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The study has confirmed most risk/protective factors previously demonstrated elsewhere in the world and provides clear documentation of breast cancer epidemiology in Brazil.

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-Drought is considered the primary limitation to agriculture and, can reduce grain yield by up to 60% when occurs at pre-flowering in maize. In this context this research, aimed to understand the maize genotypes behavior to drought management and carbon partitioning between grain production and structures to maintain hydration when submitted to drought. Maize genotypes tolerant (DKB390 and P30F35) and sensitive (BRS1010 and 2B710) to drought were grown in a greenhouse using two water conditions: irrigated and stressed. Water deficit was imposed at pre-flowering and maintained for twelve days. Leaf water potential, gaseous exchange and male and female flowering interval were evaluated. At the end of the cycle, production components and root/shoot ratio dry weight were evaluated. Drought-tolerant genotypes used root system as a mechanism of tolerance to drought, which ensure greater efficiency in absorption and loss of water and, consequently, greater stomatal conductance during the drought, compared to the sensitive-genotypes. In addition, drought-tolerant genotypes showed greater stability in the source-sink relationship, exhibiting higher photosynthetic rate and harvest index. Keywords: water stress, carbon partitioning; root/shoot ratio dry weight, gas exchanges, Zea mays. GENÓTIPOS DE MILHO TOLERANTES À SECA INVESTEM EM SISTEMA RADICULAR E MANTEM ALTO ÍNDICE DE COLHEITA DURANTE O ESTRESSE HÍDRICORESUMO-A seca é considerada restrição primária à agricultura, e no milho, quando ocorre no pré-florescimento, pode reduzir o rendimento de grãos em até 60%. Neste contexto, objetivou-se entender como genótipos de milho contrastantes para tolerância à seca, gerenciam o particionamento de carbono entre produção de grãos e estruturas de manutenção da hidratação durante a seca. Para isso, em casa de vegetação cultivaram-se genótipos de milho tolerantes (DKB390 e P30F35) e sensíveis (BRS1010 e 2B710) à seca, em duas condições hídricas: irrigado normal e déficit hídrico. No pré-florecimento foi imposto o déficit hídrico, que foi mantido por doze dias. Posteriormente avaliou-se o potencial hídrico foliar, trocas gasosas e intervalo de florescimento masculino e feminino. No final do ciclo, avaliaram-se os componentes de produção e a razão raiz/parte aérea. Constatou-se que, genótipos tolerantes utilizaram preferencialmente sistema radicular como um mecanismo de tolerância à seca, o que garantiu a esses genótipos, maior eficiência entre a absorção e perda de água e, consequentemente, maior condutância estomática durante a seca, em relação aos genótipos sensíveis. Além disso, os genótipos tolerantes apresentaram maior equilíbrio em suas relações fonte e dreno, exibindo maiores taxa fotossintética e índice de colheita. Palavras-chave: estresse hídrico, particionamento de carbono, razão raiz/parte aérea, trocas gasosas, Zea mays. Sorgo, v.15, n.3, p. 451-461, 2016 ABSTRACT -Drought is considered the primary limitation to agriculture and, can reduce grain yield by up to 60% when occurs at pre-flowering in maize. In th...

Background: Much controversy has been generated about pre- and post-menopausal breast cancer patients and investigators have sought to identify whether risk factors differ between these two groups. In Brazil, breast cancer is an important cause of death among women and there are few analytical studies concerning pre- or post-menopausal comparisons. Methods: A case-control study was carried out at the Federal University Hospital, Belo Horizonte, Brazil, to determine if selected socio-economic and reproductive risk factors for breast cancer differed between pre-menopausal and post-menopausal women. Cases were 300 women with breast carcinoma and controls were 600 women with other benign diseases matched for age and date of diagnosis, admitted to the same hospital during the same period (1978–1987). Univariate and multivariate conditional logistic regression analyses were performed. Results: Multivariate analysis showed no differences in breast cancer risk in pre- and post-menopausal women (risk factors were similar in direction and magnitude). Occupation, irregular menstrual cycles, parity, history of breast cancer in at least one first-degree female relative, and oral contraceptive use had similar associations in both groups. Conclusions: The present study indicates that breast cancer diagnosed before and after menopause has a similar risk profile.