1,721,099 research outputs found
Does the routine availability of CT–Derived FFR influence management of patients with stable chest pain compared to CT angiography alone? The FFRCT RIPCORD Study.
No full textOBJECTIVES: This study sought to determine the effect of adding computed tomography–derived fractional flow reserve (FFRCT) data to computed tomography angiographic (CTA) data alone for assessment of lesion severity and patient management in 200 patients with chest pain.BACKGROUND: Invasive and noninvasive tests used in the assessment of patients with angina all have disadvantages. The ideal screening test for patients presenting for the first time with chest pain would describe both coronary anatomy and the presence of ischemia and would be readily accessible, low cost, and noninvasive.METHODS: Two hundred patients with stable chest pain underwent CTA for clinical reasons, and FFRCT was calculated. Three experienced interventional cardiologists assessed the CTA result for each patient and by consensus developed a management plan (optimal medical therapy, percutaneous coronary intervention, coronary artery bypass graft surgery, or more information required). FFRCT data for each vessel were then revealed, and the interventional cardiologists made a second plan by consensus, using the same 4 options. The primary endpoint for the study was the difference between the 2 strategies.RESULTS: Overall, after disclosure of FFRCT data there was a change in the allocated management category on the basis of CTA alone in 72 cases (36%). This difference is explained by a discordance between the CTA- and FFRCT-derived assessments of lesion severity. For example, FFRCT was >0.80 in 13 of 44 vessels (29.5%) graded as having a stenosis>90%. In contrast, FFRCT was #0.80 in 17 of 366 vessels (4.6%) graded as having stenosis #50%.CONCLUSIONS: This study demonstrates proof of concept that the availability of FFRCT results has a substantial effect on the labeling of significant coronary artery disease and therefore on the management of patients compared to CTA alone. Further studies are needed to determine whether FFRCT has potential as a noninvasive diagnostic and management screening tool for patients with stable chest pain
Malignancy: an unrecognized risk factor for coronary stent thrombosis?
No full textStent thrombosis is a potentially catastrophic complication of coronary artery stenting. There have been particular concerns about the incidence of stent thrombosis following insertion of drug-eluting stents. We report a series of cases in which stent thrombosis occurred in association with malignancy and describe the potential mechanisms behind such an association. We speculate that this association merits further investigation as it raises the possibility that known malignancy may be a risk factor for stent thrombosis and that unexplained stent thrombosis, particularly if recurrent, should stimulate a search for occult malignanc
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
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
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe 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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