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71.
目的 探讨碱性成纤维细胞生长因子 (b FGF)在低氧性肺动脉高压发病中的作用。方法 采用酶联免疫吸附法对具有低氧性肺动脉高压的肺心病患者 2 1例、无低氧性肺动脉高压的慢性阻塞性肺疾病 (COPD)患者 2 3例和 2 4例正常人血清 b FGF水平进行检测 ,以多普勒超声心动仪测定肺心病和 COPD患者的平均肺动脉压 (m PAP)。结果 肺心病组 m PAP水平 (33.33± 7.0 3m m Hg)明显高于 COPD组 (13.13± 2 .34mm Hg) ,P<0 .0 0 1;肺心病组血清 b FGF水平 (6 9.84± 16 .2 9pg/m l)明显高于 COPD组 (43.94± 7.5 7pg/ml)和正常对照组(44 .6 4± 6 .31pg/m l) ,P<0 .0 0 1;肺心病血清 b FGF水平与 m PAP之间呈明显正相关 ,r=0 .730 ,P<0 .0 0 1。结论慢性肺心病患者血清 b FGF水平明显升高 ,可能与其慢性低氧性肺动脉高压的形成有一定的关系。 相似文献
72.
Xiaoguang Chen Yi Li Lei Wang Mark Katakowski Lijie Zhang Jieli Chen Yongxian Xu Subhash C. Gautam Michael Chopp 《Neuropathology》2002,22(4):275-279
Intravenous administration of human bone marrow stromal cells (hMSCs) after middle cerebral artery occlusion (MCAo) in rats provides functional benefit. We tested the hypothesis that these functional benefits are derived in part from hMSC production of growth and trophic factors. Quantitative sandwich enzyme‐linked immunosorbent assay (ELISA) of hMSCs cultured with normal and MCAo brain extracts were performed. hMSCs cultured in supernatant derived from ischemic brain extracts increased production of brain‐derived neurotrophic factor (BDNF), nerve growth factor (NGF), vascular endothelial growth factor (VEGF) and hepatocyte growth factor (HGF). These neurotrophins and angiogenic growth factors increased in a post‐ischemia time‐dependent manner. The hMSC capacity to increase expression of growth and trophic factors may be the key to the benefit provided by transplanted hMSCs in the ischemic brain. 相似文献
73.
Enyioma N OBINECHE Michael PT GILLETT Abdishakur ABDULLE Mustapha SULAIMAN Mona AL-ROKHAIMI 《Nephrology (Carlton, Vic.)》2002,7(3):115-120
SUMMARY: In patients with chronic renal failure (CRF), hyperleptinaemia has been widely reported, but the exact mechanisms leading to elevated leptin levels are unclear. Impaired renal clearance of leptin and the influence of other hormones may be important. In this study, we measured serum leptin levels in 150 patients on haemodialysis, peritoneal dialysis or in the predialysis phase of CRF. Furthermore, we measured plasma levels of insulin, growth hormone (GH) and insulin-like growth factor 1 (IGF-1), as well as plasma levels of triacylglycerols and total low density lipoprotein (LDL)- and high density lipoprotein (HDL)-cholesterol. We observed significantly elevated levels of leptin, particularly in female patients, and leptin was shown to correlate significantly with insulin, total and LDL-cholesterol and log triacylglycerols. Leptin was inversely correlated with GH concentrations, but was not correlated with IGF-1 levels. Despite the multiple correlations established between leptin levels and other variables, only hyperinsulinaemia in CRF seems to be important as a determinator of leptin levels. 相似文献
74.
儿童髓母细胞瘤中VEGFR-2的表达 总被引:3,自引:0,他引:3
目的:探讨血管内皮生长因子受体VEGFR-2在儿童髓母细胞瘤中的表达及临床意义。方法:采用免疫组化LSAB法检测84例获随访的儿童髓母细胞瘤中的VEGFR-2表达,按术后生存期3,5,10年分为A,B,C三组,使用Cox回归统计分析。结果:84例儿童髓母细胞瘤中,VEGFR-2阳性表达74例(88.09%),A,B,C三组间VEGFR-2阳性表达分别为100%,88.89%,55.33%(P<0.01),Cox回归分析显示VEGFR-2是影响生存时间的一个独立的预后因子,它与预后存在负相关关系。结论:VEGFR-2表达水平可作为儿童髓母细胞瘤的预后指标之一。 相似文献
75.
目的 :观察天然碱性脂 (Stearylamine,SA)脂质体介导绿色荧光蛋白 /碱性成纤维细胞生长因子(GFP/bFGF)基因于不同时间段豚鼠耳蜗中的表达 ,为进一步研究耳聋的基因治疗提供实验基础。方法 :取豚鼠 1 6只 ,分成 4组 ,每组 4只。其中 3只右耳圆窗内注入SA -GFP/bFGF复合物 ,1只同法注入生理盐水作为对照。分别于术后第 2、7、1 4、2 1天取材。在荧光显微镜下观察GFP的表达 ,用免疫组化法检测bFGF的转导情况。结果 :荧光显微镜下见双侧耳蜗于术后第 2天开始部分细胞发出绿色荧光 ,第 7天达到高峰 ,支持细胞及内外毛细胞均显荧光 ,细胞轮廓清晰 ;第 1 4天开始减弱 ,第 2 1天消失。免疫组化染色显示 ,除血管纹外 ,耳蜗各回Corti器、螺旋韧带、螺旋缘及螺旋神经节细胞均有高浓度的表达产物 ,对照动物呈阴性表达。结论 :SA脂质体介导的GFP/bFGF基因单耳给药双侧耳蜗均有高效表达 ,为进一步研究基因治疗耳聋提供了可能。 相似文献
76.
血管内皮生长因子与乳腺癌临床病理因素及预后的关系 总被引:8,自引:0,他引:8
目的:探讨血管内皮生长因子在乳腺癌中的表达情况及其与预后的关系。方法:采用免疫组化法对1985年至1986年手术治疗的109例乳腺癌的原发灶进行血管内皮生长因子(VEGF)和微血管密度(MVD)检测,并与临床病理资料进行比较分析。结果:VEGF强表达组淋巴结转移率(52.2%)和病理分级明显高于弱表达且(23.5%,P<0.05);随VEGF表达强度的增加,生存率(5年、10年、15年)呈下降趋势,但无明显差异;VEGF与肿瘤大小、绝经状况、雌孕激素受体之间未见相关性。结论:VEGF表达与乳腺癌淋巴结转移和病理分级呈正相关,与预后呈负相关趋势,是估计恶性程度的有用指标,对判断预后有参考价值。 相似文献
77.
Nerve growth factor (NGF) and NGF receptors were measured in cortex and hippocampus of rats treated with drugs affecting cholinergic neurotransmission. High (Kd= 0.045nM) and low (Kd= 21nM) affinity125I-NGF binding sites were present in both cortical and hippocampal membranes with hippocampus containing higher numbers of both sites than cortex. Chronic treatment of rats with the muscarinic receptor antagonist scopolamine (5 mg/kg, twice daily) decreased the density of high- and low-affinity sites by 50–90% in cortical and hippocampal membranes. These changes were seen after 7 days, but not 3 days, of scopolamine treatment. Chronic infusion of physostigmine (1 mg/kg/day) using minipumps increased the number of high- and low-affinity sites in cortex 3- and 6-fold, respectively. The changes in receptor-binding parameters induced by physostigmine were transient as they were evident after 3 days of treatment, but returned to control levels after 7 days. NGF content in cortex and hippocampus was reduced by about 50% following 7, but not 3, days of chronic physostigmine infusion. In contrast, scopolamine treatment failed to change NGF levels in the cholinergic neuronal target regions but it decreased NGF content in the septal area. The content of NGF mRNA in the cortex measured by Northern blot analysis failed to change following either scopolamine or physostigmine treatment. The results suggest that levels of NGF and NGF receptors in the target regions of cholinergic neurons are regulated by the extent of cholinergic neurotransmitter activity. 相似文献
78.
目的 在体观察重组人血小板源性生长因子(recombinant human platelet—derived growth factor,rhPDGF)促进糖尿病大鼠全层皮肤缺损创面修复可能涉及的细胞和分子机制,研究其可能涉及的信号通路。方法 26只糖尿病大鼠,每只动物背部制备4个全层皮肤缺损创面,选取其中52个创面,随机分成3组,即对照组,创面自然愈合;rhPDGF治疗组,创面rhPDGF用量为7.0μg/cm^2;赋形剂组,创面用等量赋形剂凝胶。观察治疗后3、7和14d创面肉芽形成、胶原沉积、再上皮化速率以及炎性细胞浸润情况,并采用免疫荧光和免疫组织化学技术观察创面周围和创面修复细胞内细胞外信号调节激酶1/2(extracellular signal—regulated kinase1/2,ERK1/2)磷酸化和增殖细胞核抗原(proliferative cell nuclear antigen,PCNA)的表达。结果 组织学观察,rhPDGF治疗组创面可见大量炎性细胞浸润,毛细血管胚芽及成纤维细胞明显多于另两组(P〈0.05);胶原沉积明显,肉芽组织生长活跃,创面收缩显著,与对照组比较差异有统计学意义(P〈0.05)。免疫学研究显示,应用rhPDGF7~14d后,rhPDGF治疗组ERK1/2明显强于对照组和赋形剂组(P〈0.05);且损伤后3~7d rhPDGF治疗组修复细胞PCNA的表达明显高于对照组和赋形剂组(P〈0.05)。结论 rhPDGF促糖尿病大鼠刨面愈合的作用部分是通过ERK1/2信号通路的磷酸化来完成的。 相似文献
79.
表皮生长因子受体抑制剂AG1478对乳腺癌裸鼠移植瘤的生长影响 总被引:1,自引:0,他引:1
目的 观察表皮生长因子受体抑制剂AG1478和内分泌治疗联合应用对乳腺癌荷瘤裸鼠移植瘤生长的影响.方法 应用MCF-7乳腺癌细胞建立裸鼠动物模型,当肿瘤体积在100~200 mm3时,按肿瘤体积大小将裸鼠随机分成溶剂对照组、AG1478组、三苯氧胺(TAM)组、AG1478+TAM组,分别给予空白溶剂、AG1478腹腔注射、TAM灌胃、AG1478腹腔注射和TAM灌胃.同时给药6周,动态观察移植瘤生长,用药结束后2d处死裸鼠,取肿瘤称重、计算肿瘤体积(V=长径×短径2×π/6)、抑瘤率([(V对照组-V实验组)/V对照组]×100%).结果 各组裸鼠体重和肿瘤体积在治疗前具有均衡性.用药期间,溶剂对照组肿瘤生长最快,AGl478组次之,TAM组肿瘤生长较缓慢,而AGl478+TAM组肿瘤有缩小趋势.用药结束后,各组的抑瘤率分别为AG1478组30.4%,TAM组62%,AG1478+TAM组84.8%,与对照组比较差异有统计学意义(P<0.05).结论 AG1478对乳腺癌裸鼠移植瘤具有抑制作用,也可以加强三苯氧胺的抑瘤效果,两者有明显协同作用. 相似文献
80.
A Nofal I Al-Makhzangy E Attwa A Nassar A Abdalmoati 《Journal of the European Academy of Dermatology and Venereology》2009,23(7):803-806
Background Psoriasis is a chronic disease characterized by abnormal epidermal proliferation, inflammation and angiogenesis. It has been reported that vascular endothelial growth factor (VEGF) is overexpressed in lesional psoriatic skin and its serum levels are significantly elevated in patients with moderate to severe disease.
Objective This study aims to evaluate the possible role of VEGF in the pathogenesis of psoriasis, and its significance as an indicator of disease severity and control.
Methods Thirty patients with moderate to severe psoriasis and 10 healthy controls were subjected to baseline evaluation of VEGF. Patients were divided into three groups according to the received treatment: psoralen plus ultraviolet A (PUVA) thrice weekly (group 1), acitretin 50 mg daily (group 2), and combined PUVA twice weekly and acitretin 25 mg daily (group 3).Treatment continued for 16 weeks or up to clinical cure. Every patient was subjected to severity evaluation by Psoriasis Area and Severity Index (PASI) and measurement of serum VEGF before and after treatment.
Results Mean serum levels of VEGF were significantly elevated in patients (327 ± 66.2 pg/mL) than control subjects (178 ± 83.4 pg/mL). A highly significant correlation was found between VEGF and PASI score, but not with other variables. The best clinical response, the least side-effects and the highest reduction of VEGF serum levels were achieved by the combined therapy.
Conclusion The present study supported the proposed role of VEGF in the pathogenesis of psoriasis, and suggested that it could serve as a good indicator of disease severity and control. 相似文献
Objective This study aims to evaluate the possible role of VEGF in the pathogenesis of psoriasis, and its significance as an indicator of disease severity and control.
Methods Thirty patients with moderate to severe psoriasis and 10 healthy controls were subjected to baseline evaluation of VEGF. Patients were divided into three groups according to the received treatment: psoralen plus ultraviolet A (PUVA) thrice weekly (group 1), acitretin 50 mg daily (group 2), and combined PUVA twice weekly and acitretin 25 mg daily (group 3).Treatment continued for 16 weeks or up to clinical cure. Every patient was subjected to severity evaluation by Psoriasis Area and Severity Index (PASI) and measurement of serum VEGF before and after treatment.
Results Mean serum levels of VEGF were significantly elevated in patients (327 ± 66.2 pg/mL) than control subjects (178 ± 83.4 pg/mL). A highly significant correlation was found between VEGF and PASI score, but not with other variables. The best clinical response, the least side-effects and the highest reduction of VEGF serum levels were achieved by the combined therapy.
Conclusion The present study supported the proposed role of VEGF in the pathogenesis of psoriasis, and suggested that it could serve as a good indicator of disease severity and control. 相似文献