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1.
We have measured systolic and diastolic blood pressure and excretions of sodium, potassium, calcium and magnesium in groups of about 50 8- and 9-year-old boys from 19 European centres using standardized methods for the measurement of blood pressure and collection of urine, and by carrying out all analyses in one laboratory. Weight, height, pulse rate and environmental temperature were also studied. Mean systolic blood pressure ranged from 91 to 105 mm Hg and diastolic blood pressure from 51 to 66 mm Hg. Mean 24-h excretion of sodium was between 91 and 146 mmol/d, that of potassium between 29 and 60 mmol/d, that of calcium between 1.5 and 2.6 mmol/d and that of magnesium between 2.7 and 4.2 mmol/d. Mean sodium excretion tended to be lower and potassium excretion tended to be higher in the boys from the north-western parts of Europe. Relations between either systolic or diastolic blood pressure and electrolyte excretions were generally weak or absent. Most remarkable is that only the association between mean diastolic blood pressure and 24-h magnesium excretion (partial regression coefficient (b +/- s.e., -5.04 +/- 2.08 mm Hg/mmol/d) was statistically significant after adjusting for differences in creatinine excretion and environmental temperature. Mean systolic blood pressure was not significantly related with any of the variables measured. The partial regression coefficient (b +/- s.e.) for diastolic blood pressure on weight was 0.186 +/- 0.062 mm Hg/kg, on height 0.165 +/- 0.056 mm Hg/cm, on pulse rate 0.364 +/- 0.100 mm Hg/beats per min and on outside temperature -0.25 +/- 0.07 mm Hg/degrees C.  相似文献   
2.
Body composition of 24 rural Beninese women was assessed in a pre- and a postharvest season by using skinfold-thickness measurements, bioelectrical-impedance analysis (BIA), and deuterium oxide (D2O) dilution. Fat mass assessed by D2O dilution was 12.3 +/- 3.3 kg; by skinfold-thickness measurements, 13.8 +/- 3.3 kg; and by BIA, 14.1 +/- 2.9 kg. Fat mass assessed by D2O was significantly lower (P less than 0.05) than fat mass assessed by the other two methods. Body weight in the postharvest season was 0.8 +/- 1.6 kg higher (P less than 0.05) than during the preharvest season. All three methods demonstrated that there were no significant changes in fat mass but that fat-free mass increased significantly (P less than 0.05) from pre- to postharvest season.  相似文献   
3.
OBJECTIVE: The aim of this study was to assess the quality of diet of rural Zambian pre-school children, and to compare the dietary intake of stunted and non-stunted children. DESIGN: Cross-sectional study, in which dietary intake was assessed with a 24-h recall method. Height and weight were measured according to standard procedures. SETTING: Twelve villages in Samfya District, Zambia. SUBJECTS: Children aged 6-9 months ('infants') and 14-20 months ('toddlers'), attending Mother-and-Child Health Clinics, were eligible for study. Excluded were: 12 wasted, and 18 for other reasons. In total 106 infants and 99 toddlers were included. RESULTS: In infants and toddlers, total daily intake of energy, calcium, iron, and vitamin A was insufficient compared to recommended daily intakes. Only infants had insufficient protein intake. Compared to intake from weaning foods, breast milk was the main source of energy and most nutrients for infants. For toddlers, weaning foods were more important. Stunted infants and toddlers tended to have lower intakes of energy compared to non-stunted age-mates. Daily energy intake per kg bodyweight showed no difference between stunted and non-stunted children. CONCLUSIONS: Overall quality of weaning foods was inadequate. Stunted infants and toddlers showed a tendency of lower energy intakes compared to non-stunted age-mates.  相似文献   
4.
Serum samples were collected from 7- and 8-year-old boys in 16 countries with different rates of coronary heart disease (CHD) mortality. Both serum total and high-density lipoprotein (HDL) cholesterols were lower in developing countries than in affluent countries. The mean of the HDL cholesterol/total cholesterol ratio varied within narrow limits: 0.24-0.27 in Asian countries, 0.30-0.36 in Africa, and 0.30-0.37 in the USA and Europe. Thus both total and HDL cholesterol increased under the influence of a more affluent diet. This conclusion is supported by results from controlled trials. Student volunteers received all their food from us for periods of 8 to 16 weeks. Diets were prepared from regular foodstuffs, in such a way that they differed in one nutrient only. Dietary composition was confirmed by double portion analysis. A moderate fat diet with a high P/S ratio was compared with a low-fat, low-PUFA diet and with two high-fat diets having a high or low P/S ratio. Both low-fat and high P/S diets effectively lowered total serum cholesterol. However, HDL was depressed by the low-fat diet in comparison with diets with a higher fat content, whether high or low in polyunsaturates. This difference in HDL persisted for at least 3 months. This suggests that "Western" diets, usually high in fat, elevate both total and HDL cholesterol concentrations in children and young adults.  相似文献   
5.
Dietary factors that affect the bioavailability of carotenoids   总被引:14,自引:0,他引:14  
Carotenoids are thought to contribute to the beneficial effects of increased vegetable consumption. Various dietary factors have an effect on the bioavailability of carotenoids. The type of food matrix in which carotenoids are located is a major factor. The bioavailability of beta-carotene from vegetables in particular has been shown to be low (14% from mixed vegetables) compared with that of purified beta-carotene added to a simple matrix (e.g., salad dressing), whereas for lutein, the difference is much smaller (relative bioavailability of 67% from mixed vegetables). Processing, such as mechanical homogenization or heat treatment, has the potential to enhance the bioavailability of carotenoids from vegetables (from 18% to a sixfold increase). The amount of dietary fat required to ensure carotenoid absorption seems low (approximately 3-5 g per meal), although it depends on the physicochemical characteristics of the carotenoids ingested. Unabsorbable, fat-soluble compounds reduce carotenoid absorption, and interaction among carotenoids may also result in a reduced carotenoid bioavailability. Research into the functional benefits of carotenoids should consider the fact that the bioavailability of beta-carotene in particular is one order of magnitude higher when provided as a pure compound added to foods than when it is present naturally in foods.  相似文献   
6.
Samples of 38-year-old women were randomly selected from five European centers: Ede (The Netherlands), Warsaw (Poland), Gothenburg (Sweden), Verona (northern Italy), and Afragola (Naples-southern Italy). In total, 452 healthy women were studied. Anthropometric measurements were taken by one operator in each country after common training of all operators and blood parameters of all women were determined in one laboratory. Body mass index (BMI) was different among centers, mainly due to the higher values in southern Italy. Women from southern Europe had more central fat distribution than women from north European centers. Fasting serum insulin was higher in women from Poland and The Netherlands than in the other three centers. After adjustment for BMI, fasting insulin was significantly related to subscapular skinfold, subscapular to triceps skinfold ratio, waist circumference, and waist to thigh circumference ratio, although the partial correlations varied somewhat between the centers. In the pooled data, waist circumference showed the highest correlations with fasting serum insulin when adjusted for BMI. Fasting serum insulin showed significant partial correlations, adjusted for BMI, with lipid profile and blood pressure only in women from the two Italian centers. In the pooled data, fasting serum insulin was significantly positively correlated with serum triglycerides and total cholesterol and negatively to high-density lipoprotein (HDL) cholesterol and HDL/total cholesterol, independently of BMI and waist circumference. While blood pressure was not related to insulin in the pooled women, when adjusted for BMI and waist circumference; here as well, there were some differences in relationships between the centers.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
7.
8.
The purpose of this study is to enable high spatial resolution voxel‐wise quantitative analysis of myocardial perfusion in dynamic contrast‐enhanced cardiovascular MR, in particular by finding the most favorable quantification algorithm in this context. Four deconvolution algorithms—Fermi function modeling, deconvolution using B‐spline basis, deconvolution using exponential basis, and autoregressive moving average modeling —were tested to calculate voxel‐wise perfusion estimates. The algorithms were developed on synthetic data and validated against a true gold‐standard using a hardware perfusion phantom. The accuracy of each method was assessed for different levels of spatial averaging and perfusion rate. Finally, voxel‐wise analysis was used to generate high resolution perfusion maps on real data acquired from five patients with suspected coronary artery disease and two healthy volunteers. On both synthetic and perfusion phantom data, the B‐spline method had the highest error in estimation of myocardial blood flow. The autoregressive moving average modeling and exponential methods gave accurate estimates of myocardial blood flow. The Fermi model was the most robust method to noise. Both simulations and maps in the patients and hardware phantom showed that voxel‐wise quantification of myocardium perfusion is feasible and can be used to detect abnormal regions. Magn Reson Med, 2012. © 2012 Wiley Periodicals, Inc.  相似文献   
9.
OBJECTIVE: To investigate whether supplementation with vitamin A together with iron of Indonesian pregnant women decreases morbidity and improves growth of their infants during the first year of life. DESIGN: Women from a rural area in West Java, Indonesia, were randomly assigned on an individual basis to double-blind supplementation once weekly from approximately 18 weeks of pregnancy until delivery. Supplementation comprised 120 mg iron and 500 microg folic acid with or without 4800 RE vitamin A. Their newborn infants were followed up during the first year of life: weight, length, morbidity and food intake were assessed monthly. RESULTS: Infants whose mothers had taken vitamin A supplements during pregnancy had similar weight, length, weight gain and growth as their counterparts during the follow-up period. The proportions of infants with reported symptoms of morbidity were similar in the vitamin A plus iron group and the iron group. In addition immunisation coverage and feeding mode did not differ between the groups. All infants were breast-fed, but exclusive breast-feeding rapidly declined at 4 months of age. Infants with serum retinol concentrations >0.70 micromol/l increased their weight and length more during the first 6 months of life and had higher weight-for-age Z-scores during the first year of life than infants with serum retinol concentrations 相似文献   
10.
The study was conducted to look at the effectiveness of a multimicronutrient-fortified complementary food on the micronutrient status, linear growth and psychomotor development of 6- to 12-month-old infants from a black urban disadvantaged community in the Western Cape, South Africa. The study was designed as an intervention study. In both the experimental and control groups, serum retinol concentration showed a decline over the intervention period of 6 months. The decline was less pronounced in the experimental group. This resulted in a significantly (P<005) higher serum retinol concentration at 12 months in the experimental group (26.8+/-5.8 microg/dl) compared with the control group (21.4+/-5 microg/dl). Serum iron concentration also declined over the intervention period. The decline was less pronounced in the experimental group. No difference was observed in haemoglobin levels between the groups at 12 months. Serum zinc concentration did not differ significantly between the two groups at follow up. Weight gain over the 6 months period did not differ significantly between the experimental (2.1+/-0.9 kg) and control groups (2.1+/-1.2 kg). There was no difference in linear growth between the experimental (10.0+/-1.5 cm) and control group (10.1+/-2.1 cm) at the end of the follow-up period. Weight and length at 6 months significantly predicted weight and length at 12 months. No difference was observed in psychomotor developmental scores between the two groups after 6 months of intervention. Introducing a multimicronutrient-fortified complementary food into the diet of 6- to 12-month-old infants seemed to have an arresting effect on declining serum retinol and iron concentration in the experimental group. No benefit was observed in serum zinc concentration, linear growth and psychomotor development.  相似文献   
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