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41.
目的:研究自体富血小板血浆(PRP)联合骨髓基质干细胞(BMSCs)复合改建脱细胞真皮基质(ADM)修复兔关节软骨的修复效果及临床价值。方法:选择60只股骨髁关节损伤的青紫蓝兔作为研究对象,随机分为研究组、对照组和空白组,各20只。首先制备PRP,再分离BMSCs,并进行体外培养,接种于ADM支架上。研究组培养基添加10% PRP,其他条件同对照组,空白组兔不做任何处理。将BMSCs-ADM复合物植入兔关节缺损处,在1、2、3个月末对构建的软骨组织进行免疫力学、组织学、生物力学检测,比较PRP-BMSCs-ADM联合修复关节缺损的效果。结果:随着培养时间延长,BMSCs的细胞数目显著增多,呈现S形生长曲线,第3天后进入对数期,第9天后进入平台期;从第3天开始,细胞数目OD值研究组均明显高于对照组(P<0.01);随着时间的延长,各组标本软骨样细胞数目增多,软骨陷窝逐渐成熟,软骨表面逐渐光滑,IRCS宏观评分和组织学评分均呈现增长趋势(P<0.01),标本压力弹性模量有上升趋势(P<0.05);同时期研究组标本评分与压力弹性模量均显著高于对照组和空白组(P<0.01);3个月后,研究组软骨缺损修复状况明显优于对照组和空白组。结论:自体PRP联合BMSCs复合改建ADM修复兔关节软骨的修复效果良好,具有可行性。  相似文献   
42.
目的:研究采用脱细胞真皮基质进行引导骨组织再生技术(GBR)并同期种植体植入的短期临床效果。方法29例上前牙脱细胞真皮基质进行 GBR并同期植入种植体,经软组织塑形后,完成最终上部结构。随访3~9个月,对种植体周围软硬组织进行评价。结果29例均获得良好骨整合,种植体无松动脱落。种植体周围软硬组织状态良好,美学效果满意。结论采用脱细胞真皮基质进行上前牙 GBR并同期植入种植体,短期内可获得较满意的临床效果。  相似文献   
43.
44.
目的介绍选择性脱细胞猪皮覆盖大面积烧伤早期创面的研制方法及临床应用效果. 方法 2001年1月~2002年5月,对1例深Ⅱ度15%、Ⅲ度25%烧伤患者的右前臂和右小腿,行选择性脱细胞中厚猪皮早期覆盖.戊二醛交联后表皮面黏贴于容器,边缘包埋.在含0.25%胰酶的PBS液中37℃消化2小时,去污剂处理24小时后,漂洗备用.将处理后猪皮应用于1例切削痂自体微粒植皮创面覆盖约2%,大体和光镜观察其功能和外观恢复情况. 结果组织学观察见表皮层基本完整,真皮内无细胞.初步临床观察显示,选择性脱细胞猪皮的真皮可在创基成活,失活表皮可被宿主自体表皮替代. 结论选择性脱细胞猪皮有望替代现有材料用于大面积烧伤切削痂创面的早期覆盖.  相似文献   
45.
目的 了解微囊化神经组织与脱细胞神经联合移植桥接犬坐骨神经30 mm缺损后腓肠肌的变化.方法 将健康成年杂种犬12只随机分为A、B、C、D 4组(n=3):A组截取双侧坐骨神经行化学萃取制备脱细胞神经;B、C组使用脱细胞神经移植修复犬的坐骨神经30 mm缺损,B组同时辅以微囊化神经组织移植;D组行自体神经移植修复缺损.术后定期观察术侧肢体运动功能恢复情况,6个月时检测神经移植段运动传导速度,并取术侧及健侧腓肠肌行琥珀酸脱氢酶(succinic dehydrogenase,SDH)、突触素和运动终板染色,以及取距远端吻合口以远1 cm的坐骨神经神经行Masson、固蓝及NF-200染色.结果 B、C、D组实验动物均纳入实验动物数量分析、无脱失.图像分析表明B组腓肠肌SDH光密度、肌纤维截面积、突触素及运动终板光密度及面积等与C组有明显统计学差别,而与D组无明显统计学差别,运动功能恢复、电生理及坐骨神经形态学检测均与腓肠肌检测结果相符合.结论 微囊化神经组织细胞与脱细胞神经联合移植修复缺损神经后,重新支配靶器官,使腓肠肌萎缩明显减弱,效果优于单纯脱细胞神经移植,有望代替自体神经移植.  相似文献   
46.
Immunization against pertussis has been re-recommended for healthy children in Germany in 1991. In addition the former restriction of immunizing only in the first 2 years of life was abolished. In children born before 1991 immunization rates against pertussis were 15% or less. With the new recommendations physicians are now faced with an increasing demand of parents for catch-up vaccinations in these children. Since they were immunized against diphtheria and tetanus previously monovalent pertussis vaccines are needed for this indication. Therefore a monovalent, multicomponent acellular pertussis vaccine was studied in 249 German children 15 months to 6 years of age. Three doses were administered at 6–10 week intervals. Reactogenicity and antibody responses against the vaccine antigens pertussis toxin (PT), filamentous haemagglutinin (FHA), 69-kd antigen (pertactin) and fimbriae-2 (agglutinogen) were investigated. Local and systemic reactions were minimal in frequency and severity. Antibody responses against all vaccine antigens were pronounced with 93%–100% of vaccinees demonstrating at least four fold titre rises above pre-immunization after the third dose. These findings indicate that this monovalent, multicomponent acellular pertussis vaccine with excellent immunogenicity and low reactogenicity is an appropriate candidate for closing immunization gaps in older children in countries with previously low vaccination rates against pertussis. Based on the results of this study the monovalent acellular pertussis vaccine was licensed in Germany in January 1994.  相似文献   
47.
This is the report on a prospective, single blind, comparative study of a component acellular pertussis vaccine produced by a combination of detoxified, column purified pertussis toxin (PT) and filamentous hemagglutinin (FHA) combined with diphtheria and tetanus toxoids (DTcaP) and the traditional acellular pertussis vaccine produced with essentially the same method as described by Sato with DT (DTaP) of the same manufacturer. A total of 616 infants and children received DTcaP and a total of 289 received DTaP. In all age groups for both vaccines values of serum antibodies to PT and FHA after two doses of the vaccines were comparable to those of convalescent sera. Incidences of systemic and local reactions were, in general, not greatly different between DTcaP and DTaP recipients. In Japan the use of traditional acellular vaccines replaced whole cell vaccines in 1981. Protective antigens of Bordetella pertussis have now been specified and thus component vaccines have become theoretically possible. This is the first component vaccine which has been developed in Japan. Several other component vaccines are now under investigation in the world.  相似文献   
48.
BACKGROUND: Epidermolysis bullosa (EB) is an acquired disease or inherited as either autosomal dominant or recessive with an incidence of 1/50,000. The prominent clinical characteristic of the disease is the development of bullae or vesicles in mucosa or skin in response to minor trauma. AIM: A female patient with a dystrophic type of EB had been put in a maintenance regimen after completion of the initial phase of periodontal therapy and followed for 7 years. The purpose of this report is to document acellular dermal matrix allograft application to increase the width of the attached gingiva in this patient experiencing difficulty in chewing and performing plaque control due to the dramatic loss of attached gingiva after 7 years of supportive periodontal therapy. METHODS: Under local anaesthesia and antibiotic coverage, the acellular dermal matrix allograft was applied in the anterior region of the upper jaw in order to increase the width of attached gingiva, thereby improving patient comfort. RESULTS: The healing was uneventful and a significant gain in attached gingiva dimensions was observed 9 months after the periodontal surgery. The procedure avoided a second surgical site, provided satisfactory results from an aesthetic point of view, and improved patient comfort. CONCLUSION: Acellular dermal matrix allograft may be regarded as an alternative in the treatment of EB cases to increase the width of attached gingiva and facilitate maintenance of the dentition.  相似文献   
49.
To overcome the problems of limited donor nerves for nerve reconstruction, we established nerve grafts made from cultured Schwann cells and basal lamina from acellular muscle and used them to bridge a 2-cm defect of the rat sciatic nerve. Due to their basal lamina and to viable Schwann cells, these grafts allow regeneration that is comparable to autologous nerve grafts. In order to enhance regeneration, insulin-like growth factor (IGF-I) was locally applied via osmotic pumps. Autologous nerve grafts with and without IGF-I served as controls. Muscle weight ratio was significantly increased in the autograft group treated with IGF-I compared to the group with no treatment; no effect was evident in the tissue-engineered grafts. Autografts with IGF-I application revealed a significantly increased axon count and an improved g-ratio as indicator for "maturity" of axons compared to autografts without IGF-I. IGF-I application to the engineered grafts resulted in a decreased axon count compared to grafts without IGF-I. The g-ratio, however, revealed no significant difference between the groups. Local administration of IGF-I improves axonal regeneration in regular nerve grafts, but not in tissue-engineered grafts. Seemingly, in these grafts the interactive feedback mechanisms of neuron, glial cell, and extracellular matrix are not established, and IGF-I cannot exert its action as a pleiotrophic signal.  相似文献   
50.
异种角膜脱细胞基质和几丁糖载体构建角膜基质层的比较   总被引:3,自引:0,他引:3  
傅瑶  陈苹  范先群 《眼科研究》2006,24(6):561-564
目的探索异种角膜脱细胞基质和几丁糖为载体构建生物角膜组织的可行性,评价二者的结构、功能和生物相容性。方法l%TritonX-100及冷冻干燥处理获得猪角膜脱细胞基质,网状几丁糖材料制备成似角膜片状形态,将体外培养的兔角膜基质细胞种植于两种载体,体外培养2周,形成细胞载体复合物。对构建的角膜组织进行苏木精-伊红染色、扫描电镜观察;同时将两种生物材料移植到兔角膜基质囊袋内,观察其生物相容性。结果角膜基质细胞在两种载体上皆可黏附生长,并分泌细胞外基质。脱细胞基质载体内细胞形态不规则,位于胶原板层间,形成类似正常组织的角膜基质结构;细胞可在几丁糖网状纤维上黏附并包绕生长。两种载体移植到兔角膜囊袋后,脱细胞基质降解较慢,与宿主角膜组织相融性良好,未发生明显排斥及毒性反应;几丁糖载体降解较迅速,但降解产物诱导较严重的排斥反应。结论异种角膜脱细胞基质保留正常组织的胶原板层结构,并具角膜的韧性和良好的生物相容性,更适于作为体外构建生物角膜的载体,而几丁糖材料则需要在构成结构和性能等方面进一步改进.  相似文献   
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