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101.
勃起功能障碍与血管内皮功能关系的研究进展 总被引:4,自引:2,他引:2
血管内皮功能在阴茎勃起过程中扮演了十分重要的角色,血管内皮功能障碍是ED的病理基础之一。测量肱动脉血流介导的血管扩张功能是目前血管内皮功能主要的评估方法。改善血管内皮功能的治疗能改善阴茎勃起功能。ED是心血管疾病的先兆,及早发现ED并给予适当治疗,在改善生活质量的同时有助于降低未来心血管疾病的风险。 相似文献
102.
目的研究重组人生长激素(rhGH)对生长激素受体(GHR)不同表达状态裸鼠人胃癌移植瘤生长及血管内皮生长因子(VEGF)表达的影响。方法采用免疫细胞化学染色法筛选出GHR阳性和阴性表达的细胞株各1株,分别接种于24只裸鼠皮下。将两种细胞接种裸鼠均随机分为对照组(0.9%NaCl,0.2ml/d)、低剂量rhGH组(0.5U·kg^-1·d^-1,0.2ml/d)和高剂量rhGH组(2.5U·kg^-1·d^-1,0.2mL/d)3组,每组8只,各组均连续给药14d,观察并记录裸鼠体重和肿瘤体积变化;采用酶联免疫吸附法测定各组裸鼠血清VEGF含量,免疫组织化学方法检测胃癌组织中VEGF蛋白表达,RT-PCR方法检测胃癌组织VEGFmRNA水平变化。结果筛选出GHR阳性表达的人胃癌细胞株SGC-7901和阴性表达的MKN-45。对于GHR^+SGC-7901接种裸鼠,rhGH给药组皮下移植瘤体积较对照组增大(P〈0.05),且高剂量rhGH组促增长效应最为显著(P〈0.05),3组间体重差异无统计学意义(P〉0.05);高剂量rhGH组的血清VEGF浓度为(252.94±15.32)ng/L,明显高于对照组的(49.94±5.73)ng/L和低剂量rhGH组的(167.60±9.54)ng/L(P〈0.05);对照组VEGF表达为中度阳性,rhGH给药组呈强阳性;高剂量rhGH组肿瘤组织中VEGFmRNA相对表达量为0.6470±0.0447,明显高于对照组的0.3230±0.0258和低剂量rhGH组的0.4120±0.0351(P〈0.05)。对于GHR—MKN-45接种裸鼠,rhGH给药组体重明显大于对照组(P〈0.05);肿瘤体积大小、血清VEGF水平、肿瘤组织VEGF蛋白及mRNA表达,3组间差异均无统计学意义(P〉0.05)。结论rhGH能促进GHR阳性表达的SGC-7901移植瘤生长,并促进VEGF表达增高;对于GHR阴性的MKN-45移植瘤,则没有表现出明显的促肿瘤生长及促VEGF表达效应。GHR存在可能是rhGH影响VEGF分泌的关键靶点。 相似文献
103.
Objective To investigate the inhibitory effects of fms-like typrosine kinase receptor sFh-1 on retinal neovascularization (RNV). Methods Recombinant lentivirus sFh-1 ( 2-3 ) and sFh-1 ( 2-4 )expressing the sFh-1 (2-3) and (2-4) immunoglobulin-like regions of sFh-1 were constructed. 96 seven-dayold C57/6J mice were randomly divided into 4 groups with 24 mice in each group. Group 1 : normal control;group 2: experimental control; group 3: sFlt-1(2-3); group 4: sFlt-1(2-4). The mice in group 2-4 were exposed to hyperoxia with (75±2)% O2 for 5 days and then returned to normoxia with 21% O2 ; the mice 相似文献
104.
Expression and distribution of vascular endothelial growth factor protein in human brain tumors 总被引:9,自引:0,他引:9
T. Pietsch Markus M. Valter Helmut K. Wolf A. von Deimling H.-J. Su Huang Webster K. Cavenee Otmar D. Wiestler 《Acta neuropathologica》1997,93(2):109-117
Marked neovascularization is a hallmark of many neoplasms in the nervous system. Recent reports indicate that the endothelial
mitogen vascular endothelial growth factor (VEGF) may play a critical role in the regulation of vascular endothelial proliferation
in malignant gliomas. Using novel monoclonal antibodies to the VEGF polypeptide we have determined the expression and cellular
distribution of VEGF protein in a representative series of 171 human central nervous system (CNS) tumors by immunohistochemistry
and immunoblotting. In agreement with previous in situ hybridization data, 19 out of 20 glioblastomas (95%) showed immunoreactivity
for VEGF, whereas both the percentage of immunoreactive tumors and the extent of immunoreactivity for VEGF were significantly
lower in astrocytomas. Of the pilocytic astrocytomas (WHO grade I) 44% were immunoreactive for VEGF, but we observed several
cases with pronounced vascular proliferates in the absence of VEGF. In ependymomas, meningiomas, hemangioblastomas, and primitive
neuroectodermal tumors, there was no correlation between VEGF expression, vascular endothelial proliferation and the grade
of malignancy. Oligodendrogliomas and the oligodendroglial component of mixed gliomas lacked immunoreactive VEGF, indicating
that endothelial growth factors other than VEGF may regulate tumor angiogenesis in these neoplasms. Western blot analysis
showed a predominant VEGF protein species of 23 kDa and confirmed the immunohistochemical data in all cases. Our findings
demonstrate that VEGF is expressed in a wide spectrum of brain tumors in which it may induce neovascularization. However,
other angiogenic factors also appear to contribute to the vascularization of CNS neoplasms.
Received: 18 April 1996 / Revised, accepted: 20 August 1996 相似文献
105.
在Langedorff离体大鼠心脏模型上比较了去冠脉内皮(实验组)和保留冠脉内皮(对照组)的心肌再灌注损伤。结果:实验组的左室峰值和最大升降速度、心肌超氧化物歧化酶及ATPase活性明显高于对照组(P<0.05),而冠脉灌注压和冠脉流出液中乳酸脱氢酶及磷酸肌酸激酶、心肌过氧化产物丙二醛则明显低于对照组(P<0.05)。表明:去冠脉内皮可减轻心肌再灌注损伤。提示:冠脉内皮细胞在心肌再灌注损伤中起重要作用。 相似文献
106.
107.
The Inhibitory Effect of Radix Salviae Miltiorrhizae on Hypoxic Structural Remodeling of Intra-acinarPulmonary Arteries 总被引:1,自引:0,他引:1
(席思川)(车东媛)(张婉蓉)TheInhibitoryEffectofRadixSalviaeMiltiorrhizaeonHypoxicStructuralRemodelingofIntra-acinarPulmonaryArteries¥XISi-c... 相似文献
108.
Quantitative morphology of human glioblastoma multiforme microvessels: structural basis of blood-brain barrier defect 总被引:3,自引:0,他引:3
B. L. Coomberl P. A. Stewart K. Hayakawa C. L. Farrell R. F. Del Maestros 《Journal of neuro-oncology》1987,5(4):299-307
Summary Neoplastic invasion of the brain parenchyma results in a disruption of the ultrastructure of the blood vessel walls such that serum proteins extravasate into the surrounding tissue, resulting in cerebral edema. The structural changes involved are not well understood, since the pores through which serum constituents pass (permeability routes) in normal barrier vessels and in tumor vessels where the barrier is compromised, have not been extensively explored. In this study we investigate the ultrastructure of human brain microvessels in biopsied samples of control brain tissue and five glioblastoma multiforme tumors. Electron micrographs of a total of 78 vessels were analysed with computer assisted morphometry for ultrastructural evidence of permeability routes. Fenestrations in the endothelium were not seen. Pinocytotic vesicle number and arrangement did not differ significantly from that seen in control brain vessels. Interendothelial junctions with enlarged distensions (which may represent sections through transendothelial channels) were seen in some vessels from most tumors but not in control barrier vessels. In addition, large gaps in the endothelial layer were seen in less than two percent of tumor vessels. In conclusion, glioblastoma multiforme vessels in this study show subtle alterations in vessel morphology from that seen in controls. We suggest that the high vascular permeability and resultant brain edema seen in glioblastoma multiforme tumors is likely due to the presence of channels through interendothelial junctions, and rare but large breaks in the endothelial wall. 相似文献
109.
110.
辛伐他汀对CD40L介导的ECV-304细胞E选择素表达及粘附功能的影响 总被引:2,自引:0,他引:2
目的研究在人脐静脉内皮细胞中3-羟-3-甲基戊二酰辅酶A(HMG-CoA)还原酶对CD40/CD40L系统介导的粘附分子表达的影响,及对淋巴细胞与内皮细胞的粘附功能的影响。方法采用人脐静脉内皮细胞株ECV-304,CD40L干预,使之与其表面的CD40作用,用不同浓度辛伐他汀或辛伐他汀(5μmol.L-1)+甲羟戊酸干预,流式细胞术和RT-PCR检测干预前后E选择素(E-Selectin)的表达,流式细胞术检测CD40L介导的淋巴细胞与内皮细胞的粘附功能。结果不同浓度辛伐他汀可下调CD40L介导的E-Selectin的表达,并呈一定的剂量依赖性。甲羟戊酸(400μmol.L-1)抑制了辛伐他汀(5μmol.L-1)对E-Selectin表达的下调作用。辛伐他汀可降低CD40L介导的淋巴细胞与内皮细胞的粘附功能。结论他汀类药物的抗炎作用与抑制CD40-CD40L系统有关,其机制是通过抑制HMG-CoA还原酶而发挥作用的。 相似文献