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1.
背景:骨髓间充质干细胞的成脂肪分化与成骨分化比例的失衡与许多骨疾病密切相关,而近些年发现Wnt信号通路在调控骨髓间充质干细胞的分化方向中起重要作用.目的:通过Wnt信号通路PCR基因芯片观察大鼠骨髓间充质干细胞分化为脂肪细胞和成骨细胞后相关基因表达的变化,寻找Wnt信号通路中调控骨髓间充质干细胞分化的靶基因.方法:采用大鼠第3代骨髓间充质干细胞分别进行成骨诱导和成脂诱导,7 d后用Trizol萃取培养瓶中的细胞总RNA,倒置显微镜下观察骨髓间充质干细胞形态特征及成骨诱导后和成脂诱导后细胞形态特征.采用Wnt信号通路PCR芯片(大鼠)进行摹因芯片检测,以未诱导组为对照,计算成脂肪诱导,成骨诱导后相关基因上调/下调的比值.结果与结论:①倒置显微镜下观察,传3代后可获得均一性较高的骨髓间充质干细胞,骨髓间充质干细胞经成骨诱导后向成骨细胞方向分化,经成脂诱导后向脂肪细胞方向分化.②与未诱导组相比,骨髓间充质干细胞成脂诱导后Wnt信号通路表达上调的基因(Dkk-1,kremen,FZD1,FZD7)等15个(ratio>2),下调的基因(sFrp 5,β-catenin,Dvl3,Tcf7)等16个(ratio<0.5).成骨诱导后,Wnt信号通路表达上调的基因(Dkk1,kmmen,β-catenin,Wnt11)6个,表达下调的基因(sFrp5,sFRP4,Fzd1)等15个.提示WnI信号通路在骨髓间克质干细胞成脂细胞分化和成骨细胞分化中发挥重要作用.  相似文献   

2.
The efficacy of adiponectin (APN) in regulating bone metabolism remains controversial. This study aimed to investigate the role of APN secreted from adipose‐derived stem cells on adipogenesis and osteogenesis. Human APN gene was transfected via recombinant adenovirus into adipose derived stem cells (ASCs) in vitro and were cocultured with bone marrow mesenchymal stem cells (BMSCs) in using a transwell chamber. Adipogenesis was inhibited in APN‐transfected ASCs; in BMSCs, adipogenesis was inhibited, but osteogenesis was promoted in coculture with APN‐transfected ASCs. Next, the same adenovirus construct was transfected into the abdominal adipose tissue of a Sprague Dawley rat in vivo, and then a tibia defect was established in the same rat. We confirmed there was higher gene and protein expression of APN in ASCs and the abdominal adipose tissue of these rat models. Development of adipocytes in abdominal adipose tissue was suppressed, and less new bone was formed in the bone defect area. In conclusion, APN secreted from ASCs could directly inhibit adipogenesis in ASCs and BMSCs and promote osteogenesis in the latter. However, APN overexpression in adipose tissue was inversely associated with bone formation in tibia defects potentially due to decreased levels of circulating bone‐activating hormones.  相似文献   

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学术背景:骨髓间充质干细胞是具有多向分化能力的非造血多能干细胞,是细胞工程及基因治疗理想的靶细胞。 目的:综述骨髓间充质干细胞的生物学特性及其在组织修复中应用的研究进展。 检索策略:应用计算机检索PubMed 1997—01/2007—07期间相关文章,检索词为“mesenchymal stem cells,bone marrow,biological characterization,mesenchymal stemcells.bone marrow,tissue engineering”,并限定文章语言种类为English,同时检索中国期刊全文数据库2001—01/2007-03期间相关文章,检索词为“骨髓间充质干细胞,组织工程”。对资料进行初审,并查看每篇文献后的引文。纳入标准:文章所述内容应与骨髓问充质干细胞的生物学特性及其在组织修复中应用的研究进展相关。排除标准:重复研究或Meta分析类文章。共收集到313篇相关文献,26篇文献符合纳入标准,排除的287篇为内容陈旧或重复文献。 文献评价:从检索到的313篇文献中选择符合要求的相关文献26篇。符合纳入标准的26篇文献中,12篇涉及骨髓间充质干细胞的生物学特性,14篇涉及在组织修复中的研究进展。 资料综合:骨髓间充质干细胞主要存在于骨髓、软骨膜、骨膜、骨骼肌、骨小梁中,以骨髓组织中含量最为丰富。骨髓间充质干细胞具有多向分化潜能,在特定的条件下能向多种细胞系分化,具有向损伤局部集中的趋化性及“局部专一诱导性分化”、免疫调节、支持造血等生物学特性,目前已广泛应用于骨和软骨、心脏、皮肤、神经系统等多种组织修复的实验及临床研究,展现出良好的应用前景。 结论:随着对骨髓间充质干细胞研究、认识的深入,其在组织修复领域将有着广阔的临床应用前景。  相似文献   

5.
BackgroundThe stem cell niche in human bone marrow provides scaffolds, cellular frameworks and essential soluble cues to support the stemness of hematopoietic stem and progenitor cells (HSPCs). To decipher this complex structure and the corresponding cellular interactions, a number of in vitro model systems have been developed. The cellular microenvironment is of key importance, and mesenchymal stromal cells (MSCs) represent one of the major cellular determinants of the niche. Regulation of the self-renewal and differentiation of HSPCs requires not only direct cellular contact and adhesion molecules, but also various cytokines and chemokines. The C-X-C chemokine receptor type 4/stromal cell-derived factor 1 axis plays a pivotal role in stem cell mobilization and homing. As we have learned in recent years, to realistically simulate the physiological in vivo situation, advanced model systems should be based on niche cells arranged in a three-dimensional (3D) structure. By providing a dynamic rather than static setup, microbioreactor systems offer a number of advantages. In addition, the role of low oxygen tension in the niche microenvironment and its impact on hematopoietic stem cells need to be taken into account and are discussed in this review.SummaryThis review focuses on the role of MSCs as a part of the bone marrow niche, the interplay between MSCs and HSPCs and the most important regulatory factors that need to be considered when engineering artificial hematopoietic stem cell niche systems.ConclusionAdvanced 3D model systems using MSCs as niche cells and applying microbioreactor-based technology are capable of simulating the natural properties of the bone marrow niche more closely than ever before.  相似文献   

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Bone has the potential for spontaneous healing. This process, however, often fails in patients with comorbidities. Tissue engineering combining functional cells, biomaterials and osteoinductive cues may provide alternative treatment strategies. We have recently demonstrated that stromal cell‐derived factor‐1β (SDF‐1β) works in concert with bone morphogenetic protein‐2 (BMP‐2) to potentiate osteogenic differentiation of bone marrow‐derived mesenchymal stem/stromal cells (BMSCs). Here, we test the hypothesis that SDF‐1β overexpressed in Tet‐Off‐SDF‐1β BMSCs, delivered on acellular dermal matrix (ADM), synergistically augments BMP‐2‐induced healing of critical‐sized mouse calvarial defects. BMSC therapies alone showed limited bone healing, which was increased with co‐delivery of BMP‐2. This was further enhanced in Tet‐Off‐SDF‐1β BMSCs + BMP‐2. Only limited BMSC retention on ADM constructs was observed after 4 weeks in vivo, which was increased with BMP‐2 co‐delivery. In vitro cell proliferation studies showed that supplementing BMP‐2 to Tet‐Off BMSCs significantly increased the cell number during the first 24 h. Consequently, the increased cell numbers decreased the detectable BMP‐2 levels in the medium, but increased cell‐associated BMP‐2. The data suggest that SDF‐1β provides synergistic effects supporting BMP‐2‐induced, BMSC‐mediated bone formation and appears suitable for optimization of bone augmentation in combination therapy protocols. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   

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This article discusses the concept of a common stem cell for bone marrow stromal cells and haematopoietic cells. Until recently it was generally accepted that bone marrow contains two types of stem cells. One is the haemopoietic stem cell; the second one, the mesenchymal stem cell or stromal stem cell, gives rise to the stromal compartment of the marrow. The mesenchymal stem cells can differentiate into osteoblasts, chondroblasts, adipocytes, fibroblasts, and smooth muscle cells. Although the interplay between haemopoietic and stromal cells is well established, no transition of cells from the haemopoietic compartment into cells of the stromal compartment has been demonstrated. Recent data, based on grafting of genetically-marked haemopoietic cells points to the possibility of the generation of adipocytes from haemopoietic stem cells. These findings support the hypothesis postulating a common precursor cell for both bone and bone marrow.There is evidence that osteoblasts can differentiate into adipocytes, and that mesenchymal cells derived from subcutaneous adipose tissue can differentiate into osteogenic cells. The possibility of transdifferentiation of adipocytes into osteoblasts has also been demonstrated.  相似文献   

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骨髓基质干细胞治疗骨不连的新进展   总被引:1,自引:0,他引:1  
背景:骨髓基质干细胞体外培养增殖力强、易于向成骨细胞及软骨细胞方向分化且成骨性能稳定等特点,成为骨组织工程中合适的种子细胞.目的:总结分析采用骨髓基质干细胞作为种子细胞,分析其直接移植于骨不连部位或复合支架或转基因治疗骨不连所具有的优劣势.方法:检索1992/2011西文生物医学期刊文献数据及CNKI 数据库有关骨不连研究,骨髓基质干细胞分离、培养,在骨不连方面的应用,骨组织工程细胞支架方面的文献,英文检索词为"bone marrow stromal stem cells,nonunions,repairing,tissue engineering",中文检索词为"骨髓基质干细胞,骨修复,骨不连,组织工程".排除重复性研究,保留23篇进一步归纳总结.结果与结论:利用骨髓基质干细胞作为种子细胞,直接植入骨不连部位,或与适当的支架材料结合,或用骨髓基质干细胞作为靶细胞,导入外源目的基因诱导成骨的基因治疗来修复骨缺损的方法,给骨缺损的治疗带来光明的前景.但同时也存在骨髓基质干细胞增殖、分化合适条件难以准确确定,经皮移植自体骨髓基质干细胞植入体内后容易流失,不能在植入部位形成有效的细胞浓度,支架材料尚不能完全符合临床要求,以及如何将骨组织工程与基因治疗的方法结合起来等问题,需要进一步的研究.  相似文献   

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背景:骨折愈合与聚集在骨折端的骨髓间充质干细胞的数量及功能密切相关,基质细胞衍生因子1可增强骨髓间充质干细胞的趋化功能。目的:采用携带绿色荧光蛋白转基因骨髓间充质干细胞的骨髓嵌合体小鼠,制作左胫骨骨折模型,观察基质细胞衍生因子1对骨髓间充质细胞定向迁移的影响及其骨折修复中的作用,并初步探讨其作用机制。方法:利用密度梯度离心法从携带绿色荧光蛋白转基因小鼠C57BL的骨髓内分离培养出携带绿色荧光蛋白的骨髓间充质干细胞;将经X射线照射后携带绿色荧光蛋白转基因的骨髓间充质干细胞与雄性小鼠的骨髓非贴壁细胞联合移植,最后建立起稳定的骨髓嵌合型小鼠模型,再建立左胫骨骨折模型。建模后分别用基质细胞衍生因子1和基质细胞衍生因子1抗体干预,并设置对照组。结果与结论:建模后第1,3,7,14天各相应时相点骨折端的骨髓间充质干细胞数量,建模后第14,21天各相应时相点的骨痂量,建模后第28天抗折力,均为基质细胞衍生因子1组〉对照组〉基质细胞衍生因子1抗体组(P〈0.05);在建模后第28天基质细胞衍生因子1组骨痂量减少(P〈0.05),骨小梁融合成片,部分骨髓腔再通,对照组和基质细胞衍生因子1抗体组髓腔未通。证实,基质细胞衍生因子1可促进骨髓间充质干细胞向骨折端迁移,具有促进骨折愈合的作用。  相似文献   

10.
背景:如何提高牵张成骨过程中新骨形成的速度和质量,缩短牵张成骨治疗时间,减少并发症的发生是目前该领域的研究热点。目的:观察人骨形态发生蛋白2基因修饰自体骨髓间充质干细胞移植对兔下颌骨牵张成骨新骨形成的促进作用。方法:36只新西兰白兔随机摸球法分为3组。建立牵张成骨动物模型,在固定期第2天,实验组于牵张间隙注射人骨形态发生蛋白2基因修饰的自体骨髓间充质干细胞;对照组注射等量自体骨髓间充质干细胞;空白组注射等量生理盐水。结果与结论:在固定期2周及6周实验组牵张区骨小梁形成质量明显好于对照组和空白组。证实骨形态发生蛋白2基因修饰的自体骨髓间充质干细胞移植能有效促进兔下颌骨牵张成骨新骨形成。  相似文献   

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李杰  刘富顺 《中国临床康复》2012,(14):2617-2620
背景:骨髓基质干细胞移植是解决软骨组织缺损最有前景的手段之一,骨髓基质干细胞也成为软骨组织修复应用较广泛的重要种子细胞。目的:分析骨髓基质干细胞在半月板损伤和软骨损伤方面的应用情况,为膝关节半月板损伤的修复和治疗提供理论参考。方法:由第一、二作者共同检索1997/2011PubMed数据库及清华同方数据库,中文关键词为"骨髓间充质干细胞,膝关节半月板损伤",英文关键词为"bone marrow stromal cells;knee joint meniscus injury"。纳入骨髓基质干细胞修复膝关节半月板损伤的相关文献26篇进行分析。结果与结论:骨髓基质干细胞在治疗和修复膝关节半月板损伤方面具有独到的优势,包括其损伤面较小,方便易行,没有后遗症,并克服了切除半月板引起的形态和生物功能的改变,避免了因异体材料移植引起的膝载荷传导紊乱和晚期骨性关节炎发病的可能,与保留半月板修复其功能的临床治疗理念较为接近,并成为当前和今后治疗与修复膝关节半月板损伤的新思路。在其修复治疗的过程中,其关键问题在于一方面如何获得大量纯化的骨髓基质干细胞并在体外定向诱导为半月板软骨表型的细胞,另一方面是诱导分化的确切机制研究。  相似文献   

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背景:有研究显示表达CXCR4的干细胞能够沿着基质细胞衍生因子1的浓度梯度迁移到心肌梗死部位再生心肌和血管而改善心脏的功能。目的:探索间充质干细胞通过其分泌的基质细胞衍生因子1对心肌细胞的保护作用。方法:收集培养2d的间充质干细胞条件培养基。在缺氧条件,利用基质细胞衍生因子1受体CXCR4阻断剂AMD3100或P13.K/Akt途径阻断剂LY294002预处理H9C2细胞后,利用AnnexinV/PI双标法流式细胞术分析间充质干细胞条件培养基作用下H9C2细胞凋亡的变化;Western blotting分析H9C2细胞磷酸化Akt蛋白的表达;RT-PCR分析间充质干细胞基质细胞衍生因子1的表达。结果与结论:RT-PCR结果显示间充质干细胞表达基质细胞衍生因子1,Westernblotting结果显示间充质干细胞条件培养基增加了H9C2细胞磷酸化Akl蛋白的水平。AnnexinV/P1分析发现间充质干细胞条件培养基明显降低了H9C2细胞缺氧复氧后的凋亡,且这种抗凋亡作用能被CXCR4阻断剂AMD3100或P13-K/Akt途径阻断剂LY294002所阻断。说明间充质干细胞通过其分泌的基质细胞衍生因子1通过激活P13-K/Akt途径保护H9C2细胞,增加H9C2细胞的幸存能力。  相似文献   

13.
Substantial evidence has demonstrated that the decreased osteogenic differentiation of bone mesenchymal stem cells (BMSCs) is closely related to bone metabolic diseases. Thus, it is very important to develop several potentially useful therapeutic agents to enhance BMSC osteogenesis. Flavonoids show promise in enhancing bone mass. Dihydromyricetin (DMY), a type of flavonoid, has not yet been investigated regarding its effects on BMSC osteogenesis. To investigate the effects of DMY on osteogenesis, human BMSCs were induced with or without DMY. We found that DMY (0.1–50 μm ) exhibited no cytotoxic effect on proliferation, but increased alkaline phosphatase activity, osteoblast‐specific gene expression, and mineral deposition. It also enhanced active β‐catenin expression and reduced dickkopf‐1(DKK1) and sclerostin expression. The Wnt/β‐catenin signaling pathway inhibitor (DKK1 and β‐catenin‐specific siRNA) decreased the enhanced bone mineral formation caused by DMY. Taken together, these findings reveal that DMY enhances osteogenic differentiation of human BMSCs partly through Wnt/β‐catenin in vitro.  相似文献   

14.
背景:研究发现基质细胞衍生因子1除参与趋化干细胞定向迁移途径,还具有抗凋亡作用。目的:观察基质细胞衍生因子1预处理后对骨髓间充质干细胞凋亡的影响。方法:以不同浓度H2O2诱导大鼠骨髓间充质干细胞凋亡,取最适宜浓度100μmol/L用于实验。不同质量浓度基质细胞衍生因子1干预100μmol/L H2O2诱导后的大鼠骨髓间充质干细胞,选择0.2mg/L最佳保护质量浓度用于实验。取第3代大鼠骨髓间充质干细胞,随机分组:正常对照组不进行任何处理;损伤组在培养液中加入H2O2作用24h;基质细胞衍生因子1预处理组于H2O2损伤细胞前6h加入基质细胞衍生因子1;基质细胞衍生因子1+AMD3100(基质细胞衍生因子1受体CXCR4的阻断剂)组于H2O2细胞损伤前6h加入基质细胞衍生因子1与AMD3100共孵。结果与结论:H2O2能体外模拟缺血缺氧环境诱导骨髓间充质干细胞凋亡,且作用呈剂量依赖性。与损伤组比较,加入基质细胞衍生因子1预处理后细胞凋亡明显减轻(P<0.01),细胞E2F6基因表达增强(P<0.05),E2F1基因表达减少(P<0.05),线粒体细胞色素C转位减少(P<0.05),Caspase-3活性降低(P<0.05),AMD3100可阻断基质细胞衍生因子1对骨髓间充质干细胞的保护作用。提示基质细胞衍生因子1可能通过增强E2F6基因,负性调控E2F1基因抑制线粒体损伤导致的骨髓间充质干细胞凋亡。  相似文献   

15.
背景:再生障碍性贫血是T淋巴细胞免疫亢进破坏造血干祖细胞的一种异常免疫反应性疾病。骨髓间充质干细胞具有支持造血功能同时具有免疫调控作用。目的:观察骨髓间充质干细胞移植骨髓衰竭模型小鼠体内的归巢情况。方法:将BALB/c小鼠随机分成正常对照组、骨髓衰竭模型组和骨髓间充质干细胞移植组,于第6天将已标记氯甲基苯甲酰氨的BALB/c小鼠骨髓间充质干细胞经尾静脉注射途径移植给骨髓衰竭模型小鼠,采用流式细胞术和组织学荧光显微镜观察标记细胞在不同组织的动态分布。造模第14天,观察各组小鼠的平均生存时间、外周血血象和骨髓形态学特征。结果与结论:骨髓间充质干细胞经尾静脉输注后24h在受体小鼠骨髓中可发现氯甲基苯甲酰氨阳性标记细胞,72h时阳性标记细胞数量增多(P〈0.05)。骨髓间充质干细胞移植组小鼠濒死或处死前的白细胞、血红蛋白、血小板、骨髓单个核细胞数与模型组小鼠濒死时相比显著升高(P〈0.01)。骨髓衰竭模型组比骨髓间充质干细胞移植组平均生存时间短(P〈0.05)。结果证实,骨髓间充质干细胞输入骨髓衰竭模型体内能归巢至骨髓,促进造血恢复,减轻骨髓衰竭程度,显著延长生存时间。  相似文献   

16.
Myeloproliferative neoplasms (MPNs) are associated with significant alterations in the bone marrow microenvironment that include decreased expression of key niche factors and myelofibrosis. Here, we explored the contribution of TGF-β to these alterations by abrogating TGF-β signaling in bone marrow mesenchymal stromal cells. Loss of TGF-β signaling in Osx-Cre–targeted MSCs prevented the development of myelofibrosis in both MPLW515L and Jak2V617F models of MPNs. In contrast, despite the absence of myelofibrosis, loss of TGF-β signaling in mesenchymal stromal cells did not rescue the defective hematopoietic niche induced by MPLW515L, as evidenced by decreased bone marrow cellularity, hematopoietic stem/progenitor cell number, and Cxcl12 and Kitlg expression, and the presence of splenic extramedullary hematopoiesis. Induction of myelofibrosis by MPLW515L was intact in Osx-Cre Smad4fl/fl recipients, demonstrating that SMAD4-independent TGF-β signaling mediates the myelofibrosis phenotype. Indeed, treatment with a c-Jun N-terminal kinase (JNK) inhibitor prevented the development of myelofibrosis induced by MPLW515L. Together, these data show that JNK-dependent TGF-β signaling in mesenchymal stromal cells is responsible for the development of myelofibrosis but not hematopoietic niche disruption in MPNs, suggesting that the signals that regulate niche gene expression in bone marrow mesenchymal stromal cells are distinct from those that induce a fibrogenic program.  相似文献   

17.
目的:探讨冻干骨松质与转染有血管内皮细胞生长因子(VEGF)的骨髓基质干细胞(BMSC)能否在体内更有效地成骨。方法:采用新西兰大白兔BMSC体外培养扩增,然后用脂质体的方法将VEGF转染入该BMSC,再使其附着于同种异体冻干骨松质,并植入自体肌袋。8周后取标本进行苏木精-伊红染色、三色法染色观察。结果:8周时可见到转染有VEGF的BMSC复合冻干骨松质组在标本的表面有软骨和骨质形成,BMSC复合冻干骨松质组在标本的表面有成骨细胞、破骨细胞出现,并有类骨质形成,而单纯植入冻干骨松质组仅有大量纤维包裹。结论:转染有VEGF的BMSC复合冻干骨松质具有较好成骨活性,优于单纯BMSC复合冻干骨松质。  相似文献   

18.
About 40 years ago Friedenstein described stromal cells in the bone marrow that were spindle shaped and proliferate to form colonies. These cells attach to plastic and are able to differentiate under defined in vitro conditions into multiple cell types present in many different tissues, e.g. osteoblasts, chondroblasts, adipocytes, etc. Later on these cells, obtained from postnatal bone marrow, were called mesenchymal stem cells (MSC) or stromal stem cells. Recently the presence of somewhat similar cells has been demonstrated in many other tissues too. In spite of extensive attempts to characterize these cells we are still lacking definitive in vivo markers of MSC although retrospective functional data strongly support the existence of common adult stem cells that have the capacity to differentiate along various specific differentiation lineages. Since MSC can be rather easily isolated from the bone marrow and can also be expanded in vitro they have become a prime target for researchers of tissue regeneration. These cells have now been extensively used for transplantation experiments in animals and also for some therapeutic trials in humans. However, much new research is needed to learn enough on the molecular mechanisms of MSC differentiation to evaluate their full capacity for tissue regeneration.  相似文献   

19.
胎儿骨髓和肝脏间充质干细胞的表型和生物学性状研究   总被引:8,自引:3,他引:8  
为研究胎儿骨髓和肝脏间充质干细胞的表型和生物学性状,取胎龄为4-5个月水囊引产胎儿,将骨髓和肝脏细胞在SF(含2?S)培养基中培养,进行电镜观察,测定生长曲线,用流式细胞术对培养细胞进行表型测定。细胞周期分析。用SA方法测定Ⅰ,Ⅲ型胶原和vWF因子表达。结果表明;从胎儿骨髓和肝脏培养出的间充质干细胞,两在形态学,生长特性,免疫表型上是相似的,肝脏间充质干细胞有更好的支持造血的功能。结论提示,从胎儿骨髓和肝脏可分离培养出间充质干细胞。在体外有效扩增且保持其低分化状态。  相似文献   

20.
骨髓基质干细胞应用于软骨组织工程已近20年,这方面的研究也成为干细胞领域的研究热点.本文通过检索文献对骨髓间充质干细胞在软骨组织工程中应用的情况、取得的最新进展及面临的主要问题作一综述.随着分子生物学、生物材料学、计算机及纳米生物技术的发展,以骨髓间充质干细胞为种子细胞复合生物材料支架构建的组织工程软骨在修复关节软骨缺损中将具有广阔的应用前景.  相似文献   

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