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Robert M Bennett Ronald Friend Kim D Jones Rachel Ward Bobby K Han Rebecca L Ross 《Arthritis research & therapy》2009,11(4):R120-14
Introduction
The Fibromyalgia Impact Questionnaire (FIQ) is a commonly used instrument in the evaluation of fibromyalgia (FM) patients. Over the last 18 years, since the publication of the original FIQ, several deficiencies have become apparent and the cumbersome scoring algorithm has been a barrier to widespread clinical use. The aim of this paper is to describe and validate a revised version of the FIQ: the FIQR. 相似文献4.
Tamar F Brionez Shervin Assassi John D Reveille Thomas J Learch Laura Diekman Michael M Ward John C Davis Jr Michael H Weisman Perry Nicassio 《Arthritis research & therapy》2009,11(6):R182-9
Introduction
Functional status is an integral component of health-related quality of life in patients with ankylosing spondylitis (AS). The purpose of this study was to investigate the role of psychological variables in self-reported functional limitation in patients with AS, while controlling for demographic and medical variables. 相似文献5.
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Regulation of directed motility in Myxococcus xanthus 总被引:6,自引:4,他引:2
Myxococcus xanthus is a Gram-negative bacterium that exhibits a complex life cycle. During vegetative growth, cells move as large swarms. However, when starved, cells aggregate into fruiting bodies and sporulate. Both vegetative swarming and developmental aggregation require gliding motility, which involves the slow movement of cells on a solid surface in the absence of flagella. The frequency of cell reversals controls the direction of movement and is regulated by the frz genes, which encode the 'frizzy' signal-transduction proteins. These proteins contain domains which bear striking similarities to the major chemotaxis proteins of the enteric bacteria: CheA, CheY, CheW, CheR, CheB and Tar. However, significant differences exist between the Myxococcus Frz proteins and the enteric Che/MCP proteins. For example, the Frz system contains three CheY-like response-regulator domains: one is present on FrzE, which also contains a CheA-like domain, and two are present on FrzZ, which is a novel protein required for attractant, but not for repellent, responses. The identification of multiple CheY homologues in this system indicates a more complex regulatory pathway than that found in the enteric bacteria. While responses to repellent stimuli appear to follow the enteric paradigm, responses to attractants during vegetative swarming and development are more complex and may involve self-generated autoattractants. The Frz signal-transduction system regulates directed motility in M. xanthus and is essential for controlling both fruiting-body development and vegetative swarming. 相似文献
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Joseph P Valentine 《Journal of experimental marine biology and ecology》2003,295(1):63-90
Despite recent rapid increases in the occurrence of nonindigenous marine organisms in the marine environment, few studies have critically examined the invasion process for a marine species. Here we use manipulative experiments to examine processes of invasion for the Asian kelp Undaria pinnatifida (Harvey) Suringar at two sites on the east coast of Tasmania. Disturbance to reduce cover of the native algal canopy was found to be critical in the establishment of U. pinnatifida, while the presence of a stable native algal canopy inhibited invasion. In the first sporophyte growth season following disturbance of the canopy, U. pinnatifida recruited in high densities (up to 19 plants m−2) while remaining rare or absent in un-manipulated plots. The timing of disturbance was also important. U. pinnatifida recruited in higher densities in plots where the native canopy was removed immediately prior to the sporophyte growth season (winter 2000), compared with plots where the canopy was removed 6 months earlier during the period of spore release (spring 1999). Removal of the native canopy also resulted in a significant increase in cover of sediment on the substratum. In the second year following canopy removal, U. pinnatifida abundance declined significantly, associated with a substantial recovery of native canopy-forming species. A feature of the recovery of the native algal canopy was a significant shift in species composition. Species dominant prior to canopy removal showed little if any signs of recovery. The recovery was instead dominated by canopy-forming species that were either rare or absent in the study areas prior to manipulation of the canopy. 相似文献
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