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121.
骨髓间质干细胞体外预构组织工程化肌腱的实验研究 总被引:2,自引:1,他引:1
目的探讨骨髓间质干细胞与胶原-聚羟基乙酸的细胞相容性,为构建组织工程化肌腱寻求理想方法.方法以贴壁法分离、培养骨髓间质干细胞,并检测CD44.在实验组中将骨髓间质干细胞置入含胶原-聚羟基乙酸的DMEM培基中培养:在对照组中将骨髓间质干细胞置入DMEM培基中培养.通过MTT方法比较两组的细胞活性和生长情况,并对实验组进行超微观察.以骨髓间质干细胞为种子细胞,以胶原-聚羟基乙酸为支架在体外预构组织工程化肌腱.结果以贴壁法原代培养骨髓间质干细胞,11天细胞即汇合成片,检测CD44示阳性.骨髓间质干细胞接种于胶原-聚羟基乙酸中混合培养后14天生长良好,始终保持89%以上的细胞活力,与对照组比较无显著差别;实验组细胞数未发生明显改变,而对照组从第4天开始即发生增殖.透射电镜示实验组细胞培养14天后仍保持旺盛的分泌功能.体外预构的组织工程化肌腱具有良好的形态,细胞伸展成梭形,沿聚羟基乙酸缝线大致平行排列.结论骨髓间质干细胞与胶原-聚羟基乙酸的细胞相容性好.以骨髓间质干细胞为种子细胞,以胶原-聚羟基乙酸为支架可在体外初步预构组织工程化肌腱. 相似文献
122.
Experimental Study on Allogenic Decalcified Bone Matrix as Carrier for Bone Tissue Engineering 总被引:11,自引:0,他引:11
The biocompatibility and osteogenic activity of allogenic decalcified bone matrix (DBM) used as a carrier for bone tissue engineering were studied. Following the method described by Urist, allogenic DBM was made. In vitro, DBM and bone marrow stromal cell (BMSC) from rab-bits were co-cultured for 3-7 days and subjected to HE staining, and a series of histomorphological observations were performed under phase-contrast microscopy and scanning electron microscopy (SEM). In vivo the mixture of DBM/BMSC co-cultured for 3 days was planted into one side of muscules sacrospinalis of rabbits, and the DBM without BMSC was planted into other side as con-trol. Specimens were collected at postoperative week 1, 2 and 4, and subjected to HE staining, and observed under SEM. The results showed during culture in vitro, the BMSCs adherent to the wall of DBM grew, proliferated and had secretive activity. The in vivo experiment revealed that BMSCs and undifferentiated mesenchymal cells in the perivascular region invaded gradually and proliferated together in DBM/BMSC group, and colony-forming units of chondrocytes were found. Osteoblasts,trabecular bone and medullary cavity appeared. The inflammatory reaction around muscles almost disappeared at the second weeks. In pure DBM group, the similar changes appeared from the sur-face of the DBM to center, and the volume of total regenerate bones was less than the DBM/BMSC group at the same time. The results indicated that the mixture of DBM and BMSC had good bio-compatibility and ectopic induced osteogentic activty. 相似文献
123.
Tarja A. Soininvaara Hannu J.A. Miettinen Jukka S. Jurvelin Esko M. Alhava Heikki P.J. Kröger 《Journal of clinical densitometry》2004,7(4):424-431
Osteoarthrosis (OA) is often associated with pain and disability, which are relieved after total knee arthroplasty (TKA), but the nature of bone changes associated with OA is controversial. We examined preoperative hip and contralateral knee bone mineral density (BMD) in patients requiring TKA and monitored the BMD changes postoperatively. Sixty-nine patients, scheduled to have TKA for osteoarthrotic knees, had both hips and contralateral knee BMD measured by dual-energy X-ray absorptiometry (DXA) at the time of operation (baseline) and at 1 yr after operation. X-rays of the knee joints were also taken to evaluate the severity of OA. Preoperatively, 27% and 38% of the patients had total hip BMD Z-score more than 1 SD in the operated side and contralateral hips, respectively. In all regions of interest (ROI), the mean baseline BMD of the affected side proximal femur was significantly lower than that of the contralateral side (p < 0.0005-0.019). The severity of OA was not associated with BMD. During 1-yr follow-up, the postoperative knee status and the physical activity of the patients (AKS score) improved. However, neither the hip nor the nonoperated knee BMDs increased. Knee OA is associated with significantly lower BMD values in the affected side compared with the contralateral hip, and these levels remained similar or decreased during a 1-yr follow-up. We conclude that improved mobility after TKA does not improve the effects of preoperative disuse-associated bone loss in the short term. 相似文献
124.
逆行交锁髓内钉治疗股骨远段骨折 总被引:11,自引:0,他引:11
目的 总结股骨逆行交锁髓内钉应用的适应证、优点及其疗效。方法 2001年6月~2003年6月,采用切开复位股骨逆行交锁髓内钉内固定,治疗股骨远段骨折21例,早期行膝关节功能锻炼。结果 18例获随访,全部骨性愈合,功能恢复良好,无膝痛、跛行、膝关节僵直等。结论 股骨逆行交锁髓内钉治疗股骨远段骨折具有明显优势,固定牢固、坚强,功能恢复快,并发症少等优点,手术不需要C臂X线机和骨科手术牵引床,适合基层医院临床应用。 相似文献
125.
大鼠骨髓间充质干细胞转染人TH基因的实验研究 总被引:1,自引:1,他引:0
目的评价酪氨酸羟化酶(tyrosine hydroxylase,TH)基因修饰骨髓间充质干细胞(mesenchymalstem cells,MSCs)后TH的表达情况及转染TH基因对MSCs的影响.方法构建含人TH基因的pCMV/hTH质粒,用脂质体转染原代培养的大鼠MSCs;Western blot及免疫细胞化学染色鉴定TH基因的表达及MSCs的分化情况;MTT比色法测定转染后的MSCs细胞活性,并与未转染的MSCs进行细胞活性比较.结果构建的pCMV/hTH质粒经ECoRI酶切后产生1.9okb和5.3kb的片段,与回收的目的基因及载体基因片段大小相符;转基因后的MSCs Western blot及免疫细胞化学染色显示TH染色阳性;转染后MSCs未见有NeuN,GFAP的表达;MTT比色法测定细胞活性,未转染与转染者差异无显著性.结论构建的TH基因能在体外培养的鼠MSCs中较好的表达,转染不会诱导MSCs向神经样细胞分化,对MSCs细胞活性无明显影响. 相似文献
126.
127.
目的目前国内对QCT骨密度测量的质量控制研究较少,本文介绍了QCT骨密度测量的准确度、精密度试验方法和意义。方法使用东芝CT机自带体模和软件为测量工具,测量四川大学华西骨质疏松研究中心等研制的QCT骨体模(称四川体模)的骨密度值。四川体模固定于15cm深的水浴中模拟人体腰椎,东芝体模置于水浴容器与扫描床面之间,按照人腰椎QCT骨密度测量相同的条件和方法进行操作,每日1次对测量体模连续测量25日,计算SD和CV,分别以25次测量125d25次测量/1d基线作3m的shewhart图。结果测量四川体模从小到大三管骨密度分别的准确度误差为-60.4%、-39.1%和-13.6%,其分别的校正系数为2.69、1.64、1.15,相关系数为0.9966,回归方程Y=35.6+0.958X(X为测量骨密度,Y为校正后骨密度)。本型QCT机骨密度测量的25次/1d及25次,25d精密度误差分别为1.25~5.54%和1.98~7.87%。25次125d的精密度误差要大于25次,d,显示机器一日内精密度误差变化小,随时间延长其变化增大。以25次125d的结果为基线绘制的shewhart图优于25次/d。结论一切QCT骨密度测量都应进行质量控制,准确度必须予以校正,精密度试验应在此基础上进行。这样结果才真实、科学、可靠并具有可比性。 相似文献
128.
Disaggregation of bone into crystals 总被引:6,自引:0,他引:6
Summary The sizes, shapes, and organizational states of the crystals in bone are studied by systematic disaggregation of the mineral
phase. This is achieved by oxidizing the organic phase with sodium hypochlorite, dispersing the resultant particles by sonication,
and separating the crystal aggregates from the crystal monomers by gravity setting in ethanol. Six different bones are compared.
Bones in which crystals are intimately associated with the collagen fibrils mostly disaggregate into crystal monomers. In
dense bones, where the crystals are mostly located between fibrils, they tend to persist as “fused” aggregates. All the crystals
are tabular or plate-shaped. In bones in which the majority of crystals are associated with the collagen fibrils, just less
than 90% of the crystals are shorter than about 450 ? in length. Their widths are on the average about 250 ?, almost an order
of magnitude larger than the diameters of individual gap regions within the collagen fibril. The notion that one crystal is
located in one gap region is therefore untenable and a reevaluation of the relations between collagen and mineral in bone
is necessary. 相似文献
129.
Effect of Ligustrazine on Bone Marrow Microenvironment and Signal Transducti on Path in Irradiation Injured Mice
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Lan Sun Wen-li Liu Han-ying Sun Tian-hua Ren Deng-ju Li Hui-zhen Xu Wu Lu 《中国结合医学杂志》2002,8(4):295-298
Wehavereported previouslythatligustrazinecouldpromotehematopoiesisthroughimprovingbonemarrowmicroenvironmentandenhancingadhesive 相似文献
130.
颈椎骨折常合并有不同程度的脊髓神经功能损伤及颈椎不稳定,对颈脊髓损伤治疗的目的是恢复颈椎的生理解剖关系,重建脊柱的稳定性,防止神经组织的继发性损伤,促进神经功能的恢复,早期无痛情况下的功能康复。2000年8月至2004年8月应用前路槽式减压自体长方体髂骨植骨钛合金钢板固定治疗下颈椎骨折46例,效果满意,总结如下。1临床资料本组46例,均为男性,年龄21~62岁,平均47·3岁。受伤原因:交通事故伤26例,坠落伤20例。骨折部位:C33例,C412例,C516例,C610例,C4、C5同时骨折5例。骨折类型:垂直压缩性骨折4例,屈曲型压缩性骨折23例,过伸型压缩… 相似文献