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Spontaneous coronary artery dissection: A neglected cause of acute myocardial ischaemia and sudden death
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Persistent increase of sympathetic tone is associated with angiographic no-reflow phenomenon.
No full textChanges in autonomic nervous system activity: spontaneous versus balloon induced myocardial ischaemia
No full textAims Cardio-cardiac reflexes may be evoked by both myocardial ischaemia and coronary occlusion itself. The aim of the study was to assess the intrapatient behaviour of autonomic nervous system balance during spontaneous and balloon-induced coronary ischaemia.
Methods and results We studied a group of patients admitted to the coronary care unit for acute coronary syndrome without ST-segment elevation who experienced spontaneous episodes of myocardial ischaemia during bed rest and ECG monitoring. The inclusion criterion was 80-90% lumen stenosis, amenable to angioplasty. Balloon coronary occlusion was performed at 4-6 atmospheres for 120 s. Autonomic nervous system activity was assessed by heart rate variability (HRV) analysis in frequency domain. We analysed 14 episodes of spontaneous ischaemia and 14 episodes of balloon coronary occlusion. During spontaneous ischaemia, HRV showed an increase in the low/high frequencies ratio (11.8 +/- 5.7), as compared to 5 min before and 5 min after (4.4 +/- 2.7 and 3.9 +/- 1.8, respectively) (p = 0.001). The opposite occurred during balloon coronary occlusion (0.8 +/- 0.4 vs. 3.9 +/- 2.0 and 5.1 +/- 2.1, respectively; p = 0.001).
Conclusions Balloon inflation and occlusion evokes baroreceptor vagal predominance in response to a stretch stimulus of the coronary artery. Conversely, spontaneous occlusion during unstable angina is accompanied by naturally occurring sympathetic activation. Sympathetic activation may have a role in the natural history of the disease
Effect of Pravastatin on myocardial perfusion after percutaneous transluminal coronary angioplasty
No full textWe studied the effect of pravastatin on coronary perfusion after percutaneous, transluminal coronary angioplasty. An exercise test performed within 2 weeks after percutaneous transluminal coronary angioplasty induced reversible perfusion defects in 66% of patients taking pravastatin and 64% of those taking placebo. At follow-up, the exercise test still induced reversible perfusion defects in 3% of patients taking pravastatin and 29% of those taking placebo
Endothelial function predicts future development of coronary artery disease: a study of women with chest pain and normal coronary angiograms.
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Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe 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
Get PDF“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
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