1,721,080 research outputs found
[Hypertensive nephrosclerosis: an exhaustive diagnosis?].
No full textHypertensive nephrosclerosis is a much overused clinical diagnosis, largely unsubstantiated by biopsy data. It is in fact a clinical-pathological diagnosis implying a causal role of hypertension in the associated chronic kidney disease. However, such a simple, linear causality is often not obvious or easy to demonstrate. Further factors like age, Afro-American descent, genetic and immunological factors as well as dysmetabolic syndrome may contribute to the development and progression of arterionephrosclerosis independently of hypertension
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
Long-term effects of moderate protein diet on renal function and low-grade inflammation in older adults with type 2 diabetes and chronic kidney disease
No full textAppropriate 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
Quantitative chest tomography indexes are related to disease activity in systemic sclerosis: results from a cross-sectional study
No full textObjective The aim of this study is to verify if there are correlations between quantitative chest tomography (QCT) indexes and disease activity (DA) in a cohort of patients with systemic sclerosis (SSc). Methods SSc patients were assessed for DA and underwent high resolution chest tomography (CT). CT images were analysed with an operator-independent algorithm extracting the QCT indexes. DA assessment was conducted according to the EUSTAR index, where a score ≥2.5 indicates high DA (hDA). Correlations between clinical data and QCT indexes were investigated with the Spearman's test. The Mann-Whitney test assessed the distribution of the QCT indexes among the groups. Receiver operating characteristics (ROC) curve and linear regression analysis were conducted in order to identify the best cut-off value and contribution for each QCT index in assessing hDA in SSc patients. Results Sixty patients (52 females, mean age 53.2 years, mean disease duration 5.3 years) were enrolled. A significant difference was found in QCT indexes distribution between patients with hDA and those with low DA. A mild strength correlation between QCT indexes and DA was observed. Once performed ROC curves and linear regression, Skewness on parenchymal lung <1.85 gave a significant contribution to the model in identifying subjects with hDA (p<0.001), showing sensitivity 79.5%, specificity 68.7%, and accuracy 76.6%. Conclusion QCT indexes correlate with SSc DA. These data introduce new possibilities for QCT application in clinical practice, especially in patient's follow-up. Moreover, QCT could be implemented in a new SSc DA score based on operator- independent parameters
New intrarenal echo-doppler velocimetric indices for the diagnosis of renal artery stenosis.
No full textWe aimed at comparing the positive and negative predictive
values (PPV, NPV) of several intrarenal velocimetric indices
for revealing the presence of renal artery stenosis (RAS)
among hypertensive patients who underwent a renal
angiography for the clinical suspicion of renovascular
hypertension. In 106 patients (200 kidneys), the pulsatility
index (PI) and resistive index (RI), the acceleration time (AT),
and the mean systolic acceleration (ACCsys) were evaluated.
In addition, the maximal systolic acceleration (ACCmax), that
is, the maximal slope of the acceleration phase, and the
maximal acceleration index (AImax), that is, the ratio between
ACCmax and the relative peak systolic velocity, were
calculated. On angiography, we found that 56 (28%) of the
200 arteries had a greater than 60% RAS. PI and RI had an
NPV below 75%, whereas AT, ACCsys, ACCmax, and AImax had
an NPV always above 95%. However, ACCmax, and AImax, at
their best cutoff limits, had higher PPV than ACCsys and AT
(60 and 70% vs 45 and 51%, respectively). Thus, in a cohort of
patients with a high prevalence of RAS, PI and RI failed to
reach an NPV adequate for a screening test. In contrast, all
the acceleration indices we tested had a sufficiently high NPV
but AImax appears superior to the others because of higher
PPV. We propose the evaluation of AImax as an additional
screening test in patients with hypertension and the clinical
suspicion of RAS
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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