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目的 通过对已报道的全膝关节置换翻修术文献进行总结分析,讨探膝关节置换翻修术前后的膝关节功能、翻修的主要原因、主要并发症及不同假体的术后疗效.方法 按照以下标准收集和分析有关全膝关节置换翻修术的文献:①1990年至2002年间发表,②报告患者数大于10例,③采用通用的膝关节评分标准.一名骨科专科医生独立收集数据,一名医学统计学专家独立采用Meta统计方法分析数据.结果 共有33 篇符合条件的文献被收集.患者共1356 例,其中男429例,女611例(部分文献性别分类数据缺失),平均年龄67岁(45~49岁),加权平均随访时间57个月( 6~108 个月),加权平均术前膝关节功能总评分为49 分(15~94分),术后为84分( 58~109分),全膝关节置换翻修术前后的总评分、功能评分、活动范围等有显著性提高,差异有统计学意义(总评分t=12.507,P<0.01, 功能评分t=4.704,P<0.01,活动范围:t=5.346,P< 0.01).全膝关节置换翻修术的原因主要是假体松动(55%),其它包括聚乙烯磨损(11%)、假体不稳(10%)、感染(7%).翻修术后的主要并发症仍然为假体松动(18%),其它包括假体不稳(16% )、感染(16% )、髌骨问题( 15% )及不明原因的膝关节疼痛(13%).髌骨问题包括髌骨脱位、半脱位、髌韧带撕裂、髌股关节疼痛等.结论 可以认为膝关节置换后翻修术是一种安全有效的手术.假体松动是膝关节置换翻新的主要原因和并发症.  相似文献   
3.
We report preliminary findings on EEG oscillatory correlates of working memory in mild cognitive impairment (MCI) and Alzheimer's disease (AD). Event-related desynchronization (ERD) and synchronization (ERS) of the 1-20 Hz EEG frequencies were studied using wavelet transforms in elderly controls, MCI patients and mild probable AD patients performing an auditory-verbal Sternberg memory task. Behaviourally, the AD patients made more errors than the controls and the MCI group. Statistically significant differences during the encoding of the memory set were found between the controls and the MCI group, such that the latter group showed ERD in the approximately 10-20 Hz frequencies. The findings may reflect different, compensatory encoding strategies in MCI. During retrieval, the most obvious differences were observed between the controls and the AD group: the ERD in the approximately 7-17 Hz frequencies was absent in the AD group particularly in anterior and left temporal electrode locations. This finding might indicate that AD is associated with deficient lexical-semantic processing during the retrieval phase in working memory tasks. Future studies with larger patient groups are needed to establish the diagnostic value of ERD/ERS patterns in MCI and AD.  相似文献   
4.
Mixed microbial aetiology of community-acquired pneumonia in children   总被引:2,自引:0,他引:2  
Seven paediatric studies on community-acquired pneumonia with serological methods for both viruses and bacteria have been published, allowing the evaluation of concomitant multiple etiological findings. In these studies, dual viral infection has been present in 0-14%, dual bacterial infection likewise in 0-14%, and mixed viral-bacterial infection in 3-30% of the pneumonia cases. The results confirm former clinical observations that respiratory viruses often pave the way for airway-colonising bacteria. The measured frequency of multiple infections has been dependent on the available test panel, mainly on the tests used for pneumococcal aetiology. Mixed viral-bacterial infections have been especially common in young children under 2 years of age, reflecting the high frequency of respiratory syncytial virus infections and their tendency to induce bacterial co-infections. No microbe-specific viral-bacterial associations have been demonstrated. The clinical implications of mixed viral-bacterial infections, compared with viral infections alone or bacterial infections alone, have so far remained unresolved. Current guidelines recommend antibiotic therapy for all community-acquired pneumonia cases in children.  相似文献   
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Neuropathological diagnostic criteria for Creutzfeldt-Jakob disease (CJD) and other human transmissible spongiform encephalopathies (prion diseases) are proposed for the following disease entities: CJD - sporadic, iatrogenic (recognised risk) or familial (same disease in 1st degree relative): spongiform encephalopathy in cerebral and/or cerebellar cortex and/or subcortical grey matter; or encephalopathy with prion protein (PrP) immuno-reactivity (plaque and/or diffuse synaptic and/or patchy/perivacuolar types). Gerstmann-Sträussler-Scheinker disease (GSS) (in family with dominantly inherited progressive ataxia and/or dementia): encephalo(myelo)pathy with multicentric PrP plaques. Familial fatal insomnia (FFI) (in member of a family with PRNP178 mutation): thalamic degeneration, variable spongiform change in cerebrum. Kuru (in the Fore population). Without PrP data, the crucial feature is the spongiform change accompanied by neuronal loss and gliosis. This spongiform change is characterised by diffuse or focally clustered small round or oval vacuoles in the neuropil of the deep cortical layers, cerebellar cortex or subcortical grey matter, which might become confluent. Spongiform change should not be confused with non-specific spon-giosis. This includes status spongiosus (“spongiform state”), comprising irregular cavities in gliotic neuropil following extensive neuronal loss (including also lesions of “burnt-out” CJD), “spongy” changes in brain oedema and metabolic encephalopathies, and artefacts such as superficial cortical, perineuronal, or perivascular vacuolation; focal changes indistinguishable from spongiform change may occur in some cases of Alzheimer's and diffuse Lewy body diseases. Very rare cases might not be diagnosed by these criteria. Then confirmation must be sought by additional techniques such as PrP immunoblotting, preparations for electron microscopic examination of scrapie associated fibrils (SAF), molecular biologic studies, or experimental transmission.  相似文献   
7.
PurposeCompletely displaced distal radius fractures in children have been traditionally reduced and immobilized with a cast or pin fixed. Cast immobilization leaving the fracture displaced in the bayonet position has been recently suggested as a non-invasive and effective treatment alternative. This is a pilot comparative study between reduction and no reduction.MethodsWe assessed subjective, functional and radiographic outcome after a minimum 2.5-year follow-up in 12 children under ten years of age who had sustained a completely displaced metaphyseal radius fracture, which had been immobilized leaving the fracture in an overriding position (shortening 3 mm to 9 mm). A total of 12 age-matched patients, whose similar fractures were reduced and pin fixed, were chosen for controls. ResultsAt follow-up none of the 24 patients had visible forearm deformity and the maximal angulation in radiographs was 5° Forearm and wrist movement was restored (< 10° of discrepancy) in all 24 patients. Grip strength ratio was normal in all but three surgically treated patients. All patients had returned to their previous activities. One operatively treated boy who was re-operated on reported of pain (visual analogue scale 2).ConclusionThe results of this study do not demonstrate the superiority of reduction and pin fixation over cast immobilization in the bayonet position of closed overriding distal metaphyseal radius fractures in children under ten years with normal neurovascular findings.Level of evidenceIII  相似文献   
8.
Type IV collagenases in invasive tumors   总被引:11,自引:0,他引:11  
Summary The matrix metalloproteinases appear to be elevated in tumors with metastatic potential, and may well be involved in penetration of the basement membrane and degradation of extracellular proteins including type IV collagen. An imbalance between the 72 kDa and 92 kDa type IV collagenases and the associated tissue inhibitors of these metalloproteinases (TIMPs) may therefore have a role in the invasive phenotype. Cultured tumor cells with invasive potential secrete both type IV collagenases, though in tumors there is some evidence that the 72 kDa form at least may be produced by stromal cells at the invading tumor front rather than primarily by the tumor cells themselves, while the 92 kDa form may be synthesized in macrophages near the front. These collagenases are elevated in invasive as compared within situ tumor components, but their specific roles and prognostic significance are not yet established.  相似文献   
9.
The cosmetic results of the breast (144 patients)were analysed after segmental resection and axillary dissectionwith or without postoperative radiotherapy for early low-riskbreast cancers. Cosmetic results were assessed over time(3, 9, 18, 36, 48 months respectively) bythe patient and by the physician. Patients ratedthe overall cosmetic result good or excellent in92% of cases after 3 months. The proportionof good or excellent cosmetic results decreased overtime and after four years 89% of patientsclassified themselves in this category, whereas the physicianassessed the outcome as good or excellent in91% of cases after 3 months and 75%after 4 years. The inter-observer consistency between physicianand patient in assessing the cosmetic outcome was=0.42 at the beginning and decreasedover time (=0.07 after 4 years).The intra-observer variation over time was =0.53 for the patient and =0.32for the physician.Inter-observer consistency between patient and physician was moderateimmediately following treatment but decreased over time. Thefeeling of satisfaction of the patient was relativelystable whereas the opinion of the physician becamesomewhat more critical over time. Therefore the intra-observerconsistency over time was somewhat better for thepatient than for the physician.  相似文献   
10.
 In order to evaluate the effect of the introduction of recent similar guidelines on the treatment of acute urinary tract infection (UTI) in children, and possible changes in its epidemiology, we analyzed the records of hospital discharge for acute UTI under the age of 15 years in England and Wales between 1979 and 1993 and in Finland between 1978 and 1994. Cases were defined by the ICD9 diagnostic codes 590.1 (acute pyelonephritis) and 599.0 (UTI, site not specified) for males and females according to three age groups (0–4, 5–9, and 10–14 years). We also compared the registry data on kidney transplants due to end-stage renal disease caused by recurrent pyelonephritis in the United Kingdom and Finland. In England the rate of attack of symptomatic UTI per 1,000 girls under 15 years increased from 0.74 (95% confidence interval 0.71–0.76) in 1987 to 1.32 (1.29–1.35) in 1993 (P<0.001, test for trend). The respective figures for Finnish girls were 1.74 (1.62–1.86) in 1987 and 1.62 (1.51–1.74) in 1993 (P=0.72). In English boys, the increase in the attack rate was from 0.38 (0.36–0.40) in 1987 to 0.70 (0.68–0.73) in 1993 (P<0.001). In Finnish boys the respective figures were 0.74 (0.66–0.82) in 1987 and 0.88 (0.80–0.97) in 1993 (P<0.02). The observed increases in the attack rates of UTI most probably relate to increased referral of acute UTI patients to hospitals for the recommended imaging studies rather than changing occurrence. Publication of guidelines for treatment of UTI in children, consolidating more-general awareness, may have contributed to this. The mean annual numbers of kidney transplants in the United Kingdom and Finland during 1989–1995 due to end-stage renal disease caused by pyelonephritis were of similar magnitude, i.e., 1.9 (1.6–2.3) transplants per million inhabitants in the United Kingdom and 2.8 (1.5–4.7) transplants per million inhabitants in Finland. The decreasing trend in these figures in both countries, although statistically significant only in the United Kingdom (P<0.05, test for trend), suggests improved long-term outcome of these patients induced by better diagnosis and treatment of pyelonephritis and the diseases related to it, such as congenital malformations. According to our data, valid clinical guidelines are effective in changing clinical practice. Received: 1 September 1997 / Revised: 29 April 1998 / Accepted: 29 April 1998  相似文献   
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