468 research outputs found

    The clinical effectiveness and cost-effectiveness of computed tomography screening for lung cancer : systematic reviews

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    Screening for lung cancer has been the subject of debate for the past three decades. This has largely stemmed from the results of chest X-ray screening studies where improvements in survival were obtained but without reductions in disease-specific, or total, mortality. The debate raises two issues: the design of studies to evaluate screening for lung cancer, in particular the choice of comparator; and the potential role of overdiagnosis of well-differentiated, slow-growing tumours that would not have led to symptoms or death in the lifetime of the affected patient. Lung cancer is the leading cause of death from cancer in the UK, killing approximately 34,000 people per year. By the time symptoms develop, the tumour is often at an advanced stage and the prognosis is bleak. Treatment at a less advanced stage of disease with surgical resection has been shown to substantially reduce mortality. Screening would be attractive if it could detect presymptomatic lung cancer at a stage when surgical intervention is feasible

    Mann and gender in Old English prose : a pilot study

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    It has long been known that OE mann was used in gender-neutral as well as gender-specific contexts. Because of the enormous volume of its attestations in Old English prose, the more precise usage patterns of mann remain, however, largely uncharted, and existing lexicographical tools provide only a basic picture. This article aims to present a preliminary study of the various uses of mann as attested in Old English prose, particularly in its surprisingly consistent use by an individual author, namely that of the ninth-century Old English Martyrology. Patterns emerging from this text are then tested against other prose material. Particular attention is paid to gender-specific usage, examples of which are shown to be exceptional for a word which largely occurs in gender-neutral contexts.Publisher PDFPeer reviewe

    Invited review : Selective use of antimicrobials in dairy cattle at drying-off

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    Administering intramammary antimicrobials to all mammary quarters of dairy cows at drying-off [i.e., blanket dry cow therapy (BDCT)] has been a mainstay of mastitis prevention and control. However, as udder health has considerably improved over recent decades with reductions in intramammary infection prevalence at drying-off and the introduction of teat sealants, BDCT may no longer be necessary on all dairy farms, thereby supporting antimicrobial stewardship efforts. This narrative review summarizes available literature regarding current dry cow therapy practices and associ-ated impacts of selective dry cow therapy (SDCT) on udder health, milk production, economics, antimicro-bial use, and antimicrobial resistance. Various methods to identify infections at drying-off that could benefit from antimicrobial treatment are described for select-ing cows or mammary quarters for treatment, includ-ing utilizing somatic cell count thresholds, pathogen identification, previous clinical mastitis history, or a combination of criteria. Selection methods may be enacted at the herd, cow, or quarter levels. Producers' and veterinarians' motivations for antimicrobial use are discussed. Based on review findings, SDCT can be ad-opted without negative consequences for udder health and milk production, and concurrent teat sealant use is recommended, especially in udder quarters receiving no intramammary antimicrobials. Furthermore, herd selection should be considered for SDCT implementa-tion in addition to cow or quarter selection, as BDCT may still be temporarily necessary in some herds for optimal mastitis control. Costs and benefits of SDCT vary among herds, whereas impacts on antimicrobial resistance remain unclear. In summary, SDCT is a vi-able management option for maintaining udder health and milk production while improving antimicrobial stewardship in the dairy industry.Peer reviewe

    Invited review : Selective use of antimicrobials in dairy cattle at drying-off

    Get PDF
    Administering intramammary antimicrobials to all mammary quarters of dairy cows at drying-off [i.e., blanket dry cow therapy (BDCT)] has been a mainstay of mastitis prevention and control. However, as udder health has considerably improved over recent decades with reductions in intramammary infection prevalence at drying-off and the introduction of teat sealants, BDCT may no longer be necessary on all dairy farms, thereby supporting antimicrobial stewardship efforts. This narrative review summarizes available literature regarding current dry cow therapy practices and associ-ated impacts of selective dry cow therapy (SDCT) on udder health, milk production, economics, antimicro-bial use, and antimicrobial resistance. Various methods to identify infections at drying-off that could benefit from antimicrobial treatment are described for select-ing cows or mammary quarters for treatment, includ-ing utilizing somatic cell count thresholds, pathogen identification, previous clinical mastitis history, or a combination of criteria. Selection methods may be enacted at the herd, cow, or quarter levels. Producers' and veterinarians' motivations for antimicrobial use are discussed. Based on review findings, SDCT can be ad-opted without negative consequences for udder health and milk production, and concurrent teat sealant use is recommended, especially in udder quarters receiving no intramammary antimicrobials. Furthermore, herd selection should be considered for SDCT implementa-tion in addition to cow or quarter selection, as BDCT may still be temporarily necessary in some herds for optimal mastitis control. Costs and benefits of SDCT vary among herds, whereas impacts on antimicrobial resistance remain unclear. In summary, SDCT is a vi-able management option for maintaining udder health and milk production while improving antimicrobial stewardship in the dairy industry.Peer reviewe

    Transformation, adaptation and development: relating concepts to practice

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    In recent years there has been a growing number of academic reviews discussing the theme of transformation and its association with adaptation to climate change. On the one hand this has stimulated exchange of ideas and perspectives on the parameters of transformation, but it has also given rise to confusion in terms of identifying what constitutes a non-incremental form of adaptation on the ground. What this article aims to do instead is help researchers and practitioners relate different interpretations of transformation to practice by proposing a typological framework for categorising forms of change that focuses on mechanisms and objectives. It then discusses how these categorisations link to the broader conceptions and critiques noted above, with the idea that this will enable those who seek to analyse or plan adaptation to better analyse what types of action are potentially constitutive of transformation. In doing so, it should equally assist in the identification and specification of critical questions that need to be asked of such activity in relation to issues of sustainability and equity. As the term transformation gains ground in discussions of climate change adaptation, it is necessary to take a step back, review quite what commentators mean when they use the word, and consider the implications on people, especially the most vulnerable and marginalised, of “doing” or promoting transformation in its different forms

    Context dependent learning in the serial RT task

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    This study investigated the development of contextual dependencies for sequential perceptual-motor learning on static features in the learning environment. In three experiments we assessed the effect of manipulating task irrelevant static context features in a serial reaction-time task. Experiment 1 demonstrated impaired performance after simultaneously changing display color, placeholder shape, and placeholder location. Experiment 2 showed that this effect was mainly caused by changing placeholder shape. Finally, Experiment 3 indicated that changing context affected both the application of sequence knowledge and the selection of individual responses. It is proposed either that incidental stimulus features are integrated with a global sequence representation, or that the changed context causes participants to strategically inhibit sequence skills

    Bestimmung der Bindung von Trijodthyronin an Serumproteine mittels Dextran-Gel-Filtration

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    1. Es wird eine Methode zur gleichzeitigen Bestimmung des sog. freien und des proteingebundenen Anteils von in vitro zugesetztem L-Trijodthyronin-131Jod im Serum mittels Dextran-Gel-Filtration angegeben. In der beschriebenen Form ist diese Technik für die routinemäßige Anwendung in der Klinik zur Bestimmung der Bindungs- und Transportverhältnisse von Trijodthyronin geeignet. 2. In sog. Verdrängungsversuchen wurde nichtmarkiertes Trijodthyronin dem Inkubationsgemisch von Serum und L-Trijodthyronin-131Jod zugesetzt. Die zugesetzten Trijodthyroninmengen erschöpfen die Gesamtbindungskapazität der Serumproteine in dem gewählten Konzentrationsbereich keineswegs. Im Gegensatz zum Verhalten der prozentualen Anteile des sog. freien und des proteingebundenen Trijodthyronins steigt die absolute Menge des proteingebundenen Trijodthyronins dabei steil an. Man findet eine Kurve, die nicht einer einfachen Sättigunskurve entspricht, sondern eine Resultante aus Sättigungskurven verschiedener Trijodthyronin-bindender Proteine und Verdrängungskurven kompetitiv gebundener Substanzen (z.B. Thyroxin) darstellt. 3. Dextran-Gel wirkt nicht als einfaches Molekülsieb für Trijodthyronin. Es greift vielmehr durch Adsorptionsvorgänge kompetitiv in die Serumproteinbindungsverhältnisse des Trijodthyronins ein. Die physiologische Bedeutung des sog. freien Anteils an Trijodthyronin wird diskutiert. 4. Die Methode zur Bestimmung des proteingebundenen Jods (PB127I) mittels alkalischer offener Veraschung (Barker) wurde technisch vereinfacht und bezüglich ihrer Reproduzierbarkeit untersucht. Die131Jodausbeute aus zugesetztem L-Thyroxin-131Jod lag bei diesem Verfahren bei ca. 80%

    How to do an evaluation: pitfalls and traps

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    The recent literature is replete with papers evaluating computational tools (often those operating on 3D structures) for their performance in a certain set of tasks. Most commonly these papers compare a number of docking tools for their performance in cognate re-docking (pose prediction) and/or virtual screening. Related papers have been published on ligand-based tools: pose prediction by conformer generators and virtual screening using a variety of ligand-based approaches. The reliability of these comparisons is critically affected by a number of factors usually ignored by the authors, including bias in the datasets used in virtual screening, the metrics used to assess performance in virtual screening and pose prediction and errors in crystal structures used
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