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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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While gastrointestinal problems are common in ICU patients with multiple organ failure, gastrointestinal failure has not been given the consideration other organ systems receive. The aim of this study was to evaluate the incidence of gastrointestinal failure (GIF), to identify its risk factors, and to determine its association with ICU mortality.  相似文献   
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OBJECTIVE: The Baking Tray Task is a comprehensible, simple-to-perform test for use in assessing unilateral neglect. The aim of this study was to validate further its use with stroke patients. METHODS: The Baking Tray Task was compared with 2 versions of the Behaviour Inattention Test and a test for personal neglect. A total of 270 patients were subjected to a 3-item version of the Behaviour Inattention Test and 40 patients were subjected to an 8-item version of the Behaviour Inattention Test, besides the Baking Tray Task and the personal neglect test. RESULTS: The Baking Tray Task was more sensitive than the 3-item Behaviour Inattention Test, but the 8-item Behaviour Inattention Test was more sensitive than the Baking Tray Task. The best combination of any 3 tests was Baking Tray Task, Reading an article, and Figure copying; the 2 last-mentioned being a part of the 8-item Behaviour Inattention Test. CONCLUSION: Multi-item tests detect more cases of neglect than do single tests. However, it is tiresome for the patient to undergo a larger test battery than necessary. It is also time-consuming for the staff. Behavioural tests seem more appropriate when assessing neglect. The Baking Tray Task seems to be one of the most sensitive single tests, but its sensitivity can be further enhanced when it is used in combination with other tests.  相似文献   
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Trichoplusia ni immune genes up-regulated in response to bacterial infection have been isolated using differential display polymerase chain reaction. Here we report the cloning and characterisation of a gut-specific immune gene encoding an azurocidin-like protein. The deduced protein is 317 amino acid residues long with a hydrophobic C-terminus and a predicted 17-residue signal peptide. The mature T. ni protein shows 30% identity to human azurocidin, an antibacterial protein. Like azurocidin, the T. ni protein contains two amino acid substitutions in the active site triad normally present in serine proteases. The T. ni protein was synthesised with a six-histidine C-terminal extension using the baculovirus expression system. Sequencing of the recombinant azurocidin-like protein confirmed the predicted cleavage of the signal peptide. Northern blots show that T. ni azurocidin-like protein is expressed solely in the larval gut and that expression is up-regulated by injecting or feeding bacteria. Expression reaches its highest level at 10 h after bacteria injection.  相似文献   
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Real-time PCR was evaluated as a quantitative diagnostic method for Chlamydia pneumoniae infection using different respiratory samples. Real-time PCR had efficiency equal to or better than that of nested touchdown PCR. This study confirmed sputum as the best sampling material to detect an ongoing C. pneumoniae infection.  相似文献   
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