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61.
WILLIAM J EVANS PhD DEANNA CYR-CAMPBELL MS RD 《Journal of the American Dietetic Association》1997,97(6):632-638
Advancing age is associated with a remarkable number of changes in body composition, including reduction in lean body mass and increase in body fat, which have been well documented. Decreased lean body mass occurs primarily as a result of losses in skeletal muscle mass. This age-related loss in muscle mass has been termed “sarcopenia”. Loss in muscle mass accounts for the age-associated decreases in basal metabolic rate, muscle strength, and activity levels, which, in turn are the cause of the decreased energy requirements of the elderly. In sedentary persons, the main determinant of energy expenditure is fat-free mass, which declines by about 15% between the third and eighth decade of life. It also appears that declining energy needs are not matched by an appropriate decline in energy intake, with the ultimate result being increased body fat content. Increased body fatness and increased abdominal obesity are thought to be directly linked to the greatly increased incidence of non-insulin-dependent diabetes mellitus among the elderly. In this review we will discuss the extent to which regularly performed exercise can affect nutrition needs and functional capacity in the elderly. We will also discuss a variety of concerns when prescribing exercise in the elderly, such as planning for a wide variability in functional status, medical status, and training intensity and duration. Finally, we will attempt to provide some basic guidelines for beginning an exercise program for older men and women and establishing community-based programs. 相似文献
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LISA HARNACK DrPH RD GLADYS BLOCK PHD AMY SUBAR PhD RD SYLVIA LANE PhD RICHARD BRAND PhD 《Journal of the American Dietetic Association》1997,97(9):957-965
Objective To examine the relationship of cancer prevention-related nutrition knowledge, beliefs, and attitudes to cancer prevention dietary behavior.Subjects/setting Noninstitutionalized US adults aged 18 years and older.Methods Data collected in the 1992 National Health Interview Survey Cancer Epidemiology Supplement were analyzed. The supplement included questions to ascertain knowledge, beliefs, and attitudes and a food frequency questionnaire to ascertain nutrient intake.Statistics Multivariate linear regression modeling was conducted to assess the hypothesized relationships.Results After adjustment for relevant covariates (age, sex, education, total energy, perceived barriers to eating a more healthful diet), knowledge and belief constructs were predictive of dietary behavior. Specifically, fat, fiber, and fruit and vegetable intakes more closely approximated dietary recommendations for persons with more cancer-prevention knowledge. The strength of the associations between these constructs and dietary behavior varied in some cases according to level of education and perceived barriers to eating a healthful diet. Of the perceived barriers to eating a healthful diet, perceived ease of eating a healthful diet was most strongly and consistently predictive of intake.Conclusions Research findings challenge dietetics practitioners to design diet- and health-promotion programs and activities that not only educate the public about the importance of diet to health, but also address barriers to dietary change. 相似文献
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Influences on the Selection of Dietetics as a Career 总被引:1,自引:0,他引:1
Objective To gather information on the factors that influence students’ decisions to choose dietetics as a career.Design Self-administered questionnaires regarding the point at which career decisions were made were completed by 1,695 students in Plan IV/V dietetics programs throughout the United States.Subjects All Plan IV/V dietetics programs that reported greater than five graduates in the academic year 1989 to 1990 were selected from the 1990-1991 Directory of Dietetic Programs for the sample population. Of the 156 schools that were mailed questionnaires, responses were received from 84 schools (54%). Almost 90% of the students were women, 10.6% were men.Statistical analyses Data were analyzed using the Statistical Package for the Social Sciences. A χ2 analysis was used to examine the relationship between point of decision and factors that influenced career choice, including people who influence career choice.Results The majority of students (55%) questioned reported making their career decision in college. Students rated interest in nutrition (96.3%) and job enjoyment (93.8%) as factors that were important in their decision to pursue a career in dietetics. College catalogs were rated by 48.3% of the students as being either useful or very useful in helping them make their career selection. With respect to gender differences, women rated a diverse work environment as being very important to their career decision more frequently than men (χ2=15.44, P<.01). Women were more likely than men to rate part-time work opportunities as being very important (χ2=26.75, P<.001); and selected working with people as being very important to their career decision (χ2=17.59, P<.01).Conclusions Findings identified that recruitment strategies need to be audience specific. Because career decision making appears to occur during one of three time frames (high school, college, or work experience), recruitment activities should be developed to specifically target students at these times. One way to increase the exposure of students to the profession of dietetics is for registered dietitians to give guest lectures in introductory college courses and high school upper-class courses in health, home economics, and biology. The use of university/college catalogs as effective marketing tools should also not be underestimated.Data suggest that gender differences exist in factors that influence persons to choose dietetics as a career. To increase the number of men who pursue careers in dietetics, future research should be designed to more fully explore gender differences, so that strategies to recruit more men into the profession can be developed. J Am Diet Assoc. 1997: 97;254–257. 相似文献
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A study of the value of electrophoretic and other techniques for typing Acinetobacter calcoaceticus 总被引:1,自引:0,他引:1
Forty-four isolates of Acinetobacter calcoaceticus var anitratus collected during hospital outbreaks were studied using polyacrylamide gel electrophoresis (PAGE), plasmid analysis, antibiograms and biochemical tests to determine their degree of similarity. Reproducibility tests were also carried out on the PAGE and biochemical techniques to determine their validity when used to compare bacteria of the same type isolated intermittently. PAGE data was analysed densitometrically and isolates compared using a similarity matrix. All methods were able to subdivide the isolates, but results did not always correlate well between methods. Reproducibility data indicated that careful attention to technique is required when organisms are examined by PAGE sequentially. Results suggest that no single biotyping technique is likely to be adequate and that electrophoretic, biochemical and antibiogram data may complement one another and other epidemiological data in the typing of these organisms. 相似文献
70.
Budesonide versus prednisolone retention enemas in active distal ulcerative colitis 总被引:12,自引:4,他引:8
R. LÖFBERG O. ØSTERGAARD THOMSEN E. LANGHOLZ R. SCHIÖLER Å. DANIELSSON O. SUHR H. GRAFFNER L. PÅHLMAN P. MATZEN J. F. MØLLER-PETERSEN L. HALVORSEN N. HOVDENAK R. WILLEN T. PERSSON C. SEIDEGÅRD 《Alimentary pharmacology & therapeutics》1994,8(6):623-629
Methods: Efficacy and safety of the topically acting glucocorticosteroid budesonide retention enema (2.3 mg/ 11 5 mL) were compared with prednisolone disodium phosphate enema (31.25 mg/125 mL) in patients with active distal ulcerative colitis. The study was a randomized, multicentre trial, with two parallel groups and single-blind to the investigator. One hundred patients with active ulcerative colitis, not reaching beyond the splenic flexure as determined by endoscopy, were treated for up to 8 weeks. Results: Forty-five patients were randomized to receive budesonide and 5 5 to prednisolone. Both treatment groups improved significantly in terms of endoscopic and histological scoring during the study, but there were no statistically significant differences between the two groups. Clinical remission, defined as no more than three daily bowel movements without blood and endoscopically non-inflamed mucosa, was achieved in 16% of the patients in the budesonide group after four weeks and in 24% in the prednisolone group (N.S.). After 8 weeks treatment the clinical remission rate in the groups had increased to 36 % for budesonide and 47% for prednisolone (N.S.). Mean morning plasma cortisol levels were unchanged in the budesonide group, whereas they were significantly suppressed in the prednisolone group after 2, 4 and 8 weeks (P < 0.0001). Side effects were mild and rare in both groups. Conclusions: Treatment with budesonide enema in active distal ulcerative colitis was comparable, regarding efficacy, to treatment with conventional prednisolone enema. A prolongation of the treatment time from 4 to 8 weeks doubled the clinical remission rate in both groups. However, budesonide may be preferable to prednisolone since it causes less systemic effects as reflected by a lack of plasma cortisol suppression. 相似文献