首页 | 本学科首页   官方微博 | 高级检索  
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   26篇
  国内免费   2篇
  完全免费   9篇
  综合类   37篇
  2017年   4篇
  2016年   4篇
  2015年   2篇
  2013年   1篇
  2012年   5篇
  2011年   2篇
  2010年   7篇
  2009年   4篇
  2008年   3篇
  2007年   3篇
  2001年   1篇
  1996年   1篇
排序方式: 共有37条查询结果,搜索用时 46 毫秒
Background Nanobone putty is an injectable and bioresorbable bone substitute. The neutral-pH putty resembles hard bone tissue, does not contain polymers or plasticizers, and is self-setting and nearly isothermic, properties which are helpful for the adhesion, proliferation, and function of bone cells. The aim of this study was to investigate the osteogenic potential of human bone morphogenetic protein 2 (hBMP2) gene activated nanobone putty in inducing ectopic bone formation, and the effects of the hBMP2 gene activated nanobone putty on repairing bone defects.
Methods Twenty four Kunming mice were randomly divided into two groups. The nanobone putty + hBMP2 plasmid was injected into the right thigh muscle pouches of the mice (experiment side). The nanobone putty + blank plasmid or nanobone putty was injected into the left thigh muscle pouches of the group 1 (control side 1) or group 2 (control side 2), respectively. The effects of ectopic bone formation were evaluated by radiography, histology, and molecular biology analysis at 2 and 4 weeks after operation. Bilateral 15 mm radial defects were made in forty-eight rabbits. These rabbits were randomly divided into three groups: Group A, nanobone putty + hBMP2 plasmid; Group B, putty + blank plasmid; Group C, nanobone putty only. Six rabbits with left radial defects served as blank controls. The effect of bone repairing was evaluated by radiography, histology, molecular biology, and biomechanical analysis at 4, 8, and 12 weeks after operation.
Results The tissue from the experimental side of the mice expressed hBMP2. Obvious cartilage and island-distributed immature bone formation in implants of the experiment side were observed at 2 weeks after operation, and massive mature bone observed at 4 weeks. No bone formation was observed in the control side of the mice. The ALP activity in the experiment side of the mice was higher than that in the control side. The tissue of Group A rabbits expressed hBMP2 protein and higher ALP level. The ne  相似文献
目的:观察腺病毒介导的骨形态发生蛋白-2(BMP-2)基因转移对人间充质干细胞(hMSCs)成骨能力的影响。方法:从健康志愿者全骨髓中分离培养hMSCs,体外扩增纯化后随机分为4组。(1)Ad-BMP-2组:培养液中加入BMP-2基因重组腺病毒(Ad-BMP-2,1×1010OPU/mL)孵育24h;(2)Ad-LacZ组:培养液中加入半乳糖酐酶基因重组腺病毒(Ad-LacZ);(3)阳性对照组:培养液中添加地塞米松、抗坏血酸和β-甘油磷酸钠。(4)空白对照组。2w后行Von Kossa染色检测hMSCs中骨胶原结节形成;生化分析仪检测碱性磷酸酶(ALP)活性。结果:经多次换液传代,hMSCs呈均一梭形。Ad-BMP-2组与阳性对照组细胞形态逐渐趋于扁平,突起减少,VonKossa染可见大量红色骨胶原结节形成,ALP活性也显著增高。结论:Ad-BMP-2基因转染对hMSCs成骨能力具有促进作用。  相似文献
目的明确萎缩性骨不连组织水平表达上调的hsa-miR-654-5p在人骨髓基质干细胞(hBMSCs)中对其预测靶基因骨形态发生蛋白2(BMP2)mRNA和蛋白的抑制作用,探索其在成骨分化过程中的生物学调控功能。方法分离培养hBMSCs,将第4代hBMSCs培养16 h后分别按相应体系转染细胞,再培养48 h后取六孔板内细胞提取总RNA和总蛋白,进行实时定量PCR(qRT-PCR)和Western blotting,取24孔板内细胞进行双荧光素酶报告基因检测。结果当hBMSCs中hsa-miR-654-5p过表达时,BMP2的mRNA和蛋白表达水平均发生明显下调;双荧光素酶报告基因检测提示,BMP2的预测靶位点直接受hsa-miR-654-5p的抑制调控,该靶位点被突变后hsa-miR-654-5p对BMP2的抑制作用消失。结论 hsa-miR-654-5p可通过作用于BMP2的特定靶位点而直接抑制BMP2的mRNA和蛋白表达。hsa-miR-654-5p的变化在成骨分化调控过程中具有重要作用。  相似文献
Background Synovium-derived stem cells (SDSCs) with higher chondrogenic potential are attracting considerable attention as a cell source for cartilage regeneration. We investigated the effect of bone morphogenetic protein 2 (BMP-2) on transforming growth factor beta3 (TGF-β3)-induced chondrogenesis of SDSCs isolated from human osteoarthritic synovium in a pellet culture system. Methods The clonogenicity, stem cell marker expression and multi-differentiation potential of isolated SDSCs were determined by colony forming unit assay, flow cytometry and specific staining including alizarin red S, Oil red O and alcian blue staining, respectively. SDSCs pellet was cultured in chondrogenic medium with or without TGF-β3 or/and BMP-2. At day 21, the diameter and the weight of the pellets were measured. Chondrogenic differentiation of SDSCs was evaluated by Safranin O staining, immunohistochemical staining of collagen type Ⅱ, sulfated glycosaminoglycan (sGAG) synthesis and mRNA expression of collagen type Ⅱ, aggrecan, SOX9, link-protein, collagen type X and BMP receptor Ⅱ. Results Cells isolated under the optimized culturing density (104/60 cm2) showed clonogenicity and multi-differentiation potential. These cells were positive (〉99%) for CD44, CD90, CD105 and negative (〈10%) for CD34 and CD71. SDSCs differentiated to a chondrocytic phenotype in chondrogenic medium containing TGF-β3 with or without BMP-2. Safranin O staining of the extracellular matrix was positive and the expression of collagen type Ⅱ was detected. Cell pellets treated with TGF-β3 and BMP-2 were larger in diameter and weight, produced more sGAGs, and expressed higher levels of collagen type Ⅱ and other chondrogenic markers, except COL10A1, than medium with TGF-β3 alone. Conclusions SDSCs could be isolated from human osteoarthritic synovium. Supplementation with BMP-2 significantly promoted the in vitro TGF-β3-induced chondrogenic differentiation of SDSCs.  相似文献
目的克隆和构建人骨形成蛋白2(BMP-2)和人骨形成蛋白7(BMP-7)成熟肽真核表达载体。方法采用Trizol法从人骨肉瘤细胞中提取制备总RNA,利用RT-PCR、PCR转录、扩增BMP-2和BMP-7获得成熟肽基因,与真核表达载体pcDNA3.1(+)连接,构建真核表达重组子pcDNA3.1(+)/BMP-2MP和pcDNA3.1(+)/BMP-7MP。结果总RNA提取液电泳可见在28S、18S和5S处出现明显的条带,PCR和酶切可在439bp和364bp出现条带,阳性克隆测序结果与Genebank中登录的序列一致。结论成功克隆出人BMP-2MP和BMP-7MP基因,成熟肽基因已与pcDNA3.1(+)连接,成功构建其真核表达重组子pcDNA3.1/BMP-2MP和pcDNA3.1/BMP-7MP,为进一步研究BMP-2、BMP-7的功能及其成熟肽基因在骨髓间充质细胞(hMSCs)中表达以及在骨组织工程中的应用研究奠定了基础。  相似文献
梁俊 《医学综述》2010,16(15):2257-2259
牙齿发育初期和后期起调节作用的一些信号分子中,骨形成蛋白是与骨和牙齿形成相关的生长因子,作为形态生成信号在牙齿发育不同时期调控上皮与间充质间相互作用。牙胚发育过程中,BMP-2、BMP-4在牙胚发育各个时期的表达提示其在牙胚发育中的作用。研究表明,BMP-2、BMP-4作为上皮-间充质相互作用的继发调节信号参与牙齿发育,BMP-2参与调控牙乳头细胞分化形成成牙本质细胞;BMP-4与多种细胞因子相互作用参与调控牙型的形成。  相似文献
Human bone morphogenetic protein 2A (hBMP2A) cDNA terminal 567 nucleotides were cloned and expressed in a phage display vector pCSM2I. Hulnata BMP2A C-terminal peptide displayed on the surface of the phage can bind specifically to the sttrface of mouse osteoblastie cell (MC3T3) membrane. ELISA assay showed a positive signal of the binding by using antibody against M13 phage gene 8 protein. After labeling with ^3HTdR,the counts of the binding groups were 3 to 10 times higher than the control groups. It suggests that the‘surface of MC3T3 cells exist the recepzor for hBMP2A.  相似文献
R6SLnn Obetif Evaluer les effets de Wet de rkM sur as. mebo Faire la cul-ture Primaire de N et obServer les effets de dthentes concntrations de tal et de N sur laProlifdration de HPDLF, les activitis de Af, ta Syntha de I' osthalcine et Ia formtion des nduIesmithelifor. holfots W (5 -- 100ng/ml ) stimule de facon sghificative la Prolifhetion de HPtw.te activithe de Af sont nettement aewthe por 5ng/ml de tal. A 0, 5 -- 100ng/ml, tw n' a pesd' effet sur la optha de I' osMlcine et la f…  相似文献
目的 制备一种可长时间缓释骨形态发生蛋2(BMP-2)的聚己内酯(PCL)复合支架,并通过检测其对人源骨髓间充质于细胞(BMSC)成骨分化的影响探讨其在骨组织工程中的应用.方法 将磷脂(PL)和BMP-2混合形成的BMP-2/PL混合物(B/P)分散在二氯甲烷中,与PCL混合后,采用相分离法制备负载BMP-2的三维PCL-B/P复合支架和PCL-B传统支架,通过酶联免疫吸附试验(ELISA)检测两种支架的BMP-2缓释效果.将BMSC种植在PCL-B传统支架和PCL-B/P复合支架中,分别采用CCK-8法和实时定量PCR(qPCR)检测两种支架上BMSC的增殖和成骨分化能力.结果 与PCL-B传统支架对比,PCL-B/P复合支架对BMP-2缓释效果更佳,缓释时间更长,可达22 d.在BMSC培养的第7、14和21天,PCL-B/P复合支架上BMSC的增殖能力均优于PCL-B传统支架(P<0.05),且PCL-B/P复合支架上BMSC中碱性磷酸酶和Ⅰ型胶原蛋白、骨钙、骨桥蛋白3种成骨基因mRNA的表达均高于PCL-B传统支架(P<0.05,P<0.01).结论 成功地制备出一种可长时间缓释BMP-2的高分子三维PCL-B/P复合支架,其较PCL-B传统支架能更好地诱导BMSC的增殖和成骨分化.  相似文献
目的 探讨骨形态发生蛋白-2(bmp-2)和血管内皮生长因子165(vegf165)共表达基因修饰的骨髓间充质干细胞(BMSCs)对兔前交叉韧带重建术后腱骨界面的组织形态学和生物力学的影响.方法 将66只大白兔,随机分成实验组、对照组及正常组.实验组术后在腱骨界面注入经慢病毒转染稳定表达bmp-2和vegf165的BMSCs和纤维蛋白胶(FG),对照组腱骨界面注入BMSCs和FG,分别在术后第3、8和12周进行组织学观察和生物力学检测.结果 组织学病理显示,实验组新生血管和成纤维细胞浸润高于对照组,并在术后第12周形成典型的4层直接止点结构,其组织愈合情况优于同期对照组.生物力学显示相同时间点实验组最大载负荷明显高于对照组,差异有统计学意义(P<0.05).结论 bmp-2和vegf165共表达基因修饰的BMSCs对腱骨界面愈合有促进作用.  相似文献
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号