1,720,966 research outputs found
Endothelial dysfunction: Its clinical value and methods of assessment
No full textEndothelial dysfunction (ED) is a systemic disorder characterized by reduced production of nitric oxide. This pathologic condition, which impairs vascular homeostasis, leads to the loss of protective properties of endothelial cells and is related to the pathogenesis of cardiovascular diseases. ED may affect every vascular bed, accounting for several clinical implications, particularly when the coronary bed is affected. Although the reliability of ED as a cardiovascular disease surrogate is still debated, many methods for its assessment have been proposed. In this review, we underline the clinical value of ED in the cardiovascular field and summarize the principal methods currently available for its assessment. © Springer Science+Business Media 2014
Long-term clinical outcomes following sirolimus-eluting stent implantation in patients with acute myocardial infarction. A meta-analysis of randomized trials
No full textObjectives The aim of this study was to perform a metaanalysis of randomized trials, evaluating the long-term outcomes of sirolimus-eluting stents (SES) versus baremetal stents (BMS) in patients with ST-segment elevation myocardial infarction (STEMI). Background Despite short-term outcomes of patients with STEMI undergoing primary percutaneous coronary intervention indicate a benefit of SES in terms of reintervention, several concerns remain on the long-term safety and efficacy of SES. Methods A systematic literature search of electronic resources, through October 2011, was performed using specific search terms. Included trials were randomized studies comparing SES to BMS in STEMI patients, with a follow-up C3 years. Results Seven trials were included, with a total of 2,364 patients. At a median follow-up of 3 years, SES significantly reduced the risk of target-vessel revascularization when compared with BMS [odds ratio (OR), 0.44; 95 % confidence interval (CI), 0.34-0.57; p<0.0001], without increasing the risk of mortality (OR 0.78; 95 % CI, 0.57-1.08; p = 0.14), reinfarction (OR 0.91; 95 % CI, 0.61-1.35, p = 0.64) and early to late stent thrombosis (OR 0.77; 95 % CI, 0.49-1.20; p = 0.25). However after the first year, SES did not further reduce target-vessel revascularization (OR 1.06; 95 % CI, 0.64-1.74; p = 0.83) and increased the risk of very late stent thrombosis (OR 2.81; 95 % CI, 1.33-5.92; p = 0.007). Conclusions At long-term follow-up, SES compared to BMS use in STEMI patients reduces the risk of targetvessel revascularization, without increasing the risk of death and reinfarction. However, the strong SES efficacy is counterbalanced by a significant risk of very late stent thrombosis. © Springer-Verlag 2012
Abluminal-Coated Drug-Eluting Bifurcation-Dedicated Stent for the Treatment of Tibioperoneal Bifurcation
No full textEndovascular treatment of below-the-knee region disease is often challenging because of the involvement of arterial bifurcations. Several cases have been reported on the use of coronary stents for the treatment of these patients, but limited evidence is available on the use of dedicated coronary bifurcation devices. We here report the endovascular treatment of a symptomatic bifurcation lesion in below-the-knee region, using a self-expanding Biolimus A9-eluting stent in combination with a "conventional" coronary drug-eluting stent
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
Pharmacotherapeutic considerations for the use of prasugrel and ticagrelor to reduce stent thrombosis in patients with acute coronary syndrome
No full textDespite the improvement in stent technology, stent thrombosis (ST), a potentially catastrophic event, still occurs. Among several risk factors for ST, high on-treatment platelet reactivity to clopidogrel has been demonstrated to play a role, occurring in about one-third of the patients. In order to overcome this limitation, prasugrel and ticagrelor, newer P2Y12 inhibitors, have been developed and approved for clinical use. Two large clinical trials, TRial to assess Improvement in Therapeutic Outcomes by optimizing platelet inhibitioN with prasugrel-thrombolysis in myocardial infarction (TRITON-TIMI) 38 and Study of Platelet Inhibition and Patient Outcomes (PLATO), evaluated these drugs in patients with acute coronary syndrome (ACS), showing a significant improvement in efficacy end points (including a prominent reduction in ST occurrence) compared to clopidogrel. In contrast, the TRILOGY ACS trial found no benefit with prasugrel compared to clopidogrel in patients with medically treated ACS. The aim of this review is to consider decision-making strategies between prasugrel and ticagrelor in daily clinical practice. © The Author(s) 2012
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
Dispelling 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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