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71.
动力加压髁螺钉治疗股骨髁部骨折临床与实验研究   总被引:1,自引:0,他引:1  
本研究结合14例股骨髁间、髁上骨折以动力加压髁螺钉(Dynamic Condylar Screw DCS)固定。目的:为临床提供应用DCS的实验数据。方法:采用成人新鲜尸体股骨髁部标本,按照AO/ASIF分类,模拟Y形骨折模型,以DCS固定,置于WD-10E万能电子力学实验机上其抗拉伸、抗扭转、抗村缩、抗剪切强度。结果:DCS有较好的固定强度。临床应用14例,随访6个月至1年,优良率为85.71%。结论:DCS适合于  相似文献   
72.
Motile properties of outer hair cells (OHCs) may contribute to sharp tuning and amplification in the mammalian cochlea. Shape changes of isolated OHCs in response to various physical and chemical influences have been investigated intensively. However, determinations of shape may have been influenced by unanticipated effects of preparation and preservation of the OHCs investigated. Thus, in a first step, lengths of freshly isolated OHCs from the guinea pig cochlea were determined using a video-enhancing magnification system. The cuticular plate/cell axis angle (CP/CA angle) was then measured in native cells and under the influence of potassium chloride and potassium gluconate incubation. To show the influence of glutaraldehyde (GA) fixation on the isolated OHCs, fixative dependent changes on cell length and CP/CA angle were recorded in native and preincubated OHCs. In these experiments, the cell length of vital isolated OHCs was between 41.5 m, in the basal turn, and 103.7 m, in the apical turn. The average CP/CA angle was 106° ± 4.2° (n = 324 cells, turns 1–4) with no statistically significant differences for the four turns. Under the influence of potassium chloride, cell length was reduced by 8.1%. Potassium gluconate incubation led to a shortening of cell length, followed by a 5.3% increase after 5 min. The CP/CA angle under potassium chloride was decreased (97.0°) and was then increased under the influence of potassium gluconate (110.7°) as a result of cuticular plate tilting. Cell shrinkage after fixation depended on the fixative's osmolarity and on the GA concentration. Increased GA levels amplified cell shrinkage from 34% for hypo-osmolar solutions to 15% in iso-osmolar and 29% in hyperosmolar solutions. The CP/CA angle of native and incubated OHCs was not different from those fixed with GA. The present data provide a rational basis for isolated OHC shape parameters. Moreover, functionally induced changes can be better interpreted when OHCs are influenced by fixatives, as shown in the GA experiments.  相似文献   
73.
Summary A congenital human teratoma contained a neuroectodermal mass with architectonic features similar to those of the normal developing neo-cortex. Surrounding a central cavity, a germinal, an intermediate and a cortical zone were clearly distinguishable from innermost to outermost. Glial fibers coursed radially through the intermediate and cortical zones. In the cortical plate neuronal elements were oriented radially with an inside out gradient of differentiation. Mesothelial tissue covered the outer surfaces of the cortex. Over limited sectors a gap in the integrity of the meso-glial barrier were associated with neuroglial ectopias.The following points are of neurobiologic importance: the formation of the miniature cerebral cortex occurred in the absence of any influence of afferent subcortical fibers. The radial alignment of glial fibers between the germinal pseudostratified epithelium and the outer surface occurred only in sectors of the neuro-ectodermal mass where a neo-cortex was present, and may therefore have been a critical determinant in the formation of the cortical plate. The integrity of the outer glial mesenchymal barrier may be necessary for the normal arrangement of cortical neurons.  相似文献   
74.
75.
In 12 patients affected by thalassemia major who received an intensive transfusion regimen combined with continuous iron chelation therapy (desferrioxamine 50–80 mg/kg daily), radiologic abnormalities of the long bones were observed similar to those observed in rickets and scurvy. These abnormalities were associated with a growth retardation. The pathogenesis of these lesions is uncertain, but probably the toxic effect of desferrioxamine plays an important role in their development. A relative deficiency of vitamins D and/or C cannot be entirely excluded.  相似文献   
76.
Kluger's Fixateur Interne proved to be an excellent tool not only in spinal trauma for repositioning of impacted fractures and transpedicular stabilization of the dorsal column but also in other forms of thoracic or lumbar instability.After spinal tumor excision from a dorsal approach and vertebral replacement with methylmethacrylate additional stability through dorsal fixation was achieved with this device.Spondylodiscitis, symptomatic spondylolisthesis, spinal instability from degenerative disc disease as well as nonunion following previous surgery could be cured using Kluger's internal fixation. Rare complications, i.e. from broken screws or rods (5%) caused no problems, but some patients required a second operation for readjustment of malpositioned screws which were causing pain or neurological deficit.  相似文献   
77.
A new operative technique combining retropublic colpourethropexy with transabdominal internal anterior and/or internal posterior repair for the treatment of genuine stress incontinence (GSI) and genital prolapse is described in 75 cases. The overall success rate in correcting GSI was 92.0%, with a 94.8% success rate in the primary surgical group (n=58) and an 82.4% in the secondary group (n=17). Average follow-up has been 1.31 years (range 6 weeks–6 years). There was a 3.4% incidence of residual prolapse. Nine patients also underwent concomitant colpourethropexy. Overall surgical complications include febrile morbidity 4/75 (5.3%), wound infection 1/75 (1.3%), deep vein thrombosis 1/75 (1.3%) and partial ureteric obstruction 1/75 (1.3%). There were no statistically significant changes in multichannel urodynamic studies preoperatively and at 1 year following surgery. Onethird (2/6) of the GSI failures had low MUCP (<20 cm H2O) prior to surgery and continued so at 1 year follow-up.EDITORIAL COMMENT: Genital prolapse is often present in patients who have GSI. If an operation is performed to correct the GSI, and those areas of weakness in the pelvic support system that are contributing to the genital prolapse are not treated, the genital prolapse will become more severe. In the operation which has been described, the colpopexy sutures will correct any cystourethrocele, and the removal of the wedge of tissue from the anterior superior vaginal wall will correct the cystocele. The removal of the wedge of tissue from the posterior superior vaginal wall will reduce the redundancy of the posterior vaginal fornix, but a culdeplasty of the Moschcowitz or Halban type is recommended to treat or prevent an enterocele and to place the vaginal apex in the hollow of the sacrum. Any coexistent rectocele must always be treated vaginally. If it is not treated, it will appear to be more advanced following elevation of the anterior vaginal wall by retropubic urethropexy and the anterior repair which has been recommended.Genital prolapse is best treated by a vaginal approach. When one must une an abdominal approach, ancillary procedures such as the authors have described should be considered. A bulbous upper vagina is ideal for childbearing but if the apical support system and vaginal wall is weakened it is predisposed to prolapse. If the surgeon, in operating for genital prolapse, which involves the upper vagina, will taper the vaginal apex and support it by obliteration of the cul-desac and shortening and reattachment of the uterosacralcardinal complex, postoperative prolapse will be less likely to recur.  相似文献   
78.
This Capsular Lens (ONG, type IV, to be called O.C.L.) has been developed for routinely performed extracapsular cataract extraction with lens implantation. The fundamental surgical procedure was based on continuing experience with the bimanual aspiration-irrigation technique and system developed by the author in 1971. The biomechanical properties of the asymmetric partly flexible, haptic loops are designed to give tensionfree fixation in two capsular pockets. The plano-anterior position of the lens ensures well-defined irido-lenticular clearance and proper alignment of the convex side with the posterior capsule. Consequently no iridectomy or iridotomy is needed for proper aqueous flow.  相似文献   
79.
马林 《实用中医药杂志》2003,19(12):647-648
目的:评价环抱式接骨板与骨卡环治疗四肢长骨干粉碎性骨折的临床疗效。方法:采用西脉环抱式接骨板与骨卡环治疗四肢长骨干粉碎性骨折50例。结果:50例上下肢骨干粉碎性骨折经1~2年随访,均在术后4个月内愈合,功能恢复良好,无接骨板与骨卡环断裂及再骨折。结论:西脉环抱式接骨板与骨卡环具有形状记忆功能及持续的自动加压功能,固定可靠,骨卡环有良好的辅助固定作用,持续的抱合力使骨折愈合周期缩短。不钻孔.不用螺钉,人为损伤小,操作简便,缩短了手术时间,可用于一些特殊类型的骨折。但该固定器不适用于扁平骨及干骺段等不规则部位骨折。  相似文献   
80.
本研究选取五种不同固定液,分别按四种固定时间(12小时,24小时,48小时和72小时)对存在有HBVDNA的人肝癌组织进行固定,脱水包埋。然后提取组织DNA,观察不同固定液及固定时间对PCR扩增效果的影响。同时,还比较了从蜡块中制取PCR模板的四种方法。结果显示:新配中性缓冲甲醛液对组织DNA破坏较小,对PCR扩增效果影响亦较小且成本费用相对较低,固定时间最好不超过48小时。长期放置的用自来水配制的甲醛固定液对组织DNA破坏较大,DNA降解严重,直接影响PCR扩增效果。在用蜡块组织制备DNA模板上,传统酶消化,酚-氯仿抽提,酒精沉淀较为稳定,但所需组织相对较多。对小块组织,充分脱蜡,用双蒸水充分煮沸是制备PCR模板较简便的方法。根据本研究,笔者建议,在目前我国日常病理工作中,应重视对固定液的选择及固定时间的限制,以便能为进一步基因诊断提供先决条件。  相似文献   
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