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Objective: To investigate the effect of autocontrol micromotion locking nail ( AMLN ) on experimental fracture healing and its mechanism. Methods: 16 goats undergoing both sides of transverse osteotomy of the femoral shafts were fixed intramedullary with AMLN and Gross-Kempf (GK) nail, respectively. The follow-up time was 7, 14, 28 and 56 days. Roentgenographic, biomechanical, histological, scanning electromicroscopic and biochemical analyses were done. Results: (1) The strength of anticompression, antiflexion and antitorsion in the fractural end in the AMLN-fixed group was higher than that of GK nail-fixed group; whereas, the rate of stress shelter in the fractured end decreased significantly (P<0.01). (2) The content of the total collagen, insoluble collagen, calcium and phosphate in the AMLN-fixed group was higher than that in the GK nail-fixed group (P<0.05). (3) Histological observation and quantitative analysis of calluses revealed that AMLN could promote the growth of bridge calluses and periosteum calluses. Hence the facture healing and remolding process achieved early, which was much better than traditional GK nail fixation. (P<0.05). (4) 7-14 days postoperation, the calluses of AMLN-fixed group was flourish and camellarly arranged and the collagen fibril formed constantly in the absorption lacuna of bone trabecula. 28-56 days postoperation, the collagen fibril was flourish around the absorption lacuna and was parallel to the bone's longitudinal axis. Active bony absorption and formation were seen, so was remolding and rebuilding. Haversian system was intact and the bony structural net was very tenacious because of the deposition of calcium salt. None of the above findings was observed in the GK nailfixed group. Conclusions: The design of AMLN accords well with the plastic fixation theory. As the geometry ametabolic system constituted by the intramedullary fixation instruments and the proximal and distal end of the fracture is very firm and stable, the disturbance to the physical stress distributed in the fractural end is light. The generation and conduct of the intermittent physical stress between the fractural parts could reach the balance between stress conduct and stress protection. The feature that the healing and remolding take place at the same time speeds up the fractural healing process.  相似文献   
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甲基肿酸锌是有机胂杀菌剂,对水稻纹枯病有较好疗效。为全面了解它在生产中的职业危害及对人类细胞遗传效应,1984年我们调查了某农药厂甲基胂酸锌生产车间的劳动卫生问题及对工人健康影响,现报告如下。方法和结果 (一)生产工艺与劳动条件。某农药厂甲基肿酸锌车间于1972年投产,产品为26%可湿性粉剂,其生产工艺流程:  相似文献   
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抗人生长激素免疫血清的制备和鉴定   总被引:1,自引:1,他引:0  
Using small dosage of human growth hormone to immunize rabbit or guinea pig, it is able to induce anti-hGH antibody formation with high titre and high affinity that could be applied to hGH RIA. In the present study five rabbits and three guinea pigs were immunized with 125-200 micrograms and 250-285 micrograms per animal of hGH respectively, followed by boosters of 10-20 or 160-250 micrograms of hGH at 2-4 week intervals for 6 or 3 months. Blood was drown 1-2 weeks before each booster for determination of antibody formation. Antibody titre and affinity were successively observed and specificity of antibody was determined for the final bleeding. It was shown that titres of immune sera from guinea pigs were much higher than those of rabbit immune sera, but vice versa for antibody affinity. This might be due to larger immunogen dose used for guinea pigs than for rabbits. Fourteen different peptide hormones were tested in reference to cross-immunoreactivity to anti-hGH antibody. It could be demonstrated that the major cross-reactive hormones are hFSH and hLH, and hTSH also reacts to rabbit anti-hGH immune sera at a lesser degree. These cross reactivities are obviously owing to the molecular homogeneities between hGH and these hormones especially of their alpha-subunits.  相似文献   
35.
<正> 肱骨外科颈骨折并肩关节脱位,是一种复杂而严重的创伤,临床上并不多见。其手法整复难度大,目前大多数人主张手术治疗,但术后易并发肩关节功能障碍,如处理不当,可造成严重致残。我科自1985~1990年共收治该病10例,均经闭合手法整复,小夹板外固定治疗,疗效满意。1 一般资料本组共10例,男3例,女7例。年龄最小7岁,最大70岁,平均51岁。病史最短3小时,最长15天,平均6.5天。左侧7例,右侧3例。  相似文献   
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带血管蒂岛状筋膜瓣移植治疗晚期类风湿性髋关节炎   总被引:1,自引:0,他引:1  
目的:阐明带血管蒂岛状筋膜瓣移植治疗晚期类风湿性髋关节炎的疗效。材料和方法:对42例48髋晚期类风湿性髋关节炎病人采用以旋股外侧血管降支为蒂的股前外侧筋膜瓣移植行患髋成形术。结果:术后随访4~10.5年,平均4.5年,髋关节活动范围术前平均16.5°,术后228.6°,按照Charnley和吴之康人工髋关节置换术后的疗效评定标准,优良29髋、很好13髋、好6髋,尚可、差、很差无。结论:患者年龄在15~40岁之间为合适的治疗年龄。与人工髋关节置换术相比,本方法对髋关节正常结构破坏小;一旦手术失败仍可选用其它治疗方法弥补;且并发症少、费用低、远期效果好。  相似文献   
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1994年以来我院儿科用单光子发射计算机断层(SPECT)脑血流灌注显像对73例癫病患儿的结果进行了统计,并作出临床评价。临床资料一、病例资料73例中男42例,女31例。年龄2~6a26例,0~12a47例。大发作56例,小发作8例,头痛性癫痛、腹型癫病各2例,情景性癫病4例,眩晕性癫痛  相似文献   
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