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The level of riboflavin intake that will correct riboflavin deficiency in seven non-pregnant and in twelve pregnant Filipino women was determined in order to reassess the adequacy of the current Recommended Dietary Allowance (RDA) for riboflavin in Filipinos. Increasing levels of riboflavin were given to the subjects who were rated as riboflavin-deficient based on an initial erythrocyte glutathione reductase activation coefficient (EGR-AC) of greater than or equal to 1.3 in screening. The minimum riboflavin requirement, defined as the intake of riboflavin required to achieve an EGR-AC of less than 1.3, was estimated from the regression of EGR-AC on riboflavin intake (mg/1000 kcal). The estimates of minimum riboflavin requirement from the non-pregnant women ranged from 0.16 to 0.42 with a mean of 0.35 +/- 0.09 (SD) mg/1000 kcal. For the pregnant subjects, the estimates of minimum riboflavin requirement ranged from 0.36 to 0.81 with a mean of 0.58 +/- 0.18 (SD) mg/1000 kcal. Adding 30% to the mean, to cover the upper limits of 97.5% of the population, the estimated RDA for non-pregnant women is 0.46/1000 kcal. This value is approximately equal to the 1976 Philippine RDA of 0.5 mg riboflavin/1000 kcal. For pregnant women, adding 30% to the mean minimum requirement of 0.58 mg/1000 kcal, the estimated RDA is 0.75 mg/1000 kcal or 1.75 mg/day computed at the energy allowance of 2350 kcal during pregnancy. This value is 25% higher than the current Philippine RDA of 1.4 mg/day for pregnant women.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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To investigate whether the secular trend for growth in Dutch children still exists, the Oosterwolde I study of 1980 was repeated in 1989. A persisting secular trend was visible for height while the z scores of body proportions show no change during the past 10 years, which suggests that there is no change in the timing of puberty.  相似文献   
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A retrospective review of post-delivery antibody records was performed at a teaching hospital and a community hospital to determine the frequency of new red cell alloantibody production and transfusion during pregnancy. If alloantibody was undetected at delivery, it was assumed that alloimmunization had not occurred. When antibody was detected, a chart review was performed to determine if the antibody was present at the beginning of the pregnancy or was newly produced during the pregnancy. A total of 17,568 pregnancies were reviewed. Antibody was detected at delivery in 948 (5.4%) cases, of which 89.5 percent (848/948) involved passive anti-D or clinically insignificant antibodies. The remaining 100 pregnancies involved clinically significant IgG antibodies. In 58 pregnancies, the antibody was detected in the first trimester, and in 42, new antibody production occurred during the pregnancy. Thus, the prevalence of new antibody production during pregnancy was 0.24 percent (95% confidence interval [CI], 0.17-0.32). Transfusion records indicated that the prevalence of transfusions during pregnancy was 0.09 percent (95% CI, 0.04-0.14). None of the women with new alloantibody formation during their pregnancies required transfusion; hence, new alloantibody production and the need for transfusion appear to be independent events. The probability of these events occurring together was 2.1 × 10(-6), or 1 in 500,000 deliveries.  相似文献   
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Impact of education for physicians on patient outcomes   总被引:4,自引:0,他引:4  
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The aim of this study was to investigate the test–retest (TRT) repeatability of various parametric quantification methods for [18F]Flortaucipir positron emission tomography (PET). We included eight subjects with dementia or mild cognitive impairment due to Alzheimer’s disease and six cognitively normal subjects. All underwent two 130-min dynamic [18F]Flortaucipir PET scans within 3 ± 1 weeks. Data were analyzed using reference region models receptor parametric mapping (RPM), simplified reference tissue method 2 (SRTM2) and reference logan (RLogan), as well as standardized uptake value ratios (SUVr, time intervals 40–60, 80–100 and 110–130 min post-injection) with cerebellar gray matter as reference region. We obtained distribution volume ratio or SUVr, first for all brain regions and then in three tau-specific regions-of-interest (ROIs). TRT repeatability (%) was defined as |retest–test|/(average (test + retest)) × 100. For all methods and across ROIs, TRT repeatability ranged from (median (IQR)) 0.84% (0.68–2.15) to 6.84% (2.99–11.50). TRT repeatability was good for all reference methods used, although semi-quantitative models (i.e. SUVr) performed marginally worse than quantitative models, for instance TRT repeatability of RPM: 1.98% (0.78–3.58) vs. SUVr80–100: 3.05% (1.28–5.52), p < 0.001. Furthermore, for SUVr80–100 and SUVr110–130, with higher average SUVr, more variation was observed. In conclusion, while TRT repeatability was good for all models used, quantitative methods performed slightly better than semi-quantitative methods.  相似文献   
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