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881.
Previous studies indicate that crude oil leads to increased pigmentation and erythema (sunburn) in response to sunlight in exposed individuals. However, no information is currently available concerning whether crude oil exposure might enhance the immunosuppressive effects of solar ultraviolet radiation (UVR) on the skin. In order to address this question, the back skin of shaved, female C3H/HeN mice was exposed to crude oil with or without subsequent treatment with medium-wavelength (UVB) (200 J/m2) or long-wavelength (UVA) (20,000 J/m2) UVR. Immune function was assessed in treated mice by measuring their ability to mount contact hypersensitivity responses to a hapten (2,4-dinitro-1-flyorobenzene, DNGFB) applied to the site of crude oil and UVR treatment as determined by ear swelling upon subsequent challenge. Since Langerhans cells represent an important component of immunity within the skin and because suppression of contact hypersensitivity following UVR treatment is often accompanied by disappearance of Langerhans cells from the epidermis, the impact of these agents on epidermal Langerhans cell density was also analyzed. This was accomplished by enumerating IA-positive cells within the epidermis of treated skin. In these studies, crude oil alone induced inhibition of contact hypersensitivity but had no effect on epidermal Langerhans cells. In contrast, combined treatment with crude oil and UVA led to suppression of contact hypersensitivity, which was accompanied by depletion of epidermal Langerhans cells. 相似文献
882.
883.
A K Kant A Schatzkin G Block R G Ziegler M Nestle 《Journal of the American Dietetic Association》1991,91(12):1532-1537
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
884.
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
885.
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
886.
K Calder 《AARN news letter》1991,47(5):10-12
The use of programs to help administrators and staff of health care facilities assess and monitor the quality of services provided is not new. For years, quality assurance (QA) programs have provided generalized sets of standards against which hospitals and other agencies measure their performance. Recently, there has been a trend towards quality improvement (QI) programs which advocate a more proactive response to quality concerns and emphasize a decentralized use of assessment and evaluation findings to continuously improve the care provided. QI is recognized as holding great opportunities for the enhancement of professional nursing practice and the improvement of patient care. In this paper, the process and design of QI was described and the advantages of this approach were recognized. 相似文献
887.
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
888.
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
889.
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
890.
E R Monsen H Y Vanderpool C H Halsted K W McNutt H H Sandstead 《The American journal of clinical nutrition》1991,54(1):1-6
Body composition and measures of obesity were evaluated in 59 subjects with myelomeningocele (MMC), aged 0.3-29 y, by anthropometry and measures of body cell mass (BCM) and intra- and extracellular water (ICW and ECW), derived from total body potassium and deuterium-isotope dilution; these results were compared with reference data. Body composition was normal in preambulatory children with MMC. Beyond ages 3-4 y there was significant depletion of BCM and total body water, with maldistribution of water (increased ECW and decreased ICW) and increased percentage body fat above that expected for age and sex. These findings were more pronounced in females and in those with high lesions, and were less pronounced in those who remained ambulatory. These changes may result in metabolic and nutritional maladaption during stress. The relation of BCM, total body water depletion and increased ECW to decreasing ambulatory activity suggests that early nutritional and mobility programs warrant further study. 相似文献