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11.
The etiology of the juvenile type of the human ceroid-lipofuscinosis (JCL) is unknown, in spite of the fact that the first report of this disease was given more than 160 years ago. The necessity of good animal models for scientific progress in chronic metabolic diseases in humans is obvious. The inbred strain of English setter with ceroid-lipofuscinosis (CCL) seems to be a perfect model for human JCL. Dogs with CCL and organs for research purposes are available from Dr. Koppang's experimental kennel in Norway.  相似文献   
12.
IntroductionPRECICE intramedullary magnetic lengthening nails, introduced in 2011, have changed the landscape of long bone limb lengthening. The implants have a stroke ranging from 5 to 8 cm, but it may be desirable to perform part of the lengthening at one treatment, allow bone healing, leave the implant in place, dormant, and then return one or more years later to re-lengthen with the same implant. We call this the “sleeper” nail concept. This strategy may be gentler for the joints and soft tissues. Would the nail mechanism still be functional one or more years later?MethodsWe tested 102 intact, consecutively explanted nails. Using a “fast magnet,” the male part was lengthened to 5 mm short of its maximum stroke capacity and retracted back to 35 mm (all nails start with the male part exposed 30 mm). The nails passed the test if the male part succeeded in lengthening to 5 mm short of the maximum stroke capacity and back to 35 mm (or only retract in case fully deployed at testing). During our testing, the nails were prevented from reaching their full capacity of lengthening/retraction to avoid jamming the gears. Failure was defined as the inability or partial ability to complete the process.ResultsEighty-six nails (84.3%) performed successfully according to our testing standard. When comparing successful and failed nails in terms of nail type, generation, diameter, length and in vivo interval, there was no statistical significance. Comparing both groups in terms of status at testing (fully deployed or not) showed statistical significance with 9 of the 16 failed nails fully deployed at testing (p < 0.001).ConclusionDormant PRECICE nails can be reactivated for further lengthening. The results imply that full deployment may damage the mechanism, making future re-use by retracting and then re-lengthening unsuccessful. The candidate nails for this purpose should not have any signs of clear damage (bending or breakage) and should not have been fully deployed. However, surgeons and patients should be aware of the need for possible nail exchange if the “sleeper” nail fails to wake up.Level of evidenceLevel IV case series analysis of retrieved surgical implants.  相似文献   
13.
使用Edwards套棒可提高Harrington装置对脊柱骨折的解剖复位率,但同时使Harrington棒各点应力值呈线性增加,尤以套棒所在点受影响最大,然而总体应力分布趋势不变,棒体——齿棘区交界处应力集中为棒的危险断面,棒前侧应力值高于后侧;齿棘部高于棒体部。实验结果提示,临床应用Ebwards套捧时应注意将其安置在尽量远离危险断面处,并使危险断面尽量靠近上钩,以减少在交变应力作用下应力集中造成的Harrington棒疲劳断裂。  相似文献   
14.
目的:分析脊柱侧凸鲁氏棒矫形内固定术后内失败的原因,为今后应用鲁氏棒治疗脊柱侧凸提供有益的借鉴。方法回顾1989年1月至1999年3月收治的脊柱侧凸患者应用鲁氏棒矫形内固定者96例,其中由各种原因所致的内固定失败者15例。结果:分析造成内固定失败的原因为①术前软组织松解不充分;②矫形过程中拧紧内固定钢丝时用力不均匀;③内固定钢丝数量太少;④植骨的数量不足;⑤内固定的节段不正确;⑥下床活动太早。结论:应用鲁氏棒治疗脊柱侧凸仍然是一种行之有效的方法,但在术前准备、手术过程和术后处理时,应注意以上可能造成固定失败的因素。  相似文献   
15.
Large skull fractures are conventionally followed radiographically until healing occurs. Fractures which enlarge or remain unhealed are commonly termed leptomeningeal cysts or growing skull fractures. This study of ten children with this injury and a review of the literature shows that a true leptomeningeal cyst is seldom present and that skull fractures do not grow. Moreover, careful history-taking and physical examination will correctly identify all enlarging or unhealed skull fractures of childhood without the need for plain radiographs or computed tomography of the skull.  相似文献   
16.
目的 探讨老年性黄斑变性早期患者黄斑暗视敏感度的变化。方法 用Octopus10 1型视野计 ,对早期老年性黄斑变性组 2 0例 30眼 ,对照组正常人 2 1例 2 6眼进行暗视和明视敏感度检测 ,应用tM2 测试程序 ,将中心 30°视野内视网膜暗视和明视敏感度进行比较和分析。结果 老年性黄斑变性组暗视和明视敏感度较正常组均降低 ,且暗视敏感度降低值大于明视敏感度降低值 ,差异显著 (P <0 .0 5 )。结论黄斑暗视敏感度检测可作为老年性黄斑变性早期诊断和检测指标。  相似文献   
17.
18.
随着社会的不断发展,护理在维护人类身心健康方面发挥了极其重要的作用。但是大量的调查发现临床护士在工作中自我成长需求无法满足,自身价值得不到体现,导致护理人才的流失,进而影响了护理队伍的稳定,这对护理事业的发展十分不利。文章运用马斯洛需要层次理论中的成长型需要分析临床护士的自身发展需求,并针对其现状为护理管理者提供相应的建议,以期更好地满足临床护士的成长需要。  相似文献   
19.
A virtual reality (VR) based vascular intervention simulation system is introduced in this paper, which helps trainees develop surgical skills and experience complications in safety remote from patients. The system simulates interventional radiology procedures, in which flexible tipped guidewires are employed to advance diagnostic or therapeutic catheters into vascular anatomy of a patient. A real-time physically-based modeling approach ground on Kirchhoff elastic rod is proposed to simulate complicated behaviors of guidewires and catheters. The slender body of guidewire and catheter is modeled using more efficient special case of naturally straight, isotropic Kirchhoff rods, and the shorter flexible tip composed of straight or angled design is modeled using more complex generalized Kirchhoff rods. The motion equations for guidewire and catheter were derived with continuous elastic energy, followed by a discretization using a linear implicit scheme that guarantees stability and robustness. In addition, we used a fast-projection method to enforce the inextensibility of guidewire and catheter. An adaptive sampling algorithm was also implemented to improve the simulation efficiency without decrease of accuracy. Experimental results revealed that our system is both robust and efficient in a real-time performance.  相似文献   
20.
为延长生活垃圾集装箱及其零配件的使用寿命,以及解决箱门无法正常开闭和在运输途中的垃圾渗沥液渗漏问题,对部分零部件(扇齿轮、水平杆、兼容箱箱门门框密封技术)进行了技术革新,有效缓解了现存的问题.  相似文献   
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