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81.
The skeletal extracellular matrix produced by osteoblasts contains the glycoprotein fibronectin (Fn), which regulates the adhesion, differentiation, and function of osteoblasts. Fn fibrillogenesis is involved in the process of bone mineralization. Bone morphogenetic proteins (BMPs) can be isolated from organic bone matrix and are able to initiate de novo cartilage and bone formation. In this study, the effect of BMP-4 on Fn fibrillogenesis in cultured rat osteoblasts was examined. BMP-4 enhanced Fn synthesis and extracellular Fn assembly in primary cultured osteoblasts. In addition, the extracellular assembly of Fn from exogenously applied soluble human Fn was also increased by BMP-4. It has been reported that alpha5beta1 integrin is related to Fn fibrillogenesis. The synthesis of both alpha5 and beta1 integrins was upregulated by BMP-4. Immunocytochemistry showed that the clustering of alpha5 and beta1 integrins was also increased by BMP-4. BMP-4 increased fibril formation of Fn and the adhesion of osteoblasts onto Fn matrix, which was inhibited by disintegrin triflavin and Gly-Arg-Gly-Asp-Ser (GRGDS) peptide. Phosphorylation of extracellular signal-regulated kinase (ERK) and focal adhesion kinase (FAK) was increased by BMP-4. Enhancement of extracellular Fn fibrillogenesis and the mRNA expression of beta1 integrin by BMP-4 were inhibited by ERK kinase (MEK) inhibitor PD98059. These results suggest that the enhancement of extracellular Fn fibrillogenesis by BMP-4 in cultured osteoblasts is related to the increase of the synthesis of Fn and clustering of alpha5 and beta1 integrins. ERK is involved in the signaling pathway of BMP-4 in regulating Fn fibrillogenesis in osteoblasts.  相似文献   
82.
烧伤大鼠血清对血管内皮细胞通透性的影响   总被引:4,自引:2,他引:2  
加深入阐明严重烧伤早期全身血管通透性增加继而引直民早期损害的发生机制,本实验应用培养于微孔滤膜上的小牛瞌 及皮细胞单层所构成的选择性通透屏障模型,观察了30%Ⅲ度烧伤大鼠血清对其影响,结果发现,烧伤早期烧伤血清刺激后EC单层对Hanks液或白蛋白液滤过流量、滤过系数均明显增加。  相似文献   
83.
We have advanced the hypothesis that the primary autolymphoproliferative response of dog T cells in mixed lymphocyte kidney cultures (MLKC) results from their recognition of tissue-specific (kidney-associated) antigen(s) presented in conjunction with class II MHC antigens. Lymphocyte culture-derived supernatants had been found previously to upregulate class II antigen expression on kidney cells and enhance T cell activation. In the present study we have isolated and characterized dog IFN-gamma, a class II-inducing substance that is secreted in the culture supernatant of activated T lymphocytes. Dog IFN-gamma was induced with A-23187 and PMA and purified stepwise using controlled-pore glass, Mono Q anion exchange chromatography, and Superose 6-gel filtration on FPLC. The purification resulted in two molecules of 42 Kd and 31 Kd molecular weights. An IgG1 monoclonal antibody was engendered to these molecules. With this mAb reagent, in immunochemical experiments, we have developed a sensitive ELISA and a method for purifying dog IFN-gamma by affinity chromatography. Species specificity studies indicated that purified dog IFN-gamma reacted with a polyclonal rabbit antihuman IFN-gamma, but not with a mAb to human IFN-gamma. However, the antidog IFN-gamma mAb that was generated also reacted with recombinant human IFN-gamma. In in vitro biological studies, the purified IFN-gamma (two mol. wt. species) upregulated the expression of canine class II MHC molecules on dog tubular epithelial cells and the dog kidney epithelial cell line (MDCK). The antidog IFN-gamma mAb blocked T cell proliferative response to kidney cell and, by inference, the interaction between endogenously released IFN-gamma in vitro with its cell surface receptor, thus inhibiting the induced upregulation of class II. Interestingly, although antidog IFN-gamma markedly blocked the MLKC (10 micrograms mAb/well), there was no effect on the allogeneic MLC. This observation indicates that the cytokine IFN-gamma may be a uniquely key substance amplifying the immune response of T cells to tissue-associated antigens on surrogate antigen-presenting cells that require induced upregulation of class II MHC antigen expression (MLKC), in contrast to reactions in which these antigens are already constitutively expressed on the antigen-presenting cells (mixed lymphocyte culture).  相似文献   
84.
More accurate noninvasive estimation of prostate size is important in therapeutic trials for benign prostatic hyperplasia. The accuracy of MRI and transrectal ultrasound (TRUS) in assessing prostate weight was evaluated in 48 patients who underwent radical prostatectomy for stage A or B cancer. The volume derived from the wet weight of the freshly excised specimen was used as a reference. We compared that volume with volume estimates derived from the three-axis linear dimension measurement by MRI and TRUS using a tissue density of 1.05 g/cc and the standard formula for an ellipsoid object. Prostate and seminal vesicle volumes were also computed by contouring T2-weighted 5 mm thick contiguous MR images using a semiautomatic edge detection program and pixel summation. Three-axis volume MRI method versus volume from wet weight has slightly less scatter than TRUS three-axis method (r = 0.85 vs r = 0.81). Contoured MR volume method has the least scatter r = 0.93, statistically better than the linear axis method. Contoured MRI volumetric analysis appears superior to linear MRI or TRUS methods in estimating true prostate volume.  相似文献   
85.
前列腺癌去雄激素治疗不良反应的预防和处理   总被引:1,自引:0,他引:1  
目的观察去雄激素治疗前列腺癌的不良反应,并探讨其预防和治疗。方法回顾性分析1998年7月-2006年1月112例去雄激素治疗晚期前列腺癌的临床资料。结果112例患者中,97例完成了不良反应的调查。随访3-36月,去雄激素治疗后潮热、性功能障碍、病理性骨折发生率分别为46%、75%、4%;患者潮热、精神疲乏、四肢乏力、纳差症状明显加重(P<0.05);性功能明显减退(P<0.05)。12例潮热症状严重者使用抗抑郁药博乐欣(25mg,tid)1-2周症状减轻。7例有骨转移性疼痛或严重骨质疏松患者,应用唑来膦酸4mg静脉滴注,每45d一次,骨痛症状缓解。结论去雄激素对前列腺癌患者生活质量有一定影响。博乐欣可减轻患者潮热症状,唑来膦酸可预防和治疗去雄激素相关的骨质疏松并发症。  相似文献   
86.
开放手术观察腰椎间盘突出症溶核失败45例分析   总被引:2,自引:2,他引:0  
目的 通过开放手术观察分析椎间盘髓核化学溶解术治疗腰椎间盘突出症失败原因。方法 收集溶核失败的腰椎间盘突出症45例行开放手术治疗。结果 术中见45例硬膜外脂肪完全消失,43例髓核未见溶解,2例髓核溶解呈糊状但未被吸收,21例伴有侧隐窝狭窄,15例突出物与神经根粘连,20例黄韧带增厚,2例椎管骨性狭窄,14例突出物钙化。结论 腰椎间盘突出症病变间隙合并有侧隐窝狭窄、神经根粘连、椎管狭窄、突出物钙化等,不是溶核治疗的适应证。  相似文献   
87.
前路减压Z-plate内固定治疗胸腰段爆裂性骨折伴不全性截瘫   总被引:11,自引:5,他引:6  
目的 探讨胸腰段爆裂性骨折伴不全瘫前路减压内固定优越性以及Z-plate系统的优点。方法 采用前路减压Z-plate内固定治疗胸腰段爆裂性骨折伴不全瘫25例。结果 全部病例均获随访,随访时间6~24个月,平均17个月。按Frankel分级评定有1~3级恢复,随访期间无后凸加重及内固定松动,植骨融合。结论 前路减压Z-plate内固定是治疗胸腰段爆裂性骨折的较好方法。  相似文献   
88.
Abstract Several statistical models that have been suggested in the periodontal literature for describing longitudinal attachment level changes, such as the gradual loss, single-burst, multiple-burst, and random walk models as well as other models introduced in this paper are compared by their power to predict future attachment loss. The data used in this analysis is from 1061 sites of 8 subjects, with moderate to severe periodontal disease, monitored monthly for about a year. This study found that none of the suggested models could significantly outperform the naive mean predictor, which predicts the future attachment level from the past mean. It was also found that no single model, such as the burst, gradual, or random walk, together with measurement error can fully explain the variation in the data. These results indicate that in the course of one year, the attachment level change may not follow the same model. Consequently, a model that fits well to past data cannot be accurately extended to the future.  相似文献   
89.
获得性纯红再障患者外周血T细胞亚群分析   总被引:7,自引:0,他引:7  
目的 本研究通过分析获得性纯红再障患者外周血T细胞亚群 ,进一步探讨该病的细胞免疫发病机制。方法 用抗人CD3、CD4、CD8、IFN γ及IL 4单抗结合人外周血单个核细胞 ,流式细胞术分析单个核细胞中CD3 +、CD4+、CD8+细胞数Th1、Th2、Tc1、Tc2细胞数以及CD4+/CD8+、Th1/Th2、Tc1/Tc2比值。结果 贫血组患者 ,外周血CD3 +细胞和CD8+细胞明显增加 (P <0 .0 1) ,CD4+/CD8+比例倒置 (P <0 .0 5 ) ;Tc2细胞明显增加 (P <0 .0 5 ) ,Tc1/Tc2比值降低(P <0 .0 5 ) ,治疗后血象恢复的患者各增高的亚群细胞均有所恢复 ,接近正常。结论 在获得性纯红再障患者T细胞明显增高 ,其中主要是CD8+细胞 ,而在CD8+细胞中 ,是Tc2细胞发挥了重要作用。经治疗有效的患者 ,其增高的T细胞亚群降低 ,提示以纠正病人细胞免疫异常为主的治疗方案有益于获得性纯红再障的治疗。  相似文献   
90.
目的 运用通瘀注射液在非直视下经输卵管盆腔给药对子宫内膜异位症 (EEMs)的治疗作用 ,探讨活血化瘀法对EEMs的作用机理及此给药法的优势。方法 将临床治疗的EEMs患者 60例随机分为治疗组 (通瘀注射液组 )和对照组 (丹那唑组 ) ,疗程各为 3个月。用药前后测定下列指标 :临床症状与体征、内分泌激素、血液流变学、癌抗原 12 5 (CA12 5)和子宫内膜抗体 (EMAb)的阳性率变化。结果 治疗组的临床症状与体征、血液粘滞度和红细胞压积、CA12 5和EMAb的阳性率均降低 ,卵泡刺激素 (FSH)、黄体生成素 (LH)、雌二醇 (E2 )和孕激素 (P)的含量均受到调节 ,与对照组相比 ,差异有显著性。而治疗组对内分泌的调节能力弱于对照组 ,但作用柔和、均衡。结论 通瘀注射液对EEMs的作用是通过清除月经时异位内膜的瘀血、水肿、改善微循环及组织供氧、调节免疫功能和内分泌紊乱而实现的 ,与丹那唑相比其副作用小、并以治本为主。盆腔给药法则可使药物直达病灶 ,见效快  相似文献   
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