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背景:研究证实,力学因素可调控、诱导骨髓间充质干细胞定向分化为骨细胞,提高分化效率。 目的:观察振动应力刺激对兔骨缺损微环境中骨髓间充质干细胞移植修复肱骨骨缺损成骨分化能力的影响。 方法:24只兔按随机数字表法分为非振动单纯骨基质明胶组、非振动骨基质明胶+骨髓间充质干细胞复合植入组、振动骨基质明胶+骨髓间充质干细胞复合植入组,每组8只,建立兔肱骨骨缺损模型。振动组兔置于振动平台,以0.3 G的加速度,25 Hz,正弦波型,1次/d,30 min/次,持续4周施加振动刺激。 结果与结论:造模4周后,大体观察结果显示,振动组骨痂生长良好,组织学切片显示其新生骨量较多,可见大量成骨细胞,骨缺损与断端形成骨性连接;振动组Ⅰ型胶原蛋白、RUNX2 mRNA表达水平明显高于非振动组。提示振动应力刺激可促进骨缺损微环境中骨髓间充质干细胞的成骨分化能力,提高Ⅰ型胶原蛋白、RUNX2 mRNA表达水平,从而加速骨缺损修复的进程。  相似文献   

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背景:骨髓间充质干细胞诱导成骨而抑制成脂分化是骨质疏松症防治的关键,也是骨组织修复工程种子细胞的来源,Wnt信号通路对骨形成起着重要作用.目的:综述Wnt/β-catenin信号通路调控骨髓间充质干细胞成骨分化的相关因素及分子机制.方法:应用计算机检索CNKI、PubMed及万方医学数据库建库至2020年2月发表的相关...  相似文献   

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The chemical composition, structure and surface characteristics of biomaterials/scaffold can affect the adsorption of proteins, and this in turn influences the subsequent cellular response and tissue regeneration. With magnesium/calcium phosphate cements (MCPC) as model, the effects of magnesium (Mg) on the initial adhesion and osteogenic differentiation of bone marrow stromal cells (BMSCs) as well as the underlying mechanism were investigated. A series of MCPCs with different magnesium phosphate cement (MPC) content (0∼20%) in calcium phosphate cement (CPC) were synthesized. MCPCs with moderate proportion of MPC (5% and 10%, referred to as 5MCPC and 10MCPC) were found to effectively modulate the orientation of the adsorbed fibronectin (Fn) to exhibit enhanced receptor binding affinity, and to up-regulate integrin α5β1 expression of BMSCs, especially for 5MCPC. As a result, the attachment, morphology, focal adhesion formation, actin filaments assembly and osteogenic differentiation of BMSCs on 5MCPC were strongly enhanced. Further in vivo experiments confirmed that 5MCPC induced promoted osteogenesis in comparison to ot her CPC/MCPCs. Our results also suggested that the Mg on the underlying substrates but not the dissolved Mg ions was the main contributor to the above positive effects. Based on these results, it can be inferred that the specific interaction of Fn and integrin α5β1 had predominant effect on the MCPC-induced enhanced cellular response of BMSCs. These results provide a new strategy to regulate BMSCs adhesion and osteogenic differentiation by adjusting the Mg/Ca content and distribution in CPC, guiding the development of osteoinductive scaffolds for bone tissue regeneration.  相似文献   

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背景:Hedgehog信号通路是一个在胚胎阶段调控多种组织器官发育的重要信号通路,在成骨发育方面具有重要的作用。但Hedgehog信号分子在大鼠骨髓间充质干细胞体外诱导分化为成骨细胞过程中的作用尚未清楚。 目的:体外诱导大鼠骨髓间充质干细胞向成骨分化,检测Hedgehog信号分子在成骨诱导分化过程中的变化。 方法:从大鼠骨髓中分离得到骨髓间充质干细胞,进行地塞米松成骨诱导,通过免疫组化方法鉴定成骨的情况,Western Blot方法检测 Hedgehog信号分子SHH和IHH在骨髓间充质干细胞成骨分化过程中的表达。 结果与结论:成功分离得到骨髓间充质干细胞,地塞米松诱导培养7,14,21 d 后,Ⅰ型胶原的表达量逐渐增加;在诱导成骨分化过程中,SHH蛋白表达升高,诱导组的表达明显高于未诱导组的表达(P < 0.05),而IHH蛋白的表达降低,诱导组的表达明显低于未诱导组的表达(P < 0.05)。结果提示,Hedgehog信号分子参与地塞米松诱导骨髓间充质干细胞分化为成骨细胞的过程,且SHH和IHH在间充质干细胞诱导成骨过程中的作用有差异。  相似文献   

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Bone marrow- and adipose tissue-derived stromal cells (BMSCs and ASCs, respectively) exhibit a similar capacity for osteogenic differentiation in vitro, but it is unclear whether they share a common differentiation process, because they originate from different tissues. The aim of this study was to explore BMSC and ASC osteogenic differentiation by focusing on the expression of extracellular matrix-related genes (ECMGs), which play a crucial role in osteogenesis and bone tissue regeneration in vivo. We characterized the gene expression profiles of BMSCs and ASCs using a custom complementary deoxyribonucleic acid microarray containing 55 ECMGs. Undifferentiated BMSCs and ASCs actively expressed a wide range of ECMGs. Once BMSCs and ASCs were placed in an osteogenic differentiation medium, 24 and 17 ECMGs, respectively, underwent considerable downregulation over the course of the culture period. The remaining genes were maintained at a similar expression level to corresponding uninduced cell cultures. Although the suppression phenomenon was consistent irrespective of stromal cell origin, collagen (COL)2A1, COL6A1, COL9A1, parathyroid hormone receptor, integrin (INT)-beta3, and TenascinX genes were only downregulated in osteogenic BMSCs, whereas COL1A2, COL3A1, COL4A1, COL5A2, COL15A1, osteopontin, osteonectin, and INT-beta1 genes were only downregulated in osteogenic ASCs. During this time period, cell viability was sustained, suggesting that the observed downregulation did not occur by selection and elimination of unfit cells from the whole cell population. These data suggest that osteogenically differentiating BMSCs and ASCs transition away from a diverse gene expression pattern, reflecting their multipotency toward a configuration specifically meeting the requirements of the target lineage. This change may serve to normalize gene expression in mixed populations of stem cells derived from different tissues.  相似文献   

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Open wound contraction necessitates cell and connective tissue interactions, that produce tension. Investigating fibroblast responses to tension utilizes collagen coated polyacrylamide gels with differences in stiffness. Human foreskin fibroblasts were plated on native type I collagen-coated polyacrylamide gel cover slips with different rigidities, which were controlled by bis-acrylamide concentrations. Changes in alpha smooth muscle actin (αSMA), α2β1 integrin (CD49B) and αvβ3 integrin (CD-51) were documented by immuno-histology and Western blot analysis. Cells plated on rigid gels were longer, and expressed αvβ3 integrin and αSMA within cytoplasmic stress fibers. In contrast, cells on flexible gels were shorter, expressed α2β1 integrin and had fine cytoskeletal microfilaments without αSMA. Increased tension changed the actin makeup of the cytoskeleton and the integrin expressed on the cell's surface. These in vitro findings are in agreement with the tension buildup as an open wound closes by wound contraction. It supports the notion that cells under minimal tension in early granulation tissue express α2β1 integrin, required for organizing fine collagen fibrils into thick collagen fibers. Thicker fibers create a rigid matrix, generating more tension. With increased tension cytoskeletal stress fibers develop that contain αSMA and αvβ3 integrin that replaces α2β1 integrin, consistent with cell switching from collagen to non-collagen proteins interactions.  相似文献   

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In trabecular bone fracture repair in vivo, osteogenesis occurs through endochondral ossification under hypoxic conditions, or through woven bone deposition in the vicinity of blood vessels. In vitro osteogenesis assays are routinely used to test osteoblastic responses to drugs, hormones, and biomaterials for bone and cartilage repair applications. These cell culture models recapitulate events that occur in woven bone synthesis, and are carried out using primary osteoblasts, osteoblast precursors such as bone marrow-derived mesenchymal stromal cells (BMSCs), or various osteoblast cell lines. With time in culture, cell differentiation is typically assessed by examining levels of alkaline phosphatase activity (an early osteoblast marker) and by evaluating the assembly of a collagen (type I)-containing fibrillar extracellular matrix that mineralizes. In this review, we have made a comparative analysis of published osteogenic assays using calvarial cells, calvaria-derived cell lines, and bone marrow stromal cells. In all of these cell types, alkaline phosphatase activity shows similar progression over time using a variety of osteogenic and mineralizing media conditions; however, levels of alkaline phosphatase activity are not proportional to observed mineralization levels.  相似文献   

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背景:目前应用各种人造支架复合细胞修复骨缺损研究很多,但是各种人造支架都没有骨的天然结构,所以修复效果不够理想。 目的:将大鼠骨髓间充质干细胞接种到异种去蛋白松质骨上,移植修复大鼠股骨节段性缺损,以体内修复效果来评价复合体应用前景。 方法:分离培养大鼠骨髓间充质干细胞并进行扩增,用BrdU体外进行标记。同时制备牛去蛋白松质骨,在体外与标记后的细胞复合。制备大鼠双侧股骨中段5 mm缺损模型,实验分成3组,缺损处分别移植骨髓间充质干细胞/去蛋白松质骨复合体、单纯去蛋白松质骨及单纯骨髓间充质干细胞。 结果与结论:BrdU免疫染色结果显示,在各组细胞均呈阳性表达,但随着移植时间的延长而减弱。X射线放射学评分及苏木精-伊红染色组织学评分结果显示,各时间段复合体组成骨效果均好于其他组。复合体组Ⅰ型胶原蛋白表达随着时间的延长有明显增强,强于其他组。提示骨髓间充质干细胞复合异种去蛋白松质骨的成骨能力明显强于单纯的支架修复能力,单纯的骨髓间充质干细胞虽然有成骨能力,但不能修复节段性骨缺损。  相似文献   

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Human adipose-derived stromal cells (hASCs) have a proven capacity to aid in osseous repair of calvarial defects. However, the bone defect microenvironment necessary for osseous healing is not fully understood. In this study, we postulated that the cell-cell interaction between engrafted ASCs and host dura mater (DM) cells is critical for the healing of calvarial defects. hASCs were engrafted into critical sized calvarial mouse defects. The DM-hASC interaction was manipulated surgically by DM removal or by insertion of a semipermeable or nonpermeable membrane between DM and hASCs. Radiographic, histologic, and gene expression analyses were performed. Next, the hASC-DM interaction is assessed by conditioned media (CM) and coculture assays. Finally, bone morphogenetic protein (BMP) signaling from DM was investigated in vivo using novel BMP-2 and anti-BMP-2/4 slow releasing scaffolds. With intact DM, osseous healing occurs both from host DM and engrafted hASCs. Interference with the DM-hASC interaction dramatically reduced calvarial healing with abrogated BMP-2-Smad-1/5 signaling. Using CM and coculture assays, mouse DM cells stimulated hASC osteogenesis via BMP signaling. Through in vivo manipulation of the BMP-2 pathway, we found that BMP-2 plays an important role in DM stimulation of hASC osteogenesis in the context of calvarial bone healing. BMP-2 supplementation to a defect with disrupted DM allowed for bone formation in a nonhealing defect. DM is an osteogenic cell type that both participates in and stimulates osseous healing in a hASC-engrafted calvarial defect. Furthermore, DM-derived BMP-2 paracrine stimulation appears to play a key role for hASC mediated repair.  相似文献   

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The purpose of this study was to determine the influence of cocultured adipose-derived stromal cells (ASCs) in enhancing the osteogenic differentiation and angiogenesis of bone marrow stromal cells (BMSCs) as well as the underlying mechanism and the optimal ratio. Two in vitro coculture models, segregated cocultures using transwell and mixed cocultures, were employed to assess the indirect and direct effects of coculture respectively. Coculture was carried out for 14 days using 1 × 105 BMSCs and ASCs of variable number. BMSCs, ASCs, or both were seeded in PLGA scaffold and implanted in the subcutaneous tissue of 25 nude mice for in vivo analysis of angiogenesis. To evaluate the orthotopic bone formation, critical size calvarial defects were created on 20 mice, and implanted with hydroxyapatite/β-tricalcium phosphate granules plus BMSCs, ASCs, or both. From both transwell and mixed coculture model, 1 × 105 BMSCs cocultured with 0.5 × 105 ASCs showed significantly greater osteogenic differentiation and mineralization than BMSCs alone. The mixed ASC/BMSC coculture at or above a ratio of 0.5/1 showed increased secretion of vascular endothelial growth factor (VEGF), and induced effective tube formation from human umbilical vein endothelial cells, which were comparable to ASCs. Cytokine profiling assay and gene expression study showed elevated levels of angiogenic factors VEGF and CXCL1, osteogenic factor Wnt5a as well as transforming growth factor (TGF)-βR1 and SMAD3 from BMSCs when cocultured with ASCs. After 5 weeks of implantation, polylactic-co-glycolic acid (PLGA)-ASCs-BMSCs had a number of vascular structures comparable to PLGA-ASCs and significantly greater than PLGA-BMSCs. Calvarial defects treated with ceramic/BMSCs/ASCs had greater area of repair and better reconstitution of osseous structure than the defects treated with ceramic/ASCs or ceramic/BMSCs after 10 weeks. In conclusion, ASCs added to BMSCs promoted osteogenesis and angiogenesis at the optimal ASC/BMSC ratio of 0.5/1.  相似文献   

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The bone mesenchymal stem cells (BMSCs) were seeded on [poly(lactide-co-glycolide) scaffolds with hydroxyapatite (HA) coating, and "s" stands for surface] (PLGA/HA-S), PLGA/HA-M (containing the same HA amount in the matrix as that of the PLGA/HA-S and "m" stands for matrix), and PLGA scaffolds, which were then cultured in a medium-containing Escherichia coli-derived recombinant human bone morphogenetic protein-2 (ErhBMP-2). In vitro culture of rat BMSCs found no different cell morphology in all the scaffolds, but the alkaline phosphatase activity and osteogenic gene expression of type I collagen (COL I) and osteocalcin (OCN) in the PLGA/HA-S scaffolds were always highest and were significantly improved in comparison with those in the PLGA scaffolds. In a rat calvarial defect model, new bone formation was enhanced in the PLGA/HA-S/ErhBMP-2 implants at 4 and 8 weeks after implantation too. Therefore, the PLGA/HA-S scaffold can better enhance the ErhBMP-2-induced osteogenic differentiation of BMSCs in vitro and osteogenesis in vivo.  相似文献   

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BACKGROUND: Bushen Huoxue Decoction (BSHXD) can promote osteogenesis of bone marrow mesenchymal stem cells (BMSCs) in vitro. Exploring the molecular mechanisms involved is of clinical benefits. OBJECTIVE: To discuss the changes in the expression of SP7/Osterix and alkaline phosphatase (ALP) in BMSCs with Cbfal/RUNX2 gene silencing regulated by the water extracts from BSHXD. METHODS: BMSCs were isolated and cultured by the bone marrow adherent method, and BMSCs at passage 3 were used in the assay. BMSCs were transfected with nothing (blank control group), Cbfal/RUNX2 gene silencing lentivirus (silencing group), and negative viral vector (negative control group), respectively. Then, the cells were cultured in 100 mg/L BSHXD water extract, and 3 days later, the protein and mRNA expression of RUNX2 and Osterix was detected by western blot and qPCR, respectively. Activity of ALP in the BMSCs was also detected in each group. RESULTS AND CONCLUSION: The transfection efficiency of Cbfal/RUNX2 gene silencing lentivirus was about 90%. The protein and mRNA expressions of RUNX2 and Osterix were significantly decreased in the BMSCs transfected with Cbfal/RUNX2 gene silencing lentivirus as compared with the other two groups, and so was the ALP activity (P < 0.01). After treated with the water extracts from BSHXD, the expression of RUNX2 and Osterix as well as the ALP activity in the BMSCs transfected with Cbfal/RUNX2 gene silencing lentivirus increased significantly (P < 0.01). To conclude, the water extract from the BXHXD can up-regulate the expression of RUNX2 and Osterix and the activity of ALP, thus promoting BMSCs osteogenic differentiation. © 2018, Journal of Clinical Rehabilitative Tissue Engineering Research. All rights reserved.  相似文献   

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To better understand the effects of scaffold materials for bone morphogenetic protein 2 (BMP-2) genetic tissue engineering in vivo, several gels, including alginate, collagen, agarose, hyaluronate, fibrin, or Pluronic, were mixed with adenovirus-mediated human BMP-2 gene (Adv-hBMP-2) transduced bone marrow stromal cells (BMSCs) and injected into the muscles of athymic mice to evaluate the resulting osteogenesis and chondrogenesis. These gel and gene-transduced BMSC mixtures were also loaded onto beta-TCP/HAP biphasic calcined bone (BCB) and observed under scanning electron microscopy (SEM). In addition, these composite scaffolds were implanted into the subcutaneous site of athymic mice to construct tissue-engineered bone. After injection, collagen, hyaluronate, or alginate gel mixed with gene-transduced BMSCs induced more bone formation than a cell suspension in alpha-MEM. The agarose-gene-transduced BMSC gel was found to contain much more hyaline cartilage. SEM showed the BMSCs could survive in alginate, agarose, and collagen gel in vitro for up to 8 d. After implantation of tissue-engineered bone, the alginate, collagen, and agarose gel could promote new bone formation within a BCB in vivo. Little or no bone formed after injection of fibrin or Pluronic gel mixed with BMSCs or implantation with BCB. These findings help to elucidate the effects of various scaffold materials for future research in orthopedic tissue engineering using BMP-2 transduced cells.  相似文献   

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目的:探究随机肌腱细胞外基质(ECM)支架对骨髓间充质干细胞(BMSCs)活力和分化的影响。方法:从Sprague-Dawley大鼠股骨和胫骨中提取BMSCs,体外培养,观察细胞形态,并利用流式细胞术鉴定细胞干性。采用1%Triton X-100和DNase/RNase混合液对鼠尾肌腱进行脱细胞处理,利用HE染色和DNA含量测定考察肌腱组织中细胞核残余情况。制备胶原纤维随机排列的肌腱ECM支架,培养BMSCs,以孔板中生长的细胞为对照组,利用Live/Dead染色和CCK8法考察细胞的活力和形态;利用RT-qPCR检测肌腱标志物I型胶原蛋白(Col I)、肌腱特异转录因子scleraxis(SCX)及成骨标志物碱性磷酸酶(ALP)和Runt相关转录因子2(RUNX2)的表达水平。结果:HE染色结果显示,经过脱细胞处理后肌腱组织内无细胞残余,且DNA含量从(481.7±15.8)μg/g显著性降至(31.0±3.8)μg/g(P<0.05),脱细胞处理成功。7 d时,种植在支架上的BMSCs的活力较对照组显著增强(P<0.05);14 d时,种植在支架上的BMSCs肌腱标志物Col I和SCX的表达量较对照组显著下调,而成骨标志物ALP和RUNX2的表达量较对照组显著上调(P<0.05)。结论:脱细胞随机肌腱ECM支架能增强BMSCs活力,并诱导其向成骨细胞分化。  相似文献   

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背景:骨髓间充质干细胞发挥成骨作用需要支架材料的辅助,一方面支架材料不仅可将细胞运载至骨缺损区域,另一方面还可作为新骨生长的框架结构。胶原-壳聚糖复合材料是骨组织工程较为理想的支架材料之一,同时其具有骨诱导性,比常规支架材料更优越的成骨能力。骨搬移技术在临床上在修复长段骨缺损方面已得到广泛应用,但也存在成骨慢、外固定时间长、骨不连等缺憾。如何进一步加快骨形成速度,减少并发症发生,已成当前亟待解决的问题。实验假设:骨髓间充质干细胞复合胶原-壳聚糖支架移植能提高胫骨缺损骨搬移修复效果。 方法/设计:随机对照动物实验。分为体外和体内实验两部分。体外实验中取月龄一两个月的新西兰大白兔股骨骨髓,提取骨髓间充质干细胞,培养至第3代,将细胞悬液滴于胶原-壳聚糖支架材料,构建骨髓间充质干细胞复合胶原-壳聚糖支架。体内实验选用24只三四月龄新西兰大白兔,被随机分配接受如下干预:骨搬移、支架植入、骨搬移联合支架植入。研究的主要观察指标为植入材料与骨缺损界面的生长情况、X射线检测的缺损区骨修复情况、苏木精-伊红染色及扫描电镜观察缺损区成骨情况、免疫组织化学染色检测成骨区Ⅰ型胶原蛋白的表达情况、扫描电子显微镜观察移植材料与宿主骨的界面键合情况、超微结构及新骨的生成。 讨论:实验结果将有助于确定对骨缺损进行骨搬移治疗过程中,应用骨髓间充质干细胞复合胶原-壳聚糖支架移植促进骨缺损再生修复效果的可行性。 实验方案获基金支持情况:获辽宁省科学技术计划项目资助(2012225019)。 中国组织工程研究杂志出版内容重点:干细胞;骨髓干细胞;造血干细胞;脂肪干细胞;肿瘤干细胞;胚胎干细胞;脐带脐血干细胞;干细胞诱导;干细胞分化;组织工程  相似文献   

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阮蔷  赵刚  郭睿  肖月  李超 《中国组织工程研究》2016,20(38):5657-5663
BACKGROUND: Bone tissue transplantation or osteogenic material filling is after used for bone defect repair. To remove autologous bone tissues can lead to additional damage and secondary deformity, therefore, it is extremely urgent to search for a new osteogenic material. OBJECTIVE: To construct the porous β-tricalcium phosphate (β-TCP)/collagen scaffold modified with human bone morphogenetic protein 2 (hBMP2) gene, and to observe its effects on differentiation of MC3T3-E1 cell lines. METHODS: The porous β-TCP/collagen scaffold modified with hBMP2 gene was prepared. Then in vitro culture system of MC3T3-E1 cell lines with composite scaffold was established. There were scaffold and plate groups, and each group was divided into two subgroups according to the different concentrations of plasmid. Samples were collected and observed morphologically by scanning electron microscope and light microscope after complex culture. After 1, 3, 7 and 14 days of induction, calcium nodules were observed through alizarin red staining, the cell cycle was detected by real-time PCR, and expressions of α I-chain collagen type I gene, Osterix and bone sialoprotein were observed. RESULTS AND CONCLUSION: The number of cells adhered, differentated and distributed on the composite scaffold was significantly higher than that of the single scaffold (P < 0.05). Alizarin red staining and real-time PCR detection showed that the osteogenesis ability of MC3T3-E1 cell lines in the scaffold group was stronger than that in the plate group. To conclude, the porous β-TCP/collagen scaffold modified with hBMP2 gene is an appropriate candidate for bone defect repair.  相似文献   

20.
背景:采用低频脉冲电磁场干预骨髓间充质干细胞增殖分化的研究很多,但采用高频(> 300 MHz)脉冲电磁场干预的研究国内未见报道。 目的:观察> 300 MHz高频脉冲电磁场照射能否促进骨髓间充质干细胞增殖,并向成骨分化。 方法:分离培养SD大鼠骨髓间充质干细胞,取第3代细胞随机分为4组:成骨诱导组、成骨诱导+电磁照射组、电磁场照射组、空白对照组。观察各组骨髓间充质干细胞培养过程中细胞形态、数量、总蛋白量等方面变化。 结果与结论:与未经高频脉冲电磁场照射组相比,经高频脉冲电磁场照射后,骨髓间充质干细胞胞体稍有增多,但分化方面区别微弱。电磁场照射组细胞增殖速度、总蛋白含量均低于较空白对照组(P  < 0.05)。但电磁照射组细胞凋亡率较空白对照组增加(P < 0.05)。说明高频脉冲电磁场促进骨髓间充质干细胞的成骨分化趋势不明显,可抑制其增殖,促进其凋亡。  相似文献   

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