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Obstructive ureterocele-an ongoing challenge
No full textUreterocele is a cystic dilatation of the intravesical
ureter that is most commonly observed in females
and children, and usually affects the upper moiety of a
complete pyeloureteral duplication. According to their
position, ureteroceles are divided into intravesical, when
the ureterocele is completely contained inside the
bladder, and extravesical when part of the cyst extends
to the urethra or bladder neck. Most ureteroceles are
diagnosed in utero or immediately after birth during an
echographic screening of renal malformations. Severe,
febrile urinary tract infection is the most common
postnatal presentation of ureteroceles, but they may,
rarely, prolapse and acutely obstruct the bladder outlet.
Once an ureterocele is identified sonographically, a
voiding cystourethrogram to detect vesicoureteral reflux
(VUR) and a 99m-technetium dimercapto-succinic acid
renal scan to evaluate the function of the different portions
of the kidney are mandatory. VUR in the lower
pole is observed in 50% of cases and in the contralateral
kidney in 25%. Simple endoscopic puncture of the ureterocele
has recently been advocated as an emergency
therapy for infected or obstructing ureteroceles and as
an elective therapy for intravesical ureteroceles. The rate
of additional surgery after elective endoscopic puncture
of an orthotopic ureterocele ranges from 7 to 23%.
Treatment of ectopic ureteroceles is more challenging
and both endoscopic puncture and upper pole partial
nephrectomy frequently require additional surgery at the
bladder level. The reoperation rate after endoscopic
treatment varies from 48 to 100%. It is 15 to 20% after
upper pole partial nephrectomy if VUR was absent
before the operation, but is as high as 50–100% when
VUR was present. Thus, endoscopic incision is appropriate
as an emergency treatment or when dealing with a
completely intravesical ureterocele. Upper pole partial
nephrectomy is the elective treatment for an ectopic
ureterocele without preoperative VUR. In an ectopic
ureterocele with VUR, no matter which type of primary
therapy has been chosen, a secondary procedure at the
bladder level, involving ureterocele removal and reimplantation of the ureter(s), should be anticipated
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
Derivazione interna con stent J-J nel megauretere ostruttivo. XVII Congresso Società Italiana di Urologia Pediatrica
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