1,720,958 research outputs found
A pitfall in echographic diagnosis of abdominal aortic aneurysm: when para-aortic lymph nodes are the trick
No full text: The abdominal aortic aneurysm (AAA) is a potentially fatal asymptomatic disease. They progress silently with clinical complications that, when they occur, constitute a very serious event, frequently resulting in the patient's exitus. As a result, early detection and treatment are critical, because the right therapeutic strategy can halt the disease's natural progression. AAA is frequently discovered as an incidental finding during an abdominal ultrasound or a plain X-ray of the abdomen, which is required for other pathologies. The primary diagnostic tool for AAA identification is abdominal B-mode ultrasound. It is cheap, widely available, non-invasive, and has a high diagnostic sensitivity. However, this diagnostic tool may fail in rare cases due to misleading anatomical findings. We present an unusual flaw in echographic AAA evaluation that should be considered during the diagnostic work-up
Transient global amnesia in a patient with painless spontaneous internal carotid artery dissection: An unusual but possible underlying cause
No full textThe overall echogenicity (GSM) of carotid intima-media complex shows a positive correlation with arterial stiffness in hypertensive patients
No full textBackground: Arterial stiffness measurement still plays a role in prediction of future cardiovascular events, thus helping for quantification of patients' cardiovascular (CV) risk level. However, significant measurement difficulties still exist, making its widespread evaluation not routinary. At present indices of arterial stiffness have not been associated with qualitative morphological characteristics of intima-media complex. The intima-media thickness (IMT) measurement is no longer recommended in the cardiovascular disease (CVD) risk assessment due to lack of a standard acquisition protocol. The intima media gray scale median (IM-GSM) is a relatively simple measurement, acquirable during a conventional carotid color-Doppler ultrasound examination. This study aims at investigating the possible relationship between arterial stiffness and echogenicity of IM-GSM of the common carotid arteries, in patients already diagnosed with arterial hypertension.Material and methods: A total of 421 hypertensive patients were retrospectively selected from our database of hypertension outpatients ambulatory. They were divided into two groups according to IM-GSM values (cutoff value: 30) and then subsequently compared.Results: In our study population, subjects with IM-GSM > 30 showed a statistically increased arterial stiffness and left ventricle mass index. A weak positive correlation was also found between IM-GSM, systolic blood pressure and duration of hypertension.Conclusion: The data presented here indicated that the variation of arterial stiffness observed in hypertensive patients is associated with structural modifications in carotid arterial wall
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
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