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31.
Nucleus24型人工耳蜗植入后的电极有效性 总被引:1,自引:0,他引:1
目的:随访耳蜗植入后出现蜗外电极或坏损电极的情况,评价人工耳蜗植入后电极的有效性。方法:1998年6月至2002年8月53例Nucleus CI24M型耳蜗植入者,在术中及术后映射调图时进行电极阻抗测试,确定有无电极坏损及其坏损时间。开机时拍摄耳蜗位X线平片,确定电极是否完全植入。分析手术过程和术者经验对电极有效性的影响。结果:电极出现坏损的比例为13.2%,电极在术中插拔两次以上而造成电极坏损的危险度为0.4656。4年累积生存率达96.2%。不完全植入的比例为15.1%,其中又以耳蜗形态异常者居多(7/11)。结论:Nucleus CI24M型植入体在开机1~4年内的可靠性较高。电极序列在术中插拔两次以上,是导致电极坏损的主要原因。患者耳蜗的纤维化、畸形以及术者经验等因素可能导致电极不完全插入。 相似文献
32.
D. Levy D. A. Deporter R. M. Pilliar P. A. Watson N. Valiquette 《Clinical oral implants research》1996,7(2):101-110
It has previously been reported that porous‐coated root form endosseous dental implants, became well integrated when used in the traditional 2‐stage surgical approach. In this study, the placement of the implant in a 1‐stage (non‐submerged)technique was to be explored. Implants were placed in the mandibles of dogs, and 2 designs were used differing only in that one (experimental) had a 3mm transgingival extension, permitting it to be exposed lo the oral cavity from the outset. 12 (3 per animal) non‐submerged implants were placed on I side of 4 beagle dogs and 12 control (submerged) implants were placed contralaterally. All implants were allowed to heal for 6 weeks, after which histological preparations were made. 2 of 12 non‐submerged implants were lost due to post‐operative complications: otherwise, all implants healed uneventfully. Histomorphometric analysis revealed bone‐implant contact, as assessed by absolute bone contact (ABC) and contact length fraction (CLF). to be greater for the submerged design, suggesting that bone healing may be delayed with the non‐submerged approach. As well. at this early stage of healing, for both implant designs, ABC and CLF were significantly greater on proximal than on buccal and lingual aspects. 相似文献
33.
Orbital hydatid cyst is rare. We present a case with CT and MRI, emphasizing the superiority of the latter.
Received: 19 August 1996 Accepted: 9 September 1996 相似文献
34.
J Goldhahn M Reinhold M Stauber C Knop R Frei E Schneider B Linke 《Journal of orthopaedic research》2006,24(5):917-925
The goal of our study was to evaluate two newly developed implant designs and their behavior in terms of subsidence in lumbar vertebral bodies under cyclic loading. The new implants were evaluated in two different configurations (two small prototypes vs. one large prototype with similar load-bearing area) in comparison to a conventional screw-based implant (MACS TL). A pool of 13 spines with a total of 65 vertebrae was used to establish five testing groups of similar bone mineral density (BMD) distribution with eight lumbar vertebrae each. In additional to BMD assessment via dual-energy X-ray absorptiometry, cancellous BMD and structural parameters were determined using a new generation in vivo 3D-pQCT. The specimens were loaded sinusoidally in force control at 1 Hz for 1000 cycles at three load levels (100, 200, and 400 N). A survival analysis using the number of cycles until failure (Cox regression with covariates) was applied to reveal differences between implant groups. All new prototype configurations except the large cylinder survived significantly longer than the control group. The number of cycles until failure was significantly correlated with the structural parameter Tb.Sp. and similarly with the cancellous BMD for three of five implants. In both large prototypes the cycle number until failure significantly correlated with the preoperative distance to the upper endplates. Although the direct relationship between bone structure or density and mechanical breakage behavior cannot be conclusively proven, all the prototypes adapted for poor bone structure performed better than the comparable conventional implant. 相似文献
35.
36.
In vitro characterization of peptide-modified p(AAm-co-EG/AAc) IPN-coated titanium implants. 总被引:1,自引:0,他引:1
Thomas A Barber Lara J Gamble David G Castner Kevin E Healy 《Journal of orthopaedic research》2006,24(7):1366-1376
Interpenetrating polymer networks (IPNs) of poly(acrylamide-co-ethylene glycol/acrylic acid) [p(AAm-co-EG/AAc)] functionalized with an -Arg-Gly-Asp- containing peptide derived from rat bone sialoprotein [bsp-RGD(15)] were grafted to titanium implants in an effort to modulate osteoblast behavior in vitro. Surface characterization data were consistent with the presence of an IPN, and ligand density measurements established that the range of peptide density on the modified implants spanned three orders of magnitude (0.01-20 pmol/cm2). In vitro biological characterization of the modified implants employing the primary rat calvarial osteoblast (RCO) model resulted in the identification of a critical ligand density (0.01相似文献
37.
一种新型人TNFα对人肝癌裸鼠移植瘤的抗瘤作用 总被引:1,自引:1,他引:0
用人肝癌Bel7402瘤株建立了人肝癌裸鼠移植瘤模型,探讨新型重组人TNFa对这种移植瘤的抗瘤作用,结果表明,rhTFaD11a和原型重组人TNFa的抑瘤率在30%左右时,后者后用的活性产闰数是前者的2倍;两者用量相同时,前者的抑产经比后者提高23个百分 相似文献
38.
Oisin R. O'Neill M.D. F.R.C.S.I. Grant Gilliland M.D. Johnny B. Delashaw M.D. Thomas J. Purtzer M.D. 《Surgical neurology》1994,42(6)
The development of more complex and diverse hunting weapons may result in an increase of uncommon forms of penetrating injury to the brain. We present a case of non-fatal transorbital arrow injury to the brain. High velocity projectile injuries merit certain management adaptations from gunshot or low velocity stab wounds. This case highlights the necessity for anterograde removal of the arrow in the direction of its line of trajectory. Early assessment of the patient with cerebral angiography to identify surgically correctable vascular injury is recommended. 相似文献
39.
Dr. Rüçhan Ergün Ali I. Ökten Muammer Yüksel Bülent Gül Çetin Evliyaoglu Fikret Ergüngör Yamaç Taşkin 《Neurosurgical review》1997,20(1):33-37
Hydatid cysts of central nervous system are rare and comprise only 2% to 3% of all hydatid cysts reported. Orbital localization is very uncommon and has been reported less than 1 % of all hydatid diseases. The primary treatment of hydatid disease is surgical. The most important complication of the surgical treatment is secondary hydatidosis due to spillage of the cyst contents. Because of the difficulties of the orbital localization, total extirpation of the cysts without rupture is almost impossible. Preventing spontaneous rupture of the cysts during surgery and postoperative antihelmintic treatment should be taken into consideration in these cases.This study includes four cases who underwent surgery for orbital hydatid cysts. Radiological characteristics, operative technique and postoperative medical therapy are discussed. 相似文献
40.
目的 为提高额颞部除皱术的效果 ,延长有效时间 ,从理论与实际观察探讨额颞部老年化改变形成的原因 ,并采用相应的手术术式进行矫正。方法 肿胀麻醉下 ,通过颞部发际缘切口入路 ,在颞深筋膜浅面剥离 ,内达颞肌前缘及眶外缘 ,下达颧弓上缘 ,后达耳屏前线。额部切口入路在帽状腱膜下剥离 ,下达眶上缘外至颞线后至枕外隆突。口腔内上颊龈沟入路在颧骨及颧弓骨膜下剥离。上述各剥离区域相互贯通 ,最后将颞区皮瓣上提 ,并将颞浅筋膜与颞深筋膜缝合固定。结果 本组共 32例 ,术后眉外侧平均上提 8mm ,鼻唇沟变浅 ,获随访的 7例为术后 3~2 4个月 ,除皱效果满意。结论 本术式旨在通过广泛剥离解除了额颞部皮肤筋膜上提的羁绊 ,同时减少上面部降肌的作用 ,相对增强提肌的作用 ,再辅以筋膜及皮肤上提固定达到除皱的目的 ,效果确实、可靠、安全、持久。 相似文献