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991.
Lateral unicompartmental knee arthroplasty (UKA) is a valid alternative treatment in the event of arthritis confined to the lateral compartment. This paper examines its indications, technique and short to medium-term results. A total of 159 Miller–Galante cemented UKA prostheses (Zimmer, Warsaw, Indiana) were implanted consecutively (131 medial and 28 lateral) by the same surgeon. This study investigates 28 lateral UKAs in 27 patients. Twenty-five implants in 24 patients (including a subject operated bilaterally) were followed up for 12–60 months. Three patients were discarded on account of to short a follow-up period. The Hospital for Special Surgery (HSS) knee score was used to compare the pre- and post-operative results of the lateral UKA patients. The HSS score improved from a pre-op mean of 59.92 (range 48–68) to 88.04 (range 71–95) at the last follow-up. There was a positive increase in the pain, function and ROM components of the score. The lateral UKA prosthesis can be regarded as a sound alternative to total knee replacement. Correct patient selection on the basis of optimum surgical indications, however, is essential. No benefits of funds were received in support of the study.  相似文献   
992.
目的:探讨dl-3-正丁基苯酞软胶囊(恩必普软胶囊)治疗慢性脑供血不足的临床疗效及对慢性脑供血不足病人认知功能改善的影响。方法:将60例慢性脑供血不足病人随机分为治疗组和对照组,每组30例,治疗组口服dl-3-正丁基苯酞软胶囊,每次200毫克,每日3次;对照组口服复方丹参片,每次4片,每日3次,疗程为8周,治疗前后进行疗效评价和P300数据采样,同时给予同步MMSE、HDS量表评分。结果:治疗组总有效率为70%,对照组总有效率为53.3%,2组治疗后比较差异有显著意义(P<0.05);治疗组治疗前、后MMSE和HDS量表得分情况比较,均有明显改善(P<0.01),与对照组治疗后比较差异有显著意义(P<0.05);治疗组治疗前、后P300波潜伏期及P300波幅差异均有显著意义(P<0.05),与对照组治疗后比较均有显著差异(P<0.05)。结论:dl-3-正丁基苯酞软胶囊对慢性脑供血不足病人安全有效。  相似文献   
993.
Abstract Alzheimer's disease (AD) is defined pathologically by the presence of β-amyloid plaques, neurofibrillary tangles and extensive neuronal loss. Evidence indicates that increased DNA damage may contribute to neuronal loss in AD. Recently, it has been shown that in AD neurons have a reduced capacity for some types of DNA repair. Polymorphisms in DNA repair genes may be associated with differences in repair efficiency of DNA damage. Variants of several DNA repair genes, including the base excision repair gene XRCC1, have been described previously. We hypothesised that Arg194Trp polymorphism of XRCC1 gene may contribute to genetic susceptibility for AD. In order to test this hypothesis, we investigated Arg194Trp polymorphism at the XRCC1 gene in the DNA samples of 98 patients with AD and 95 healthy subjects. The frequency of the Trp allele was more pronounced among cases (11.2%) compared with controls (5.8%). On combining the homozygous and heterozygous variants of each codon, the variants seemed to be at twofold risk of AD, although the risk estimates were not statistically significant (OR=1.95, 95% CI 0.88–4.34, p=0.09). In addition, the 194Trp allele revealed a borderline significance (OR=2.05, 95% CI 0.96–4.37, p=0.056). According to our results, it may be speculated that the polymorphic variants of XRCC1 codon 194 have a role in the development of AD.  相似文献   
994.
目的 探讨血液透析滤过 (HDF)治疗高钠血症的临床效果。方法 对 16例高钠血症患者行HDF治疗 ,动态观察血清钠以调整置换液成分。结果  16例患者经 2~ 8h连续性静脉 -静脉血液滤过后血钠开始下降 ,6~ 2 8h可降至正常。结论 血液滤过透析治疗高钠血症效果确切 ,安全性好  相似文献   
995.
目的:观察影像学和脑电图对儿童缺氧缺血性脑病的应用对照及意义。方法:对65例缺氧缺血性患儿作影像学和脑电图检查。结果:脑电图正常6例(9.23%),轻度异常13例(22.03%),中度异常37例(61.03%),重度异常9例(16.94%),脑电图异常率为90.77%。脑电图异常表现为弥漫性慢波增多和局限性癎性放电。影像学异常44例,异常率为67.69%。结论:影像学和脑电图检查对儿童缺氧缺血性脑病的诊断及治疗有一定的帮助。  相似文献   
996.
目的:应用磷酸镁骨水泥(magnesium phosphate cement,MPC)粘接固定家兔胫骨平台骨折,探讨其治疗效果、粘接和降解机理。方法:20只家兔分为两组,第1组15只,第2组5只,通过开放截骨法建立家兔双侧胫骨平台骨折模型。第1组:实验组用MPC骨水泥固定,对照组用“L”形钢板固定。第2组:实验组也同样用MPC骨水泥固定,而对照组作空白对照。通过大体观察、影像学、组织学及电解质检查,探讨MPC骨水泥治疗骨折的效果、对体内电解质的影响、粘接和降解机理。结果:6周后实验组都获得稳定的骨折愈合,没有发现骨折错位及延迟愈合,MPC骨水泥逐渐被吸收,对体内电解质无明显影响,其对骨折的治疗和钢板固定组达到同样的治疗效果。而空白对照侧均出现骨折错位、畸形愈合。通过对标本的组织学检查发现其粘接机理为镶嵌固定,并通过溶解而逐步降解。结论:MPC骨水泥具有一定的粘接强度,能降解,对体内电解质干扰小,是一种较为理想的骨水泥,可以用于骨折的粘接固定。  相似文献   
997.
A 48‐year‐old male patient with long‐standing ulcerative colitis since February 2001 which was diagnosed by endoscopy, developed acute digital ischemia affecting both hands with fixed colour changes in the left index finger which was followed shortly by digital ulceration. Magnetic resonance angiography (MRA) of both upper limbs showed evidence of vasculitis affecting digital arterioles on both sided and right subclavian occlusion. The patient received pulse methylprednisolone followed by cyclophosphamide pulse therapy, the latter continuing on a monthly basis for 6 months with appreciable improvement and remission of the vasculitic process; follow‐up MRA showed reperfusion of the previously occluded subcalvian artery. To the authors’ knowledge vasculitis complicating the course of ulcerative colitis is a rare association and is only sporadically reported in the literature. This rare entity should be diagnosed early and aggressively treated; MRA is a very promising diagnostic tool that is suitable for both diagnosis and follow‐up of patients with this rare entity.  相似文献   
998.
Eight-channel transmit/receive body MRI coil at 3T.   总被引:1,自引:0,他引:1  
Multichannel transmit magnetic resonance imaging (MR) systems have the potential to compensate for signal-intensity variations occurring at higher field strengths due to wave propagation effects in tissue. Methods such as RF shimming and local excitation in combination with parallel transmission can be applied to compensate for these effects. Moreover, parallel transmission can be applied to ease the excitation of arbitrarily shaped magnetization patterns. The implementation of these methods adds new requirements in terms of MRI hardware. This article describes the design of a decoupled eight-element transmit/receive body coil for 3T. The setup of the coil is explained, starting with standard single-channel resonators. Special focus is placed on the decoupling of the elements to obtain independent RF resonators. After a brief discussion of the underlying theory, the properties and limitations of the coil are outlined. Finally, the functionality and capabilities of the coil are demonstrated using RF measurements as well as MRI sequences.  相似文献   
999.
1000.
The ability to cluster different perfusion compartments in the brain is critical for analyzing brain perfusion. This study presents a method based on a mixture of multivariate Gaussians (MoMG) and the expectation-maximization (EM) algorithm to dissect various perfusion compartments from dynamic susceptibility contrast (DSC) MR images so that each compartment comprises pixels of similar signal-time curves. This EM-based method provides an objective way to 1) delineate an area to serve as the in-plane arterial input function (AIF) of the feeding artery for adjacent tissues to better quantify the relative cerebral blood volume (rCBV), relative cerebral blood flow (rCBF), and mean transit time (MTT); 2) demarcate regions with abnormal perfusion derangement to facilitate diagnosis; and 3) obtain parametric maps with supplementary information, such as temporal scenarios and recirculation of contrast agent. Results from normal subjects show that perfusion cascade manifests (in order of appearance) the arteries, gray matter (GM), white matter (WM), veins and sinuses, and choroid plexus mixed with cerebrospinal fluid (CSF). The averaged rCBV, rCBF, and MTT ratios between GM and WM are in good agreement with those in the literature. Results from a patient with cerebral arteriovenous malformation (CAVM) showed distinct spatiotemporal characteristics between perfusion patterns, which allowed differentiation between pathological and nonpathological areas.  相似文献   
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