Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 12 de 12
Filtrar
Mais filtros

Bases de dados
País/Região como assunto
Tipo de documento
País de afiliação
Intervalo de ano de publicação
1.
Eur J Clin Nutr ; 66(3): 369-75, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21989324

RESUMO

BACKGROUND/OBJECTIVES: Lower-income subgroups consume fewer servings of fruit and vegetables (FVs) compared with their more advantaged counterparts. To overcome financial barriers, FV voucher delivery has been proposed. SUBJECTS/METHODS: In a 12-month trial, 302 low-income adults 18-60 years old (defined by evaluation of deprivation and inequalities in health examination centers, a specific deprivation score) were randomized into two groups: dietary advice alone ('advice'), or dietary advice plus FV vouchers ('FV vouchers') (10-40 euros/month) exchangeable for fresh fruits and vegetables. Self-reported data were collected on FV consumption and socioeconomic status at baseline, 3, 9 and 12 months. Anthropometric and blood pressure measurements were conducted at these periods, as well as blood samples obtained for determination of vitamins. Descriptive analyses, multiple linear regression and logistic regression were performed to evaluate the impact of FV. RESULTS: Between baseline and 3-month follow-up, mean FV consumption increased significantly in both the 'advice' (0.62±1.29 times/day, P=0.0004) and 'FV vouchers' groups (0.74±1.90, P=0.002), with no difference between groups. Subjects in the FV vouchers group had significantly decreased risk of low FV consumption (<1 time/day) compared with those in the advice group (P=0.008). No change was noted in vitamin levels (vitamin C and ß-carotene). The high number of lost-to-follow-up cases did not permit analysis at 9 or 12 months. CONCLUSION: In the low-income population, FV voucher delivery decreased the proportion of low FV consumers at 3 months. Longer-term studies are needed to assess their impact on nutritional status.


Assuntos
Dieta/economia , Serviços de Alimentação , Educação em Saúde , Renda , Pobreza , Classe Social , Seguridade Social , Adolescente , Adulto , Aconselhamento , Dieta/normas , Feminino , Abastecimento de Alimentos , Frutas , Humanos , Modelos Lineares , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Estado Nutricional , Autorrelato , Verduras , Adulto Jovem
2.
Med Phys ; 37(7): 3782-90, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20831086

RESUMO

PURPOSE: In this work, the authors describe an approach which has been developed to drive the application of different variance-reduction techniques to the Monte Carlo simulation of photon and electron transport in clinical accelerators. METHODS: The new approach considers the following techniques: Russian roulette, splitting, a modified version of the directional bremsstrahlung splitting, and the azimuthal particle redistribution. Their application is controlled by an ant colony algorithm based on an importance map. RESULTS: The procedure has been applied to radiosurgery beams. Specifically, the authors have calculated depth-dose profiles, off-axis ratios, and output factors, quantities usually considered in the commissioning of these beams. The agreement between Monte Carlo results and the corresponding measurements is within approximately 3%/0.3 mm for the central axis percentage depth dose and the dose profiles. The importance map generated in the calculation can be used to discuss simulation details in the different parts of the geometry in a simple way. The simulation CPU times are comparable to those needed within other approaches common in this field. CONCLUSIONS: The new approach is competitive with those previously used in this kind of problems (PSF generation or source models) and has some practical advantages that make it to be a good tool to simulate the radiation transport in problems where the quantities of interest are difficult to obtain because of low statistics.


Assuntos
Algoritmos , Formigas , Elétrons , Método de Monte Carlo , Fótons/uso terapêutico , Radiocirurgia , Animais , Doses de Radiação , Fatores de Tempo
3.
Ann Endocrinol (Paris) ; 62(6): 499-506, 2001 Dec.
Artigo em Francês | MEDLINE | ID: mdl-11845024

RESUMO

Thyroid nodules were assessed by ultrasound in 3 621 presumably healthy free-living French subjects participating in the SU.VI.MAX cohort (2 160 females aged 35-60 years and 1 461 males aged 45-60 years). Urinary iodine was measured in all participants in random morning urine samples. Nodular thyroid structures ranging from 3 mm to 57 mm in diameter were found in 14.5% of the population, without significant differences between regions in the different age and sex groups. Single nodules and multiple lesions were found in, respectively, 9.7% and 3.1% of the subjects. In females, nodules increased from 12.9% to 19.2% between 35-45 years and 45-60 years, respectively (p<0.001). Thyroid nodularity was more frequent among women aged 45-60 years than among men of those ages (19.2% vs. 11.0%, p=0.001). Descriptive data provided by ultrasound differentiated the nodules into solid (43.4%), cystic (38.4%), and mixed solid-cystic (18.2%). Most solid thyroid nodules, 76.1%, were hypoechoic, while 16.6% were iso-, and 7.3% were hyperechoic. The median of iodine concentrations (n=3 276) was 8.0 microgram/100 ml, with 19.4% of the samples being<5 microgram/100 ml. Median iodine concentrations displayed wide regional variations, with values significantly higher in residents of western regions than among those living in the eastern areas (p<0.001), independently of age and sex. No relationship was found between prevalence of nodular thyroid structure and the state of borderline iodine status observed in France.


Assuntos
Bócio Nodular/diagnóstico por imagem , Iodo/urina , Nódulo da Glândula Tireoide/diagnóstico por imagem , Adulto , Distribuição por Idade , Estudos de Coortes , Feminino , França/epidemiologia , Variação Genética , Bócio Nodular/epidemiologia , Humanos , Iodo/deficiência , Masculino , Pessoa de Meia-Idade , Prevalência , Fatores de Risco , Distribuição por Sexo , Nódulo da Glândula Tireoide/epidemiologia , Ultrassonografia
4.
Eur J Epidemiol ; 16(5): 477-82, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-10997836

RESUMO

The determinants of hormone replacement therapy (HRT) were studied in a cohort of recently postmenopausal women participating, in France, in a nutritional study (SU.VI.MAX Study). Analysis was performed-analysis on 592 women aged 45 years or more, who had undergone natural menopause which appeared in the 2 previous years. No differences were observed in education level, socio-professional categories, marital status, geographic residence, smoking habits, physical activity, or past contraceptive practice. Past regular gynecologic follow-up appeared to be the strongest determinant of HRT use (odds ratio [OR]: 3.18). Women who reported having had at least one of the studied pathologies (past history of breast cancer, phlebitis, anger, uterine fibroma, hypertension, diabetes or hypercholesterolemia), past abundant menstrual blood losses, and with body mass index (BMI) > or = 25 were less likely to be taking HRT than women free of pathology, with no history of past abundant menstrual blood losses and with low BMI (OR respectively of 0.40, 0.64, 0.62). Women over 51.3 years of age were less likely to use HRT than younger women (OR: 0.92). Finally, in our population, while socio-economic level was not a major determinant of HRT use, the regularity of gynecological follow-up before menopause, overweight, and the existence of a definite or possible contra-indication were strong determinants of HRT use.


Assuntos
Terapia de Reposição Hormonal , Fatores Etários , Índice de Massa Corporal , Estudos de Coortes , Contraindicações , Feminino , Humanos , Menorragia , Pessoa de Meia-Idade , Pós-Menopausa , Fatores Socioeconômicos
6.
Ann Nutr Metab ; 40(6): 331-5, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-9087311

RESUMO

The iron status of 22 children and adolescents with Crohn's disease (mean age: 13 years) was evaluated. Eleven patients were suffering from active disease with inflammation, identified by at least one abnormal value for serum orosomucoid, C-reactive protein or sedimentation rate (group I). Eleven patients were in clinical remission and showed no biological evidence of inflammation (group II). Hemoglobin and red cell indices, erythrocyte protoporphyrin, serum iron, transferrin, serum ferritin and basic red cell ferritin were determined in all patients. The usual indicators of iron status, particularly serum ferritin, were affected by the inflammatory processes, but basic red cell ferritin appeared to be independent of inflammation. Basic red cell ferritin can therefore be considered to be a reliable indicator of iron status in children and adolescents with Crohn's disease.


Assuntos
Doença de Crohn/sangue , Eritrócitos/metabolismo , Ferritinas/sangue , Ferro/sangue , Estado Nutricional , Adolescente , Sedimentação Sanguínea , Proteína C-Reativa/metabolismo , Criança , Pré-Escolar , Hemoglobinas/metabolismo , Humanos , Orosomucoide/metabolismo , Transferrina/metabolismo
7.
Rev Epidemiol Sante Publique ; 43(2): 139-46, 1995.
Artigo em Francês | MEDLINE | ID: mdl-7732200

RESUMO

In this paper, we try to understand the motivations and characteristics of people susceptible to be volunteers for the SU.VI.MAX study. The objective of this study will be to recruit and to follow during 8 years, a cohort of 15,000 subjects at a national level, for an intervention trial in the field of nutritional prevention. A short media campaign has been organised to recruit "1,000 volunteers to help to test and to validate tools specifically developed for the SU.VI.MAX study". In total, 15,789 subjects matching selection criteria answered to our invitation. All received a short questionnaire; 10,984 sent back correctly filled up questionnaires (70%) and 1005 were selected at random for a complete analysis. A lexical analysis of motivations disclosed 6 different groups organised in two poles. The pole of true altruists with a speech relative to notions such as "volunteers-benevolent" (7% of subjects), wishes to participate to a "humane task" (9% of subjects) or to progress of medical research (27% of subjects). The other pole corresponds to people interested personally by the theme of the project with 3 kinds of speech: personal past history (13% of subjects), interest for foods fortified with vitamins and/or minerals (19% of subjects) or for relationships between food consumption and health (22% of subjects).


Assuntos
Minerais , Motivação , Fenômenos Fisiológicos da Nutrição , Vitaminas , Voluntários , Adulto , Feminino , Nível de Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Distribuição Aleatória , Fatores Socioeconômicos , Inquéritos e Questionários
8.
Rev Epidemiol Sante Publique ; 39(2): 157-63, 1991.
Artigo em Francês | MEDLINE | ID: mdl-1866483

RESUMO

Blood donors are considered as a group with increased risk of iron deficiency. Therefore it seems particularly useful to have a simple screening test at one's disposal in blood centers to detect easily early iron deficiency. Erythrocyte protoporphyrin assay on an hematofluorometer is very easy and of a low cost. So we studied its diagnostic value on a sample of 285 blood donors (131 men and 154 women). Prevalence of iron deficiency, defined by the coexistence of, at least, two abnormal indicators (serum ferritin, transferrin saturation, erythrocyte protoporphyrin, mean corpuscular volume), was 5.6% in this sample; sensitivity of erythrocyte protoporphyrin used alone was 75% and its specificity was 91.5%. We used a decision analysis to evaluate the opportunity of screening with this test, accompanied where indicated by iron supplements. The results, though preliminary, suggest that erythrocyte protoporphyrin measurement could be of interest in screening blood donors for iron deficiency.


Assuntos
Anemia Hipocrômica/sangue , Doadores de Sangue , Eritrócitos/química , Protoporfirinas/sangue , Adolescente , Adulto , Árvores de Decisões , Volume de Eritrócitos , Feminino , Ferritinas/sangue , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Sensibilidade e Especificidade , Transferrina/química
9.
Clin Chim Acta ; 189(2): 159-62, 1990 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-2397598

RESUMO

Iron status was evaluated in 103 elderly institutionalized individuals using haemoglobin concentration, red cell indices, serum iron, serum transferrin, serum ferritin and basic red cell ferritin. Inflammatory processes were identified by measuring concentrations of orosomucoid and C-reactive protein in serum and leukocyte counts. Anaemia was present in 16.5% of the individuals. No serum ferritin values were in the range of depleted iron stores; however 6% of the elderly individuals presented basic red cell ferritin less than 3 attog/cell (3 x 10(-18) g/cell). Serum ferritin was positively correlated with markers of inflammation. Basic red cell ferritin measurement was not influenced by inflammation and may provide a reliable indicator of iron status in the elderly.


Assuntos
Eritrócitos/metabolismo , Ferritinas/sangue , Ferro/metabolismo , Idoso , Idoso de 80 Anos ou mais , Anemia/sangue , Proteína C-Reativa/análise , Feminino , Humanos , Inflamação/sangue , Contagem de Leucócitos , Masculino , Pessoa de Meia-Idade , Orosomucoide/análise
10.
Ann Nutr Metab ; 31(4): 237-44, 1987.
Artigo em Francês | MEDLINE | ID: mdl-3497608

RESUMO

We assessed the nutritional status of 302 menstruating women living in three urban, semi-rural and rural areas of eastern Algeria. The anthropometric data and the biochemical measurements (serum levels of total proteins, albumin, transferrin and prealbumin) have shown the absence of protein malnutrition and the evidence of problems of overweight, whatever the criterion used (body mass index or relative weight). There were no differences according to the residence. Anemia (defined by WHO references) was observed in 28% of urban women, 19% of semi-rural women and in 32% of rural women. Iron deficiency (defined by the association of serum ferritin level of 12 micrograms/l or less and transferrin saturation less than 15%) was observed in 29, 27 and 22% of the cases, respectively. Folate deficiency (defined by concentration of red blood cell folates of less than 100 micrograms/l) was observed in 48, 45 and 22% of cases, respectively. Finally, 81% of anemia were associated with biochemical evidence of iron and/or folate deficiency.


Assuntos
Distúrbios Nutricionais/epidemiologia , Estado Nutricional , População Rural , População Urbana , Adulto , Argélia , Anemia Hipocrômica/epidemiologia , Estudos Transversais , Feminino , Deficiência de Ácido Fólico/epidemiologia , Hemoglobinometria , Humanos , Pessoa de Meia-Idade , Obesidade/epidemiologia
11.
Rev Epidemiol Sante Publique ; 33(3): 228-39, 1985.
Artigo em Inglês | MEDLINE | ID: mdl-4081228

RESUMO

Iron deficiency constitutes a major problem of Public Health affecting 10 to 20% of the world population. Although developing countries are specially susceptible, developed countries are also at risk. The use of reliable indicators of iron status is essential for assessing the magnitude and the distribution of iron deficiency in populations, and for developing effective public health measures. In this paper, the different indicators of iron status are briefly reviewed. The signification of these indicators, as reflect of a change in different body iron compartmentalization is also presented. In addition, their limitations in epidemiological surveys have been evaluated. It appears that no single iron parameter monitors the entire spectrum of iron deficiency. A combination of indicators, depending on the objectives of the study, the characteristics of the study population and the working conditions is required to measure the body iron content of individuals and to evaluate the iron status of the population.


Assuntos
Anemia Hipocrômica/epidemiologia , Deficiências de Ferro , Adolescente , Adulto , Anemia Hipocrômica/diagnóstico , Anemia Hipocrômica/tratamento farmacológico , Criança , Pré-Escolar , Eritrócitos/metabolismo , Reações Falso-Negativas , Reações Falso-Positivas , Feminino , Ferritinas/sangue , Hematócrito , Hemoglobinometria , Humanos , Lactente , Ferro/metabolismo , Ferro/uso terapêutico , Masculino , Inquéritos Nutricionais , Gravidez , Protoporfirinas/sangue , Risco
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA