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Carel Bron Michel Wensing Jo LM Franssen Rob AB Oostendorp 《BMC musculoskeletal disorders》2007,8(1):107
Background
Shoulder disorders are a common health problem in western societies. Several treatment protocols have been developed for the clinical management of persons with shoulder pain. However available evidence does not support any protocol as being superior over others. Systematic reviews provide some evidence that certain physical therapy interventions (i.e. supervised exercises and mobilisation) are effective in particular shoulder disorders (i.e. rotator cuff disorders, mixed shoulder disorders and adhesive capsulitis), but there is an ongoing need for high quality trials of physical therapy interventions. Usually, physical therapy consists of active exercises intended to strengthen the shoulder muscles as stabilizers of the glenohumeral joint or perform mobilisations to improve restricted mobility of the glenohumeral or adjacent joints (shoulder girdle). It is generally accepted that a-traumatic shoulder problems are the result of impingement of the subacromial structures, such as the bursa or rotator cuff tendons. Myofascial trigger points (MTrPs) in shoulder muscles may also lead to a complex of symptoms that are often seen in patients diagnosed with subacromial impingement or rotator cuff tendinopathy. Little is known about the treatment of MTrPs in patients with shoulder disorders. 相似文献4.
This paper presents the use of iterative dynamic programming employing exact penalty functions for minimum energy control problems. We show that exact continuously non-differentiable penalty functions are superior to continuously differentiable penalty functions in terms of satisfying final state constraints. We also demonstrate that the choice of an appropriate penalty function factor depends on the relative size of the time delay with respect to the final time and on the expected value of the energy consumption. A quadratic approximation (QA) of the delayed variables is much better than a linear approximation (LA) of the same for relatively large time delays. The QA improves the rate of convergence and avoids the formation of ‘kinks‘. A more general way of selecting appropriate penalty function factors is given and the results obtained using four illustrative examples of varying complexity corroborate the efficacy of the method. 相似文献
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Systematic reviews of the effectiveness of quality improvement strategies and programmes 总被引:4,自引:0,他引:4 下载免费PDF全文
J Grimshaw L McAuley L Bero R Grilli A Oxman C Ramsay L Vale M Zwarenstein 《Quality in health care》2003,12(4):298-303
Systematic reviews provide the best evidence on the effectiveness of healthcare interventions including quality improvement strategies. The methods of systematic review of individual patient randomised trials of healthcare interventions are well developed. We discuss methodological and practice issues that need to be considered when undertaking systematic reviews of quality improvement strategies including developing a review protocol, identifying and screening evidence sources, quality assessment and data abstraction, analytical methods, reporting systematic reviews, and appraising systematic reviews. This paper builds on our experiences within the Cochrane Effective Practice and Organisation of Care (EPOC) review group. 相似文献
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Physical activity and quality of life in older adults: Influence of health status and self-efficacy 总被引:2,自引:1,他引:1
Edward McAuley Ph.D. James F. Konopack Ed.M. Robert W. Motl Ph.D. Katherine S. Morris B.A. Shawna E. Doerksen M.S. Karl R. Rosengren Ph.D. 《Annals of behavioral medicine》2006,31(1):99-103
Background: Physical activity has been positively linked to quality of life (QOL) in older adults. Measures of health status and global
well-being represent common methods of assessing QOL outcomes, yet little has been done to determine the nature of the relationship
of these outcomes with physical activity.Purpose: We examined the roles played by physical activity, health status, and self-efficacy in global QOL (satisfaction with life)
in a sample of older Black and White women.Method: Participants (N = 249, M age = 68.12 years) completed multiple indicators of physical activity, self-efficacy, health status,
and QOL at baseline of a 24-month prospective trial. Structural equation modeling examined the fit of 3 models of the physical
activity and QOL relationship.Results: Analyses indicated that relationships between physical activity and QOL, self-efficacy and QOL were all indirect. Specifically,
physical activity influenced self-efficacy and QOL through physical and mental health status, which in turn influenced global
QOL.Conclusions: Our findings support a social cognitives model of physical activity’s relationship with QOL. Subsequent tests of hypothesized
relationships across time are recommended.
Funding for this study was provided by the National Institute on Aging (Grant AG 20118). We extend our sincere appreciation
to April Bell for all of her efforts on this project. 相似文献
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Andres A; Morales JM; Praga M; Campo C; Lahera V; Garcia-Robles R; Rodicio JL; Ruilope LM 《Nephrology, dialysis, transplantation》1997,12(7):1437-1440
BACKGROUND: Cyclosporin has been shown to facilitate renal vasoconstriction
and to have an antinatriuretic effect. The existence of an interference of
cyclosporin with the vasodilating properties of endothelium mediated by
nitric oxide production could mediate these effects. On the other hand, the
infusion of the nitric oxide precursor L-arginine has been shown to induce
renal vasodilatation and to facilitate natriuresis in normal volunteers. We
have investigated the renal effects of the administration of an infusion of
L-arginine in renal transplant patients chronically treated with
cyclosporin. To facilitate the analysis of the data the effects of the
administration of a similar dose of cyclosporin on renal function during
the infusion of a vehicle were also investigated during the administration
of a vehicle of L-arginine. DESIGN: Ten male renal transplant patients,
chronically treated with cyclosporin and with a stable renal function were
studied during 2 consecutive days after the administration of the usual
morning dose of cyclosporin. The first day they received an intravenous
infusion of vehicle and the second the infusion of graded doses of
L-arginine (50, 100, 150 mg/kg/h) during 3 consecutive h. RESULTS: The
first day, after cyclosporin administration a significant fall (P <
0.01) was observed in natriuresis and kaliuresis in the absence of changes
in renal plasma flow and glomerular filtration rate. After the
administration of L-arginine significant (P < 0.01) increases of renal
plasma flow, glomerular filtration rate, and natriuresis were seen. The
increase in blood levels of cyclosporin after its administration did not
differ between days 1 and 2. CONCLUSION: These results indicate that
L-arginine facilitates renal vasodilatation and natriuresis in renal
transplant patients. Furthermore, the observed increase in sodium excretion
could indicate that L-arginine counteracts the antinatriuretic effect of
cyclosporin.
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