1,720,976 research outputs found

    Omega-3 in antiarrhytmic therapy: cons position

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    The association between omega-3 (n-3 polyunsaturated fatty acids) and the clinical outcome of patients with cardiovascular diseases such as coronary heart disease is currently unclear, especially regarding its possible antiarrhythmic effects and the not quite understood mechanisms of action. In the last 15 years, several epidemiological studies have shown a lower incidence of sudden cardiac death with a diet rich in omega-3 or fish consumption. The antiarrhythmic properties related to omega-3 have been related to modulation of sodium-dependent ion channels or sodium-calcium exchangers of myocytes through a reduction of their excitability especially in ischaemic or damaged myocardial tissue. However, the results of experimental studies have not always been consistent. Although the role of omega-3 in preventing sudden cardiac death has been evaluated in several clinical trials that included patients with coronary artery disease (particularly in patients with post-myocardial infarction), the interpretation of such data must be treated with extreme caution. In particular, while a reduction in cardiac death was demonstrated by a meta-analysis of several randomized clinical trials, a reduced risk of sudden cardiac death has been described only in the GISSI-Prevenzione study, while in other studies the evidence that emerged is more controversial, with wide confidence intervals that support the possibility of heterogeneity in the distribution of the factors involved in the efficacy of treatment. Omega-3 is probably involved in the prevention of cardiovascular mortality through different mechanisms, and it is crucial to study its association with other drugs such as ACE inhibitors or calcium channel blockers. The study of antiarrhythmic drugs has been divided into prevention of supraventricular and ventricular arrhythmias. In these conditions, the role of omega-3 seems to be more pronounced in atrial tachyarrhythmias such as atrial fibrillation, but does not have a role in ventricular arrhythmias. In summary, the antiarrhythmic effect of omega-3 is not clearly evident and further studies are needed to investigate its beneficial effect in cardiac mortality compared with arrhythmic death

    Evolving concept of cardioprotection in myocardial infarction: from SMILE-1 to SMILE-5.

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    The renin–angiotensin–aldosterone system (RAAS) is a central regulator of cardiovascular (CV) and renal function and plays a key role in the pathophysiology of various CV and renal diseases. Clinical data has demonstrated that ACE inhibitors are very effective at reducing blood pressure in a large proportion of patients with hypertension (HBP), when given alone or in combination. ACE inhibitors improve the clinical prognosis of patients with congestive heart failure (CHF) and AMI, particularly when complicated by overt left ventricular (LV) dysfunction, although their efficacy maybe limited in postmyocardial patients with preserved LV function. Among the different ACE inhibitors, the efficacy of zofenopril has been proven in a wide population of patient and in the different studies. The SMILE project was a large clinical programme aimed at investigating the efficacy of zofenopril for the treatment of patients with AMs with HBP and coronary heart disease, in particular AMI

    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

    Author Index

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    koamabayili/VECTRON-author-checklist: VECTRON author checklist

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    We have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
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