113 research outputs found

    Analyse des délais de prise en charge des cancers thoraciques : étude prospective

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    RésuméIntroductionLe cancer broncho-pulmonaire est la première cause de décès par cancer en France. Son diagnostic est le plus souvent tardif, alors que le délai entre le début des symptômes et la prise en charge est considéré comme un facteur aggravant.Matériel et méthodesNotre étude prospective a recueilli les différentes dates de prise en charge de 139 patients consécutifs bénéficiant d’un traitement primaire pour un cancer thoracique dans notre hôpital entre novembre 2008 et mai 2009. L’objectif de cette étude était d’évaluer différents délais de prise en charge des patients porteurs d’un cancer thoracique quelle que soit sa prise en charge thérapeutique (médicale ou chirurgicale) et de déterminer la cause de ces délais.RésultatsLe délai médian entre la première imagerie pathologique et le traitement est de 9,6 semaines. Les délais étaient significativement plus courts dans les stades tardifs et les carcinomes à petites cellules (p=0,001). Il existait une tendance à des délais plus courts pour les femmes et des délais plus longs pour les classes d’âge les plus élevées.ConclusionL’évaluation des délais de prise en charge, en particulier pour les stades précoces, s’intègre dans le contrôle de la qualité de prise en charge de ces pathologies.SummaryIntroductionLung cancer is the main cause of cancer death in France. The diagnosis is often late and the delay between the onset of symptoms and management is considered an aggravating factor.Material and methodsOur prospective study collected the dates of the start of management of 139 consecutive patients receiving first line treatment for thoracic cancer in our hospital between November 2008 and May 2009. The aim of this study was to evaluate the delays in medical or surgical treatments in patients with thoracic cancer and to determine the cause of these delays.ResultsThe median delay between the first abnormal chest X-ray and treatment was 9.6 weeks. The delays were significantly shorter in the late stages and in small cell cancer (P=0.001). There was a tendency for shorter delays in women and for longer delays in older patients.ConclusionEvaluation of the delays in treatment, particularly in the early stages, is part of the quality control of management of these diseases

    Variation in amine composition in plant species: how it integrates macroevolutionary and environmental signals.

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    Premise of the study: While plants show lineage-specific differences in metabolite composition, plant metabolites are also known to vary in response to the environment. The extent to which these different determinants of metabolite composition are mutually independent and recognizable is unknown. Moreover, the extent to which the metabolome can reconcile evolutionary constraint with the needs of the plant for rapid environmental response is unknown. We investigated these questions in plant species representing different phylogenetic lineages and growing in different subantarctic island environments. We studied their amines—metabolites involved in plant response to environmental conditions. • Methods: Nine species were sampled under high salinity, water saturation, and altitude on the Kerguelen Islands. Their profiles of free aromatic, aliphatic, and acetyl-conjugated amines were determined by HPLC. We related amine composition to species and environment using generalized discriminant analyses. • Key results: Amine composition differed significantly between species within the same environment, and the differences reflected phylogenetic positions. Moreover, across all species, amine metabolism differed between environments, and different lineages occupied different absolute positions in amine/environment space. Interestingly, all species had the same relative shifts in amine composition between environments. • Conclusion: Our results indicate a similar response of amine composition to abiotic environments in distantly related angiosperms, suggesting environmental flexibility of species is maintained despite major differences in amine composition among lineages. These results aid understanding of how in nature the plant metabolome integrates ecology and evolution, thus providing primordial information on adaptive mechanisms of plant metabolism to climate change

    Probing the cooperative nature of the conductive components in polystyrene/poly(3,4-ethylenedioxythiophene):Poly(styrene sulfonate)-single- walled carbon nanotube composites

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    The percolation threshold of single-walled carbon nanotubes (SWCNTs) introduced into polystyrene (PS) via a latex-based route has been reduced by using conductive surfactants. The use of the conductive polymeric latex, poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS), in conjunction with SWCNTs leads to conductive composites with loadings of both constituents below their own individual percolation thresholds. The high concentration of PEDOT:PSS in the final composites raises the concern that the composite conductivity is a result of the presence of the PEDOT:PSS alone. To elucidate the cooperative nature of the two conductive components, the contribution of the SWCNTs to the overall composite conductivity is investigated by replacing the original high-quality SWCNTs with SWCNTs of a lower quality. Percolation thresholds recorded for systems utilizing the lower quality tubes stabilized with nonconductive surfactants were over 2 wt % SWCNTs (4 times that of previously reported systems). The introduction of PEDOT:PSS was, once again, found to lower the percolation threshold (to 0.3 wt %) and to increase the ultimate conductivity up to the level of a pure PEDOT:PSS/PS blend. In the PS/PEDOT:PSS−SWCNT systems, the role of the SWCNT network is proposed to be limited to the formation of a template or scaffold on which a (more or less) continuous PEDOT:PSS layer deposits. The ultimate conductivity is therefore determined by the PEDOT:PSS alone

    Controlling electrical percolation in multicomponent carbon nanotube dispersions

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    Carbon nanotube reinforced polymeric composites can have favourable electrical properties, which make them useful for applications such as flat-panel displays and photovoltaic devices. However, using aqueous dispersions to fabricate composites with specific physical properties requires that the processing of the nanotube dispersion be understood and controlled while in the liquid phase. Here, using a combination of experiment and theory, we study the electrical percolation of carbon nanotubes introduced into a polymer matrix, and show that the percolation threshold can be substantially lowered by adding small quantities of a conductive polymer latex. Mixing colloidal particles of different sizes and shapes (in this case, spherical latex particles and rod-like nanotubes) introduces competing length scales that can strongly influence the formation of the system-spanning networks that are needed to produce electrically conductive composites. Interplay between the different species in the dispersions leads to synergetic or antagonistic percolation, depending on the ease of charge transport between the various conductive components

    Probing the cooperative nature of the conductive components in polystyrene/poly(3,4-ethylenedioxythiophene):Poly(styrene sulfonate)-single- walled carbon nanotube composites

    No full text
    The percolation threshold of single-walled carbon nanotubes (SWCNTs) introduced into polystyrene (PS) via a latex-based route has been reduced by using conductive surfactants. The use of the conductive polymeric latex, poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS), in conjunction with SWCNTs leads to conductive composites with loadings of both constituents below their own individual percolation thresholds. The high concentration of PEDOT:PSS in the final composites raises the concern that the composite conductivity is a result of the presence of the PEDOT:PSS alone. To elucidate the cooperative nature of the two conductive components, the contribution of the SWCNTs to the overall composite conductivity is investigated by replacing the original high-quality SWCNTs with SWCNTs of a lower quality. Percolation thresholds recorded for systems utilizing the lower quality tubes stabilized with nonconductive surfactants were over 2 wt % SWCNTs (4 times that of previously reported systems). The introduction of PEDOT:PSS was, once again, found to lower the percolation threshold (to 0.3 wt %) and to increase the ultimate conductivity up to the level of a pure PEDOT:PSS/PS blend. In the PS/PEDOT:PSS−SWCNT systems, the role of the SWCNT network is proposed to be limited to the formation of a template or scaffold on which a (more or less) continuous PEDOT:PSS layer deposits. The ultimate conductivity is therefore determined by the PEDOT:PSS alone
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