1,720,976 research outputs found
Prevention of contrast-induced nephropathy: a single center randomized study
No full textBackground: Contrast-induced nephropathy (CIN) is the third cause of acute deterioration of renal function in hospitalized patients. Hypothesis: The purpose of the study was to compare the efficacy of saline infusion, saline infusion plus N-acetylcysteine (NAC), and sodiumbicarbonate (SB) infusion to prevent CIN in patients undergoing coronary angiography and/or percutaneous coronary intervention. Methods: We prospectively studied 156 patients with a baseline creatinine level ≥1.2mg/dL. The primary endpoint was the development of CIN, defined as an increase in serum creatinine concentration ≥25% over the baseline value within 5 days fromcontrast exposure. Results: Contrast-induced nephropathy developed in 23 patients (14.7%). Incidence of the primary endpoint was similar in the 3 groups of treatment, occurring in 7 patients (14%) in the saline infusion group, in 9 (17%) in the saline infusion plus NAC group, and in 7 (14%) in the SB infusion group. Conclusions: Our findings suggest that neither the addition of NAC nor the administration of SB add further benefit in CIN prevention, compared to standard hydration with isotonic saline infusion
Troponin I Levels in Asymptomatic Hemodialysis Patients
No full textBACKGROUND:
End-stage renal disease (ESRD) represents a situation in which persistently elevated levels of cardiac troponins I (cTnI) are frequently found in the absence of clinically evident cardiac disease. Moreover, the effect of hemodialysis (HD) on cTnI levels is not definitively elucidated. The aim of this study was to investigate the effects of HD on cTnI levels in ESRD patients.
METHODS:
We enrolled 30 asymptomatic ESRD patients on maintenance HD. All the patients were dialyzed thrice weekly. We compared each other's cTnI levels obtained before HD sessions (pre-HD) and cTnI levels obtained before and after HD sessions (post-HD).
RESULTS:
The median value of baseline cTnI, measured before the first dialysis session of the week, was 0.018 ng/mL (interquartile range 0.012-0.051) and elevated levels (>0.034 ng/mL) were found in 9 (30%) patients. Pre-HD cTnI levels showed a statistically significant decrease between the first and the second weekly HD sessions (from 0.018 to 0.016 ng/mL; p = 0.002), while no difference was observed between the second and the third sessions over the week. Finally, no statistically significant differences were found between pre-HD and post-HD cTnI levels, considering each HD session and the averaged cTnI values.
CONCLUSIONS:
Our results indicate that HD does not significantly affect cTnI levels. Even when statistically significant, the observed changes were without clinical relevance indicating that HD does not affect by itself the diagnostic accuracy of cTnI assay in ESRD patients
Intracoronary epinephrine for contrast-medium-induced microvascular obstruction in a chronically hemodialyzed patient
No full textCoronary angiography and computed tomography angiography in the diagnosis of extrinsic compression of left internal mammary artery
No full text
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
- …
