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Wei Zhang Nick Bansback Annelies Boonen Adam Young Amitabh Singh Aslam H Anis 《Arthritis research & therapy》2010,12(5):R177
Introduction
The Work Productivity and Activity Impairment (WPAI) questionnaire is a well validated instrument to measure impairments in work and activities. However, its validation among patients with rheumatoid arthritis (RA) has not been well established. The present study's purpose is to evaluate the construct validity of the WPAI-general health version among RA patients and its ability to differentiate between RA patients with varying health status. 相似文献3.
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In the context of ultrasound dynamic elastography imaging and characterization of venous thrombosis, we propose a method to induce mechanical resonance of confined soft heterogeneities embedded in homogenous media. Resonances are produced by the interaction of horizontally polarized shear (SH) waves with the mechanical heterogeneity. Due to such resonance phenomenon, which amplifies displacements up to 10 times compared to non-resonant condition, displacement images of the underlying structures are greatly contrasted allowing direct segmentation of the heterogeneity and a more precise measurement of displacements since the signal-to-noise ratio is enhanced. Coupled to an analytical model of wave scattering, the feasibility of shear wave induced resonance (SWIR) elastography to characterize the viscoelasticity of a mimicked venous thrombosis is demonstrated (with a maximum variability of 3% and 11% for elasticity and viscosity, respectively). More generally, the proposed method has the potential to characterize the viscoelastic properties of a variety of soft biological and industrial materials. 相似文献
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Wetlands are sensitive ecosystems that are increasingly subjected to threats from anthropogenic factors. In the last decades, coastal Mediterranean wetlands have been suffering considerable pressures from land use change, intensification of urban growth, increasing tourism infrastructure and intensification of agricultural practices. Remote sensing (RS) and Geographic Information Systems (GIS) techniques are efficient tools that can support monitoring Mediterranean coastal wetlands on large scales and over long periods of time. The study aims at developing a wetland indicator to support monitoring Mediterranean coastal wetlands using these techniques. The indicator makes use of multi-temporal Landsat images, land use reference layers, a 50m numerical model of the territory (NMT) and Corine Land Cover (CLC) for the identification and mapping of wetlands. The approach combines supervised image classification techniques making use of vegetation indices and decision tree analysis to identify the surface covered by wetlands at a given date. A validation process is put in place to compare outcomes with existing local wetland inventories to check the results reliability. The indicator´s results demonstrate an improvement in the level of precision of change detection methods achieved by traditional tools providing reliability up to 95% in main wetland areas. The results confirm that the use of RS techniques improves the precision of wetland detection compared to the use of CLC for wetland monitoring and stress the strong relation between the level of wetland detection and the nature of the wetland areas and the monitoring scale considered. 相似文献
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Anis Raddaoui Alexandra S. Sim?es Rekaya Baaboura Sofia Félix Wafa Achour Tarek Ben Othman Mohamed Béjaoui Raquel Sá-Le?o Assia Ben Hassen 《PloS one》2015,10(10)
BackgroundPneumococcal disease, a major cause of morbidity and mortality globally, has higher incidence among young children, the elderly and the immunocompromised of all ages. In Tunisia, pneumococcal conjugate vaccines (PCVs) are not included in the national immunization program. Also, few studies have described the epidemiology of S. pneumoniae in this country and, in particular, no molecular typing studies have been performed. The aim of this study was to evaluate serotype distribution, antimicrobial resistance and clonality of Streptococcus pneumoniae isolated from neutropenic patients in Tunisia.MethodsFifty-nine S. pneumoniae were isolated from infection (n = 31) and colonization (n = 28) sites of patients (children and adults) attending the National Centre of Bone Marrow Transplantation in Tunis between 2005–2011. All isolates were characterized by serotype, antimicrobial resistance pattern and multilocus sequence typing (MLST).ResultsThe majority (66.1%) of the isolates belonged to five serotypes all included in PCVs: 6B, 9V, 14, 19F and 23F. The potential coverage of the 10-valent and 13-valent PCV was of 71.2% and 76.3% respectively. Resistance rates were very high and 69.5% of the isolates were multidrug resistant: non-susceptibility rates to penicillin, amoxicillin and cefotaxime were 66.1%, 40.7% and 27.1%, respectively; resistance rates to erythromycin, clindamycin, tetracycline, chloramphenicol and trimethoprim-sulfamethoxazole, were 69.5%, 61.0%, 37.3%, 22.0% and 67.8%, respectively. The most frequent serotypes had STs characteristic of multidrug resistant international clones known to be highly successful and important causes of pneumococcal infection: Spain 23F-ST81, France 9V/14-ST156, Spain 6B-ST90, 19F-ST320, and Portugal 19F-ST177.ConclusionsThe majority of S. pneumoniae strains recovered from immunocompromised patients in Tunisia are representatives of multidrug resistant pandemic clones that express serotypes targeted by PCVs. To contain the burden of pneumococcal disease and improve treatment choices among Tunisian immunocompromised patients PCVs should be offered to all of them. 相似文献
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Mohamed Arbi Mejri Narimen Yousfi Khemais Zouaoui Mohamed Chiheb Ben Rayana Anis Chaouachi 《Biological Rhythm Research》2015,46(5):715-724
Sleep loss is among the most common yet frequently overlooked problems. This disruptive influence is associated with an adverse lipid profile (LP) and consequently results in an increased risk of cardiovascular disease. Furthermore, it has been well established that athletes are increasingly confronted with sleep problems. The aim of this study was to explore the effect of one night of partial sleep deprivation (PSD) on the cardiovascular profile and LP in young, trained athletes. Ten male Taekwondo athletes were randomized for three sleep conditions in a counterbalanced order: (i) following a baseline sleep night (BN), (ii) following PSD at the beginning of the night (PSDBN), and (iii) following PSD at the end of the night (PSDEN). Basal cardiovascular physiological measures were recorded, and blood samples were taken in the fasted state following each sleep session (i.e., in the morning at 07:00 h). The results showed that myoglobin and creatine phosphokinase increased significantly after PSDEN but not after PSDBN. By contrast, no alteration was observed in the LP and physiological parameters following the two types of PSD. In conclusion, these results show that PSDEN increases cardiac damage biomarkers significantly, even though they do not reach clinical significance. Thus, one night of PSD does not affect the physiological responses and biomarkers of LP in Taekwondo athletes. 相似文献
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Mekki Boussaha Diane Esquerré Johanna Barbieri Anis Djari Alain Pinton Rabia Letaief Gérald Salin Frédéric Escudié Alain Roulet Sébastien Fritz Franck Samson Cécile Grohs Maria Bernard Christophe Klopp Didier Boichard Dominique Rocha 《PloS one》2015,10(8)
High-throughput sequencing technologies have offered in recent years new opportunities to study genome variations. These studies have mostly focused on single nucleotide polymorphisms, small insertions or deletions and on copy number variants. Other structural variants, such as large insertions or deletions, tandem duplications, translocations, and inversions are less well-studied, despite that some have an important impact on phenotypes. In the present study, we performed a large-scale survey of structural variants in cattle. We report the identification of 6,426 putative structural variants in cattle extracted from whole-genome sequence data of 62 bulls representing the three major French dairy breeds. These genomic variants affect DNA segments greater than 50 base pairs and correspond to deletions, inversions and tandem duplications. Out of these, we identified a total of 547 deletions and 410 tandem duplications which could potentially code for CNVs. Experimental validation was carried out on 331 structural variants using a novel high-throughput genotyping method. Out of these, 255 structural variants (77%) generated good quality genotypes and 191 (75%) of them were validated. Gene content analyses in structural variant regions revealed 941 large deletions removing completely one or several genes, including 10 single-copy genes. In addition, some of the structural variants are located within quantitative trait loci for dairy traits. This study is a pan-genome assessment of genomic variations in cattle and may provide a new glimpse into the bovine genome architecture. Our results may also help to study the effects of structural variants on gene expression and consequently their effect on certain phenotypes of interest. 相似文献