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91.
目的 :观察ZMW型环氧乙烷灭菌箱对异体骨材料灭菌效果 ,旨在寻找一种安全、经济的灭菌方法。方法 :清洁条件下取骨 ,制成 0 .5cm× 0 .5cm× 2cm湿润骨材料和干燥骨材料 ,抽取样本 ,用ZMW型环氧乙烷灭菌箱 (15 0L)在不同温度及时间下消毒 ,以环氧乙烷指示胶带是否变色作为灭菌指标 ,样本在消毒前后分别作细菌培养。结果 :不同消毒条件下 ,每批样本均有细菌生长 ,干燥骨材料有菌率高于湿润的骨材料。结论 :ZMW型环氧乙烷灭菌箱不能使异体骨移植材料完全达到灭菌的要求 ,环氧乙烷指示胶带不能作为骨移植材料的灭菌指标 ,干燥可能使细菌的抗环氧乙烷能力增加 ,从而间接的影响了环氧乙烷的消毒效果。 相似文献
92.
骨髓间充质干细胞的分离培养及生物学特性研究 总被引:3,自引:0,他引:3
目的:通过体外细胞的培养方法将骨髓间充质干细胞由骨髓血中分离出来并加以纯化,进一步在体外培养条件下研究其增殖及生长特征,从而为探讨后续利用组织工程学方法修复肌肉骨骼系统组织缺损的可能性提供实验基础。方法:从骨髓血中提取间充质干细胞,体外培养扩增,再以相差显微镜、电镜观察并绘制生长曲线。结果:(1)通过离体培养,可以使体内环境下低丰度的骨髓间充质干细胞实现数目扩增。(2)体外培养条件下骨髓间充质干细胞具有成纤维细胞的生长特性。(3)体外单层培养条件下贴壁生长的骨髓间充质干细胞会出现“返祖现象”。(4)骨髓间充质干细胞内细胞器与其生物活性变化相一致。结论:骨髓间充质干细胞体外培养成功为今后利用自体间充质干细胞通过组织工程学方法修复肌肉骨骼系统的组织缺损提供功能细胞奠定了基础。 相似文献
93.
Hip arthroplasty is a common orthopaedic procedure with proven long-term success and reliable results. A wide range of associated conditions may affect the outcome of the arthroplasty and the surgeon has to keep these in mind when planning the surgery. In this article, such situations are discussed and recommendations are drawn from the evidence available in literature. 相似文献
94.
Mitsuhiro Morita Harumoto Yamada Osamu Hemmi Kyosuke Fujikawa 《Journal of orthopaedic science》2004,9(1):99-102
In acetabular dysplasia of the hip joint accompanied by a giant acetabular bone cyst, rotational acetabular osteotomy may cause serious complications, such as bone necrosis after surgery or fracture of the fragile acetabulum during the operation. In a patient with this condition, we performed a two-stage operation: first, autogenous bone grafting supplemented with hydroxyapatite filling, then rotational acetabular osteotomy (after new bone formation had been assured). Radiographs and CT scans showed favorable fusion of the grafted bone. Some 18 months after the second operation, arthrograms showed no inflow of contrast medium from the articular cavity into the bone cyst region, although this had been observed before treatment. Thus, an effective remodeling of bony congruency was indicated in the mobile acetabulum 5 years after the second operation. This two-stage operation appears to be useful for correcting acetabular dysplasia accompanied by a giant bone cyst and to carry a reduced risk of serious complications, such as deterioration of the articular surface of the acetabulum or necrosis of the translocated acetabulum. 相似文献
95.
藻酸钙凝胶-成骨细胞-骨粉构建工程化骨修复兔颅骨缺损的实验研究 总被引:1,自引:0,他引:1
目的探讨藻酸钙凝胶、成骨细胞、骨粉复合构建的可塑形组织工程骨修补兔颅骨缺损后的形态学变化和成骨效果.方法28只日本大耳白兔,随机分为A(n=20)、B(n=8)两组,手术在兔颅顶骨矢状缝两侧分别各建立一个直径1cm的圆形全层缺损,用两种方法藻酸钙凝胶、成骨细胞、骨粉和藻酸钙凝胶、骨粉分别构建组成可塑形的组织工程骨复合材料,分别填补修复A组兔颅骨左右两侧的缺损,B组为空白对照组,通过大体、组织学、X线观察材料的形态变化、成骨情况,并对X线片和组织学切片进行评分.结果材料植入后,局部未见红肿、积液、渗出等异常反应.①藻酸钙凝胶-成骨细胞-骨粉组修补后12周颅骨缺损基本被硬性组织所修复,镜下见修复材料大多被骨组织替代,骨粉基本被吸收,有块状凝胶残留其中,组织学评分为(5.50±1.00).X线片见兔颅骨缺损处有高密度骨痂影存在,布满整个缺损区,X线片评分为(3.25±0.95).②藻酸钙凝胶-骨粉组修补后12周部分颅骨缺损被硬性组织所修复,镜下见修复材料部分转变成骨组织,骨粉基本被吸收,有凝胶残留其中,组织学评分为(3.25±1.50).X线片见兔颅骨缺损处有高密度骨痂影存在,主要分布在缺损区的边缘部位,X线片评分(2.25±0.25).③空白对照组骨缺损主要被膜样纤维组织修复,在紧邻骨缺损边缘处有硬性组织形成,镜下见修复组织边缘有骨组织存在,中央大部为膜状致密纤维组织,组织学评分为(1.50±0.50),X线片仅见靠近骨缺损边缘的部位存在致密骨痂影,X线片评分为(1.00±0.57).结论藻酸钙凝胶、成骨细胞、骨粉构建的可塑形组织工程骨可根据颅骨缺损的形态进行塑形填补,在体内有良好的成骨能力,可达到对兔颅骨缺损的骨性修复,但部分藻酸盐凝胶吸收缓慢,手术后12周仍不能满意吸收. 相似文献
96.
F. M. Ulivieri L. P. Piodi G. Marotta D. Marchelli C. Commadini L. Parravicini C. Verdoia P. Gerundini 《Journal of orthopaedics and traumatology》2006,7(4):192-194
Osteoprotegerin (OPG) is a protein that inhibits of osteoclastogenesis. The aim this study was to evaluate the response of
serum OPG levels to neridronate treatment in patients with Paget's disease of bone resistant to previous therapy. Nine patients
(4 men) affected by active Paget’s disease of bone (6 polyostotic, 3 monostotic) not responsive to clodronate were studied.
Serum OPG, osteocalcin, total and bone isoenzyme of alkaline phosphatase (AP and BAP, respectively), and urinary deoxypyridinoline
(DPD) were measured before and 5 months after neridronate treatment (100 mg/day, i.v. for two days). A scintigraphic activity
index (SAI) was also calculated before treatment. Mean baseline OPG levels were within normal values and were not significantly
different 5 months after neridronate treatment. In contrast, there were significant reductions in AP (41.9%, p<0.02) and BAP (38.8%, p<0.04). Serum OPG levels correlated with DPD (r=0.925) and SAI (r=0.689). Although OPG is an important regulator of bone metabolism,
in our series of already treated patients it was not a sensitive marker for diagnosing Paget's disease and for monitoring
the response to pharmacological treatment, whereas AP and BAP confirmed their clinical usefulness. This preliminary study
requires confirmation by a study with a larger population. 相似文献
97.
目的:探讨不同培养阶段骨髓基质干细胞成骨能力的变化及BMP-2对其成骨能力的影响。方法:培养兔骨髓基质干细胞,测定第3代和第18代细胞碱性磷酸酶及骨钙素活性;测定BMP-2对不同培养时间骨髓基质干细胞成骨能力的影响;测定rhBMP-2对细胞增殖的影响。结果:细胞传至第18代后,分泌的骨钙素(OC)水平及ALP活力明显降低,与第3代细胞相比,差异显著(P〈0.05)。第3代细胞在rhBMP-2的诱导下,分泌的OC水平及ALP活力在原基础上进一步升高,与对照组相比,差异显著(P〈0.05)。结第18代细胞在rhBMP-2的诱导下,分泌的OC水平及ALP活力在原基础上升高,与对照组相比,差异不显著(P〉0.05);随培养时间的延长,各组细胞数量均有所增加,rhBMP-2诱导组与对照组细胞无显著性差异(P〉0.05)。细胞的传代次数对细胞增殖无明显影响(P〉0.05)。结论:rhBMP-2对细胞增殖无影响。随着传代次数的增加,骨髓基质干细胞的成骨能力下降,rhBMP-2促进其成骨的能力亦下降。 相似文献
98.
99.
应用显微外科技术治疗脊髓型颈椎病疗效分析 总被引:4,自引:0,他引:4
目的:探讨应用显微外科技术治疗脊髓型颈椎病的方法及疗效。方法:2003年1月~2004年10月对39例脊髓型颈椎病患者经颈前入路应用显微外科技术切除椎间盘、突出的髓核及骨赘.全部操作均在显微镜(10x)放大监视下应用高速磨钻、显微器械、1mm枪式椎板咬骨钳及微型刮匙配合进行。充分减压后作自体髂骨移植及钛板固定。结果:术中失血量平均每节段为80ml,术后咽喉部牵拉反应较轻.无并发症,33例患者术后症状即刻改善,2例术后3个月开始改善,4例术后6个月症状改善。无神经症状加重病例。经12~24个月随访,JOA评分由术前平均9.5分增加至13.4分,平均改善率为75.6%,影像学证实减压充分。椎体间植骨均愈合良好。结论:经颈前路应用显微外科技术治疗脊髓型颈椎病可明显提高组织分辨能力,操作精细.手术创伤小.提高了手术的安全性.疗效确切。 相似文献
100.
A quantitative assessment of cross-sectional cortical bone remodeling in the femoral diaphysis following hip arthroplasty was made by direct in vitro measurements of cross-sectional geometric properties. We obtained eight femora from four female cadavers ranging in age from 77 to 96 years. In three cases unilateral uncemented Austin Moore implants were used, and in one case a unilateral cemented Thompson prosthesis had been implanted. The time of implantation in the two specimens where this information could be obtained was greater than 40 months. Sections were made at 12 diaphyseal locations from the superior aspect of the lesser trochanter through the distal diaphysis. Section properties (areas and second moments of area, or area moments of inertia) were determined by tracing photographs of the cross-sections with a digitizer. In this sample of prosthetic femora, we found reductions in both total subperiosteal area (TA) and endosteal area (ENDA) relative to the contralateral unoperated side in most sections distal to the lesser trochanter. The average pairwise reduction in ENDA for this region was 21.1 mm2, reaching statistical significance in one distal diaphyseal section. The average decline in TA in this region was 10.2 mm2. Because the reduction in endosteal dimensions was generally greater than the reduction in subperiosteal dimensions, cortical area (CA) was maintained or increased throughout the distal 80% of this region in prosthetic femora with an average increase in CA of 9.3 mm2, reaching statistical significance in one mid-diaphyseal section. A completely different pattern of remodeling occurred in the two most proximal sections through the lesser trochanter and base of the femoral neck.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献