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Background

Although several studies have shown that teaching EBM is effective in improving knowledge, at present, there is no convincing evidence that teaching EBM also changes professional behaviour in practice. Therefore, the primary aim of this study was to evaluate the effectiveness of a clinically integrated post-graduate training programme in EBM on evidence-based disability evaluation.

Methods and Findings

In a cluster randomised controlled trial, fifty-four case-based learning groups consisting of 132 physicians and 1680 patients were randomly assigned to the intervention or control groups. A clinically integrated, post-graduate, 5-day training programme in evidence-based medicine, consisting of (home) assignments, peer teaching, interactive training in searching databases, lectures and brainstorming sessions was provided to the intervention group. The control group received no training. The primary outcome was evidence-based disability evaluation, as indicated by the frequency in use of evidence of sufficient quality in disability evaluation reports. There are no general EBM behaviour outcome measures available. Therefore, we followed general guidelines for constructing performance indicators and defined an a priori cut-off for determination of sufficient quality as recommended for evaluating EB training. Physicians trained in EBM performed more evidence-based disability evaluations compared to physicians in the control group (difference in absolute proportion 9.7%, 95% CI 3.5 to 15.9). The primary outcome differences between groups remained significant after both cluster-adjusted analysis and additional sensitivity analyses accounting for subjects lost to follow-up.

Conclusions

A EBM programme successfully improved the use of evidence in a non-hospital based medical specialty. Our findings support the general recommendations to use multiple educational methods to change physician behaviour. In addition, it appeared important that the professional context of the intervention was very supportive in the sense that searches in databases, using and applying guidelines and other forms of evidence are considered standard practice and are encouraged by colleagues and management.  相似文献   
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Lycoteuthis lorigera is an oceanic squid that is abundant in the Benguela system. Little is known about the biology of this squid except that it is eaten in large numbers by numerous oceanic predators and that males grow to larger size than females, which is unique for oegopsid squid. The aim of this study was to better understand the biology of this species by investigating its age and growth, as well as its mating system. Toward this end, the age of 110 individuals, ranging from 35 to 110 mm, was estimated by counting statolith growth increments. Estimates of age ranged from 131 to 315 days and varied with mantle length. No significant differences were found in the size of males and females of equivalent ages. The relationship between ML and age for both sexes was best described by an exponential growth curve, probably because no early life stages were aged in this study. Only one mature male (ML 160 mm) was aged, and preliminary estimates suggest it was 386 days old. Instantaneous growth rates were low (0.54% ML/day and 1.4% BM/day) but consistent with enoploteuthid growth rates. When the growth rate of L. lorigera was corrected for temperature encountered during the animal’s life, the growth rate was fast (0.47% BM/degree-days) and consistent with the hypothesis that small cephalopods grow fast and that large cephalopods grow older, rather than fast. Mature females were often mated and had spermatangia in a seminal receptacle on the dorsal pouch behind the nuchal cartilage. Males probably transfer spermatangia to the females using their long second and/or third arm pair since the paired terminal organs open far from the mantle opening. M. A. C. Roeleveld deceased.  相似文献   
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Background  

Distance-based methods are popular for reconstructing evolutionary trees thanks to their speed and generality. A number of methods exist for estimating distances from sequence alignments, which often involves some sort of correction for multiple substitutions. The problem is to accurately estimate the number of true substitutions given an observed alignment. So far, the most accurate protein distance estimators have looked for the optimal matrix in a series of transition probability matrices, e.g. the Dayhoff series. The evolutionary distance between two aligned sequences is here estimated as the evolutionary distance of the optimal matrix. The optimal matrix can be found either by an iterative search for the Maximum Likelihood matrix, or by integration to find the Expected Distance. As a consequence, these methods are more complex to implement and computationally heavier than correction-based methods. Another problem is that the result may vary substantially depending on the evolutionary model used for the matrices. An ideal distance estimator should produce consistent and accurate distances independent of the evolutionary model used.  相似文献   
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Background  

Profile hidden Markov model (HMM) techniques are among the most powerful methods for protein homology detection. Yet, the critical features for successful modelling are not fully known. In the present work we approached this by using two of the most popular HMM packages: SAM and HMMER. The programs' abilities to build models and score sequences were compared on a SCOP/Pfam based test set. The comparison was done separately for local and global HMM scoring.  相似文献   
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Vampire squid (Vampyroteuthis infernalis) are considered phylogenetic relics with cephalopod features of both octopods and squids. They lack feeding tentacles, but in addition to their eight arms, they have two retractile filaments, the exact functions of which have puzzled scientists for years. We present the results of investigations on the feeding ecology and behaviour of Vampyroteuthis, which include extensive in situ, deep-sea video recordings from MBARI''s remotely operated vehicles (ROVs), laboratory feeding experiments, diet studies and morphological examinations of the retractile filaments, the arm suckers and cirri. Vampire squid were found to feed on detrital matter of various sizes, from small particles to larger marine aggregates. Ingested items included the remains of gelatinous zooplankton, discarded larvacean houses, crustacean remains, diatoms and faecal pellets. Both ROV observations and laboratory experiments led to the conclusion that vampire squid use their retractile filaments for the capture of food, supporting the hypothesis that the filaments are homologous to cephalopod arms. Vampyroteuthis'' feeding behaviour is unlike any other cephalopod, and reveals a unique adaptation that allows these animals to spend most of their life at depths where oxygen concentrations are very low, but where predators are few and typical cephalopod food is scarce.  相似文献   
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