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1.
磷酸三钙(β-TCP)生物陶瓷植入兔股骨后植入生物陶瓷,界面和兔股骨的显微红外光谱,对其红外特征频率作了指认和归属,在植入生物陶瓷和界面的红外光谱中,骨骼矿物相(或磷酸钙)胶原,蛋白质和脂类(或磷奚)的红外特征频率同时出现,它民股骨的红外光谱非常相似,其结果与拉曼光谱相互吻合,相互补充,这些光谱数据为揭示β-TCP生物陶瓷的生物降解和新骨生成机理提供了大量分子信息和证据,从而证明生物陶瓷骨内植入后  相似文献   

2.
磷酸三钙(β-TCP)生物陶瓷植入兔股骨后植入生物陶瓷、界面和兔股骨的显微红外光谱,对其红外特征频率作了指认和归属。在植入生物陶瓷和界面的红外光谱中,骨骼矿物相(或磷酸钙),胶原,蛋白质和脂类(或磷脂)的红外特征频率同时出现,它们与股骨的红外光谱非常相似,其结果与拉曼光谱相互吻合,相互补充。这些光谱数据为揭示β-TCP生物陶瓷的生物降解和新骨生成机理提供了大量分子信息和证据,从而证明生物陶瓷骨内植入后不仅陶瓷本身已部分溶解和降解而且在植入陶瓷的表面和孔隙中以及界面处均已生成新生骨组织。  相似文献   

3.
多孔β—TCP生物陶瓷植入兔股骨后的拉曼光谱   总被引:2,自引:1,他引:1  
以514.5nm和632.8nm激光激发,采用显微拉曼光谱和近红外傅里叶变换拉曼光谱分别研究了磷酸三钙(β-TCP)生物陶瓷植入兔股骨后陶瓷、界面和兔股骨的拉曼光谱。对其拉曼光谱特征频率进行了初步的归属,叙述了可见光和近红外光谱的优缺点。在植入区和界面的拉曼光谱中,磷酸钙、胶原、蛋白质和脂类的拉曼特征频率同时出现,说明除磷酸钙外,还含有胶原、蛋白质和脂类,他们是有机骨基质主要组成。实验结果表明,生  相似文献   

4.
2-位硒桥联β-环糊精的合成及催化性质   总被引:2,自引:0,他引:2  
将β-环糊精(β-CD)2位羟基选择性磺酰化后,再用NaHSe处理使谷胱甘肽过氧化物酶(GPX)的催化基团-SeH引入β-CD的2位上,经空气氧化得到了GPX模拟物双硒桥联β-环糊精.利用元素分析、核磁共振、红外光谱对此模拟物进行了表征.X光电子能谱技术测定了模拟物中硒的价态和含量.测活结果表明模拟物的GPX活性是PZ51的7.5倍  相似文献   

5.
以双顺反子表达载体,在大肠杆菌中经IPTG诱导表达了人骨形成蛋白-3羧基端肽段(hBMP-3C),表达量占菌体总蛋白量的18.5%.目的蛋白为25kD、含hBMP-3C端215个氨基酸残基组成的肽段,包括hBMP-3成熟肽和一部分前肽.表达产物以包涵体的形式存在,用含TritonX-100的洗涤液和5mol/L以下脲溶液连续洗涤,可获得较高纯度的重组人骨形成蛋白-3C端肽.经复性处理成可溶性蛋白,植入小鼠肌肉内,第14d组织切片显示有软骨细胞和软骨基质形成,第21d可见成骨细胞和骨基质形成.将rhBMP-3C与脱矿去免疫原性异种骨粒复合后作小鼠肌肉植入试验,21d组织切片上可见硬质骨形成.结果表明:大肠杆菌表达的hBMP-3C经复性后具有诱骨活性,糖基化并非BMP-3活性所必需.  相似文献   

6.
摘要 目的:研究国产多孔钽材料能否在兔胫骨缺损模型中顺利实现骨长入,用于修复胫骨缺损。方法:在36只新西兰大白兔双侧胫骨骨干处建立骨缺损模型,每只动物左右侧缺损随机分组,分别进入实验组(植入多孔坦材料)和对照组(不植入多孔坦材料)。植入后4周、8周和12周取材,通过X线检测以及硬组织切片苏木精伊红染色,检测多孔钽材料与骨界面的骨整合情况。采用推出实验检测多孔钽材料与骨界面的结合强度。结果:将术后不同时间点取得的胫骨标本作X射线拍片分析,4周时,骨缺损端与材料结合部位有骨质生成,在8周时材料表面有骨形成现象,逐渐完全覆盖材料表面,在12周时骨量继续增加,形成覆盖材料并桥接骨缺损断端的骨痂。样本行硬组织切片并行HE染色后检测,植入4周后实验组材料两端被新生骨所覆盖,材料深部的孔隙中也可见少量骨组织长入;植入8周后发现实验组材料与骨组织生长良好,多孔钽材料表面和两端材料孔隙内均有骨组织长入,材料孔隙与组织紧密连接,有骨小梁长入;植入12周时两端骨组织长入深度没有明显变化,但材料表面骨组织继续长入,并完全嵌入圆柱体材料内。材料植入后4周与8周比较差异无统计学意义(P>0.05),材料植入后8周与12周比较差异有统计学意义(P<0.05)。将植入4周、8周和12周后含材料样本置于动态疲劳试验机上进行推出实验,随时间延长所需推出力明显增加,植入后4周和8周相比,虽然后者所需推力较大,但两者比较差异无统计学意义(P>0.05),而8周和12周比较则差异有统计学意义(P<0.05)。结论:国产多孔坦材料能在胫骨缺损中实现与骨整合,能用于皮质骨缺损修复。  相似文献   

7.
人绒毛膜促性腺激素β—亚基在中国仓鼠卵巢细胞中…   总被引:4,自引:0,他引:4  
本文以哺乳动物细胞表达载体pSV2-dhfr为运载体,构建了受控于SV40早期启动子β-hCG基因的表达载体,转染CHO-hfr^-细胞后,挑选CHO(dhfr^+)细胞,结果表明β-hCG不仅在细胞中表达,不分泌到培养液中,通过氨甲喋(MTX)加压后,表达量逐渐提高,0.1μmol/LMTX条件下培养液中β-hCG最高表达量可达到1.5μg/10^6细胞.24小时。经亲和层析获得纯的重组β-hC  相似文献   

8.
目的和方法:将红细胞生成素(EPO)3'-增强子野生片断及点突变片断借脂质体主人脐静脉内皮细胞株ECV-304,用半定量RT-PCR测定正常秘缺氧诱导因子-1(HIF-1)诱导剂氧化钴(CoCl2)作用下培养6h的细胞环氧合酶2(COX-2)和血栓素合酶(TXS)的mRNA。结果:HIF-1诱导剂CoCl2可放COX-2和TXS基因转明显增强2,向细胞导入野生EPO3'增强子片断可阻断CoCl2诱  相似文献   

9.
眼镜蛇毒细胞毒素的抗肿瘤作用   总被引:1,自引:0,他引:1  
王锡锋  曹宜生 《蛇志》1999,11(3):16-20
目的 研究眼镜蛇毒细胞毒素( C V C T X)的体内抗肿瘤作用。方法 小鼠皮下、腹腔接种 S180 、 E A C后, 于接种部位注射不同剂量的 C V C T X, 每天 1 次, 连续10 天, 观察瘤重抑制率和生命延长率。结果 适当剂量(02~08m g/kg) 的 C V C T X 能明显抑制肿瘤的生长 ( P< 001),小鼠的存活时间明显延长( P < 001)。结论  C V C T X 在小鼠体内对 S180 、 E A C有明显地抗肿瘤作用。  相似文献   

10.
本研究考察了崩解剂羧甲基淀粉(CMS)的取代度(DS)和CMS中H/Na(游离羧基和成盐羧基比值)改变对其吸水溶胀性能和崩解性能的影响。并应用红外光谱,X-射线衍射和扫描电镜等方法探求CMS的结构与性能的关系。  相似文献   

11.
This paper presents a numerical model of a porous, hydroxyapatite-based bone graft also suitable as a drug delivery device. The graft was positioned in different sites and with different porosities inside a human femur model. The structural analyses were carried out to verify the graft mechanical strength, using the Tsai–Wu criterion, and the maximum porosity at which static failure does not occur. A local stress shielding risk was also calculated as the ratio between the bone stress in the intact condition and the stress after implantation of the graft. Drug release kinetics was calculated by means of the finite element method. High porosity grafts were found to fail in all implantation sites. Lower porosity grafts showed to have adequate strength if implanted in some positions, while provided insufficient resistance for other implantation sites. Drug release kinetics was found to be strongly dependent both on the porosity of the graft and the bone density near the bone-graft interface.  相似文献   

12.
Bone remodeling simulation is an effective tool for the prediction of long-term effect of implant on the bone tissue, as well as the selection of an appropriate implant in terms of architecture and material. In this paper, a finite element model of proximal femur was developed to simulate the structures of internal trabecular and cortical bones by incorporating quantitative bone functional adaptation theory with finite element analysis. Cementless stems made of titanium, two types of Functionally Graded Material (FGM) and flexible ‘iso-elastic’ material as comparison were implanted in the structure of proximal femur respectively to simulate the bone remodeling behaviors of host bone. The distributions of bone density, von Mises stress, and interface shear stress were obtained. All the prosthetic stems had effects on the bone remodeling behaviors of proximal femur, but the degrees of stress shielding were different. The amount of bone loss caused by titanium implant was in agreement with the clinical observation. The FGM stems caused less bone loss than that of the titanium stem, in which FGM I stem (titanium richer at the top to more HAP/Col towards the bottom) could relieve stress shielding effectively, and the interface shear stresses were more evenly distributed in the model with FGM I stem in comparison with those in the models with FGM II (titanium and bioglass) and titanium stems. The numerical simulations in the present study provided theoretical basis for FGM as an appropriate material of femoral implant from a biomechanical point of view. The next steps are to fabricate FGM stem and to conduct animal experiments to investigate the effects of FGM stem on the remodeling behaviors using animal model.  相似文献   

13.
With particular interest on total hip arthroplasty (THA), optimization of orthopedic prostheses is employed in this work to minimize the probability of implant failure or maximize prosthesis reliability. This goal is often identified with the reduction of stress concentrations at the interface between bone and these devices. However, aseptic loosening of the implant is mainly influenced by bone resorption phenomena revealed in some regions of the femur when a prosthesis is introduced. As a consequence, bone resorption appears due to stress shielding, that is to say the decrease of the stress level in the implanted femur caused by the significant load carrying of the prosthesis due to its higher stiffness. A maximum stiffness topological optimization-based (TO) strategy is utilized for non-linear static finite element (FE) analyses of the femur–implant assembly, with the goal of reducing stress shielding in the femur and to furnish guidelines for re-designing hip prostheses. This is accomplished by employing an extreme accuracy for both the three-dimensional reconstruction of the femur geometry and the material properties maps assigned as explicit functions of the local densities.  相似文献   

14.
This study reports several clinical cases for orthopaedic bone regeneration using an injectable bone substitute (MBCP Gel®) to demonstrate its safe use and efficiency in clinical applications. The biomaterial is a composite of microporous bioceramic hydroxyapatite granules that are associated with beta tricalcium phosphate (MBCP) and a synthetic hydrosoluble polysaccharide hydrogel (CE mark 123 and FDA dental domain registered). The present exploratory study demonstrated the generative osseous performance of this injectable bioceramic for filling various orthopaedic bone defects. The clinical cases showed bone ingrowth into the cavities created by drilling when removing the aseptic osteonecrosis of the femoral head during biopsy taking. Furthermore, bone reconstruction was seen after filling large cystic defects, at the time of the revision surgery of the hip prosthesis. Resorption and bone ingrowth with trabecular bone architecture were observed in defects created in long bones (femur and tibia). Patients were followed during 5 months to 1 year. The overall results demonstrated the safe use and the clinical performance of this injectable bioceramic in orthopaedics.  相似文献   

15.
Microdamage accumulation leads to reduced bone strength and fracture. Intact, damaged and Rose Bengal stained cortical bone specimens were studied using SEM and EDXA imaging. SEM coupled with EDXA studies showed selective labelling of surface damage due to binding of dye at free lattice sites. A series of novel iodinated X-ray contrast agent were synthesised. These agents demonstrated excellent stability, water solubility and lack of atropisomerism. Preliminary imaging studies, using cone-beam mu-CT, demonstrated their ability to provide visible contrast in the solid state on bone surfaces.  相似文献   

16.
Porous calcium phosphate ceramics are used in orthopedic and craniofacial applications to treat bone loss, or in dental applications to replace missing teeth. The implantation of these materials, however, does not induce stem cell differentiation, so suitable additional materials such as porous calcium phosphate discs are needed to influence physicochemical responses or structural changes. Rabbit adipose-derived stem cells (ADSC) and mouse osteoblastic cells (MC3T3-E1) were evaluated in vitro by the MTT assay, semi-quantitative RT-PCR, and immunoblotting using cells cultured in medium supplemented with extracts from bioceramics, including calcium metaphosphate (CMP), hydroxyapatite (HA) and collagen-grafted HA (HA-col). In vivo evaluation of the bone forming capacity of these bioceramics in rat models using femur defects and intramuscular implants for 12 weeks was performed. Histological analysis showed that newly formed stromal-rich tissues were observed in all the implanted regions and that the implants showed positive immunoreaction against type I collagen and alkaline phosphatase (ALP). The intramuscular implant region, in particular, showed strong positive immunoreactivity for both type I collagen and ALP, which was further confirmed by mRNA expression and immunoblotting results, indicating that each bioceramic material enhanced osteogenesis stimulation. These results support our hypothesis that smart bioceramics can induce osteoconduction and osteoinduction in vivo, although mature bone formation, including lacunae, osteocytes, and mineralization, was not prominent until 12 weeks after implantation.  相似文献   

17.
The determination of biomechanical force systems of implanted femurs to obtain adequate strain measurements has been neglected in many published studies. Due to geometric alterations induced by surgery and those inherent to the design of the prosthesis, the loading system changes because the lever arms are modified. This paper discusses the determination of adequate loading of the implanted femur based on the intact femur-loading configuration. Four reconstructions with Lubinus SPII, Charnley Roundback, Muller Straight and Stanmore prostheses were used in the study. Pseudophysiologic and nonphysiologic implanted system forces were generated and assessed with finite element analysis. Using an equilibrium system of forces composed by the Fx (medially direction) component of the hip contact force and the bending moments Mx (median plane) and My (coronal plane) allowed adequate, pseudo-physiological loading of the implanted femur. We suggest that at least the bending moment at the coronal plane must be restored in the implanted femur-loading configuration.  相似文献   

18.
Artificial bone grafting is widely used in current orthopedic surgery for bone defect problems. Unfortunately, surgeons remain unsatisfied with the current commercially available products. One of the major complaints is that these products cannot provide sufficient mechanical strength to support the human skeletal structure. In this study, we aimed to develop a bone scaffold with better mechanical property and good cell affinity by 3D printing (3DP) techniques. A self-developed 3D printer with laser-aided gelling (LAG) process was used to fabricate bioceramic scaffolds with inter-porous structures. To improve the mechanical property of the bioceramic parts after heating, CaCO3 was added to the silica ceramic slurry. CaCO3 was blended into a homogenous SiO2-sol dispersion at weight ratios varying from 0/100 to 5/95 to 9/91 (w/w). Bi-component CaCO3/SiO2-sol was prepared as a biocomposite for the 3DP scaffold. The well-mixed biocomposite was used to fabricate the bioceramic green part using the LAG method. The varied scaffolds were sintered at different temperatures ranging from 900 to 1500°C, and the mechanical property was subsequently analyzed. The scaffolds showed good property with the composite ratio of 5:95 CaCO3:SiO2 at a sintering temperature of 1300°C. The compressive strength was 47 MPa, and the porosity was 34%. The topography of the sintered 3DP bioceramic scaffold was examined by SEM, EDS and XRD. The silica bioceramic presented no cytotoxicity and good MG-63 osteoblast-like cell affinity, demonstrating good biocompatibility. Therefore, the new silica biocomposite is viable for fabricating 3DP bone bioceramics with improved mechanical property and good cell affinity.  相似文献   

19.
Hip resurfacing arthroplasty is an alternative to traditional hip replacement that can conserve proximal bone stock and has gained popularity but bone resorption may limit implant survival and remains a clinical concern. The goal of this study was to analyze bone remodelling patterns around an uncemented resurfacing implant and the influence of ingrowth regions on resorption. A computed tomography-derived finite element model of a proximal femur with a virtually implanted resurfacing component was simulated under peak walking loads. Bone ingrowth was simulated by six interface conditions: fully bonded; fully friction; bonded cap with friction stem; a small bonded region at the stem-cup intersection with the remaining surface friction; fully frictional, except for a bonded band along the distal end of the cap and superior half of the cap bonded with the rest frictional. Interface condition had a large influence on remodelling patterns. Bone resorption was minimized when no ingrowth occurred at the bone-implant interface. Bonding only the superior half of the cap increased bone resorption slightly but allowed for a large ingrowth region to improve secondary stability.  相似文献   

20.
本文综述了生物陶瓷材料研制发展的历史和现状,介绍了生物陶瓷材料在当前临床应用的情况,展望了其应用前景。  相似文献   

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