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991.
992.
The digestive and metabolic effects of inulin (from chicory) were studied in rats adapted to semipurified diets containing 0, 5, 10 or 20% inulin (wt/wt). Moderate levels of inulin (5-10%) did not significantly affect food intake or body weight gain. Dietary inulin resulted in considerably greater cecal fermentation and a significantly greater intraluminal concentration of propionate (peaking at 58.4 mmol/L). A lower concentration of acetate (42.6 mmol/L) was observed in rats fed 20% inulin. Lactic fermentations were observed in rats fed the 10 or 20% inulin diets. The cecal pool of volatile fatty acids tended to reach a plateau in rats fed diets containing more than 10% inulin (up to 600-700 mumol), but volatile fatty acid absorption was a slightly hyperbolic function of the dietary inulin level. Butyrate absorption was proportionally lower than that of propionate. Inulin-containing diets induced an enlargement of the cecal pool of calcium, phosphate and (to a lesser extent) magnesium. There was also an enhanced absorption of these divalent cations. The cecal pool of bile acids was greater in rats fed inulin, and this oligosaccharide displayed a slight hypocholesterolemic effect, even in rats fed the 5% inulin diet. However, plasma triglycerides were depressed only in rats fed the 20% inulin diet. In conclusion, inulin seems very effective in promoting propionic fermentation and in enhancing the calcium content of the large intestine. However, high levels of inulin (greater than 10%) may affect growth in rats and lead to acidic (pH 5.65) cecal fermentation.  相似文献   
993.
Accumulation of 64Cu in the 14-d mouse fetus was measured following intravenous injection of the dam with 64CuHis2. Concentration of 64Cu in the placenta increased rapidly over the first 4 h, thereafter remaining constant. Transfer to the fetus was linear over 48 h with little evidence of storage in the liver. Maternal serum levels decreased initially, concurrently with increased 64Cu levels in the maternal liver, but did not subsequently increase. Immediately following injection, as much as 40% of the radioactivity was in the nonalbumin fraction, and approximately 37% of that fraction (18% of total) was greater than 30,000 molecular weight. After 24 h, up to 60% of the 64Cu was still found in the albumin peak. The data suggest that the fetus can obtain its Cu from maternal ceruloplasmin but does not exclude the possibility that transfer occurs from the exchangeable (albumin/amino acid) Cu pool of the maternal plasma. In a second experiment, mice at different stages of gestation were injected with 64Cu and killed 4 h later. Total Cu levels and 64Cu uptake into the maternal tissues or into the placenta did not change with increasing gestation. Both total Cu and 64Cu uptake in the fetus and fetal liver increased to a maximum on d 16. Levels in the liver decreased thereafter to term, whereas levels in the rest of the fetus remained approximately constant. The pattern was similar whether the results were expressed per organ or per gram of fresh weight.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
994.
We developed a method for evaluating food group intake patterns using dietary recall data (n = 11,529) from the second National Health and Nutrition Examination Survey. We used this method to examine the relationship of these food group intake patterns to nutrient intake and to selected biochemical indexes of nutritional status. We evaluated each 24-hour dietary intake recall for the presence or omission of five broad food groups--dairy, meat, grain, fruit, and vegetable. The five most prevalent patterns and the proportion of the population reporting them was as follows: all food groups, 33.6%; no fruit, 23.9%; no dairy and fruit, 9.0%; no dairy, 8.0%; and no fruit and vegetable, 5.6%. In the most prevalent pattern, all food groups were consumed; this was the only pattern that provided mean amounts of all of the key vitamins and minerals at levels greater than or equal to the Recommended Dietary Allowances (RDAs). This pattern also was reported by the lowest proportion of individuals consuming less than 100% RDA of the key nutrients. Patterns in which both fruit and vegetables were consumed were associated with highest levels of serum vitamin C. The consistency of these results indicates that screening diets for food group consumption can quickly provide meaningful information about their quality.  相似文献   
995.
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   
996.
Serum lipoproteins, body composition, and adipose cholesterol contents of six obese women were studied during and after major weight loss by very-low-calorie diets (VLCDs). Subjects started at 168 +/- 11% of ideal body weight, lost 30.3 +/- 3.7 kg in 5-7 mo, followed by 2+ mo in weight maintenance. Serum cholesterol fell from a prediet (baseline) value of 5.49 +/- 0.32 to 3.62 +/- 0.31 mmol/L (P less than 0.01) after 1-2 mo of VLCDs (nadir), after which it rose to 5.95 +/- 0.36 mmol/L (peak, P less than 0.01 compared with nadir and baseline) as weight loss continued. With weight maintenance, serum cholesterol fell to 4.92 +/- 0.34 mmol/L (P less than 0.05 compared with peak). Adipose cholesterol content did not change in peripheral (arm and leg) biopsy sites but rose significantly in abdominal adipose tissue with weight loss. We conclude that major weight loss was associated with a late rise in serum cholesterol, possibly from mobilization of adipose cholesterol stores, which resolved when weight loss ceased.  相似文献   
997.
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   
998.
Weight loss in women participating in a randomized trial of low-fat diets   总被引:2,自引:0,他引:2  
We examined weight changes over 1 and 2 y in 303 women enrolled in a low-fat dietary-intervention trial. Participants were randomly assigned to an intervention group that received intensive instruction in maintaining a low-fat diet or to a control group. After 1 y intervention-group women had decreased fat intake by 45.3 g (from 39.2% to 21.6% energy from fat) and weight by 3.1 kg (all P less than 0.0001); control-group women decreased fat intake by 8.8 g (from 38.9% to 37.3% energy from fat) and weight by 0.4 kg. In both univariate analyses and multivariate models, weight loss was more strongly associated with change in percent energy from fat than with change in total energy intake. These data, which are consistent with both epidemiologic and clinical studies, suggest that body adiposity is a function both of energy balance and the proportion of energy derived from fat.  相似文献   
999.
Plasma lecithin-cholesterol acyltransferase (LCAT) activity, lipoprotein composition, and lipoprotein concentrations were measured in 21 children with kwashiorkor before (day 1), during (day 10), and after treatment (day 30). Day 1 LCAT activity (78.2 mumol.L-1.h-1) was decreased with respect to day 10 (139.2 mumol.L-1.h-1, P less than 0.001) and day 30 (108.0 mumol.L-1.h-1, P = 0.08). Plasma total cholesterol (TC), cholesterol ester (CE), and lipoprotein CEs (VLDL, IDL, LDL, and HDL) were reduced relative to days 10 and 30 (P less than 0.001). Before treatment HDL composition was abnormal. On days 1, 10, and 30, the respective mean HDL-apolipoprotein A-I (apo A-I) concentrations were 23.33, 39.66, and 36.08 mumol/L. LDL-apo B concentrations were 0.40, 0.68, and 0.56 mumol/L (P less than 0.01, days 10 and 30 vs day 1). LDL particles on day 1 were decreased in number, depleted of CE, and laden with triacylglycerol and surface lipids. LCAT activity on day 1 correlated with LDL-CE linoleate (P less than 0.05, r = 0.48). Reduced plasma LCAT activity is an important factor related to abnormalities in lipoprotein composition and concentrations.  相似文献   
1000.
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   
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