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Chronic food restriction has been shown to enhance glucose metabolism in adipocytes from lean Zucker rats at 10, 26, and 52 weeks of age compared to ad libitum-fed lean rats. Only adipocytes from food restricted 10-week-old obese rats demonstrated this response. In this study, lean and obese rats were food restricted from 5 until 14 weeks of age to determine the age at which adipocytes from obese rats were no longer affected by this intervention. Effects of 1 week of refeeding were also determined. When the rats were killed, body weights were highest in control rats followed by restricted/refed and then restricted rats within each genotype. Epididymal pad weights of lean rats were resistant to dietary intervention, while those of obese-restricted and obese-restricted/refed rats weighed less than pads of obese-control rats. Retroperitoneal pad weight was lowered by food restriction in both genotypes; but only that of lean-restricted/refed rats totally recovered with refeeding. Adipocytes of lean-restricted rats had the highest conversion of glucose to CO2. Glyceride-glycerol production was higher in obese compared to lean rats, but restricted rats had elevated conversion of glucose to fatty acids. In general, these results indicate that by 14 weeks of age obese Zucker rats no longer respond to food restriction with an elevated rate of glucose metabolism in adipocytes. 相似文献
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Brian F O'Donnell Marcia A Wilt Ann Marie Hake Julie C Stout Sandra C Kirkwood Tatiana Foroud 《Movement disorders》2003,18(9):1027-1034
Disturbances of visual cognition, visuomotor performance, and visual memory have been described frequently in Huntington's disease (HD). Early stage visual abnormalities could contribute to these deficits. We evaluated visual processing in 20 control subjects who were non-gene carriers at risk for HD, nine presymptomatic gene-positive subjects, and eight subjects with a recent diagnosis of Huntington's disease. Visual perceptual tests of contrast sensitivity and motion discrimination were used to probe early stage visual processing. Extraocular movements were evaluated in a neurologic examination, and the Digit Symbol test was used to test visual motor performance. Contrast sensitivity did not differ among the three groups. Motion discrimination was impaired in HD subjects but not in the presymptomatic gene carriers when compared to gene noncarriers. Among gene carriers, impaired motion discrimination performance was associated with poorer Digit Symbol performance and extraocular abnormalities. These findings suggest that the early stages of HD are associated with disturbances of motion perception as well as disruptions of visual motor and ocular motor performance. 相似文献
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High-protein Weight-loss Diets: Are They Safe and Do They Work? A Review of the Experimental and Epidemiologic Data 总被引:6,自引:0,他引:6
Julie Eisenstein M.D. Susan B. Roberts Ph.D. Gerard Dallal Ph.D. Edward Saltzman M.D. 《Nutrition reviews》2002,60(7):189-200
Recommendations for increased consumption of protein are among the most common approaches of popular or fad diets. This review summarizes the effects of dietary protein on satiety, energy intake, thermogenesis, and weight loss, as well as its effect on a variety of health outcomes in adults. In short-term studies, dietary protein modulates energy intake via the sensation of satiety and increases total energy expenditure by increasing the thermic effect of feeding. Whereas these effects did not contribute to weight and fat loss in those studies in which energy intake was fixed, one ad libitum study does suggest that a high-protein diet results in a greater decrease in energy intake, and therefore greater weight and fat loss. In terms of safety, there is little long-term information on the health effects of high-protein diets. From the available data, however, it is evident that the consumption of protein greater than two to three times the U.S. Recommended Daily Allowance contributes to urinary calcium loss and may, in the long term, predispose to bone loss. Caution with these diets is recommended in those individuals who may be predisposed to nephrolithiasis or kidney disease, and particularly in those with diabetes mellitus. 相似文献
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Mark Foord BA MA Julie Savory BA MA MCiH Dianne Sodhi BA MA MCiH 《Health & social care in the community》2004,12(2):126-133
This paper reflects on a research project funded by a consortium of leading sheltered housing (SH) providers and their regulatory body, the Housing Corporation. The project aimed to ascertain which aspects of SH older people perceived to be central to their satisfaction and the methods they judged most appropriate to measuring this. We outline key policy developments of importance to SH (specifically the development of performance measurement regimes), and changes in the nature of SH, which are driving providers to re‐evaluate how they measure user satisfaction. We discuss the aims of the project, our methodology and findings, and conclude by raising critical questions about the process of measuring satisfaction within an increasingly managerialised housing system. We argue that this favours standardised methods of information gathering (such as questionnaires) rather than engage with clients in order to develop methods and systems capable of eliciting qualitative issues of concern to them. Our conclusions are, we believe, applicable to health and social care provision, where similar tensions exist around performance measurement and user satisfaction. 相似文献
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Beta-adrenergic blockers reduce the risk of fracture partly by increasing bone mineral density: Geelong Osteoporosis Study. 总被引:7,自引:0,他引:7
Julie A Pasco Margaret J Henry Kerrie M Sanders Mark A Kotowicz Ego Seeman Geoffrey C Nicholson 《Journal of bone and mineral research》2004,19(1):19-24
This population-based study documented beta-blocker use in 59/569 cases with incident fracture and 112/775 controls. OR for fracture associated with beta-blocker use was 0.68 (95%CI, 0.49-0.96). Beta-blockers were associated with higher BMD at the total hip (2.5%) and UD forearm (3.6%) after adjusting for age, anthropometry, and thiazide use. Beta-blocker use is associated with reduced fracture risk and higher BMD. INTRODUCTION: Animal data suggests that bone formation is under beta-adrenergic control and that beta-blockers stimulate bone formation and/or inhibit bone resorption. MATERIALS AND METHODS: We evaluated the association between beta-blocker use, bone mineral density (BMD), and fracture risk in a population-based study in Geelong, a southeastern Australian city with a single teaching hospital and two radiological centers providing complete fracture ascertainment for the region. Beta-blocker use was documented for 569 women with radiologically confirmed incident fractures and 775 controls without incident fracture. Medication use and lifestyle factors were documented by questionnaire. RESULTS: Odds ratio for fracture associated with beta-blocker use was 0.68 (95% CI, 0.49-0.96) for any fracture. Adjusting for age, weight, medications, and lifestyle factors had little effect on the odds ratio. Beta-blocker use was associated with a higher BMD at the total hip (2.5%, p = 0.03) and ultradistal forearm (3.6%, p = 0.04) after adjustment for age, anthropometry, and thiazide use. CONCLUSION: Beta-blockers are associated with a reduction in fracture risk and higher BMD. 相似文献
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Kathleen Matuska Amy Giles-Heinz Nancy Flinn Michael Neighbor Julie Bass-Haugen 《The American journal of occupational therapy》2003,57(2):220-224
OBJECTIVE: The purpose of this study was to evaluate a pilot occupational therapy wellness program designed to teach elders the importance of participation in meaningful social and community occupations to their quality of life. METHOD: Sixty-five older adults participated in this pilot wellness program held at each of three senior apartment complexes. Measures of health-related quality of life using the SF-36 Health Survey and frequencies of social and community participation from a program-specific intake form were completed by 39 participants before and after the 6-month program. Participants also evaluated components of the program through a satisfaction survey. RESULTS: Scores on the SF-36 Health Survey were significantly higher in vitality, social functioning, and the mental health summary scores following participation in the program. Participants reported an increased frequency of socialization and community participation with an average of 55% participating in at least three or more activities per week before the program to an average of 66% participating after the program. Participants who benefited the most attended more classes, were older, and were nondrivers. Eighty percent of those polled rated the pilot program as good or excellent. CONCLUSION: This pilot study provides additional support for prevention efforts for elders in the community. Wellness programs for seniors may be most effective if targeted to those who are older and nondrivers. 相似文献
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