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    Combination use of an automatic anti-tachycardia pacemaker and an automatic implantable cardioverter-defibrillator in sustained recurrent ventricular tachycardia resistant to drugs

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    We used the combination of an antitachycardia automatic ventricular pacemaker with the automatic implantable cardioverter-defibrillator in two patients with sustained, recurrent, drug-resistant ventricular tachycardias in whom a surgical ablation was not indicated. The indications for the combined use of the two systems were the possibility to control: a) the ventricular tachycardias with ventricular programmed stimulation; b) the arrhythmias which might eventually degenerate into ventricular flutter or fibrillation (as a result of anti-tachycardia pacing) with the defibrillator. To avoid any possible interference between the two systems we used the following protocol: a) endocardial bipolar pacing; b) the sensing electrodes of the defibrillator were placed as far as possible from the endocardial one; c) a suitable programming of the pacemaker output; d) a careful selection of the anti-tachycardia pacing programme (burst rate inferior to the cut-off rate of the cardioverter-defibrillator and/or a duration of the burst pacing inferior to the arrhythmia sensing time of the defibrillator); e) use of cardioverter-defibrillators with a high cut-off rate. We never observed, during the follow-up (11 and 4 months, respectively), interference between the two systems. Both patients had ventricular tachycardia recurrences (51 and 3 episodes, respectively). The arrhythmias were correctly detected and interrupted by the pacemaker without the intervention of the defibrillator. These data confirm the feasibility of the combined use of the two systems in patients with ventricular tachycardias and, in selected cases, this approach is preferable. The anti-tachycardia pacemaker counteracts some limitations of the defibrillators available at present. It offers a protection against bradyarrhythmias and allows a more precise storage of arrhythmic events. The anti-tachycardia pacemaker often controls ventricular tachycardias without the intervention of the defibrillator, thus giving the same a longer life-span and allowing patients to avoid the shock

    [Acute myocardial infarction in a 13-year-old boy with Duchenne's disease].

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    A 13-year-old boy with Duchenne's muscular dystrophy suffered an acute myocardial infarction as shown by typical electrocardiographic and enzyme changes, and by the results of radionuclide studies. this is the third reported case of the acute myocardial infarction in a patient with Duchenne's muscular dystrophy

    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
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