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141.
Soy isoflavones, body composition, and physical performance 总被引:2,自引:0,他引:2
OBJECTIVES: Physiologic changes, occurring during the process of aging, can have serious health consequences, such as increased risk of chronic disease and disability. Decline in estradiol levels after menopause is hypothesized to contribute to this risk. Thus, hormone therapy (HT) might prevent or delay those changes. However, HT has serious side effects and alternative approaches are needed. METHODS: We performed a 12-month double-blind randomized trial comparing soy protein containing 99mg isoflavones (aglycone weights) with milk protein (placebo) daily in 202 postmenopausal women aged 60-75 years. Endpoints were body composition, and physical performance. Randomization resulted in reasonable well-balanced groups, 153 (76%) women completed the trial. Compliance was good (plasma genistein levels 55 +/- 101 and 1259 +/- 1610 nmol/L for placebo and soy group, respectively). The changes in the endpoints during the intervention period among the two intervention groups were analyzed. RESULTS: Body mass index (BMI) and waist-to-hip ratio did not change during intervention. Handgrip strength at the final visit was slightly worse in the soy group compared to the placebo group (-0.45 kg (95% C.I.: -2.5, 1.6 kg; p = 0.7), but this difference was not statistically significant. Self-reported functional status, mobility and physical performance, all slightly improved during intervention but there were no differences between the groups. CONCLUSIONS: The results of the present trial do not support the view that soy isoflavones have favorable effects on body composition and physical performance in postmenopausal women. 相似文献
142.
Linda M. Gerber Joseph E. Schwartz Peter L. Schnall Thomas G. Pickering 《American journal of human biology》1995,7(2):173-182
The extent to which the relationship between body fat and blood pressure either differs by sex or explains sex differences in blood pressure is examined. Estimates of the relationship of blood pressure to several measures of adiposity in men and women were obtained from a systematic review of the literature and tests of whether these relationships differ by sex were performed. Analysis of covariance (controlling for age and race) was used for both casual and ambulatory blood pressure in the Cornell Worksite Blood Pressure Study (N = 276). In general, most adiposity measures were significantly related to casual and ambulatory blood pressure in men and women. Subscapular skinfold thickness and body mass index exhibited the strongest associations. The vast majority of adiposity/blood pressure associations were not significantly different for men and women. Finally, sex differences in adiposity did not account for much of the sex difference observed in blood pressure. © 1995 Wiley-Liss, Inc. 相似文献
143.
Jensen J Brennesvik EO Bergersen H Oseland H Jebens E Brørs O 《Pflügers Archiv : European journal of physiology》2002,444(1-2):213-219
In the present study, the density of cell surface beta-adrenergic receptors was determined in different skeletal muscles using the hydrophilic ligand [3H]CGP 12177. The density of beta-adrenergic receptors was highest in the slow-twitch soleus muscle (32.8+/-0.9 fmol mg dw(-1)) and lowest in the fast-twitch glycolytic white gastrocnemius (10.4+/-0.5 fmol mg dw(-1)) beta-Adrenoceptor density correlated closely with the percentage of type-I fibres (r=0.979; P<0.0001) and inversely with the percentage of type-IIB fibres (r=696; P<0.03). Incubation with isoprenaline (10 microM) for 30 min decreased the density of beta-adrenergic receptors in the cell surface from 32.9+/-0.8 to 19.3+/-0.7 fmol mg dw(-1) in the soleus and from 16.8+/-1.0 to 12.0+/-0.7 fmol mg dw(-1) in the epitrochlearis. Internalisation appeared rapid (half-time less than 5 min). To study externalisation of beta-adrenergic receptors, soleus strips were incubated 30 min with 10 microM isoprenaline and then transferred to buffer without agonist. The first incubation reduced the density to approximately 50%, the subsequent incubation without agonist increased cell surface receptor density to approximately 80% of the initial density after 1 h. No further increase was observed over the next 2 h, suggesting that some of the receptors had been degraded. Insulin or contractile activity did not influence rate of externalisation. 相似文献
144.
Shankaran S Laptook AR Ehrenkranz RA Tyson JE McDonald SA Donovan EF Fanaroff AA Poole WK Wright LL Higgins RD Finer NN Carlo WA Duara S Oh W Cotten CM Stevenson DK Stoll BJ Lemons JA Guillet R Jobe AH;National Institute of Child Health Human Development Neonatal Research Network 《The New England journal of medicine》2005,353(15):1574-1584
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146.
Brief observations of mother-stimulated infant vocalizationwere perform ed during pediatric clinic visits on 4- to 6-month-oldinfants to determine whether mothers with positive attitudestoward the pregnancy and/or the in fant would have infants whovocalized more during clinic visits. Mothers with more positiveattitudes toward the pregnancy, assessed prenatally, had infantswho showed significantly more vocalization during clinic visitsat 5 months, 6 months, and the combination of 5 and 6 months.Mothers with more positive attitudes toward the infant had infantswho showed signcantly more vocalization at 4 months and thecombination of observations at 4 months and 6 months. Resultssuggest that brief observations of vocalization during clinicvisits may be useful as a rough index of the quality of themother-child interaction. 相似文献
147.
148.
149.
The present paper is focused on the relationship between psychological variables and health beliefs in 93 diabetic men. A Diabetes Health Belief Scale was used to assess general health motivation, treatment beneficial, severity, susceptibility, psychological barriers, cues to action, and structural elements. The psychological variables included two measures of locus of control, depression, somatization, interpersonal sensitivity, obsessive—compulsiveness, anxiety, self-esteem, and attitudes toward diabetes, doctor, and medical care. Ten of the 11 psychological variables were correlated with various aspects of health beliefs. This indicates the extent to which the health beliefs are enmeshed with the psychological dynamics of the person. It would seem important to take such a psychological profile into consideration when attempting to understand and even alter the health beliefs. 相似文献
150.
Russell Harris Linda S Kinsinger Sue Tolleson-Rinehart Anthony J Viera Georgette Dent 《Academic medicine》2008,83(4):371-377
In 1997, the Schools of Medicine and Public Health at the University of North Carolina at Chapel Hill (UNC) developed a formal MD-MPH program, called the Health Care and Prevention (HC&P) Program, located in the Public Health Leadership Program in the UNC School of Public Health. Since then, and especially since 2003, the number of UNC medical students taking a year out of their medical studies to pursue an MPH has increased dramatically. At present, more than 20% of UNC medical students enter an MPH program at some point between entering medical school and leaving for residency.The HC&P Program is designed to introduce clinicians to the population sciences and to create physicians who can think in both individual and population terms. The curriculum is a rigorous, 12-month program that includes a practicum experience and a master's paper. Several of the traditional MPH introductory courses have been redesigned to be more relevant to physicians. The program allows a maximum number of electives and places a value on flexibility so that students, together with faculty, can design the educational experience that best meets their needs. Many members of the faculty of the program themselves have both MD and MPH degrees, and some have dual appointments in the schools of medicine and public health.The authors have begun a longitudinal cohort study of program graduates and other medical graduates to understand the effect of the program on students' perceptions of their competency and their ability to exert leadership in various areas of population health. 相似文献