1,721,007 research outputs found
PROPHYLAXIS OF CYTOMEGALOVIRUS (CMV) DISEASE IN SOLID ORGAN TRANSPLANT RECIPIENTS: A SYSTEMATIC REVIEW
No full textPRE-EMPTIVE TREATMENT FOR CYTOMEGALOVIRUS VIRAEMIA TO PREVENT CYTOMEGALOVIRUS DISEASE IN SOLID ORGAN TRANSPLANT RECIPIENTS - A SYSTEMATIC REVIEW OF RANDOMISED CONTROLLED TRIALS
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
Antiviral medications for preventing cytomegalovirus disease in solid organ transplant recipients
No full textBackground
The risk of cytomegalovirus (CMV) infection in solid organ transplant recipients has resulted in the frequent use of prophylaxis with the aim of preventing the clinical syndrome associated with CMV infection.
Objectives
To determine the benefits and harms of antiviral medications to prevent CMV disease and all-cause mortality in solid organ transplant recipients.
Search strategy
We searched the Cochrane Central Register of Controlled Trials, MEDLINE, EMBASE, reference lists and abstracts from conference proceedings without language restriction.
Date of last search : February 2007
Selection criteria
Randomised controlled trials (RCTs) and quasi-RCTs comparing antiviral medications with placebo or no treatment, comparing different antiviral medications and comparing different regimens of the same antiviral medications in recipients of any solid organ transplant.
Data collection and analysis
Statistical analyses were performed using the random effects model and results expressed as relative risk (RR) for dichotomous outcomes with 95% confidence intervals (CI). Subgroup analysis and univariate meta-regression were performed using restricted maximuml-ikelihood to estimate the between study variance. Multivariate meta-regression was performed to investigate whether the results were altered after allowing for differences in drugs used, organ transplanted and recipient CMV serostatus at the time of transplantation.
Main results
Thirty four studies (3850 participants) were identified. Prophylaxis with aciclovir, ganciclovir or valaciclovir compared with placebo or no treatment significantly reduced the risk for CMV disease (19 studies; RR 0.42, 95% CI 0.34 to 0.52), CMV infection (17 studies; RR 0.61, 95% CI 0.48 to 0.77), and all-cause mortality (17 studies; RR 0.63, 95% CI 0.43 to 0.92) primarily due to reduced mortality from CMV disease (7 studies; RR 0.26, 95% CI 0.08 to 0.78). Prophylaxis reduced the risk of herpes simplex and herpes zoster disease, bacterial and protozoal infections but not fungal infection, acute rejection or graft loss. Meta-regression showed no significant difference in the relative benefit of treatment (risk of CMV disease or all-cause mortality) by organ transplanted or CMV serostatus; no conclusions were possible for CMV negative recipients of negative organs. In direct comparison studies, ganciclovir was more effective than aciclovir in preventing CMV disease (7 studies; RR 0.37, 95% CI 0.23 to 0.60). Valganciclovir and IV ganciclovir were as effective as oral ganciclovir.
Authors' conclusions
Prophylaxis with antiviral medications reduces CMV disease and CMV-associated mortality in solid organ transplant recipients. They should be used routinely in CMV positive recipients and in CMV negative recipients of CMV positive organ transplants.
Keywords
KeyWords Plus:HIGH-DOSE ACYCLOVIR; RANDOMIZED CONTROLLED-TRIAL; PREEMPTIVE GANCICLOVIR THERAPY; RENAL-ALLOGRAFT REJECTION; PLACEBO-CONTROLLED TRIAL; INTRAVENOUS IMMUNE GLOBULIN; LONG-TERM PROPHYLAXIS; VS. ORAL GANCICLOVIR; LIVER-TRANSPLANTATION; HEART-TRANSPLANTATIO
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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