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991.
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993.
Dietary Changes Favorably Affect Bone Remodeling in Older Adults   总被引:4,自引:0,他引:4  
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   
994.
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   
995.
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   
996.
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   
997.
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   
998.
999.
Background: The Swedish adjustable gastric band (SAGB) has been in use since 1985. The aim of this study was to analyze short and long-term complications linked to the SAGB. Materials and Methods: Between August 1990 and December 1996, we operated on a series of 326 patients (78 men and 248 women) at the Huddinge University Hospital and the Norra ?lvsborg County Hospital. The mean age of patients at surgery was 40 years (range 19-62). The mean preoperative weight was 125 kg (range 81-181). The mean excess weight was 80%. Results: The mean time of follow-up was 28 months (range 6-76). Complications requiring reoperation included two (0.6%) band dislocations, six (1.8%) band leakages, and 16 (4.6%) band migrations-erosions. The most common reason for abdominal reoperation, band migration, was attributed to overfilling of the band system. In the patients in whom migration occurred, the bands had been filled with a mean volume of 12.6 ml fluid. In the remaining patients, the mean volume was 8.7 ml. The most common complication not requiring reoperation was reflux disease (4.7%). In cases with a small pouch, this complication did not seem to be a serious problem. The mean excess weight loss in the 296 patients without complications was 68%. Conclusion: The overall long-term complication rate following SAGB is reasonable. With improved operating technique and closer follow-up, it should be possible to reduce the complication rate further. Reoperation because of band migration appears to be related to overfilling of the system and should therefore be avoidable in most cases.  相似文献   
1000.
Background: Breast reduction surgery is common in females; however, in males it is mainly due to gynecomastia. After weight reduction following obesity surgery, it is a problem in women, but also in some men. Method: One patient is described in whom the weight reduction declined from BMI 52 to BMI 36 after vertical banded gastroplasty, giving the patient ptotic breasts. Results: The patient underwent reduction mammaplasty with lateral single-based cutaneous flaps, and a total of 1,000 g was removed. Conclusion: Reduction mammoplasty can be performed in males with the methods used today, after successful weight loss following obesity surgery.  相似文献   
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