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2.
Artigo em Inglês | LILACS | ID: lil-339345

RESUMO

High specific activity radioisotopes such as Lu-177, Pm-149, Ho-166 and Rh-105 can be produced by indirect methods involving neutron irradiation of isotopically enriched (e.g. Ru-104) targets producing parent radioisotopes that beta decay to form the desired daughter radioisotopes. For example, Lu-177 can be produced by direct (n, gamma) irradiation of Lu-176. However, only about 20 percent of the Lu-176 atoms are converted to Lu-177 and the long-lived impurity Lu-177m (half-life = 160 days) is also produced in small quantities. Direct irradiation of Yb-176 results in the production of Yb-177 (half-life = 1.9 hr) that beta decays to form Lu-177, with the further advantage that this route of production avoids long-lived Lu-177m. Chemical separation of the Lu-177 from the Yb target results in a high specific activity Lu-177 that can then be used for radiotherapy. Separation of Rh-105 from irradiated Ru-104 targets is also being investigated by volatilization of the Ru


Assuntos
Humanos , Radioterapia , Radioisótopos/provisão & distribuição
3.
NU Nytt Om U-Landshalsovard ; 6(3): 17-21, 1992.
Artigo em Inglês | AIM | ID: biblio-1266931

RESUMO

This paper presents a brief summary of vitamin A deficiency and xerophthalmia in Africa; and an overview of strategies for prevention and control. Indeed the epidemiological picture is complex in all dimensions. 18-20 countries in Sub-Saharan or Sahelian zones are estimated to have vitamin A deficiency problem of public health dimensions; and in a few more it is sporadically or occasionally present. Distribution of vitamin A supplements would be organized quite widely in Africa; especially in times of drought and emergencies


Assuntos
Saúde Pública , Deficiência de Vitamina A/prevenção & controle , Vitamina A/provisão & distribuição , Xeroftalmia/epidemiologia , Xeroftalmia/prevenção & controle
4.
Bull. W.H.O. (Online) ; 69(5): 561-571, 1991. ilus
Artigo em Inglês | AIM | ID: biblio-1259788

RESUMO

The objective was to evaluate the nutritional status of preschool children in the rural areas in order to establish a baseline for the measurement of the impact of a Government Nutrition Education Project (NUTED) in forthcoming years. The household cross-sectional survey was carried out on a representative sample of the rural population. The sample was stratified in order to portray the nutritional status of the children in the northern regions (more thinly populated) and in the southern regions: one stratum for small towns (between 2000 and 30,000 inhabitants) and 4 strata for rural localities. The sampling method used was by clusters of 30 children, distributed randomly in 20 zones per stratum. The nutritional indices of 2429 children were calculated and analysed according to WHO recommendations. The prevalence of the different types of malnutrition was 27.5% (95% confidence interval (CI), 24.2-30.8) for stunting (height-for-age retardation) and 5.5% (CI = 4.2-6.8) for wasting (weight-for-height retardation). Both types coexisted among 1.9% of the children; 23% of children were underweight for their age (CI = 21.6-26.2), and 15.8% (CI = 14.7-16.9) aged greater than 12 months had a mid-arm circumference below 135 mm. No sex difference was observed in the results. Stunting seems to appear in the second trimester of life (3-5 months), and wasting appeared between 9 and 23 months (highest rate between 12 and 17 months: 14.0% (CI = 9.3-18.8], which presents a real public health problem. The stratification did not show any significant differences in nutritional status among the children living in rural zones and those living in the small towns. However, the prevalence of malnutrition in the rural zones was 2 or 3 times higher than that observed in 1986 in Brazzaville. The division of the country into five main ecological zones allows some useful comparisons, e.g., the prevalence of stunting ranges from 15.5% (CI = 12.8-18.2) in the northern inundated forest zone to 38.8% (CI = 32.9-44.7) in the southern forests of Mayombe and Chaillu. The diet also varied, the frequency of animal protein consumption on the preceding day ranging from 76.3% to 59.1% in the different zones. The Republic of the Congo differs from other African countries in having relatively lower rates of stunting but an astonishingly high prevalence of wasting


Assuntos
Congo , Inquéritos Nutricionais , Estado Nutricional , Reprodutibilidade dos Testes , População Rural
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