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ABSTRACT: BACKGROUND: Accumulation of lifestyle physical activity is a current aim of health promotion, with increased stair climbing one public health target. While the workplace provides an opportunity for regular stair climbing, evidence for effectiveness of point-of-choice interventions is equivocal. This paper reports a new approach to worksite interventions, aimed at changing attitudes and, hence, behaviour. METHODS: Pre-testing of calorific expenditure messages used structured interviews with members of the public (n = 300). Effects of multi-component campaigns on stair climbing were tested with quasi-experimental, interrupted time-series designs. In one worksite, a main campaign poster outlining the amount of calorific expenditure obtainable from stair climbing and a conventional point-of-choice prompt were used (Poster alone site). In a second worksite, additional messages in the stairwell about calorific expenditure reinforced the main campaign (Poster + Stairwell messages site). The outcome variables were automated observations of stair and lift ascent (28,854) and descent (29,352) at baseline and for three weeks after the intervention was installed. Post-intervention questionnaires for employees at the worksites assessed responses to the campaign (n = 253). Analyses employed Analysis of variance with follow-up Bonferroni t-tests (message pre-testing), logistic regression of stair ascent and descent (campaign testing), and Bonferroni t-tests and multiple regression (follow-up questionnaire). RESULTS: Pre-testing of messages based on calorific expenditure suggested they could motivate stair climbing if believed. The new campaign increased stair climbing, with greater effects at the Poster + Stairwell messages site (OR = 1.52, 95 % CI = 1.40-1.66) than Posters alone (OR = 1.24, 95 % CI = 1.15-1.34). Follow-up revealed higher agreement with two statements about calorific outcomes of stair climbing in the site where they were installed in the stairwell, suggesting more positive attitudes resulted from the intervention. Future intentions for stair use were predicted by motivation by the campaign and beliefs that stair climbing would help weight control. CONCLUSIONS: Multi-component campaigns that target attitudes and intentions may substantially increase stair climbing at work. 相似文献
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J. F. I. Anderson L. V. Augoustakis R. J. Holmes B. R. Chambers 《Internal medicine journal》2010,40(1):61-65
Locked-in syndrome (LIS) is commonly associated with a poor prognosis, particularly if the aetiology is stroke. Dealing with individuals with LIS and a poor prognosis raises the issue of introducing end-of-life discussions with the patient and/or family in the acute period of the illness. Existing literature regarding LIS provides little guidance about end-of-life decision-making in the acute management phase. We aim to provide some guidance for clinicians holding end-of-life discussions in the acute management period. We report two cases of relatively young individuals with LIS secondary to brainstem stroke. Both cases had a very poor prognosis and end-of-life discussions were commenced by the treating team in the acute phase. Despite the severity of their conditions, in neither case were end-of-life discussions well tolerated by the family in the weeks following admission. We suggest that LIS patients and their families, who have chosen to persist with full medical management after diagnosis of LIS, should be provided with sufficient time to adjust to the catastrophic changes that have occurred before further end-of-life discussions are pursued. Education and support are likely to be highly beneficial in the acute period post stroke as they allow the patient and family to develop a realistic understanding of the likely outcomes of their decisions. 相似文献
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Chambers LW Hendriks A Hall HL Raina P McDowell I;Care for the Caregiver Working Group 《Chronic diseases in Canada》2004,25(3-4):108-118
In December 2002, a national workshop was held in Ottawa to guide research directions for the caregiving of people with Alzheimer's disease in Canada. Prior to the workshop, a search was conducted to identify Canadian-based investigators who have conducted research related to caregiving of individuals with cognitive impairment, Alzheimer's disease and other dementia, identify relevant Canadian research studies, and provide an overview of results and themes emerging from this research. This paper summarizes findings from our search for Canadian studies, research themes identified at the national workshop in Ottawa, and recommendations from the workshop. The report first outlines patterns of caregiving and subsequently focusses on the impact of different ways of assisting Alzheimer's caregivers. It concludes by outlining the methodological challenges of observational and intervention studies related to Alzheimer's caregiving and recommendations on how to increase Canada's capacity to conduct research on Alzheimer's caregiving. 相似文献
98.
Hydrogen peroxide is essential for estrogen-deficiency bone loss and osteoclast formation 总被引:7,自引:0,他引:7
We recently found that estrogen deficiency leads to a lowering of thiol antioxidant defenses in rodent bone. Moreover, administration of agents that increase the concentration in bone of glutathione, the main intracellular antioxidant, prevented estrogen-deficiency bone loss, whereas depletion of glutathione by buthionine sulfoximine administration provoked substantial bone loss. To analyze further the mechanism by which antioxidant defenses modulate bone loss, we have now compared expression of the known antioxidant enzymes in osteoclasts. We found that glutathione peroxidase 1 (Gpx), the enzyme primarily responsible for the intracellular degradation of hydrogen peroxide, is overwhelmingly the predominant antioxidant enzyme expressed by osteoclasts and that its expression was increased in bone marrow macrophages by receptor activator of nuclear factor-kappaB ligand (RANKL) and in osteoclasts by 17beta-estradiol. We therefore tested the effect of overexpression of Gpx in osteoclasts by stable transfection of RAW 264.7 (RAW) cells, which are capable of osteoclastic differentiation in response to RANKL, with a Gpx-expression construct. Osteoclast formation was abolished. The Gpx expression construct also suppressed RANKL-induced nuclear factor-kappaB activation and increased resistance to oxidation of dihydrodichlorofluorescein by exogenous hydrogen peroxide. We therefore tested the role of hydrogen peroxide in the loss of bone caused by estrogen deficiency by administering pegylated catalase to mice. We found that catalase prevented ovariectomy-induced bone loss. These results suggest that hydrogen peroxide is the reactive oxygen species responsible for signaling the bone loss of estrogen deficiency. 相似文献
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Limited red blood cell (RBC) regeneration often prevents collection of sufficient blood from autologous donors. We studied the effects of subcutaneous recombinant erythropoietin (rEPO) in subjects making frequent blood donations. Six healthy iron-replete male subjects took rEPO (200 U/kg) subcutaneously daily, and donated blood (450 mL) twice a week for 3 weeks. During a control study, these subjects also attempted twice-weekly blood donations without rEPO. Four other males given rEPO, including one with idiopathic hemochromatosis, waited until day 8 to begin blood donations. All healthy subjects took oral ferrous sulfate. Subcutaneous rEPO given with blood donations resulted in a marked reticulocytosis (mean peak value 568 +/- 159 x 10(9)/L v 235 +/- 77 x 10(9)/L, control study; P < .05), and enhanced RBC production at 28 days (1,208 +/- 227 mL v 719 +/- 161 mL, P < .05). rEPO in advance of blood donations was slightly less effective in normal subjects (941 +/- 139 mL, P < .05); however, the subject with hemochromatosis produced substantially more RBCs (1,764 mL) than any normal subject. rEPO-treated normal subjects (but not the rEPO-treated patient with hemochromatosis or untreated controls) produced iron-deficient RBCs with elevated zinc protoporphyrin levels and low hemoglobin content. These cells appeared within 1 week of rEPO administration and before laboratory confirmation of depleted iron stores. Thus, subcutaneous rEPO is an effective stimulant of erythropoiesis in nonanemic blood donors. However, in addition to eventual depletion of iron stores, early functional iron deficiency affects response to the drug. 相似文献