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1.
目的依据仿生原理制备新型的胶原多糖基纳米羟基磷灰石(HA)复合骨支架材料,并与成骨细胞复合培养,检测其细胞相容性。方法以胶原分子与透明质酸钠的交联产物为模板,调制钙磷盐在液相中沉积其上,得到矿化胶原多糖基复合材料;采用液相分离法与少量聚乳酸复合进一步制备成为三维多孔支架,使用成骨细胞(Mc3T3-E1)接种于该支架上培养。用X—ray衍射、扫描电镜、万能材料测试机等对材料进行观察和测试分析;并用倒置相差显微镜、荧光显微镜、扫描电镜、CCK-8细胞计数试剂盒、碱性磷酸酶(ALP)活性测定等观察和分析细胞在支架材料中的生长、分化情况。结果胶原多糖基纳米HA仿生复合材料的晶粒度较低,晶体极为细小,与天然骨中羟基磷灰石的组装结构类似;该复合支架为多孔状,孔隙率约82%,孔径大小为200~650μm;抗压性能好,成骨细胞可在其上贴附、生长和繁殖,并表现出较高的成骨活性。结论所制备的胶原多糖基纳米HA仿生骨支架材料,无论从组分和结构上均与天然松质骨类似,与成骨细胞相容性好,可望成为较理想的骨组织工程支架材料。  相似文献   

2.
背景:烧结的钙磷多孔陶瓷由于其表面结构致密,在诱导细胞黏附和生长方面仍存在不足。目的:观察表面明胶处理对钙磷多孔陶瓷细胞相容性的影响。方法:以羟基磷灰石和磷酸钙为主要原料,采用有机泡沫浸渍工艺制备钙磷多孔陶瓷,然后将多孔陶瓷浸于5%的明胶溶液中进行表面处理。扫描电镜观察处理前后样品的孔隙形貌和表面结构,阿基米德法测试样品的孔隙率,WD-10A型电子万能材料试验机测定压缩强度;将材料与兔骨髓基质干细胞进行体外复合培养,通过MTT实验和扫描电镜观察细胞在材料上的生长情况。结果与结论:表面明胶处理后,多孔陶瓷的孔壁表面形成了较均匀的明胶涂层,样品的孔隙特征并没有受到显著影响。然而它们的平均压缩强度却从(1.04±0.15)MPa提高到了(5.17±0.17)MPa。扫描电镜观察和MTT实验结果表明,表面涂覆处理前后的多孔材料都具有良好的细胞相容性。与烧结的多孔陶瓷相比,表面明胶处理的样品更能增进细胞在材料表面的早期黏附和增殖。结果表明表面明胶处理在不破坏多孔陶瓷孔隙特征的情况下,不仅提高了钙磷多孔陶瓷的力学性能,而且改善了多孔陶瓷的细胞相容性。  相似文献   

3.
多孔碳酸化羟基磷灰石骨水泥的生物相容性研究   总被引:2,自引:0,他引:2  
目的探讨一种新型的代骨材料--多孔碳酸化羟基磷灰石骨水泥的组织相容性.方法合成碳酸化羟基磷灰石骨水泥,添加成孔剂,制备能原位固化形成多孔结构的碳酸化羟基磷灰石代骨材料,并通过细胞毒性实验和肌内埋植实验检测其组织相容性.结果多孔碳酸化羟基磷灰石骨水泥的浸提液对骨髓基质细胞的生长无影响.细胞于材料表面的生长速度、形态与空白对照组无差别.肌内植入实验发现,材料周围纤维组织包膜的最大厚度为22.5μm,未发现炎性细胞反应.结论多孔碳酸化羟基磷灰石骨水泥具有良好的组织相容性,材料测试结果符合标准.  相似文献   

4.
探讨新型聚己内酯(PCL)/磷酸钙(CPC)复合材料支架的制备方法及对骨髓基质细胞(BMSCs)的生物相容性。采用溶液共混法,利用可溶盐晶体做造孔剂,制备PCL/CPC复合材料支架,以单纯PCL和CPC支架为对照组,Q800型动态力学分析仪进行动态力学性能试验(DMA),采用排水法测量孔隙率;灭菌后通过与犬BMSCs体外共同培养后细胞形态、生长曲线、碱性磷酸酶(ALP)染色和半定量及骨钙素(OC)半定量等方法检测细胞在支架材料上的黏附、增殖及成骨分化情况,动物体内异位成骨检测其成骨情况。结果显示,复合材料的储能模量在PCL/CPC比例为7:3时达到最大,制得的材料孔径为250~350μm,多孔支架的孔隙率为70%~80%;BMSCs在新型PCL/CPC组、CPC组支架表面分布均匀,生长增殖明显较PCL组活跃(P<0.05);PCL/CPC组、CPC组BMSCs成骨行为与PCL组之间有显著差异(P<0.05)。动物体内异位成骨检测提示,4周时PCL/CPC组为13.78%±1.60%、CPC组BMSCs为15.29%±1.20%,成骨显著强于PCL组BMSCs的7.56%±2.20%(P<0.05),表明PCL和CPC的复合明显改善了两种材料的缺陷,获得的PCL/CPC支架具有良好的生物相容性,可与BMSCs共同构建具有成骨能力的三维立体组织工程化骨。  相似文献   

5.
背景:低温快速成型技术具有支架成型可控性、保持材料生物学活性和易于实现支架材料的三维多孔立体结构等优势,被迅速用于骨组织工程支架的制备。目的:采用低温快速成型制备聚乙二醇改性聚乳酸-乙醇酸/纳米羟基磷灰石复合支架,并检测其性能。方法:采用低温快速成型设备分别制备聚乙二醇改性聚乳酸-乙醇酸/纳米羟基磷灰石与聚乳酸-乙醇酸/纳米羟基磷灰石复合支架,通过电镜观察支架超微结构,以介质(乙醇)浸泡法测定支架孔隙率,采用电子试验机检测支架力学性能;将两种支架材料分别与大鼠成骨细胞共培养,培养12 h采用沉淀法检测细胞黏附率,培养1,3,5,7,9,12 d采用CCK-8法检测细胞增殖。结果与结论:两组支架孔径均在理想范围内并具有较高孔隙率,但聚乙二醇改性聚乳酸-乙醇酸/纳米羟基磷灰石支架的孔径波动范围大,孔径均值较聚乳酸-乙醇酸/纳米羟基磷灰石支架小且部分有闭塞现象。聚乙二醇改性聚乳酸-乙醇酸/纳米羟基磷灰石支架的细胞黏附率及表面细胞增殖活性高于聚乳酸-乙醇酸/纳米羟基磷灰石支架(P0.05),力学性能低于聚乳酸-乙醇酸/纳米羟基磷灰石支架(P0.05)。表明聚乙二醇改性聚乳酸-乙醇酸/纳米羟基磷灰石复合支架具有良好的细胞相容性。  相似文献   

6.
背景:人们对壳聚糖/羟基磷灰石复合多孔生物支架在体内的降解过程并非十分清楚,而且有关其降解产物对成骨细胞的影响研究也较少。目的:分析大鼠成骨细胞与壳聚糖/羟基磷灰石复合多孔生物支架降解产物的生物相容性。方法:将培养的第2代大鼠成骨细胞分别在壳聚糖/羟基磷灰石复合支架降解产物浸提液和含体积分数10%胎牛血清的DMEM培养液中培养,培养第2,4,6,8,10天分别对两组细胞做MTT细胞计数,采用联合会推荐法测定细胞碱性磷酸酶活性,采用BCA蛋白定量法测定总蛋白。结果与结论:在壳聚糖/羟基磷灰石复合多孔生物支架降解产物浸提液中培养的大鼠成骨细胞增殖速度、细胞碱性磷酸酶活性、细胞总蛋白合成及碱性磷酸酶与总蛋白的比值明显高于在体积分数为10%胎牛血清DMEM培养液中培养的细胞(P0.05)。表明壳聚糖/羟基磷灰石复合多孔生物支架的降解产物不仅可促进大鼠成骨细胞的黏附、生长和增殖,还可增强其骨化功能,具有较好的生物相容性。  相似文献   

7.
背景:采用发泡剂成孔技术,制成了有知识产权的新型骨修复材料多孔碳酸化羟基磷灰石,既保留了碳酸化羟基磷灰石骨水泥原位固化性能等所有的优点,同时又形成多孔结构。目的:通过动物实验观察新型的骨修复材料多孔碳酸化羟基磷灰石水泥修复骨缺损的力学效果。方法:30只新西兰大白兔,手术组25只在双侧股骨髁制备直径为5.5mm、深12mm的骨缺损动物模型,左侧植入多孔碳酸化羟基磷灰石骨水泥为实验组,右侧植入碳酸化羟基磷灰石骨水泥为对照组。非手术组5只,用于正常力学对照。将多孔碳酸化羟基磷灰石骨水泥和碳酸化羟基磷灰石骨水泥试件经模仿体液浸泡,检测力学强度。同时在手术组背肌内分别植入多孔碳酸化羟基磷灰石骨水泥和碳酸化羟基磷灰石骨水泥标准试件。分别于术后2,4,8,12,16周分批处死动物,进行试件骨内和肌内植入的力学实验分析和试件在模仿体液中浸泡后的抗压强度测试。结果与结论:多孔碳酸化羟基磷灰石骨水泥:2周时的骨内力学强度较低,4周时降到最低,8周时接近正常松质骨强度,12周时超过正常松质骨强度,16周时恢复到正常松质骨水平。碳酸化羟基磷灰石骨水泥:2周时骨内植入强度较多孔碳酸化羟基磷灰石骨水泥略高,4周时有所降低,8,12,16周时略升高,但是始终低于正常松质骨的强度。多孔碳酸化羟基磷灰石骨水泥和碳酸化羟基磷灰石骨水泥在SBF中浸泡的抗压强度变化不大。试件植入肌内后抗压强度变化非常显著。结果表明,多孔碳酸化羟基磷灰石水泥具有原位固化性能和一定的力学支撑作用,能作为自体骨移植的一种替代物修复骨缺损。  相似文献   

8.
背景:大量的研究表明,应用于骨组织工程的材料,如羟基磷灰石及高分子聚乳酸等,均对骨缺损的修复起到了一定的作用。但单一的材料在组织相容性及仿生学等特点诸多方面,无法满足骨组织生长的需要,将现有的单一材料进行改性再复合产生新的材料是骨组织工程发展的一个重要方向。目的:通过静电纺丝技术制备共混的聚乳酸-聚乙二醇共聚物/表面接枝羟基磷灰石复合纤维材料,探讨表面接枝羟基磷灰石的引入及其在材料中的含量对成骨细胞在新型材料黏附、增殖和细胞活性的影响。方法:通过调整静电纺丝溶液中聚乳酸-聚乙二醇共聚物和表面接枝羟基磷灰石的4个质量百分数比例,5%/0%,5%/5%,5%/10%,5%/15%,分别制备的4种新型材料(样品1,2,3,4)与小鼠成骨细胞共培养,在特定的时间点,通过细胞染色、碱性磷酸酶检测等实验方法,获得4种不同材料对与之共培养的成骨细胞的相关数据。通过对上述数据进行统计分析,评价新型材料对成骨细胞黏附、增殖能力及细胞活性的影响。结果与结论:在细胞黏附实验中,3组含有表面接枝羟基磷灰石成分的新型材料与不含的材料相比,细胞数量均增长明显,各组细胞增殖情况和碱性磷酸酶活性从高到低依次为样品3组样品4组样品2组样品1组(P0.05)。结果证实,聚乳酸-聚乙二醇共聚物中引入表面接枝羟基磷灰石后其生物活性得到提高,且新型材料中表面接枝羟基磷灰石含量可影响材料与成骨细胞相容性及细胞活性。  相似文献   

9.
目的 制备多孔铌并评价其相关性能.方法 采用新型的泡沫浸渍法,以聚氨酯泡沫为载体制备出具有较高强度和良好生物相容性的多孔铌基材料.并借助分析天平、XRD、CS600碳硫测试仪和SEM对多孔铌的孔隙率、性能和微观结构进行了测试及观察,运用细胞生物学技术评价多孔铌的细胞生物相容性.结果 多孔铌具有三维、连通孔隙结构且无任何杂质相,孔隙率为71.4%,孔径500 μm,平均密度为2.45 g/cm3,具有与人体松质骨相匹配的弹性模量和抗压强度;多孔铌不影响成骨细胞的增殖、黏附和表型表达.结论 多孔铌具有高孔隙率结构,良好的力学性能及细胞生物相容性.  相似文献   

10.
目的观察成人成骨细胞在多孔钛表面的生长情况,评价多孔钛的生物相容性。方法将成人骨髓来源的成骨细胞与多孔钛联合培养,以多孔羟基磷灰石(hydroxyapatite,HA)为对照,倒置显微镜、扫描电镜观察细胞生长情况,MTT法检测细胞活性。结果成骨细胞在钛微孔表面生长良好,MTT法检测细胞活性,两组吸光度值无显著性差异(P〉0.05)。结论多孔钛具有良好的生物相容性,是比较理想的成骨细胞载体。  相似文献   

11.
Sodium hexametaphosphate (Na-HMP) is a common liquefying agent widely used in the ceramics industry for modifying the rheological behavior of ceramic slurries. The objective of this study was to investigate the influence of Na-HMP on several properties of calcium phosphate cements (CPCs). Various types of CPCs were prepared by mixing the same powder, namely, a mixture of tetracalcium phosphate and dicalcium phosphate anhydrate, with various liquids, namely, distilled water, Na(2)HPO(4) solutions, and Na-HMP solutions. The setting time, mechanical strength, rheological properties, and injectability of the cement pastes were examined in this work. Also, X-ray diffractometry (XRD) and scanning electron microscopy (SEM) techniques were employed for phase analysis and morphological evaluations, respectively. The results showed that, compared to CPCs made with water and Na(2)HPO(4) solutions, the CPC pastes made with Na-HMP solutions had improved stability and injectability but prolonged setting times. The XRD and SEM studies showed that Na-HMP inhibited the growth of apatite crystals during soaking of the cements in Ringer's solution. Thus, the CPC made with Na-HMP solution had lower compressive strength than those made with water or Na(2)HPO(4) solutions. Although Na-HMP could improve the injectability and stability of the CPC paste, it impaired other basic properties of the cement. Thus, it is not an appropriate liquefier additive.  相似文献   

12.
In the present study, macroporous calcium phosphate cements (CPCs) were prepared using a porogen; that is, the gas-foaming technique. The objective was to investigate the influence of the acidic component of the porogen (acetic acid versus citric acid) on several properties of a specified CPC. In all of the cements prepared, the basic component of the porogen was the same, namely, NaHCO(3), and it was added to the powder phase of the cement, while the acidic component of the porogen was dissolved in the liquid phase of the cement. The cements were characterized in terms of initial setting time, porosity, crystallinity, injectability and compressive strength. Also, XRD, FTIR, and SEM techniques were employed to evaluate the phase composition, the chemical groups and the morphological aspects of the porous cements during setting. It was found that the presence of a porogen in a CPC led to significant decreases in both its initial setting time and compressive strength. A CPC made using acetic acid contained a larger amount of the apatite phase but was significantly less injectable and less porous than when citric acid was used.  相似文献   

13.
The bone regenerative properties of calcium phosphate cements (CPCs) may be improved by the addition of growth factors, such as recombinant human transforming growth factor-beta1 (rhTGF-beta1). Previously, we showed that rhTGF-beta1 in CPC stimulated the differentiation of preosteoblastic cells from adult rat long bones. The intermixing of rhTGF-beta1 in CPC, which was subsequently applied to rat calvarial defects, enhanced bone growth around the cement and increased the degradation of the cement. However, it is unknown whether the addition of rhTGF-beta1 changes the material properties of CPC and what the characteristics of the release of rhTGF-beta1 from CPC are. Therefore, we determined in this study the release of rhTGF-beta1, in vitro, from the cement pellets as implanted in the rat calvariae. The possible intervening effects of rhTGF-beta1 intermixing on the clinical compliance of CPC were studied through an assessment of its compressive strength and setting time, as well as its crystallinity, calcium-to-phosphorus ratio, porosity, and microscopic structure. We prepared CPC by mixing calcium phosphate powder (58% alpha-tricalcium phosphate, 25% anhydrous dicalcium phosphate, 8.5% calcium carbonate, and 8.5% hydroxyapatite) with a liquid (3 g/mL). The liquid for standard CPC consisted of water with 4% disodium hydrogen phosphate, whereas the liquid for modified CPC was mixed with an equal amount of 4 mM hydrochloride with 0.2% bovine serum albumin. The hydrochloride liquid contained rhTGF-beta1 in different concentrations for the release experiments. Most of the rhTGF-beta1 incorporated in the cement pellets was released within the first 48 h. For all concentrations of intermixed rhTGF-beta1 (100 ng to 2.5 mg/g of CPC), approximately 0.5% was released in the first 4 h, increasing to 1.0% after 48 h. Further release was only about 0.1% from 2 days to 8 weeks. CPC modification slightly increased the initial setting time at 20 degrees C from 2.6 to 5 min but had no effect on the final setting time of CPC at 20 degrees C or the initial and final setting times at 37 degrees C. The compressive strength was increased from 18 MPa in the standard CPC to 28 MPa in the modified CPC only 4 h after mixing. The compressive strength diminished in the modified CPC between 24 h and 8 weeks from 55 to 25 MPa. No other significant change was found with the CPC modification for rhTGF-beta1. X-ray diffraction revealed that standard and modified CPCs changed similarly from the original components, alpha-tricalcium phosphate and anhydrous dicalcium phosphate, into an apatite cement. The calcium-to-phosphorus ratio, as determined with an electron microprobe, did not differ for standard CPC and modified CPC. Standard and modified CPCs became dense and homogeneous structures after 24 h, but the modified CPC contained more crystal plaques than the standard CPC, as observed with scanning electron microscopy (SEM). SEM and back- scattered electron images revealed that after 8 weeks the cements showed equally and uniformly dense structures with microscopic pores (<1 microm). Both CPCs showed fewer crystal plaques at 8 weeks than at 24 h. This study shows that CPC is not severely changed by its modification for rhTGF-beta1. The prolonged setting time of modified cement may affect the clinical handling but is still within acceptable limits. The compressive strength for both standard and modified cements was within the range of thin trabecular bone; therefore, both CPCs can withstand equal mechanical loading. The faster diminishing compressive strength of modified cement from 24 h to 8 weeks likely results in early breakdown and so might be favorable for bone regeneration. Together with the beneficial effects on bone regeneration from the addition of rhTGF-beta1 to CPC, as shown in our previous studies, we conclude that the envisaged applications for CPC in bone defects are upgraded by the intermixing of rhTGF-beta1. Therefore, the combination of CPC and rhTGF-beta1 forms a promising synthetic bone graft.  相似文献   

14.
Development of macroporosity during setting would allow fast bone ingrowth and good osteointegration of the implant. The interconnected macropores could be created in calcium phosphate cements (CPCs) through the addition of an effervescent porogen mixture to the component of the cements. But this addition could also affect other characteristics of CPCs, such as setting time, mechanical strength, extent of conversion of reactant to apatite phase, crystallinity, and chemical composition of apatite lattice. In this study, these properties were investigated in an effervescent-added calcium phosphate bone cement. From 0 to 20 wt % of an effervescent mixture was added to calcium phosphate cement (CPC) components and phase evaluations were performed after 24 h incubation at 37 degrees C and 28% relative humidity and 1, 3, 7, and 14 days immersion in a specific simulated body fluid. XRD and FTIR techniques were used to characterize the cement composition, crystallinity, and chemical groups in final CPCs. The results showed that addition of effervescent porogen affects the extent of conversion of reactant to apatite phase and crystallinity. In other words, using the effervescent porogen in CPCs could accelerate the rate of conversion of TTCP/DCPA reactant to apatite phase with smaller crystallites, so that it was the predominant phase (about 67%) after only 3 days soaking in SBF solution. The content of carbonate groups substituted for phosphate groups in apatite lattice increased when the effervescent additive was further added. The compressive strength of the set calcium phosphate cement decreased significantly with the addition of the effervescent agent and reached from 8 MPa for additive-free CPC to 1.3 MPa for 20% effervescent-added CPC. The compressive strength was improved after 3 days immersing of CPC in the simulated body fluid solution.  相似文献   

15.
目的:探讨颈中交感神经节阻滞对神经性耳聋的治疗作用.方法:选择神经性耳聋患者90例,并随机分成三组:星状神经节阻滞组(S)、颈中交感神经节阻组(M)及对照组(C),每组各30例.三组均采用中药治疗,M组、S组分别加行颈中交感神经节、星状神经节阻滞治疗,每日1次,10次为1个疗程,2个疗程之间间隔1周.结果:M组、S组60例患者治疗后总有效率分别为90%、86.6%,组间比较差异无统计学意义(P>0.05),但高于C组66.6%(P<0.05).颈中交感神经节阻滞成功率(96.8%)高于星状神经节阻滞(78.7%),且并发症发生率低于后者(P<0.05).结论:颈中交感神经节阻滞联合中医药辨证施治,对神经性耳聋是一种安全、有效、可靠的治疗方法.  相似文献   

16.
Different types of calcium phosphate cements (CPCs) have been studied as potential matrices for incorporating different types of antibiotics. All of these matrices were morphologically microporous whereas macroporosity is essential for rapid cement resorption and bone replacement. In this study, liberation of cephalexin monohydrate (CMH) from a macroporous CPC was investigated over 0.5-300 h in simulated body fluid and some mathematical models were fitted to the release profiles. Macroporosity was introduced into the cement matrix by using sodium dodecyl sulfate molecules as air-entraining agents and the effect of both surfactant and CMH on basic properties of the CPC was studied. Incorporation of CMH into the CPC composition increased the setting time, decreased the crystallinity of the formed apatite phase, and improved the injectability of the paste. The use of both CMH and sodium dodecyl sulfate did not affect the rate of conversion of the reactants into apatite phase while soaking the cements in simulated body fluid. Results showed that the liberation rate of the drug from porous CPC was higher than that of the nonporous CPC but same release patterns were experienced in both types of cements, that is, like to nonporous CPC, a time-dependent controlled release of the incorporated drug was obtained from macroporous CPC. The Weibull model was the best fitting-equation for release profiles of all cements. The liberated CMH was as active as fresh cephalexin. It is concluded that this macroporous CPC can be successfully used as drug carrier with controlled release profile for the treatment of bone infections.  相似文献   

17.
目的:比较在老年肺癌患者行肺叶切除术单肺通气时,两种通气方法对动脉血气值及肺内分流的影响。方法:老年肺癌择期行肺叶切除术患者45例,年龄60~79岁,ASA Ⅰ—Ⅱ级,随机分为3组。A组:对照组;B组:单肺通气时术侧肺行高频喷射通气(HFJV);C组:术侧肺行持续气道正压通气(CAPA)。分别于单肺通气前,单肺通气30min,单肺通气结束,恢复双肺通气30min。测动脉血测血气分析。根据公式计算肺内分流率。结果:单肺通气30min及单肺通气结束时,B、C两组PaO2较A组高,Qs/Qt较A组降低(P〈0.05)。但B、C两组间各时点数据比较差异无显著性。结论:老年肺癌患者行肺叶切除术单肺通气时,术侧肺实施CPAP及HFJV均可明显提高氧分压。减少肺内分流,有临床推广价值。  相似文献   

18.
We investigated the histological and compressive properties of three different calcium phosphate cements (CPCs) using a sheep vertebral bone void model. One of the CPCs contained barium sulfate to enhance its radiopacity. Bone voids were surgically created in the lumbar region of 23 ovine spines - L3, L4, and L5 (n = 69 total vertebral bodies) - and the voids were filled with one of the three CPCs. A fourth group consisted of whole intact vertebrae. Histologic evaluation was performed for 30 of the 69 vertebrae 2 or 4 months after surgery along with radiographic evaluation. Compressive testing was performed on 39 vertebrae 4 months after surgery along with micro-CT analysis. All three CPCs were biocompatible and extremely osteoconductive. Osteoclasts associated with adjacent bone formation suggest that each cement can undergo slow resorption and replacement by bone and bone marrow. Compressive testing did not reveal a significant difference in the ultimate strength, ultimate strain, and structural modulus, among the three CPCs and intact whole vertebrae. Micro-CT analysis revealed good osseointegration between all three CPCs and adjacent bone. The barium sulfate did not affect the CPCs biocompatibility or mechanical properties. These results suggest that CPC might be a good alternative to polymethylmethacrylate for selected indications.  相似文献   

19.
目的:探索不同的打压紧密度对打压植骨转归的影响,以寻求一个定量的指标来指导打压植骨的紧密度。方法:新西兰大白兔30只,其中3只处死后取松质骨制备植骨材料,另外27只随机分成A、B、C3组(n=9),左股骨远端髁部建立腔隙性骨缺损并植骨。植骨紧密度在A组相当于松质骨密度,B组为0.85ρ皮质骨,C组为0.75ρ皮质骨。分别于第4、8、12周每组处死3只试验兔进行x线、骨密度仪检测,大体观察和组织病理切片观察。结果:X线检测,术后12周A组植骨区域密度低于周围正常松质骨组织,和周围松质骨界线较明显,B、C组8周、12周时植骨区域和周围正常松质骨间无明显界线;经过3个月改建,B、C组植骨区和对侧正常松质骨区骨密度差异小。病理观察术后12周C组和A组植骨周围区仍可见骨母细胞(C组多于A组),B组植骨区和周围正常区骨小梁连续,未见骨母细胞。结论:紧密打压植骨有利于移植骨早期改建塑形。当植骨区紧密度为0.85ρ皮质骨时,可以实现紧密打压植骨。  相似文献   

20.
目的:探讨白藜芦醇(resveratrol,RV)对戊四氮(pentylenetetrazole,PTZ)慢性点燃大鼠行为及脑电图(EEG)的影响。方法:将60只Wistar大鼠随机分为空白对照组(A组)、PTZ致癎组(B组)、RV干预组(C组),每组20只。B组和C组通过腹腔注射PTZ建立慢性癫癎动物模型,观察大鼠行为、脑电图及海马组织学变化情况。结果:腹腔注射RV可明显抑制大鼠的癎样放电,延长发作潜伏期、缩短发作时间,与PTZ致痂组相比重型发作率降低(P〈0.05);同时在病理学上还能减轻海马神经元的损伤程度。结论:RV可明显抑制PTZ诱导的大鼠癫癎发作,对致癎海马神经元有一定的保护作用。  相似文献   

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