1,720,995 research outputs found

    Going Beyond Counting First Authors in Author Co-citation Analysis

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    The 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

    Incidence of hepatic and extra-hepatic malignancies in primary biliary cirrhosis (PBC).

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    The aim of this study was to analyze the incidence of malignancies in a large series of PBC patients from Italy. The overall sample included 178 patients (10 M, 168 F). The mean age at presentation was 52 yrs (range 29-74); 17 patients had histological stage I, 52 stage II, 66 stage III, 44 stage IV. The follow-up period ranged from 1 to 16 years (mean 5 years). During the follow-up, extra-hepatic malignancies developed in 6 cases (3.3%), and hepatocellular carcinoma (HCC) in a further 4 patients, all associated with cirrhosis (2.2%). Breast cancer developed only in one patient, resulting in a crude incidence rate of 130/100.000 person years among females. The calculated crude incidence of HCC was 492.4/100.000 person years. Three of the four patients with HCC had a superinfection with HCV. In conclusion, the incidence of breast cancer is not significantly increased. HCC has a relatively high prevalence in PBC and HCV superinfection may play an important role in favouring HCC

    Variations on the Author

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    “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

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    We 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

    Capsaicin-like effect of resiniferatoxin in the rat stomach

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    Neurochemical and functional studies were performed to investigate and to compare the effects of resiniferatoxin and capsaicin in the rat stomach. Neonatal administration of resiniferatoxin (0.6-1.6 μmol/kg subcutaneously (s.c.)) produced a marked decrease in gastric calcitonin gene-related peptide-like immunoreactivity in both secretory and non-secretory region of the stomach. Almost complete depletion of the peptide was determined by neonatal administration of capsaicin (164 μmol/kg s.c.). Vasoactive intestinal polypeptide-like immunoreactivity was concomitantly unaffected by resiniferatoxin or capsaicin, thus showing the selectivity of action of the neurotoxins on gastric afferent fibers. Oral administration of an equimolar dose (0.3 nmol/kg) of resiniferatoxin or capsaicin together with 50% ethanol reduced at a similar extent gastric haemorrhagic lesions produced by the mucosal barrier-breaker agent. These findings provide evidence that resiniferatoxin and capsaicin may act on a common neuronal target in the rat stomach and that the acute exciting (protective) effect is of the same magnitude. © 1994
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