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41.
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   
42.
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   
43.
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   
44.
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   
45.
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   
46.
Objective: To study the biomechanical feature of a newly designed cervical vertebra internal fixation device and its clinical applications. Methods: Some functional spinal units were fixed respectively with titanium plate, fusion cage and new device designed by ourselves, then a controlled biomechanical study including flexion, extension, torsion and lateral bending was performed and the results were analyzed. Results: As to the mechanical performance, fusion cage showed poor performance in extension test and so did the titanium plate in the distortion test. However, the new device showed good performance in every test. Conclusion: Both simple titanium plate fixation and simple fusion cage fixation have biomechanical defaults, but they are complementary. The titanium plate-interbody fusion cage avoids the defaults and has specific advantages.  相似文献   
47.
目 的 探 讨 B、C 型 踝 关节 骨折 的 较佳 治疗 方 法。方 法 本 组 32 例 ,其 中 B 型骨 折 17 例,C 型 骨折 15 例 ,先 将 腓 骨 切开 复 位 AO 钢 板 内固 定 ,再 将 内 踝 骨折 切 开 复 位拉 力 螺 钉 内固 定 ,注意 联 合 韧 带 的 修 补 ,术后 早期 功 能锻 炼。 结 果 32 例 中 29 例 随访 4 个 月~4 年,疗效 优良 27 例 ,尚 可 2 例,无 一 例 疗效 差 。 结 论 B、C型 踝 关 节骨 折 均 需 手术 切 开 复 位,而 AO 钢 板加 螺 钉 固 定牢 固 ,有利 于 术 后 早 期功 能 锻 炼 ,有 利 于 踝 关 节 功 能 的恢 复。  相似文献   
48.
应用锁骨钩钢板治疗Tossy Ⅲ型肩锁关节脱位   总被引:1,自引:1,他引:0  
目的探讨锁骨钩钢板治疗TossyⅢ型肩锁关节脱位的临床疗效。方法我们对2003年2月~2007年1月间52例TossyⅢ型肩锁关节脱位的患者均采用锁骨钩钢板复位内固定治疗。所有患者均未进行喙锁韧带缝合修复,但缝合损伤的肩锁关节囊及韧带和三角肌、斜方肌附丽。6~9个月后取出内固定。按Lazzcano法评定肩关节功能。结果52例患者得到随访,随访9~12个月,平均10个月。肩关节功能,取内固定前:优40例,良10例,差2例,优良率96%;取内固定后:优45例,良7例,差0例,优良率100%。肩关节功能取内固定前为良或差的病例在取出内固定后均有不同程度的改善。无切口感染、内固定松脱或断裂及再脱位等并发症。结论锁骨钩钢板是治疗TossyⅢ型肩锁关节脱位的最好治疗方法,具有操作简单,手术时间短,创伤小,可保证百分百复位,固定可靠,符合肩锁关节的生物力学要求,术后可早期功能锻炼,功能恢复好等特点。  相似文献   
49.
ObjectiveTo analyze the use of packed red blood cells (PRBCs) for patients with pelvic fracture and evaluate factors associated with PRBC transfusion for patients with pelvic fracture.MethodsThis retrospective cohort study collected 551 patients with pelvic fractures from six hospitals between September 1, 2012, and June 31, 2019. The age span of patients varied from 10 to 95 years old, and they were classified into two groups based on high‐energy pelvic fractures (HE‐PFs) or low‐energy pelvic fractures (LE‐PFs). The study''s outcome was the use of PRBCs, fresh frozen plasma (FFP), and albumin. Demographic data, characteristics, laboratory tests, clinical treatment details, and clinical outcomes were compared between the two groups. Factors that were statistically associated with perioperative PRBCs in univariate analyses were included to conduct an optimal scale regression to determine the independent factors for perioperative PRBCs.ResultsA total of 551 patients were screened from six hospitals, and after inclusion and exclusion, 319 were finally included and finished the follow‐up from admission to discharge, while four patients died during hospitalization. Three hundred and nineteen patients were classified into two groups by their injury mechanisms. A total of 230/319 (72.1%) patients were classified into the HE‐PF group, and 89/319 (27.8%) patients were classified into the LE‐PF group. Patients in the HE‐PF group were transfused with 4.5 (3–8) units of PRBCs, 300 (0–600) ml of FFP, and 0 (0–30) g of albumin, while patients in the LE‐PF group were transfused with 3.5 (2–4.5) units of PRBCs, 0 (0–295) ml of FFP, and 0 (0–0) g of albumin (all P < 0.001). There were higher proportions of male patients and patients under 65 in the HE‐PF group (all P < 0.001). HE‐PF group patients were more severely injured and likely to take external fixation. The optimal scale regression revealed four significant factors associated with perioperative transfused PRBCs, which were patients on admission with hemorrhagic shock (importance = 0.283, P = 0.004), followed by fracture types identified by Tile classification (importance = 0.156, P < 0.001), hemoglobin levels below 70 g/L on admission (importance = 0.283, P = 0.004), followed by fracture types identified by Tile classification (importance = 0.156, P < 0.001), hemoglobin levels below 70 g/L on admission (importance = 0.148, P = 0.039), and methods of pelvic fixation (importance = 0.008, P = 0.026), ranked by the importance.ConclusionPatients with HE‐PFs had increased transfusions of PRBCs, FFP, and albumin, and hemorrhagic shock on admission, Tile classification, Hb levels, and stabilization methods were found to be associated with perioperative PRBCs.  相似文献   
50.
ObjectivesTo compare the biomechanical performance of proximal femoral nail anti‐rotation (PFNA), the “upside‐down” less invasive plating system (LISS), and proximal femoral locking plate (PFLP) in fixing different fracture models of subtrochanteric fractures.MethodsThirty composite femurs were divided into three equal groups (PFNA, PFLP, and reverse LISS). The implant‐femur constructs were tested under axial compression load (0–1400 N) from models I to IV, which represented the Seinsheimer type I subtrochanteric fracture, type IIIa subtrochanteric fracture with the posteromedial fragment reduced; type IIIa subtrochanteric fracture with the posteromedial fragment lost; and type IV subtrochanteric fracture, respectively. Axial stiffness was analyzed for each group. Each group was then divided into two subgroups, one of which underwent torsional and axial compression failure testing, while the other subgroup underwent axial compression fatigue testing. The torsional stiffness, failure load, and cycles to failure were analyzed.ResultsPFNA had the highest axial stiffness (F = 761.265, p < 0.0001) and failure load (F = 48.801, p < 0.0001) in model IV. The axial stiffness and failure load of the PFLP were significantly higher than those of the LISS (p < 0.0001, p = 0.001). However, no significant difference in axial stiffness was found between models I to III (model I: F = 2.439, p = 0.106; model II: F = 2.745, p = 0.082; model III: F = 0.852, p = 0.438) or torsional stiffness in model IV (F = 1.784, p = 0.187). In fatigue testing, PFNA did not suffer from construct failure after 90,000 cycles of axial compression. PFLP and LISS were damaged within 14,000 cycles, although LISS withstood more cycles than PFLP (t = 3.328, p = 0.01).ConclusionThe axial stiffness of the three implants was similar in models I to III. The biomechanical properties of PFNA were the best of the three implants in terms of axial stiffness, failure load, and fatigue testing cycles in model IV. The axial stiffness and failure load of the PFLP were better than those of the reverse LISS, but PFLP had fewer cycles in the fatigue tests than the reverse LISS.  相似文献   
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