞 (HSC)Na /Ca2 泵mRNA表达的影响。方法 :用链霉蛋白酶和胶原酶原位灌流 ,Metrizamide密度梯度离心分离大鼠肝星状细胞 ,采用RT PCR测定PD980 5 9阻断乙醛激活的肝星状细胞Erk活性后Na /Ca2 泵mRNA表达。结果 :乙醛刺激后 ,HSC后明显促进Na /Ca2 泵mRNA表达 (P<0 0 1) ,不同剂量PD980 5 9对肝星状细胞Na /Ca2 泵mRNA表达的影响无统计学意义。结论 :Erk信号传导通路可能对乙醛刺激的肝星状细胞激活状态的启动无明显影响 相似文献
20.
肝纤维化组织中MMP1、TIMP1的表达及其临床意义 总被引:2,自引:1,他引:1
目的 :检测肝纤维化组织中基质金属蛋白酶 1 (MMP1 )、基质金属蛋白酶组织抑制因子 1 (TIMP1 )的表达 ,为肝纤维化的诊治提供重要的分子生物学指标。 方法 :采用链霉菌抗生物蛋白 -过氧化酶联接法 (S- P法 )检测70例肝纤维化组织中 MMP1 、TIMP1 的表达。结果:(1) TIMP1 蛋白阳性表达随肝纤维化程度的加重而增强 ,并且呈正相关关系 (r=0 .92 74 ,P <0 .0 1)。 (2 ) MMP1 蛋白阳性表达随肝纤维化程度的加重无明显变化 ,无相关关系(r =0 .2 181,P >0 .0 5 )。 结论:TIMP1 与肝纤维化的发生、发展密切相关 ,随纤维化发生、发展阳性表达增强。从分子水平对肝纤维化、肝硬化病变进行评估 ,为早期诊治肝纤维化和判断预后提供依据。 相似文献