1,720,997 research outputs found
No-React (R) Injectable BioPulmonic (TM) valves re-evaluated: discouraging follow-up results
No full textOBJECTIVES: The No-React (R) Injectable BioPulmonic (TM) valve (BioIntegral) was introduced for minimally invasive off-pump replacement of the pulmonary valve almost 10 years ago. We present our mid-to long-term follow-up results. METHODS: We conducted a retrospective analysis of all 7 patients treated at our institution at the median age of 9 (range 1-24) years. The children underwent cardiac catheterization when worsening strain on the right heart was suspected after examining their medical history and/or observing significant changes on echocardiography. RESULTS: After a median follow-up period lasting 5.2 (range 0.7-6.7) years, all patients presented the indication for recatheterization, particularly because the maximum instantaneous velocity measured by Doppler had revealed systolic gradients of a median 63 (dP 18-74) mmHg across the right ventricular outflow. Catheterization confirmed severe stenosis in 2, and moderate stenosis together with moderate insufficiency in 4 patients. We observed two principal failure mechanisms: technical problems resulting from poor alignment to the right ventricular outflow tract and structural problems leading to neointimal proliferation even in cases with appropriate prosthesis positioning. At median of 5.7 (0.7-7) years after implantation, 6 of the 7 patients underwent valve rereplacement. Redo surgery was necessary in 3, and percutaneous valve-in-valve implantation in the remaining 3 patients. Histological analysis of two explanted valves confirmed significant neointima proliferation and thickened valve cusps leading to stenosis of the graft. CONCLUSIONS: These mid-term results after implantation of the No-React (R) Injectable BioPulmonic (TM) valve are disappointing. Graft failure was mainly due to neointimal formation and valve malposition
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
Untersuchung der Langzeiteffekte einer frühzeitigen Immunsuppression mit mTor-Inhibitoren nach pädiatrischer Herztransplantation
No full textDie Wahl einer optimalen Immunsuppression ist entscheidend für ein möglichst gutes Transplantationsergebnis und die Minimierung der auftretenden Nebenwirkungen durch die Therapie. Insbesondere bei einem Kollektiv von Kindern, bei denen die Entwicklung des Immunsystems noch nicht abgeschlossen ist und viele Medikamente besondere pharmakologische Eigenschaften zeigen, stellt die Therapie mit einer hohen klinischen Effektivität bei gleichzeitig minimierter Toxizität eine Herausforderung dar. Ziel dieser Arbeit lag darin zu untersuchen, inwieweit die frühzeitige Initiierung von mTor-Inhibitoren nach Herztransplantation bei Kindern, nicht zu vermehrten relevanten Nebenwirkungen führt, die Anzahl chronischer Cytomegalievirus-Infektionen minimiert und die Entwicklung einer Transplantvaskulopathie verhindert werden kann. Im Vergleich zu veröffentlichten Daten früherer Studien, konnten keine relevanten Unterschiede in Bezug auf das Gesamtüberleben, das Auftreten einer Abstoßungsreaktion oder eines Posttransplantationslymphoms gefunden werden. Durch den frühen Therapiebeginn mit Everolimus könnte die kumulative Dosis von Cyclosporin A möglicherweise reduziert werden, was sich positiv auf die Funktion der Nieren auswirken kann, jedoch fehlte hierfür ein direkter Nachweis. Es ist bekannt, dass mTor-Inhibitoren durch ihre antiproliferativen und antimigratorischen Wirkungen eine effektive Möglichkeit der Prävention einer Transplantvaskulopathie darstellen. Dennoch ist es bemerkenswert, dass im gesamten Nachbeobachtungszeitraum dieser Arbeit unter allen Studienteilnehmer/innen kein einziger Fall einer Transplantvaskulopathie auftrat. Weiterhin wurden nicht vermehrt auftretende, starke klinische Nebenwirkungen der Therapie mit Everolimus beobachtet, insbesondere kaum solche, die eine Therapieunterbrechung notwendig machten. Die Ergebnisse dieser Arbeit zeigen, dass die Therapiekombination aus Everolimus, Cyclosporin A und initial einem Steroid eine sichere und effektive Möglichkeit der Immunsuppression nach Herztransplantation bei Kindern darstellt. Jedoch sind weitere Untersuchungen, insbesondere mit direkten Vergleichsgruppen erstrebenswert, um die Therapie der Immunsuppression weiterhin zu optimieren und eine möglichst hohe Lebensqualität der Kinder zu gewährleisten
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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