1,721,021 research outputs found
Coronary button dehiscence after the modified Bentall procedure
No full textThe modified Bentall procedure (MBP), after over 50 years from its introduction, still represents an extremely valid option in patients with aortic valve disease and aneurysms of the ascending aorta or the aortic root. Late complications following MBP are substantially rare but whenever they occur they represent a real surgical challenge. For this reason, we were very interested in reading the article by Comentale et al. published in the Journal of Cardiac Surgery. The authors report a patient who developed after 18 months a giant pseudoaneurysm of the right coronary button which was repaired successfully
Mitral valve repair with artificial chordae. A review of its history, technical details, long-term results and pathology
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
Single center experience with the Sorin Bicarbon prosthesis. A 17-year follow-up
No full textObjective: To evaluate the long-term results of aortic valve replacement (AVR) and mitral valve replacement
(MVR) with the Sorin Bicarbon prosthesis (SBP).
Methods: Five hundred seven patients (306 men, 201 women), mean age 62 10 years (range, 21-86 years),
received an SBP between 1994 and 2000; AVR was performed in 344 (67%) and MVR in 163 (33%). The main
concomitant procedure was coronary artery grafting in 79 patients (16%). Follow-up was 99%complete; mean
follow-up was 12.7 4.0 years with a cumulative duration of follow-up of 6475 patient-years in the entire group
(4348 patient-years for AVR and 2124 patient-years for MVR).
Results: Hospital mortality was 2.7% (AVR, 2.03%; MVR, 4.3%). There were 169 late deaths (AVR, 128;
MVR, 41). Actuarial survival at 17 years is 49.7% 5.3% for AVR and 62.0% 6.1% for MVR. At the
last follow-up, 310 survivors (199 AVR, 111 MVR) are in New York Heart Association functional class I or
II. At 17 years, actuarial freedom from valve-related deaths, embolism, and bleeding is 89.8% 4.8%,
85.8% 5.4%, and 96.2% 1.2% after AVR, and 91.9% 3.9%, 96.3% 1.8%, 95.0% 2.9% after
MVR. Reoperation was required in 5 patients with AVR (thrombosis in 4 and perivalvular leak in 1). Actuarial
freedom from reoperation is 98.1% 0.8% after AVR and 100% after MVR; freedom from endocarditis is
100% after AVR and 99.2% 0.7% after MVR. No cases of intrinsic structural valve failure were observed.
Conclusions: The SBP has shown excellent results in terms of clinical improvement and freedom from
valve-related complications, even up to 17 years after AVR and MVR. It therefore seems to be a safe option
whenever a mechanical prosthesis is needed. (J Thorac Cardiovasc Surg 2014;148:2039-44
Performance of the Hancock porcine bioprosthesis following aortic valve replacement: considerations based on a 15-year experience.
No full textVariations 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
- …
