Preservation of the non-rectangular cuticular plate/cell axis angle of outer hair cells

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.     

Formation of “neo-cortex” in a congenital human teratoma

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.     

Growth plate injury of the long bones in treated β-thalassemia

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.     

关节－干骺端软骨细胞移植修复兔桡骨缺损

目的研究组织工程软骨移植于成年兔桡骨缺损后的生长、分化与转归特点,以及引导性骨再生和骨缺损的修复机制。方法取自一日龄新生兔关节－干骺端复合物的软骨细胞在几丁质纤维网中增殖21d后装入硅胶管内,套接在成年兔桡骨干1cm的缺损处（实验组12只）;对照组10只在缺损处套接空硅胶管,2只仅填入裸几丁质纤维。术后4周两组各处死3只动物取材,其余在术后16周取材。结果实验组术后4周3只动物的工程软骨组织在骨缺损内形成软骨样组织,术后16周9只动物中有2只动物的缺损愈合。对照组术后4周已开始骨愈合,术后16周9只动物的骨缺损全部愈合。结论新生兔关节－干骺端复合物的软骨细胞在成年兔桡骨缺损区（套管内）未肥大钙化,未再现软骨内化骨过程。缺损内的工程软骨可能因占据空间、阻碍成骨成分进入而中断了骨缺损修复过程。引导性骨再生的机制可能是人工膜管加强了骨膜的天然引导作用而促进了骨愈合。     

颈椎前路带锁钛钢板内固定并发症相关研究

目的分析颈椎前路带锁钛钢板内固定术并发症产生的原因,并提出预防及治疗措施。方法随访58例使用颈椎前路带锁钢板内固定后的颈椎创伤患者,对其并发症产生的原因进行分析,并提出预防及治疗措施。结果58例患者中有11例出现螺钉误入椎间隙、喉上或喉返神经损伤、钢板偏斜、钢板螺钉松动脱出、颈椎生理曲度减少等5种并发症,均采取相应的治疗措施。结论熟悉颈椎的解剖特点,熟练手术技术,术中必要的X线监测,了解颈椎及其内固定器械的生物力学可以减少或避免并发症的发生。     

颈椎前路内固定钢板系统的结构分析与应用

分析了几种颈椎前路内固定钢板系统在结构设计上的特点,以期对颈椎前路内固定钢板系统的临床应用以及研制和设计适合国人的颈椎前路内固定钢板系统提供参考.     

AF系统治疗胸腰椎骨折66例疗效分析

目的:分析AF内固定系统治疗胸腰椎骨折脊髓损伤的疗效。方法:采用AF内固定系统治疗胸腰椎骨析66例,胸椎8例,腰椎58例。其中20例合并不同程度的脊髓损伤,行椎板减压脊髓探查术。结果:被压缩的椎体前缘高度,术后均恢复到90%以上,椎管扩大,术后神经功能恢复较满意。结论:AF内固定系统配合椎板减压是治疗胸腰椎骨析有效方法之一。     

IP板对CR影像质量影响探讨

IP板是CR影像系统的重要组成部分,本文通过我院近几年由于IP板原因产生影像质量问题的各种原因分析,探讨如何正确使用IP板,提高CR的影像质量.     

小切口旋转塑形钢板内固定治疗锁骨骨折

[目的]探讨锁骨骨折的治疗方法和疗效。[方法]应用小切口旋转塑形钢板内固定治疗锁骨骨折27例。[结果]优良27例。[结论]小切口旋转塑形钢板内固定治疗锁骨骨折具有美观、牢固、可以早期进行功能锻炼的优点,是治疗锁骨骨折的一种较好的方法。     

丙磺舒对阿莫西林在家兔体内的药动学影响

目的:观察丙磺舒对阿莫西林在健康家兔体内药动学的影响.方法:采用微生物杯碟法测定兔血清中阿莫西林的浓度.结果:阿莫西林单剂量肌内注射后,吸收迅速,Tmax=(0.78±0.09)h,Cmax=(0.87±0.30)μg·mL-1,其代谢模型为一级速率一房室模型.当阿莫西林和丙磺舒等剂量伍用时丙磺舒对阿莫西林药动学参数的影响达到最大值:阿莫西林的t1/2由(2.06±0.09)h延长至(5.50±0.52)h,AUC由(4.07±0.05)μg·mL-1·h增加至(13.75±3.09)μg·mL-1·h,Cmax由(0.87±0.30)μg·mL-1增加至(6.30±1.46)μg·mL-1,且三者统计学差异极显著(P<0.01).结论:丙磺舒对阿莫西林的药动学参数的影响呈S型,当两者等剂量伍用时影响最大.