1,720,982 research outputs found

    Pathophysiology, clinics, diagnosis and treatment of heart involvement in carbon monoxide poisoning.

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    The toxicity of carbon monoxide has been recognized for long throughout history and is unquestionably the leading cause of unintentional poisoning deaths in the Western countries. The severity of poisoning is dependent upon environmental and human factor. The leading pathophysiological mechanism resides in the ability of carbon monoxide to bind to hemoglobin molecules with high affinity, displacing oxygen and generating carboxyhemoglobin, which is virtually ineffective to deliver oxygen to the tissues. The organs with the highest demand for oxygen such as the brain and the heart are more vulnerable to injury. Myocardial involvement is commonplace in moderate to severe carbon monoxide poisoning and is associated with a substantially higher risk of mortality. Besides hypoxic damage, carbon monoxide produces myocardium injuries with cardiospecific mechanisms, mostly attributable to direct damage at cellular or subcellular level. The clinical spectrum of heart involvement is broad and encompasses cardiomyopathy, angina attack, myocardial infarction, arrhythmias and heart failure up to myocardial stunning, cardiogenic shock and sudden death. Patients with underlying cardiac disease, especially coronary heart disease, are at greater risk of infarction and arrhythmias. Single photon emission computed tomography (SPECT) is the technique of choice for diagnosing cardiac involvement, whereas the recent introduction of the highly sensitive troponin immunoassays seems promising for the early triage of patients. No specific treatment other than oxygen delivery can be advocated for cardiac toxicity at present, and 100% oxygen therapy should be continued until the patient is asymptomatic and carboxyhemoglobin levels decrease below 5-10%. © 2012 The Canadian Society of Clinical Chemist

    D-dimer testing in the emergency department : consensus document of ACEMC, CISMEL, SIBioC and SIMeL

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    D-dimer testing is currently considered a cornerstone in the diagnostic approach of patients with suspected venous thromboembolism (VTE) across different health-care settings, including the emergency department (ED). Nevertheless, inappropriate or incorrect activities developing throughout the total testing process may substantially impair the clinical usefulness of this test and delay or even challenge the fast rule out or diagnosis of VTE. The leading problem of D-dimer is represented by the poor specificity for diagnosing VTE, wherein a minority of patients with a positive D-dimer are finally diagnosed with VTE, and even more importantly, the specificity further decreases with ageing, thus contributing to increase the overcrowding in short stay units such as the ED. Due to the large heterogeneity that characterizes the use of D-dimer in the emergency room, three Italian societies of laboratory medicine (Italian Committee for Standardization of Hematology and Laboratory Methods, Italian Society of Clinical Biochemistry and Molecular Biology, and Italian Society of Laboratory Medicine), along with the Academy of Emergency Medicine and Care, have developed a consensus document about the use of D-dimer testing for diagnostics of patients with suspected VTE in this health-care setting. The evidence-based indications contained in this document will cover the leading preanalytical, analytical, and postanalytical issues that may impair the clinical efficacy of D-dimer testing in the ED

    Going Beyond Counting First Authors in Author Co-citation Analysis

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    The present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed

    Variations on the Author

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    “Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship

    Appropriate Similarity Measures for Author Cocitation Analysis

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    We provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis

    Dispelling the Myths Behind First-author Citation Counts

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    We conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more sophisticated methods
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