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The objective of this study was to analyze whether a meta‐analysis could allow us to draw useful conclusions about the risk factors for falls in the elderly. A systematic review was carried out of various databases and completed manually. To satisfy the inclusion criteria, an article had to examine a population of subjects aged over 60 years to pertain to falls occurring during daily living activities, and to involve observational or interventional studies. This review identified 4405 indexed articles published between 1981 and 2011. Of the 220 studies with available data that were included in the final study, just 4% were interventional. Among these 220 studies, just 45% offered a satisfactory level of scientific proof. In total, 88 meta‐analyses were carried out on the 156 potential protectors or risk factors that were identified. Our systematic review and meta‐analyses ensured that high‐quality results were obtained from this comprehensive literature search and included a detailed assessment of the quality of the included studies. Several factors appeared to be disproportionately represented in the literature, a fact that likely reflects the objective and precise assessment of these factors rather than their importance in the falls of the elderly. Thus, we cannot be certain that we obtained the most comprehensive analysis of the risk factors for falling with this method. Meta‐analyses can help to define the association between falls and various risk factors, but they have to be used complementary to systematic review for the assessment of risk factors. Geriatr Gerontol Int 2013; 13: 250–263.  相似文献   
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Correct sex assessment of skeletonized human remains allows investigators to undertake a more focused search of missing persons' files to establish identity. Univariate and multivariate odontometric sex assessment has been explored in recent years on small sample sizes and have not used a test sample. Consequently, inconsistent results have been produced in terms of accuracy of sex allocation. This paper has derived data from a large sample of males and females, and applied logistic regression formulae on a test sample. Using a digital caliper, buccolingual and mesiodistal dimensions of all permanent teeth (except third molars) were measured on 600 dental casts (306 females, 294 males) of young adults (18–32 years), and the data subjected to univariate (independent samples' t-test) and multivariate statistics (stepwise logistic regression analysis, or LRA). The analyses revealed that canines were the most sexually dimorphic teeth followed by molars. All tooth variables were larger in males, with 51/56 (91.1%) being statistically larger (p < 0.05). When the stepwise LRA formulae were applied to a test sample of 69 subjects (40 females, 29 males) of the same age range, allocation accuracy of 68.1% for the maxillary teeth, 73.9% for the mandibular teeth, and 71% for teeth of both jaws combined, were obtained. The high univariate sexual dimorphism observed herein contrasts with some reports of low, and sometimes reverse, sexual dimorphism (the phenomenon of female tooth dimensions being larger than males'); the LRA results, too, are in contradiction to a previous report of virtually 100% sex allocation for a small heterogeneous sample. These reflect the importance of using a large sample to quantify sexual dimorphism in tooth dimensions and the application of the derived formulae on a test dataset to ascertain accuracy which, at best, is moderate in nature.  相似文献   
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To assess the association between the elevation of plasma homocysteine (Hcy) level and long‐term levodopa (L‐dopa) therapy in idiopathic Parkinson's disease (PD). We performed a systematic literature review to recruit original studies published up to May 14, 2012. Studies enrolled should be controlled, with specific information of long‐term L‐dopa application and plasma Hcy in patients with PD. Effects were summarized using standardized mean differences (SMDs) or weighted mean differences (WMDs). Our search enrolled 22 eligible studies. Plasma Hcy levels were significantly higher in L‐dopa‐treated patients than those in healthy controls [SMD 0.97; 95% confidence interval (CI) 0.80–1.14, < 0.001], L‐dopa‐naïve patients with PD (SMD 0.99; 95% CI 0.54–1.44, < 0.001), and untreated patients (SMD 0.52; 95% CI 0.18–0.86, < 0.01). However, its levels in untreated patients with PD were not significantly higher than in healthy controls (SMD 0.24; 95% CI ?0.03 to 0.51, > 0.05). Patients with PD treated with L‐dopa plus catechol‐O‐methyltransferase inhibitor (COMT‐I) showed lower plasma Hcy concentrations compared with L‐dopa‐treated patients (WMD 4.62; 95% CI 2.89–6.35, < 0.001). L‐dopa treatment is associated with the increase in plasma Hcy level in patients with PD. COMT‐I may attenuate L‐dopa‐induced elevation of Hcy level.  相似文献   
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ABSTRACT

Functional recovery following general nerve reconstruction is often associated with poor results. Comparing to rat and mice experimental studies, there are much fewer investigations on nerve regeneration and repair in the sheep, and there are no studies on this subject using gait analysis in the sheep model as an assessment tool. Additionally, this is the first study evaluating obstacle negotiation and the compensatory strategies that take place at each joint in response to the obstacle during locomotion in the sheep model. This study aims to get kinematic data to serve as a template for an objective assessment of the ankle joint motion in future studies of common peroneal nerve (CP) injury and repair in the ovine model. Our results show that a moderately high obstacle set to 10% of the sheep’s hindlimb length was associated to several spatial and temporal strategies in order to increase hoof height during obstacle negotiating. Sheep efficiently cleared an obstacle by increasing knee, ankle and metatarsophalangeal flexion during swing, whereas the hip joint is not affected. This study establishes the bounds of normal motion in the neurologically intact hindlimb when approached and cleared an obstacle and provides baseline data for further studies of peripheral nerve research in the ovine model.  相似文献   
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