1,721,102 research outputs found
Impact of prostate cancer multifocality on its biology and treatment.
No full textAny focal therapy requires correct localization of the lesion; consequently, much effort is now devoted to accurate characterization of the spatial distribution of the tumor within the prostate. One of the greatest difficulties in the localization of prostate cancer is its frequent multifocality, but prostate cancer is unifocal in 13% to 43.7% of cases and unilateral in 19.2%. In cases of multifocality, it seems that the index tumor is the biologic driving force behind the malignant potential of prostate cancer. Not only is the Gleason score of the secondary nodes lower than that of the index node, but 80% of the secondary nodes are smaller than 0.5 cc and almost all extraprostatic extensions are associated with the largest cancers. While current evaluation with 12 to 18 core biopsies may be adequate to determine the index lesion, transperineal three-dimensional mapping biopsy of the prostate should be undertaken if greater accuracy is needed
TP53 in urologic tumors
No full textTP53, a gene located on chromosome 17p13, encodes a nuclear protein (p53) involved in cell cycle regulation. This protein degrades in 20 minutes. However, the inactivated gene can produce a protein with a half-life 4-20 times longer than that of the wild type; it can be demonstrated by immunohistochemistry. Unfortunately, all the antibodies recognize both proteins, and the determination of a cutoff in the percentage of positive nuclei is required for the detection of cases with correlation of the TP53 mutation. In urologic tumors, p53 overexpression determination can be diagnostic help in low grade superficial bladder cancer, in cases of cystectomy and pN0, and in penile cancer without clinically involved lymph nodes. It does not seem useful in renal cell carcinoma or testicular germ cell tumors, and its utility is limited in prostate carcinoma
Morphological identification of the patterns of prostatic intraepithelial neoplasia and their importance
No full text
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
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