1,720,962 research outputs found
Incidence of hepatic and extra-hepatic malignancies in primary biliary cirrhosis (PBC).
No full textThe 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
Chronic atrophic gastritis and Helicobacter pylori infection in primary biliary cirrhosis: A cross-sectional study with matching
No full textBACKGROUND/AIMS:
Primary biliary cirrhosis (PBC) is a chronic liver disease characterized by exocrine gland impairment. Up to now there have been no reports dealing with gastric mucosa involvement in this autoimmune condition, which is frequently associated with Sjögren's syndrome. The aim of this study was to investigate the morphologic, biochemical and immunological features of the gastric mucosa in PBC.
METHODS:
A cross-sectional study with matching was performed. Thirty-three PBC patients (30 F, 3 M, mean age 58 years; 17 with stage II-III, and 16 with stage IV disease) and 33 sex- and age-matched dyspeptic controls were included. Six biopsy specimens from the fundus (2), body (2) and antrum (2) were taken from all patients and controls. A serological assessment was performed for each subject, i.e. pepsinogen A (PGA), pepsinogen C (PGC), gastrin (G), and antibodies against Helicobacter pylori (anti-Hp IgG).
RESULTS:
Endoscopic gastritis was found in 22 PBC patients (66.6%). There was no difference between PBC patients and controls regarding the percentage of subjects with mild, moderate, severe or atrophic gastritis (AG). There was no difference in gastric mucosal involvement between PBC subjects with or without secondary Sjögren's syndrome. A discrepancy was observed in the data obtained with respect to Helicobacter pylori (H. pylori) infection. H. pylori colonization was significantly more frequent in controls than in PBC patients (79% vs 49%, p < 0.002), but anti-Hp IgG were detected in the same percentage in the two groups (90% vs 83% respectively). There was no difference between the two groups in the PGA, PGC, PGA/PGC ratio, or gastrin. Eight PBC patients had esophageal varices.
CONCLUSIONS:
PBC patients are not characterized by chronic atrophic gastritis. Even though they present chronic gastritis with the same prevalence as dyspeptic controls, and show signs of previous H. pylori infection as frequently as dyspeptic patients, they are actually much less frequently infected. The reasons for this observation are unclear
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
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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