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101.
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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   
103.
The nutritional status of persons with HIV and AIDS [PWAs] is constantly challenged throughout the progression of the illness. Home-delivered meals programs for PWAs are rapidly developing across the country to address this problem among the growing population of people with HIV infection and AIDS. This study examined client socio-demographic characteristics (sex, age, ethnicity), types of services offered by these programs, organizational and financial criteria, and characteristics of survey respondents.Data for this study was obtained from 15 of the 17 known home-delivered meals programs for PWAs in the United States through an original, cross-sectional survey instrument conducted by telephone interview between March 1994 and May 1994.Results from this study show an increase in the number of minority populations who participate in these programs (36% African-American and 12% Hispanic vs. 51% Caucasian), as well as women (17.2%) and children (7%). Geographic location was an important determinant for program eligibility. The number of meals served weekly varied greatly (from 510 to 12,600 per week). Other significant services included nutrition counselling, newsletters, and holiday-basket programs. Enhancing service-delivery systems was one of the more prevalent high-priority concerns cited, especially with regard to food quality and safety.These results show that these programs are catering increasingly to minority populations, women and children, and that they are expanding their services to meet the growing needs of their client populations. These findings suggest that there is a greater need for meals and other home-based services for persons living with HIV and AIDS.This research was supported by the Massachusetts Department of Public Health.He formerly was Director of Elder Health at the Massachusetts Department of Public Health, Boston, MA; he is a founder and serves on the Board of Directors of Community Servings  相似文献   
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This report highlights the association between tuberous sclerosis and Wolff-Parkinson-White syndrome. Ten patients with concurrent diagnoses of Wolff-Parkinson-White syndrome and tuberous sclerosis were identified. Wolff-Parkinson-White syndrome presented early in life, nine cases being diagnosed in the first year. Eight of the 10 cases were male. In eight cases, the syndrome was associated with supraventricular tachycardias, and in nine with cardiac rhabdomyomata. One child died from cardiac failure secondary to obstruction of the left ventricular outflow tract by a rhabdomyoma. Five of nine survivors showed resolution of Wolff-Parkinson-White syndrome on follow up. The accessory pathway was localised in nine patients from surface electrocardiograms: six children had left sided pathways and three had right sided pathways.  相似文献   
105.
A comprehensive mutational scanning test for the p53 coding region based on multiplex PCR and two-dimensional DNA electrophoresis was designed and evaluated. In a 2-step multiplex PCR, the p53 coding region (exons 2-11) was amplified as a single 8646-bp fragment by long- distance PCR in step one. This fragment served as a template for the subsequent co-amplification of the individual exons in two multiplex groups in step two. The multiplex products were then separated, first on the basis of size in non-denaturant polyacrylamide gels and then on the basis of sequence by denaturing gradient gel electrophoresis (DGGE). Primers for optimal PCR, melting behavior and 2-D gel distribution were designed using a recently developed computer program. The resulting two-dimensional gene scanning (TDGS) test was evaluated by screening, in a blinded fashion, 29 coded DNA samples from Li- Fraumeni syndrome patients with previously identified germline mutations. All mutations were correctly detected. This assay provides an accurate, cost-effective and non-radioactive method for simultaneous mutational scanning of all p53 coding exons.   相似文献   
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Background: It has been reported that cystine and theanine, amino acids related to glutathione synthesis, have immunomodulatory effects, such as suppressing inflammation after strenuous exercise. In this study, we examined the effects of oral administration of cystine and theanine during the perioperative period as a pilot study. Methods: Forty‐three cases of distal gastrectomy for cancer conducted in our department were assigned to the cystine and theanine group (CT group) or to the placebo control group (P group), and a randomized, single‐blind, parallel‐group study was then performed. Cystine (700 mg) and theanine (280 mg) or a placebo was administered to participants for 10 continuous days (4 days before to 5 days after surgery). Changes in pre‐ and postoperative interleukin (IL)–6, C‐reactive protein (CRP), albumin, white blood cell (WBC) count, neutrophil count, total lymphocyte count, resting energy expenditure (REE), and body temperature were compared and examined. Results: Ten patients were excluded, leaving 33 patients in the study. The CT group had significantly lower IL‐6 values (postoperative day [POD] 4), CRP levels (POD 7), neutrophil counts (POD 4), and body temperatures (POD 5) than the P group (P < .05). In addition, REE in the P group peaked on day 1 (1.14 ± 0.16 [pre‐ and postoperative ratio]), whereas the CT group did not show any increase on POD 1 (0.99 ± 0.21, P < .05 vs P group). Conclusions: This study suggests that oral administration of cystine and theanine during the perioperative period may alleviate postgastrectomy inflammation and promote recovery after surgery.  相似文献   
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ObjectiveTo examine purchase patterns at fast-food restaurants and their relation to restaurant characteristics, customer characteristics, and use of calorie information.DesignCross-sectional survey.SettingFast-food restaurants in New York State.ParticipantsAdult fast-food restaurant customers (n = 1,094).Variables MeasuredRestaurant characteristics (fast-food chain type, presence of calorie labels, and poverty of location), participant characteristics (demographics, calorie knowledge, awareness, and use), and customer purchasing patterns (ordering low-calorie or no beverage, small or no fries, or < 3 items) were used as predictors of total calories purchased.AnalysisMultiple regression.ResultsIn a regression model including restaurant and customer characteristics, fast-food chain customer age, sex, calorie use, and calorie awareness were independently associated with total calories purchased (all P < .05; model R2 = .19). When 3 purchasing patterns were added to the model, calorie use (P = .005), but not calorie awareness, remained associated with total calories purchased. The 3 purchase patterns collectively accounted for the majority of variance in calorie totals (Δ model R2 = .40).Conclusions and ImplicationsPromoting use of calorie information, purchase strategies, and calorie awareness represents complementary ways to support lower-calorie choices at fast-food chains.  相似文献   
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