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991.
目的 探讨caveolin-1参与肝细胞癌血管生成及影响血管通透性的作用机制.方法 构建肝癌细胞系HepG2裸鼠皮下移植瘤模型,局部注射编码重组可溶性caveolin-1蛋白的重组腺相关病毒载体rAAV-PEG-caveolin-1,观察其对肝癌细胞生长的抑制作用;通过肿瘤微血管密度(microvessel density,MVD)检测肿瘤新生血管的生成;Western blot检测脉管标志蛋白PECAM-1表达改变;FITC标记右旋糖苷测定肿瘤微血管通透性;放射强度测定法检测肝癌组织中eNOS活性,TUNEL法检测caveolin-1对肿瘤细胞的诱导凋亡效应.结果 rAAV-PEG-caveolin-1转染组治疗第14天后,移植瘤的瘤重较对照组和空载体转染组有不同程度的减小(P<O.05);免疫组化分析及Western blot结果显示rAAV-PEG-caveolin-1转染组较对照组及空载体组MVD及PECAM-1表达显著减少(P<0.05);FITC-右旋糖苷测定表明rAAV-PEG-caveolin-1可有效降低肿瘤微血管通透性;rAAV-PEG-caveolin-1转染组较对照组及空载体组eNOS活性明显下降(P<0.05);TUNEL分析显示rAAV-PEG-caveolin-1可诱导肿瘤细胞凋亡.结论 Caveolin-1是血管生成调节的关键分子,能显著抑制肿瘤新生血管的形成,并能有效降低肿瘤微血管的通透性.  相似文献   
992.
Objective To study the effect of tranilast on cyclosporine A (CsA)-induced epithelial-to-mesenchymal transition in human renal tubular epithelial cells, and investigate the mechanism of its antifibrotic effect. Methods Cultured HK-2 cells were divided into four groups: (1)In the control group, cells were treated without any medicine; (2) The cell were treated with CsA (4. 2μmol/L) for 72 h; (3) The cells were treated with a combination of CsA (4. 2 μmol/L) and tranilast (100μmol/L); (4) The cells were treated with tranilast (100 μmol/L) alone for 72 h.Morphological changes of the cells were assessed by phase-contrast microscopy. The immunofluorescence and Western blotting were adopted to detect the expression of E-cadherin, α-SMA and OPN mRNA and proteins respectively. Results Tranilast could markedly ameliorate the morphological changes of HK-2 cells stimulated by CsA. The irmmunofluorescence staining revealed the expression of E-cadherin was markedly decreased in HK-2 cells stimulated with CsA for 72 as compared with the control group, while the expression of α-SMA and OPN was significantly higher in CsA group than the control group. The expression of E-cadherin in the CsA + Tranilast group was higher than the CsA group, while the expression of α-SMA and OPN in the CsA + Tranilast group was lower than the CsA group. Western blotting showed that protein expression level of E-cadherin in CsA group was dramatically lower than that in the control group (P<0. 05), while that of α-SMA and OPN in CsA group was significantly higher than in the control group (P<0.05). The protein expression level of E-cadherin in HK-2 cells in the CsA + Tranilast group was markedly higher than in the CsA group (P<0.05), and that of α-SMA and OPN in CsA + Tranilast group was significantly lower than in the CsA group (P<0. 05). Conclusion Tranilast can block the CsA-induced epithelialto-mesenchymal transition in HK-2 cells probably by suppressing the expression of OPN.  相似文献   
993.
目的 比较颈胸椎前路和后路臂丛神经下干切断伤与根性撕脱伤诱发神经病理性疼痛大鼠术侧后足的痛行为学特征.方法 18只成年雌性SD大鼠随机接受右侧前路下干切断、前路及后路下干根性撕脱手术(每组6只),另外6只健康大鼠作为对照组.臂丛损伤术前及术后3、7、14和28 d,检测大鼠术侧后足的机械痛缩足阈值、冷刺激诱发痛评分及热刺激缩足潜伏期.结果 对照组与3个损伤组之间术前三项痛行为学指标的差异无统计学意义.与术前相比,前路切断伤组冷刺激诱发痛评分明显增高(P<0.01),机械痛缩足阈值及热刺激缩足潜伏期则无明显变化;前路及后路撕脱伤组术后各时间点机械痛缩足阈值均显著降低(P<0.01),冷刺激诱发痛评分均明显增高(P<0.01),而热刺激缩足潜伏期则无显著变化.与切断伤组相比,两撕脱伤组术后各时间点热刺激缩足潜伏期则无显著差异,而后足机械痛缩足阈值均显著降低(P<0.05),冷刺激诱发痛评分亦显著增高(P<0.01),这种痛行为学的变化可持续至28 d(最长观察期);两撕脱伤组间各痛行为学指标的差异无统计学意义.结论 大鼠前、后入路臂丛下干根性撕脱伤均可作为理想的神经病理性疼痛模型,而臂丛下干切断伤因致痛效果较差则不宜用作神经病理性痛模型.  相似文献   
994.
995.
996.
Objective To investigate the role of allicin on rat nature killer (NK) cell activity in vitro under acidic microenvironment, and its possible mechanism. Methods CD3- NKR-P1+ NK cells isolated from the rat spleen were cultured in the complete RPMI 1640 medium ( pH 5. 6, pH 6. 5, or pH 7. 2 respectively), and treated with allicin at final concentration of 30 mg/L. Enzyme linked immunosorbent assay (ELISA) was used to determine supernatant interferon (IFN)-γ levels. The percentage of NK cells proliferation and apopotosis was analyzed by flow cytometry. NK cell cytotoxicity toward YAC-1 tumor cells was detected by LDH release assay. Results Proliferation and cytotoxicity of NK cells were significantly suppressed by acidic microenvironment in vitro. Under the cultured condition of acidic pH below 7. 2, allicin seemed to promote NK cells proliferation, which reached to highest level of 33% at pH 5. 6 cultured for 16 h. Correspondingly, at pH of 5. 6, allicin induced a marked increase of IFN-γ concentration in the supernatant from (50. 07 ± 0. 38) (cultured for 4 h) to (64. 59 ± 0. 09) ng/L ( cultured for 16 h). The cytotoxicity of NK cells toward YAC-1 tumor cells was also found strongest under the condition of pH 5. 6 cultured for 16 h. Conclusion Allicin favored to enhance the cytotoxicity of NK cells under the acidic cultured condition, which might be related to the increase of IFN-γ production.  相似文献   
997.
Objective To investigate the prevalence and risk factors of chronic kidney disease (CKD) in the general adult population in the Hulunbeir Prefecture, Inner Mongolia Autonomous Region where many minorities of north China live. Methods Sampling surveywas performed in the residents aged 20 years and older in the Hulunbeir Prefecture. All the investigated subjects were tested for urinary albumin to creatinine ratio (ACR); hematuria by microscopy of urinary sediment; and GFR estimated by modified MDRD equation for Chinese adults (eGFR). The related risk factors of CKD were also investigated. Results A total of 4522 subjects were enrolled in the study. The prevalence of albuminuria was 7.11%, hematuria was 2.64% and reduced eGFR [60 ml-min-1·(1.73 m2)-1] was 2.75%. The prevalence of hypertension was 38.90%; hyperglycemia 6.61%; hyperlipidemia 2.72%; increased waist 24.79% and metabolic syndrome 15.02%. After the subjects with combined microalbuminuria, hematuria and reduced eGFR were excluded, the prevalence of CKD was 12.95%. Logistic regression analysis and stratified analysis showed increased age, increased waist, elevated systolic pressure, hyperglycemia,hypertriglyceridemia and metabolic syndrome were independently associated with albuminuria;increased age, elevated systolic pressure and hyperglycemia were independently associated with reduced eGFR; increased age was independently associated with hematuria. Conclusions The prevalence of adult CKD is 12.95% in the Hulunbeir Prefecture, Inner Mongolia Autonomous Region. Independent risk factors of CKD include increased age, increased waist, hypertension,abnormal blood glucose or lipid, and metabolic syndrome.  相似文献   
998.
Objective To investigate the expression of Foxo3a and p27kip1 in lumbar dorsal root ganglia (DRG) after injury of sciatic nerve in rats. Methods Adult rats were randomly divided into control group and experimental group. The rats in experimental group were subjected to sciatic nerve clamp.Expression and distribution of Foxo3a and p27kip1 and cellular proliferation and axon regeneration in DRG was detected by western blot and immunohistochemistry. Results Foxo3a protein levels begined to reduce at 1 day (7.0 ± 3.5), reached valley at 2 day (6.0 ± 3.8) after injury, and following Foxo3a downregulation, p27kip1 protein levels begined to decrease at 2 day (29.0 ± 3.5), reached valley at 7 day (21.0± 3.0) after injury. Down-regulation of Foxo3a and p27kip1 was expressed predominantly in neurons and glial cells by double immunolabelling. Foxo3a and p27kip1 were expressed in neurons [(37.8 ± 5.7)%, (43.3 ±4.3)%] and glial [(22.4 ± 3.9)%, (13.8 ± 3.2)%] cells in sections of DRG at 2 day after injury less than neurons [(73.6 ± 2.5)%, (84.1 ± 3.7)%] and glial [(61.3 ± 4.4)%, (68.7 ± 5.6)%] cells in sections of normal DRG. Proliferating cell nuclear antigen (PCNA) and GAP-43 were up-regulation from 2 day, and PCNA reached peak at 7 day after injury.The glial cells were the main type of cellular proliferation.Conclusion Down-regulation of Foxo3a and p27kip1 in lumbar DRG is correlated with the proliferation of glial cells and axonal regeneration after sciatic nerve injury.  相似文献   
999.
目的 评价隆乳术治疗先天乳腺不发育、乳腺发育不良及胸大肌发育不良伴轻度鸡胸畸形临床效果.方法 对10例先天乳腺不发育、乳腺发育不良及胸大肌发育不良伴轻度鸡胸的女性行隆乳术.先在体表标出剥离范围及畸形部位,经双腋窝切口,直达皮下组织,向内分离至胸大肌外侧缘,于胸大肌后间隙,置入硅凝胶乳房假体.结果 10例于隆乳术后,随访1年,均未见发生局部感染、假体移位、心肺功能异常等并发症,前胸壁鸡胸畸形外观有明显改善.结论 应用隆乳术治疗先天性乳腺不发育、乳腺发育不良及胸大肌发育不良并伴有轻度鸡胸,操作方便、手术损伤小、效果满意.既美化乳房外观又掩饰了鸡胸畸形,具有双重手术效果,值得推广.  相似文献   
1000.
目的 探讨采用预制颞顶筋膜瓣置入于残耳乳突区皮下进行扩张,观察以扩张的筋膜瓣覆盖多孔高密度聚乙烯(porous high density polyethylene,Medpor)支架做全耳廓再造术的方法 和效果.方法 30例先天性小耳畸形,手术分两期:Ⅰ期,设计带有颞浅动静脉顶支为血管蒂的预制岛状颞浅筋膜瓣,植入残耳侧乳突区皮下腔穴,然后置入皮肤扩张器进行同期同步扩张;Ⅱ期,将扩张的耳后筋膜皮瓣连带颞浅筋膜瓣掀起,覆盖于Medpor支架上,耳后创面中厚植皮,进行全耳廓再造术.结果 经6个月至3年的随访观察,再造耳廓外形逼真,皮色红润,与周围皮肤颜色无异,其大小、形状、位置与面部协调,与健耳对称,微细结构显示清晰.结论 选用Medpor支架,只要熟悉此材料的生物特性,选择合适的手术操作步骤要点,然后采用预制扩张的耳后筋膜皮瓣连带颞浅筋膜瓣覆盖支架,可将手术并发症减少到最低限度,具有创伤小、操作简单、疗程短、术后效果满意、可避免耳廓外形臃肿或支架外露等优点.耳后筋膜皮瓣与颞浅筋膜瓣两者结合,是目前较为理想的全耳廓再造的一种方法 .  相似文献   
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