1,720,956 research outputs found
Comparison of two models for predicting non-sentinel lymph node metastases in sentinel lymph node-positive breast cancer patients
Sentinel lymph node biopsy in patients with pure and high risk ductal carcinoma in situ of the breast
Familial and Sporadic Breast Cancer: Differences in Clinical, Histopathological and Immunoistochemical Features
In the present study, the authors investigated the clinical, histopathological, and immunohistochemical features in familial breast cancer (FBC) patients and compared them with findings in sporadic breast cancers (SBCs); hormone receptor status was stratified by age. A total of 849 patients treated for breast cancer were included in the study. The patients were stratified into 2 groups: FBC, 160 patients (19%), and SBC, 689 patients (81%). FBC tumors differed from SBC tumors by earlier age of diagnosis and low content of progesterone receptor (PR). These characteristics should be of value in evaluating the possibility of mutation and in targeting mutation screening in such families. PR gene polymorphism leads to an increased risk of breast cancer because it determines inadequate control of estrogen receptor (ER)-driven proliferative function. ER+/PR- tumors more frequently showed HER2 (human epidermal growth factor receptor) overexpression and represent a distinct subset in FBC patients. The authors suggest that late-onset FBCs need more intensive therapy and a more careful follow-up
Going Beyond Counting First Authors in Author Co-citation Analysis
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
“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
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
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
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