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991.
P Wolmarans A J Benadé T J Kotze A K Daubitzer M P Marais R Laubscher 《The American journal of clinical nutrition》1991,53(5):1171-1176
The effect of 6 wk of either red meat (RM) or fatty fish (FF) intake on plasma lipid concentrations in 28 free-living volunteers (12 males, 16 females) aged 22-45 y was investigated in this clinical crossover trial. Dietary intake was estimated by 7-d dietary records, and fasting blood samples were analyzed for plasma lipid concentrations. Although energy intake did not differ, protein intake was higher (P less than 0.01) in the FF period than in the RM period. There was also a difference (P less than 0.001) in the ratio of dietary polyunsaturated to saturated fatty acids in the RM (0.45) and FF (0.93) periods. Mean plasma total cholesterol, low-density-lipoprotein cholesterol, very-low-density-lipoprotein (VLDL) cholesterol VLDL-triacylglycerol, and plasma triacylglycerol concentrations were lower (P less than 0.001) in the FF than in the RM period. Positive correlations between animal-protein intake and plasma lipoproteins were observed. Atherogenic plasma lipoprotein concentrations were lower when FF was substituted for RM. 相似文献
992.
A M Schols E W Fredrix P B Soeters K R Westerterp E F Wouters 《The American journal of clinical nutrition》1991,54(6):983-987
Resting energy expenditure (REE) was measured in 68 patients with stable chronic obstructive pulmonary disease (COPD) and in 34 weight-stable, age-matched (65 +/- 8 y; means +/- SD) healthy control subjects. Fat-free mass (FFM) determined by bioelectrical resistance explained 84% of the variation in REE in the control group but only 34% in the COPD patients. REE could not reliably be predicted from regression equations either developed in healthy subjects or in COPD patients. REE adjusted for FFM was significantly higher (P less than 0.05) in weight-losing (n = 34) than in weight-stable (n = 34) patients (6851 +/- 781 and 6495 +/- 650 kJ/d, respectively). Pulmonary function was more compromised in weight-losing patients. Adjusted REE in weight-stable patients was significantly higher (P less than 0.01) than in the healthy control group (6131 +/- 405 kJ/d). In patients with COPD, factors in addition to FFM are important determinants of REE. A disease-related increase in REE develops, which may contribute to weight loss in COPD in combination with a lack of an adaptive response to undernutrition in weight-losing patients. 相似文献
993.
Nutrition labels in bar graph format deemed most useful for consumer purchase decisions using adaptive conjoint analysis 总被引:1,自引:1,他引:0
C J Geiger B W Wyse C R Parent R G Hansen 《Journal of the American Dietetic Association》1991,91(7):800-807
This study estimated the effects of changing multiple levels and combinations of nutrition information format, load, expression, and order on consumers' perceptions of label usefulness in purchase decisions using adaptive conjoint analysis. A shopping mall intercept survey, which was administered by a marketing research firm, assessed consumer preferences for 12 label alternatives produced on Campbell's soup cans to portray nutrition information realistically; 252 of 258 respondents completed the computer interactive interview. Consumers significantly preferred the bar graph format to the bar graph/nutrient density and traditional label formats. Consumers considered the bar graph/nutrient density format to be as useful as the traditional label format. There was a highly significant difference among the three levels of information load; the most information load was preferred regardless of nutrient importance. Consumers significantly preferred nutrition information stated in absolute numbers and percentages vs in absolute numbers only in traditional, or in percentages only expressions. There was a significant difference between consumer preferences for the two types of information order. The findings indicate that consumers clearly preferred the nutrition label that displayed all nutrient values using a bar graph format, offered the most information load, and expressed nutrient values using both absolute numbers and percentages. Consumers also preferred nutrition information rearranged in an order that grouped nutrients that should be consumed in adequate amounts on the top, calories in the middle, and nutrients that should be consumed in lesser amounts on the bottom of the label. 相似文献
994.
M P McMurry P N Hopkins R Gould K Engelbert-Fenton C Schumacher L L Wu R R Williams 《Journal of the American Dietetic Association》1991,91(1):57-65
We have developed a unique, family-oriented approach to lowering plasma cholesterol concentrations in persons with familial hyperlipidemias. The approach includes individual clinic visits and group nutrition classes and uses dietary goals outlined in The New American Diet. A series of 13 nutrition classes is presented to small groups, usually composed of relatives from pedigrees with familial hypercholesterolemia or other familial hyperlipidemias. Dietary action goals, cooking demonstrations, food tasting, and finger-stick plasma cholesterol determinations are important components of the classes. Problem-solving discussion is encouraged in the group. Over the past 4 years, 143 hyperlipidemic individuals, along with at least 94 unaffected family members, have participated in 31 groups, which have met for at least six classes. Many clinic participants lower plasma cholesterol by 20% or more. Keys to the success of this program include emphasizing dietary therapy, using the family setting for nutrition intervention, providing hands-on experience with food and recipes, promoting problem solving for dietary action goals, measuring blood cholesterol during classes, and encouraging long-term follow-up for participants with physicians and dietitians. 相似文献
995.
P M de Vries H B Folkers C W de Fijter J van der Meulen M Luitingh-van der Veen C Popp-Snijders L P Oe 《The American journal of clinical nutrition》1991,53(2):469-473
Adipose tissue fatty acid composition, serum lipid profile, and dietary intake of 37 patients on maintenance hemodialysis were studied. In August 1982, 1984, and 1986, analyses were carried out in 15 normotriglyceridemic (NTG) and 22 hypertriglyceridemic (HTG; type IV hyperlipidemia) patients. No correlations were found between dietary intake of polyunsaturated fatty acids (PUFAs), ratio of polyunsaturated to saturated fatty acids (P-S ratio), and carbohydrate content on the one hand and serum lipid concentrations on the other in the two groups. Adipose tissue linolenic acid correlated negatively with serum cholesterol in both groups. Strong correlations were found between dietary intake of PUFAs and adipose tissue linoleic acid content, between PUFAs and the double-bond index, between P-S ratio and adipose tissue linoleic acid content, and between P-S ratio and the double-bond index. No significant differences in dietary intake or adipose tissue fatty acid composition were observed between NTG and HTG patients. Thus, no evidence was found for exogenous dietary influences on serum lipid concentrations. The adipose tissue linoleic acid content did reflect the dietary intake of PUFAs. 相似文献
996.
To measure intestinal absorption by using a single, random stool sample, polyethylene glycol (PEG), 1 g/d, and a constant diet were given to healthy infants, with a constant PEG-to-macronutrient ratio. After 10 d equilibration, apparent intestinal absorption of macronutrients was estimated from a standard 3-d metabolic balance and compared with that estimated by using the ratio of PEG to macronutrients in a single random sample of feces. Correlation coefficients for this comparison were 0.649, 0.715, and 0.924 for nitrogen, carbohydrate, and fat, respectively. Additionally, apparent intestinal absorptions estimated from two separate consecutive 3-d metabolic-balance studies were compared, showing correlation coefficients of 0.106, 0.653, and 0.463 for nitrogen, carbohydrate, and fat, respectively. The random sample-marker technique appears to be acceptable for measuring apparent absorption of macronutrients and is at least as accurate as a standard 3-d metabolic-balance study. 相似文献
997.
Quantitative studies of morbidity, food intake, and somatic growth were done prospectively during 14 mo for 70 children aged 5-18 mo in two Bangladeshi villages. When random-effect regression models were used, monthly changes in weight were inversely related to proportions of days in the month with fever and diarrhea and positively related to energy intake per kilogram body weight. Interestingly, weight changes did not vary with age in this interval. Estimates indicate that increasing energy intakes to the recommended World Health Organization level would have a significantly greater effect on weight gain than would the elimination of diarrhea and fever. With energy at recommended intake and diarrhea and fever prevalence as found in US children, weight gain is predicted to be near that of the international reference population. Therefore, interventions aimed at improving dietary intake may be as important as infection-control programs for improving growth of children in poor developing nations. 相似文献
998.
We investigated the effect of oral contraceptives with low and high estrogen concentration on blood coagulation and thrombogenesis, induced by vascular subendothelium of rabbit aorta exposed to flowing human blood. Twenty healthy women intending to take oral contraceptives were studied [1] before drug ingestion (control), and subsequently during the intake of oral contraceptives with [2] low estrogen content (20 micrograms ethinyl estradiol and 150 micrograms desogestrel per day) and [3] high estrogen content (50 micrograms ethinyl estradiol and 125 micrograms desogestrel per day). All experiments were performed between day 17 and 21 of the menstrual cycle and drug effects were studied during the third tablet cycle. Deposition of fibrin, platelets and platelet thrombi on vascular subendothelium was tested at a defined blood flow and wall shear rate (10 ml/min, 650 s-1) and was quantified by morphometrical techniques. Treatment with the low and high dose contraceptive increased the plasma levels of ethinyl estradiol (728 +/- 139 and 1438 +/- 212 vs. 0 fmol/l [low and high dose vs. control], means +/- SEM, P less than 0.001) and fibrinogen (2.3 +/- 0.1 and 2.6 +/- 0.1 vs. 2.0 +/- 0.1 g/l, P less than 0.05); and decreased antithrombin III activity (95 +/- 3 and 92 +/- 3 vs. 101 +/- 3 %, P less than 0.05). Fibrin deposition on vascular subendothelium was enhanced by the high dose contraceptive only (47 +/- 4 vs. 35 +/- 4 % coverage of the subendothelial surface with fibrin, high dose vs. control, P less than 0.05). The subendothelial deposition of platelets and platelet thrombi was not changed by contraceptive treatment. These results indicate that treatment with high dose contraceptives leads to an increase of fibrin-subendothelial interactions, whereas low dose contraceptives do not significantly alter the blood-subendothelium interactions. observed in this ex vivo model of thrombogenesis. 相似文献
999.
Hypoxemia is associated with mitochondrial DNA damage and gene induction. Implications for cardiac disease 总被引:24,自引:0,他引:24
M Corral-Debrinski G Stepien J M Shoffner M T Lott K Kanter D C Wallace 《JAMA》1991,266(13):1812-1816
1000.
In 1984, in addition to its standard traditional curriculum, Rush Medical College (Chicago, Ill) developed a Socratic problem-based method of teaching basic science material called the alternative curriculum. As part of an evaluation of this new curriculum, students in the two curricula were compared using three traditional measurements: (1) test scores from the National Board of Medical Examiners, Part I; (2) test scores from the National Board of Medical Examiners, Part II; and (3) performance on an oral examination. Alternative curriculum students did not differ significantly from their traditional curriculum classmates on National Board of Medical Examiners, Part I and Part II total scores, although their subset scores on Part I did tend to be lower, reaching significance in one subset area. Differences in performance favoring the traditional curriculum were primarily seen in the early years of the program. Alternative curriculum students in the class matriculated in 1987 scored significantly higher in three of five categories on the oral examination. 相似文献