1,720,982 research outputs found

    Oncocytic carcinoma of the breast: frequency, morphology and follow-up

    No full text
    Oncocytic breast carcinomas are tumors composed of no fewer than 70% of oncocytic cells (World Health Organization). The purpose of this study was to determine the frequency, morphologic, immunohistochemical, and clinical features of invasive oncocytic carcinoma in a large series. Twenty-eight cases of putative oncocytic breast carcinoma (selected cases group) and 76 consecutive cases of invasive breast carcinoma (consecutive cases group) were analyzed. Immunohistochemistry for mitochondria, gross cystic disease fluid protein 15, chromogranin, estrogen receptor, progesterone receptor, androgen receptor, HER2/Neu, cytokeratin 7, cytokeratin 14, epithelial membrane antigen, and differentiation cluster 68 was performed. Score for mitochondria was based on intensity and percentage of immunopositive cells. Classes were as follows: (1) oncocytic carcinoma: at least 70%, 3+; (2) mitochondrion-rich carcinoma: 50% to 70%, 3+, or more than 50%, 2+; and (3) all the other cases were referred to as invasive breast carcinoma. Ultrastructural examination was available for 6 cases of oncocytic carcinoma. Morphologic and immunohistochemical features of the 3 groups were compared using Fisher exact test (P<.05). For overall survival analysis, Kaplan-Maier curves were compared using log-rank and Wilcoxon tests (P<.05). Our results suggest that oncocytic breast carcinoma is a morphologic entity with distinctive histologic and ultrastructural features. Mitochondrion-rich carcinomas are histologically similar to oncocytic carcinomas and constitute 19.7% of all invasive carcinomas, indicating that cytoplasmic eosinophilia in breast cancer cells is often due to accumulation of mitochondria. Oncocytic carcinomas and mitochondrion-rich carcinomas are more often grade III tumors and show human epidermal growth factor receptor 2 overexpression. Clinical features and overall survival of oncocytic carcinomas are not distinctive because they are similar to those of the other cases when matched for grade and stage. (C) 2011 Elsevier Inc. All rights reserved

    Going Beyond Counting First Authors in Author Co-citation Analysis

    Full text link
    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

    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 link
    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

    Dispelling the Myths Behind First-author Citation Counts

    Full text link
    We 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

    Author Index

    No full text
    Nao informado

    IGFBP2 as an Immunohistochemical Marker for Prostatic Adenocarcinoma

    No full text
    AIM: The aim of the study was to evaluate the immunohistochemical expression of insulin-like growth factor binding protein 2 (IGFBP2) in normal epithelium, high-grade prostatic intraepithelial neoplasia (HG-PIN), and prostatic adenocarcinoma (PAc), in patients hormonally untreated and in those having undergone complete androgen ablation. MATERIALS AND METHODS: IGFBP2 expression was evaluated in PAc, HG-PIN, and normal-appearing epithelium in 40 radical prostatectomies from hormonally untreated patients and 10 radical prostatectomies from patients under complete androgen ablation before surgery. The study also included the initial biopsies of such patients, and an additional 10 simple prostatectomies from patients with bladder outlet obstruction. Statistics included receiver-operator characteristic curves, the Wilcoxon test, and the Spearman test. Results were compared with α-methylacyl-CoA racemase. RESULTS: The principal findings were: (1) IGFBP2 was not expressed in normal ducts and acini of the transition and peripheral zones; (2) IGFBP2 was expressed in the cytoplasm of untreated PAc and, to a lesser extent, in HG-PIN; (3) it was also expressed in PAc and HG-PIN after complete androgen ablation, but to a lesser extent than in the untreated neoplasms; (4) α-methylacyl-CoA racemase was expressed both in PAc and HG-PIN, the level being similar in both lesions and lower in the specimens from the patients having undergone androgen ablation. CONCLUSIONS: Results obtained show that IGFBP2 is expressed in invasive PAc, whereas its expression in HG-PIN is low. These findings can be helpful in the correct diagnosis of PAc both in biopsies and in surgical specimens, mainly in untreated patients
    corecore