1,720,959 research outputs found
The angle of the components of the common atrioventricular valve predicts the outcome of surgical correction in patients with atrioventricular septal defect and common atrioventricular junction
No full textBackground: Three-dimensional echocardiography offers new insights into valvar function in atrioventricular septal defects (AVSDs). The aim of this study was to identify a morphological marker to predict the functional outcomes of left atrioventricular valves (AVVs) following the repair of AVSDs.Methods: Twenty-nine consecutive patients were evaluated preoperatively using 2-dimensional and 3-dimensional echocardiography. The angle of the AVV relative to the crux of the heart was measured in multiplanar review mode.Results: The severity of postoperative left AVV regurgitation was correlated with preoperative valvar angle, being more acute in patients with moderate or severe regurgitation (mean, 57 ± 13° vs 83 ± 9° in patients with no or mild regurgitation; P = .002). Angles ? 59° predicted severe regurgitation with 79% specificity.Conclusions: Multiplanar review of 3-dimensional data sets is valuable for the assessment of the functional morphology of AVSD valves. Using this technique, more acute AVV angles predicted increased likelihood of severe regurgitation following surgical repair.<br/
Leukodepletion reduces renal injury in coronary revascularization: a prospective randomized study
No full textBackground: cardiopulmonary bypass (CPB) is an important contributor to renal failure, which is a well-recognized complication after coronary artery bypass grafting (CABG). Leukodepletion reduces CPB-associated inflammation and resultant end-organ injuries. However, its effectiveness in renal protection has not been evaluated in a prospective randomized clinical setting.Methods: forty low-risk patients awaiting elective CABG with normal preoperative cardiac and renal function were prospectively randomized into those undergoing nonpulsatile CPB without (group A: N = 20) and with leukodepletion (group B: N = 20). Renal glomerular and tubular injury were assessed by urinary excretion of microalbumin and retinol binding protein (RBP) indexed to creatinine (Cr), respectively. Daily measurements were taken from admission to postoperative day 5. Fluid balance, serum creatinine, and blood urea were also monitored.Results: no mortality or renal complication occurred. Both groups had similar demographic makeups, Parsonnet scores, extents of coronary revascularization and, durations of CPB and aortic cross-clamping. Daily fluid balance, serum creatinine, and blood urea remained comparable in both groups throughout the study period. From equal preoperative values, a significantly higher release of urinary RBP:Cr (7,807 ± 2,227 vs 3,942 ± 2,528; p < 0.001) and urinary microalbumin:Cr (59.4 ± 38.0 vs 4.7 ± 6.7; p < 0.0001) occurred in group A, peaking on day 1 before returning to approximate baseline levels.Conclusions: although clinically overt renal complications were absent, sensitive indicators revealed significantly more injury to both renal tubules and glomeruli after nonpulsatile CPB without leukodepletion. These data suggest that leukocytes play an important role in post-CPB renal dysfunction, and leukodepletion may offer some renal protection in low-risk patients during CABG
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
Autotransfusion decreases blood usage following cardiac surgery - a prospective randomized trial
No full textIntroduction: 10% of blood issued by the National Blood Service (220 000) is utilised in cardiac procedures. Transfusion reactions, infection risk and cost should stimulate us to decrease this transfusion rate. We tested the efficacy of autotransfusion of washed postoperative mediastinal fluid in a prospective randomized trial.Patients and methods: 166 patients undergoing coronary artery bypass grafting (CABG), valve or CABG+valve procedures were randomized into three groups. The indication for transfusion was a postoperative haemoglobin (Hb) <10g/l or a packed cell volume (PCV) <30. When applicable, group A patients received washed post-operative drainage fluid. Group B all received blood processed from the cardiopulmonary bypass (CPB) circuit following separation from CPB and if appropriate washed post-operative drainage fluid. Group C were controls. Groups were compared using analysis of variance.Results: There was no significant difference in age, sex, type of operation, CPB time and preoperative Hb and PCV between the groups. Blood requirements were as shown.
[see table 3 in main text]Twelve patients in group A and 10 in group B did not require a homologous transfusion following processing of the mediastinal drainage fluid.Conclusion: Autotransfusion of washed postoperative mediastinal fluid can decrease the amount of homologous blood transfused following cardiac surgery. There was no demonstrable benefit in processing blood from the CPB circuit as well as mediastinal drainage fluid
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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