110 research outputs found

    Far-field mapping of the longitudinal magnetic and electric optical fields

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    In this letter, we demonstrate the experimental mapping of the longitudinal magnetic and electric optical fields with a standard scanning microscope that involves a high numerical aperture far-field objective. The imaging concept relies upon the insertion of an azimuthal or a radial polarizer within the detection path of the microscope which acts as an optical electromagnetic filter aimed at transmitting selectively to the detector the signal from the magnetic or electric longitudinal fields present in the detection volume, respectively. The resulting system is thus versatile, non invasive, of high resolution, and shows high detection efficiencies. Magnetic optical properties of physical and biological micro and nano-structures may thus be revealed with a far-field microscope

    Predictors and outcome impact of perioperative serum sodium changes in a high-risk population.

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    BACKGROUND: The perioperative period may be associated with a marked neurohumoral stress response, significant fluid losses, and varied fluid replacement regimes. Acute changes in serum sodium concentration are therefore common, but predictors and outcomes of these changes have not been investigated in a large surgical population. METHODS: We carried out a retrospective cohort analysis of 27 068 in-patient non-cardiac surgical procedures in a tertiary teaching hospital setting. Data on preoperative conditions, perioperative events, hospital length of stay, and mortality were collected, along with preoperative and postoperative serum sodium measurements up to 7 days after surgery. Logistic regression was used to investigate the association between sodium changes and mortality, and to identify clinical characteristics associated with a deviation from baseline sodium >5 mmol litre(-1). RESULTS: Changes in sodium concentration >5 mmol litre(-1) were associated with increased mortality risk (adjusted odds ratio 1.49 for a decrease, 3.02 for an increase). Factors independently associated with a perioperative decrease in serum sodium concentration >5 mmol litre(-1) included age >60, diabetes mellitus, and the use of patient-controlled opioid analgesia. Factors associated with a similar increase were preoperative oxygen dependency, mechanical ventilation, central nervous system depression, non-elective surgery, and major operative haemorrhage. CONCLUSIONS: Maximum deviation from preoperative serum sodium value is associated with increased hospital mortality in patients undergoing in-patient non-cardiac surgery. Specific preoperative and perioperative factors are associated with significant serum sodium changes.This work was supported by the Cambridge University Division of Anaesthesia.This is the author accepted manuscript. The final version is available from Oxford University Press via http://dx.doi.org/10.1093/bja/aeu40

    Teatro na educação de crianças e adolescentes participantes de ensaio clínico

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    OBJETIVO: Analisar os efeitos de uma intervenção pedagógica na aprendizagem de crianças e adolescentes participantes de pesquisa clínica. MÉTODOS: Estudo quantitativo, quasi-experimental e longitudinal, parte de um conjunto de estudos envolvidos no teste de uma vacina contra ancilostomíase. Amostra por conveniência com 133 estudantes de dez a 17 anos, de ambos os sexos, da Escola Municipal de Maranhão, MG, Brasil, 2009. Utilizou-se um questionário estruturado aplicado pré e pós-intervenção. O dispositivo pedagógico foi o Teatro do Oprimido. As variáveis dependentes foram o conhecimento específico e global sobre pesquisa clínica e sobre verminoses; a variável independente foi a participação na intervenção educativa. RESULTADOS: Houve aumento do conhecimento sobre sinais e sintomas, susceptibilidade à reinfecção e modo de contágio da verminose após a intervenção educativa. Aumentaram acertos relativos à duração da pesquisa clínica, aos procedimentos previstos, à possibilidade de desistência da participação e de ocorrência de eventos adversos. Permaneceu a noção de que o propósito primário da pesquisa é terapêutico, embora tenha reduzido o percentual de participantes que associaram a pesquisa ao tratamento médico. O Teatro do Oprimido possibilitou que as discussões acerca da helmintose e da pesquisa clínica fossem contextualizadas e materializadas. Os sujeitos puderam se despojar ou reduzir suas representações prévias. CONCLUSÕES: A participação de crianças e adolescentes em ensaios clínicos deve ser precedida de intervenção educativa, já que indivíduos dessa faixa etária nem sequer reconhecem que têm direito a decidir por si próprios

    Biliary atresia

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    Biliary atresia (BA) is a rare disease characterised by a biliary obstruction of unknown origin that presents in the neonatal period. It is the most frequent surgical cause of cholestatic jaundice in this age group. BA occurs in approximately 1/18,000 live births in Western Europe. In the world, the reported incidence varies from 5/100,000 to 32/100,000 live births, and is highest in Asia and the Pacific region. Females are affected slightly more often than males. The common histopathological picture is one of inflammatory damage to the intra- and extrahepatic bile ducts with sclerosis and narrowing or even obliteration of the biliary tree. Untreated, this condition leads to cirrhosis and death within the first years of life. BA is not known to be a hereditary condition. No primary medical treatment is relevant for the management of BA. Once BA suspected, surgical intervention (Kasai portoenterostomy) should be performed as soon as possible as operations performed early in life is more likely to be successful. Liver transplantation may be needed later if the Kasai operation fails to restore the biliary flow or if cirrhotic complications occur. At present, approximately 90% of BA patients survive and the majority have normal quality of life
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