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991.
992.
Dietary Changes Favorably Affect Bone Remodeling in Older Adults 总被引:4,自引:0,他引:4
ROBERT P. HEANEY MD DAVID A. McCARRON MD BESS DAWSON-HUGHES MD SUZANNE OPARIL MD SARAH L. BERGA MD JUDITH S. STERN ScD SUSAN I. BARR PhD CLIFFORD J. ROSEN MD 《Journal of the American Dietetic Association》1999,99(10):1228-1233
OBJECTIVE: To determine whether dietary counseling to increase milk intake could produce useful changes in the calcium economy and what, if any, other nutrition-related changes might be produced. DESIGN: Randomized, open trial. SUBJECTS/SETTING: Two hundred four healthy men and women, aged 55 to 85 years, who habitually consumed fewer than 1.5 servings of dairy foods per day. Six academic health centers in the United States. INTERVENTION: Subjects were instructed to consume 3 servings per day of nonfat milk or 1% milk as a part of their daily diets, or to maintain their usual diets, for a 12-week intervention period, which followed 4 weeks of baseline observations. MAIN OUTCOME MEASURES: Energy and nutrient intake assessed from milk intake logs and 3-day food records; serum calciotrophic hormone levels at baseline and at 8 and 12 weeks; urinary excretion of calcium and N-telopeptide at 12 weeks. STATISTICAL ANALYSES: Repeated-measures analysis of variance. RESULTS: In the milk-supplemented group, calcium intake increased by 729 +/- 45 mg/day (mean +/- standard error), serum parathyroid hormone level decreased by approximately 9%, and urinary excretion of N-telopeptide, a bone resorption marker, decreased by 13%. Urine calcium excretion increased in milk-supplemented subjects by 21 +/- 7.6 mg/day (mean +/- standard error), less than half the amount predicted to be absorbed from the increment in calcium intake. All of these changes were significantly different from baseline values in the milk group and from the corresponding changes in the control group. Bone-specific alkaline phosphatase level (a bone formation marker) fell by approximately 9% in both groups. Serum level of insulin-like growth factor-1 (IGF-1) rose by 10% in the milk group (P < .001), and the level of insulin-like growth factor binding protein-4 (IGFBP-4) fell slightly (1.9%) in the milk group and rose significantly (7.9%) in the control group (P < .05). APPLICATIONS/CONCLUSIONS: The changes observed in the calcium economy through consumption of food sources of calcium are similar in kind and extent to those reported previously for calcium supplement tablets. The increase in IGF-1 level and the decrease in IBFBP-4 level are new observations that are beneficial for bone health. Important improvements in skeletal metabolism can feasibly occur in older adults by consumption of food sources of calcium. Dietitians can be confident that food works, and that desired calcium intakes can be achieved using food sources. 相似文献
993.
SOO-KYUNG LEE PhD RD JEFFEREY SOBAL PhD MPH EDWARD A FRONGILLO Jr PhD 《Journal of the American Dietetic Association》1999,99(9):1084-1089
OBJECTIVE: Examine variation in dietary practices and nutritional intakes of Korean Americans at different acculturation levels. DESIGN: Cross-sectional mail survey. SUBJECTS/SETTING: US national sample of 348 Korean Americans (46% of the Korean American sample to whom questionnaires were delivered). STATISTICAL ANALYSIS PERFORMED: Analysis of variance, Pearson correlation, Spearman rank correlation, chi 2 test, and multiple regression analysis. RESULTS: Korean Americans who were more acculturated consumed more American food and less Korean food. American foods such as oranges, low-fat milk, bagels, tomatoes, and bread were consumed regularly by Korean Americans; Korean foods such as rice, kimchi, garlic, green onions, and Korean soup were also consumed regularly. American foods were adopted the most at breakfast and the least at dinner. Bicultural people regularly incorporated more different types of foods into their diet. Despite significant differences in dietary practices, dietary quality did not vary by acculturation status. APPLICATION/CONCLUSIONS: Acculturation was influential in the dietary patterns of Korean Americans. Specific information about Korean diet related to acculturation status can be used by dietitians who work with Korean Americans. Dietitians can benefit from gathering and applying specific information about Korean diets and diets of other ethnic groups; they also need to recognize the changing nature of dietary patterns as acculturation occurs. 相似文献
994.
JEAN-XAVIER GUINARD PhD MS PAMELA J. SECHEVICH MS KATE MEAKER PhD SATYA S. JONNALAGADDA PhD PENNY KRIS-ETHERTON PhD MS RD 《Journal of the American Dietetic Association》1999,99(6):690
Objective To examine the effects of manipulating dietary fat in foods on sensitivity and hedonic response to fat in selected foods.Design Twenty subjects were randomly assigned to a sequence of three 8-week experimental diets (average American diet, step 1 diet, low-saturated-fat diet) that varied in energy from fat (37%, 30%, and 26%, respectively) and saturated fat (17%, 10%, and 6%, respectively). Subjects participated in sensory tests designed to assess their sensitivity to and liking for fat in several foods, before the study (baseline), after consumption of each diet, and after the study (washout).Subjects/setting Subjects were participants in the Dietary Effects on Lipoprotein and Thrombogenic Activity (DELTA) study.Results No significant differences were found among diets for difference thresholds (ie, just noticeable differences) for fat in milk and pudding, ad libitum mixing of low- and high-fat samples of milk and soup, and hedonic scaling of fat concentrations in milk and muffins and of cheese, mayonnaise, hot dog, and pastry samples.Applications/conclusions Within the dietary fat ranges and for the fat stimuli tested in this study, dietary fat as percentage of energy from fat and saturated fat was not a significant determinant of sensitivity to and/or liking for fat. Sensory factors should not be a barrier to the implementation of low-fat diets such as the step 1 and low-saturated-fat diets. J Am Diet Assoc. 1999;99:690–696. 相似文献
995.
Todd S Woodward M Tunstall-Pedoe H Bolton-Smith C 《American journal of epidemiology》1999,150(10):1073-1080
In this paper, data obtained between 1984 and 1993 from 11,629 men and women as part of the Scottish Heart Health Study (Scotland, United Kingdom) were used to investigate the relation between antioxidant vitamin and fiber intakes and both incident coronary heart disease (CHD) (649 events) and all-causes mortality (591 deaths). All age-adjusted mean intakes tended to be higher in the group that experienced no event. For men, increased fiber intake was associated with decreased risk of CHD even after adjustment for a host of other major coronary risk factors; hazard ratios relative to the lowest quarter were 0.68, 0.70, and 0.64 by increasing quarter. This relation was also observed for mortality (hazard ratios of 0.62, 0.66, and 0.62). Evidence was found that higher intakes of the antioxidants were also beneficial, although the associations were weaker. For women, fiber was the only obviously influential dietary factor, with hazard ratios of 0.94, 0.60, and 0.56 for CHD and 1.25, 0.82, and 0.65 for mortality. These results suggest that the current public health drive to increase the consumption of foods rich in antioxidant vitamins and (particularly) fiber will impact on both CHD risk and the general health of the population. 相似文献
996.
997.
Lawton E Leiter K Todd J Smith L 《Public health reports (Washington, D.C. : 1974)》1999,114(6):540-549
Welfare reform has drastically altered the lives of poor families in the US. In its wake, many former recipients are not receiving whatever transitional benefits and other safeguards to which they remain entitled under federal and state laws. Families are losing access to Medicaid and are not receiving the child care assistance or Food Stamps for which they continue to be eligible. Ill-served by stringent time limits and work requirements, lack of child care assistance, and lack of training and educational opportunities for the development of skills that will lead to better jobs, families need help to navigate the complexities of the new welfare system. Boston Medical Center's Department of Pediatrics has instituted a welfare screening project to educate families about their rights under welfare reform and assist them in advocating for themselves and their children. 相似文献
998.
The question of whether thyroxine (T4) and thyrotropin-releasing hormone (TRH) affect mitoses in pituitary thyrotrophs (Tt) and somatotrophs (St) of hypothyroid
rats was investigated. Fifteen day thyroidectomized (Tx) rats were used. Groups of Tx animals received T4 or TRH or both. Except 6 and 24 h TRH groups, the animals were sacrificed 12 h after injections. Unoperated euthyroid rats
served as controls. In Tx group adenohypophysial mitoses were significantly increased. T4 diminished mitoses in Tx rats. Mitotic counts were decreased in 6 and 24 h Tx groups, but increased in 12 h TRH group. TRH
plus T4 in Tx animals had a synergistic effect on adenohypophysial mitoses. In unoperated controls few mitoses were observed in Tt
and more mitoses in St. In Tx rats more mitoses were seen in Tt than in St. T4 alone failed to reduce mitoses in Tt but increased them in St. We concluded that T4 affects Tt and St replication. In normal rats mitoses occur mainly in St. In Tx rats mitotic activity increased in Tt. TRH
plus T4 have a synergistic motogenic effect on St. T4 but not TRH affects St replication. It appears that the presence, of T4 is necessary for St multiplication. 相似文献
999.
Inositol is a simple polyol precursor in a second messenger system important in brain myo-insitol, the natural isomer, which
has been found to be therapeutically effective in depression, panic disorder, and obsessive-compulsive disorder in double-blind
controlled trials. Recently, epiinositol, an unnatural stereoisomer of myo-inositol, was found to have effects similar to
those of myo-inositol to reverse lithium-pilocarpine seizures. We measured the behavior of rats in an elevated plus maze model
of anxiety after chronic treatment of 11 daily intraperitoneal injections of epi-inositol, myo-inositol, or control solution.
Epi-inositol reduced anxiety levels of rats compared with controls, and its effect was stronger than that of myoinositol.
Lithium has been hypothesized to alleviate mania by reducing brain inositol levels. Inositol in brain derives from the second
messenger cycle, from new synthesis, or from diet via transport across the blood brain barrier. Because the first two are
inhibited by lithium, we propose that an inositol-free diet will augment lithium action in mania by enhancing restriction
of inositol. 相似文献
1000.
G H Guyatt D J Cook L E Griffith J D Miller T R Todd M R Johnston T L Winton A G Casson R I Inculet G E Darling R J Finley J Deslauriers 《The Annals of thoracic surgery》1999,68(2):309-315
BACKGROUND: In patients with apparently operable non-small cell lung cancer (NSCLC), clinicians often omit investigation for M disease in asymptomatic patients. Previous investigations have not specified in detail what is meant by "symptomatic," and this could differ between surgeons. We have investigated the extent to which surgeons' criteria differ for presence of symptoms. METHODS: Participating surgeons from seven centers, enrolled patients they judged "asymptomatic" in a randomized trial of investigational strategies for NSCLC. Patients completed a structured questionnaire describing symptoms of the central nervous system (CNS). In 685 patients, we documented CNS symptom recurrence after resectional surgery over 1 year of follow-up. RESULTS: Two centers enrolled only patients without even the mildest symptoms. Three centers took an intermediate approach, occasionally classifying patients with mild symptoms as "asymptomatic" and thus enrolling them in the trial. Two centers classified an appreciable number of patients with minimal symptoms, and occasionally with more than minimal symptoms, as "asymptomatic." Patients with even mild CNS symptoms were more likely to subsequently present with CNS metastases. CONCLUSIONS: Thoracic surgeons differ in their ideas of what may constitute the symptoms of M disease. Patients with structured questionnaire results that suggest symptoms of CNS disease are more likely to have CNS symptom recurrence after resectional surgery. 相似文献