1,720,968 research outputs found
The Scimitar Syndrome: An European Multicentric Study
No full textBackground: Scimitar syndrome is a rare congenital heart disease. In order to evaluate the surgical results of managing this malformation, we have embarked on a multi-centric European study involving 19 different Centres and reporting the widest so far published series in the medical literature.
Methods: From January 1997 to December 2007, 68 patients with scimitar syndrome who underwent surgical correction, were included. Primary outcomes include hospital mortality and the efficacy of repair at the follow-up.
Results: Median age was 1.32 years (IQR 0.28 –7.87). Forty-two patients (62%) presented with symptoms including upper respiratory tract infections (n=25), cardiac failure (n=24), recurrent pneumonia (n=9), and cyanosis (n=4). Surgical repair included: intra-atrial baffle technique in 38 patients (56%)(group 1), re-implantation of the "scimitar vein" onto left atrium in 21 patients (31%)(group 2). Nine patients (13%) underwent a right pneumectomy together with atrial septal defect closure (group 3). Four patients died in hospital (5.9%)(1 in group 1, 2.6% and 3 in group 3, 33%)(p=0.008). Postoperative complications were more frequently reported in group 3 (7/9, 78%)(p=0.02, group 3 vs. all) if compared to group 2 (14/21, 67%) and group 1 (14/38, 37%)(p=0.02, group 2 vs. group
and related to the presence of preoperative congestive heart failure (OR=13). Median follow-up time was 4.5 year (IQR 1.6 – 8.3). Nine of 58 patients who survived the corrective procedure (15.5%) showed a stenosis of the scimitar drainage (6/37 in group 1, 16% and 3/21, 14.3% in group
Four patients (7%) required a reoperation, all in group 1; three patients (5.3%) required balloon dilation/stenting for scimitar vein stenosis (2 in group 1, 6% and 1 in group 2, 4.8%).
There were 2 late deaths (3.1%) due to severe pulmonary arterial hypertension (1 in group 1, 2.7% and 1 in group 2, 4.7%).
Conclusions: Surgical repair of scimitar syndrome is safe and effective, however, a relatively high incidence of stenosis of the scimitar venous drainage is present at follow-up. The intra-atrial baffle technique carries a lower incidence of postoperative complications, but it seems to relates to a higher incidence of reoperations for scimitar vein stenosis
The Effect of Vacuum on Venous Drainage: an Experimental Evaluation on Pediatric Venous Cannulas and Tubing Systems
No full textIntroduction: To observe how vacuum assisted venous drainage (VAVD) may influence the flow in a cardiopulmonary bypass circuit with different size of venous lines and cannulas.
Methods: The experimental circuit was assembled to represent the cardiopulmonary bypass circuit routinely used during cardiac surgery. Wall suction was applied directly, modulated and measured into the venous reservoir. The blood flow was measured with a flow-meter positioned on the venous line. The circuit prime volume was replaced with group O date expired re-suspended red cells and Plasmalyte 148 to a hematocrit of 28% to 30%.
Results: In an open circuit with gravity siphon venous drain, angled cannulae drain more than straight ones regardless the amount of suction applied to the venous line (16 Fr straight cannula (S) drains 90 ml/min less than a 16 Fr angled (A) with a siphon gravity). The same flow can be obtained with lower cannula size and higher suction (i.e. 12 A with and -30 mmHg). Tables have been created to list how the flow varies according to the size of the cannulas, the size of the venous tubes, and the amount of suction applied to the system.
Conclusions: Vacuum assisted venous drainage allows the use of smaller cannulae and venous lines to maintain a good venous return, which is very useful during minimally invasive approaches. The present study should be considered as a preliminary attempt to create a scientific-based starting point for a uniform the use of VAVD.
Keywords: cardio-pulmonary bypass; experimental study; vacuum assisted drainage
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
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
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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