1,720,973 research outputs found
L’infezione di cellule intestinali Caco-2 con il virus influenzale a promuove l’adesività di ceppi E. coli isolati da pazienti con malattia di Crohn.
No full textIl virus influenzale aumenta l’adesività di ceppi Escherichia coli isolati da pazienti affetti da malattia di Crohn in cellule intestinali.
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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
Molecular characterisation of extensively drug-resistant Acinetobacter baumannii: first report of a newsequence type in Italy.
No full textProprietà invasive in cellule prostatiche e profilo di virulenza di Escherichia coli isolati da infezione del tratto urinario in pazienti comunitari
No full textE. coli è altamente adattato alla colonizzazione del tratto urinario: la presenza di numerose adesine, siderofori, tossine, rivestimenti polisaccaridici e altri fattori di virulenza possono favorire l’adesione al tessuto mucoso dell’ospite permettendo l’elusione della difesa immune e l’invasione dei tessuti. E. coli urinari sono in grado di invader e persistere nel citoplasma di cellule epiteliali prostatiche. Ceppi di E. coli isolati da pazienti comunitari con infezioni urinarie sono stati caratterizzati per capacità adesiva e invasiva in cellule prostatiche RWPE-1
Dominant Genotypes in Mucosa-Associated Escherichia Coli Strains from Pediatric Patients with Inflammatory Bowel Disease
No full textEscherichia coli (E. coli), a predominant facultative anaerobe of the human colonic flora, has been thought to participate in the pathogenesis of inflammatory bowel disease (IBD). Increased numbers of mucosa-associated E. coli have been observed in adult IBD patients; furthermore, some E. coli strains from Crohn's disease (CD) patients have been shown to adhere to intestinal epithelial cells and invade them, as well as to replicate extensively into macrophages. It has also been suggested that some E. coli genotypes are more likely than others to be associated with CD in adults. There are no studies on the molecular characterization of mucosa-associated bacteria in children with pediatric IBD. Aims: children with IBD were investigated in order to characterize mucosa-associated E. coli strains and to assess if a particular subset of E. coli strains could be associated with IBD in these subjects. Methods and subjects: we analyzed genomic profile, phylogenetic grouping, virulence-gene carriage, different biochemical and enzymatic properties, and adhesive/invasive abilities of 60 E. coli strains isolated from mucosal biopsies of pediatric patients affected by CD (12 cases), ulcerative colitis (UC) (7 cases), and from those of 19 children with functional intestinal disorders who served as controls. Median (and ranges) age (years) was 14.0 (12-17), 10.0 (8-13), 12.7 84-16), respectively. Patients underwent ileo-colonoscopy as a step of their diagnostic approach after parental written consensus. The study was approved by the ethical committee of the Faculty. Results: in E. coli strains deriving from IBD patients and from controls no noteworthy differences were found in the distribution of phylogroups, in the adhesive properties as well as in the occurrence of virulence-related genes . However, the genetic profile examination revealed two large clusters of genetically linked E. coli strains from IBD patients: in the first cluster were grouped 92% of E. coli strains isolated from CD patients, distributed between two sub-clusters; in the second cluster 78% of strains isolated from UC and 77% from controls, distributed between two sub-clusters, respectively. Conclusions: in children with IBD, whereas phenotypic characterization failed to identify peculiar pathogenetic strains, genomic analysis was able to define a close genetic relatedness among E. coli strains associated with CD and UC gut mucosa
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
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