1,721,053 research outputs found
Hemolysis after percutaneous paravalvular leak repair
No full textParavalvular leak is a common complication after surgical mitral valve replacement. Surgically implanted prosthetic valves are complicated with paravalvular leaks in 17%.(1) Surgical closure of paravalvular leaks is the most common therapy for these defects. Percutaneous closure is an alternative to repeat surgery for a selected high-risk population. We present a case of a patient who developed severe haemolytic anaemia and secondary renal failure after partially successful percutaneous closure of paravalvular leakage of a prosthetic mitral valve. The assumption is that the combination of a metallic foreign body and high shear stress caused haemolysis by damaging red blood cells
Dual antiplatelet therapy after percutaneous left atrial appendage occlusion: single center experience with the Amplatzer Cardiac Plug
No full textBackground: Percutaneous left atrial appendage occlusion (LAAO) is an alternative to anticoagulation in atrial fibrillation patients at high bleeding risk. Dual antiplatelet therapy (DAPT) is generally recommended in the months following the procedure to prevent thrombotic complications. The aim of this study was to evaluate the safety and efficacy of DAPT after LAAO in a single-centre population of high bleeding risk patients. Methods: All patients who received DAPT after LAAO using the Amplatzer Cardiac Plug at Jessa Hospital (Hasselt, BE) between February 2011 and October 2016 were included. Patient characteristics, procedural outcome and clinical events (bleeding, stroke and adverse events) were prospectively followed. Changes in antithrombotic and/or anticoagulant regimens were assessed. Results: Thirty-nine patients (77 +/- 7 years, 51% male, CHA(2)DS(2)-VASc 5(3-6), Hypertension, Abnormal Renal/Liver Function, Stroke, Bleeding History or Predisposition, Labile INR, Elderly, Drugs/Alcohol Concomitantly (HAS-BLED) 3(3-4)) were included. An initial strategy of one month DAPT (n = 2) was changed to six months DAPT (n = 37) after one thrombotic complication (device thrombosis) at 4.5 months. Post-procedural DAPT duration was 6.1 +/- 3.7 months, after which aspirin mono-therapy (62%), no antiplatelet/anticoagulant therapy (15%) or a tailored antithrombotic regimen was maintained. At mean follow-up of 21 +/- 13 months, seven patients had died (18%), no strokes had occurred (0%) and nine bleedings of which four were major (10%). All major bleedings occurred within the first six months after the procedure during DAPT. Conclusion: Antithrombotic therapy after percutaneous LAAO is needed to prevent thrombotic complications, yet these impose bleeding complications in this high-risk population. Further efforts are needed to define the optimal duration of DAPT, aimed at reducing bleeding complications while maintaining a low thrombosis rate
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe 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
Full text link“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
Full text linkWe 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
Characterizing Pathophysiological Patterns of Coronary Artery Disease Among Individuals With Elevated Lipoprotein(a)
No full textDispelling the Myths Behind First-author Citation Counts
Full text linkWe 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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