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51.
目的 总结可吸收内固定材料自身增强聚丙交脂(SR-PLLA)的临床应用体会。方法 采用波兰进口SR-PLLA螺钉、棒、线治疗四肢松质骨骨折22例,随访摄片观察骨折愈合情况,检查关节活动功能。结果 术后有两侧出现并发症,一例局部少量积液,经2次穿刺抽液加压包扎痊愈;一例患者过早去除石膏功能锻炼,螺钉松动滑出,经手术复位石膏外固定治愈,无感染或过敏等情况发生。结论 掌握可吸收材料的生物力学特点,并选择适当的病例,可以最大限度地发挥可吸收内固定材料的优势。  相似文献   
52.
There are numerous surgical procedures now available to manage bilateral abductor paralyses of the vocal folds. These procedures have various success rates but mostly do not offer reliable and predictable postoperative results, and usually require ,tracheotomy. The technique described in this report is based on a trial study to obtain a safe airway for an affected patient and avoid tracheotomy, if possible. Submucosal cordectomy was used with lateral fixation of one vocal fold and preservation of the arytenoid. The procedure was performed by using continuous intravenous anesthesia, which does not require intubation of the patient's airway. Seven patients were operated with this technique with excellent postoperative results. The glottal airway was largely improved in all patients, with only minor temporary complications.  相似文献   
53.
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   
54.
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   
55.
从1972年11月到1994年3月,401例髋臼骨折病人中的99例经手术治疗并获随访,包括30例双柱骨折,13例横骨折伴后壁骨折,9例后壁骨折,9例后柱骨折,9例前往骨折伴前壁骨折,13例T形骨折和16例横骨折.平均随访时间为7年(2~14).外科手术入路的选择,后入路53次,髂腹股沟入路23次,延长的髂股骨入路11次,放射状入路9次和结合性入路6次.复位情况用X线平片来评判,解剖复位的有59例(59.6%),接近解剖复位(<2mm的错位)的有19例(19.2%).总结果用Harris Hip Score来评判,优秀的有53例(53.5%),良好的有25例(25.3%),一般的有14例(14.1%),差的有7例(7%).并发症中,有10例(53%)为感染,7例(37%)为静脉栓塞.这些结果表明,对于错位严重的髋臼骨折,切开复位内固定是一种可以选择的治疗方法.  相似文献   
56.

Objects.

Myocardial revascularization is performed preferentially with internal mammary artery grafts. Pedicle preparation and pharmacologic vasodilatory treatment vary greatly. Objective measurements are difficult since peripheral and later coronary vascular resistance and possible competitive flow of the native bypassed coronary artery will influence the results significantly. Our objectives were: (1) measurement of internal mammary artery graft flow with the transit-time flow technique; (2) comparison of two surgical take-down techniques (skeletonizing vs standard pedicle preparation); (3) quantitation of transit-time flow compared to the free pedicle flow and (4) the vasodilatory effect of papaverine on internal mammary artery flow.

Method.

Consecutive elective cases of coronary artery bypass grafting, performed by two surgeons using routinely either skeletonizing of the internal mammary artery (group A, n=10) or classical pedicle preparation technique (group B, n=10), were studied prospectively. Anesthesia, cardiopulmonary bypass and operative data were otherwise comparable; likewise, hemodynamic parameters showed no statistical differences between the two groups. Transit-time flow (CardioMed, Medi-Stim, Norway) was measured at the following time points: beginning (1) and end of take-down (2); after papaverine soaking: before (3) and on cardiopulmonary bypass (4); free flow into a beaker (5); after anastomosis; on (6) and off cardiopulmonary bypass (7).

Results.

Measurement of mean flow showed the following results: (1) severe vasoconstruction of the internal mammary artery was detected in both groups regardless of the preparation technique (occurring earlier in group A); (2) papaverine soaking caused a moderate flow increase (up to 40%); (3) with corresponding cardiopulmonary bypass flow (4.4 vs 4.1 l/min in group B) a higher free flow in group A was evident (67.7 vs 50.7 ml/min); (4) after coronary grafting, transit-time flow showed no significant differences between the two groups and (5) using a 3 mm probe, a linear correlation was demonstrated between transit-time flow and simultaneously measured free flow (r=0.89).

Conclusion.

Intraoperative transit-time flow measurement is a reliable method for assessing internal mammary artery and coronary artery bypass flow; considering the simple technical application, the procedure may be regarded as a valuable instrument of quality control.  相似文献   
57.
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   
58.
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   
59.
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   
60.
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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