1,720,962 research outputs found
A novel nomogram to predict the probability of prostate cancer on repeat biopsy
No full textPURPOSE: We developed a predictive model that incorporates clinical data and prostate specific antigen kinetic from general practice to detect prostate cancer in patients with a previously negative prostate biopsy.
MATERIALS AND METHODS: From January 2001 to January 2007 data on 419 men who underwent repeat prostate biopsy with 12 or more cores were used to develop the nomogram. From February 2007 to June 2007 data on 63 men with the same criteria were used to validate the nomogram. The factors that we evaluated for the risk of a positive repeat prostate biopsy were patient age, digital rectal examination findings, total prostate specific antigen, the free-to-total prostate specific antigen ratio, prostate specific antigen density and slope, and previous high grade prostatic intraepithelial neoplasia.
RESULTS: On multivariate logistic regression all factors except age and prostate specific antigen showed significant ability to predict the outcome of 12-core repeat prostate biopsy. In the validation group the AUC of the predicted results from the model was 0.856 (95% CI 0.744-0.931), better than that of prostate specific antigen, the free-to-total prostate specific antigen ratio, and prostate specific antigen density and slope (p <0.05).
CONCLUSIONS: We successfully developed an accurate model to predict the outcome of repeat prostate biopsy. Adding the free-to-total prostate specific antigen ratio, digital rectal examination, prostate specific antigen and slope, and history of high grade prostatic intraepithelial neoplasia sharply improves the accuracy of our model
Genetic factors regulating inflammation and DNA methylation associated with prostate cancer.
No full textBACKGROUND:
Prostate cancer (PCa) displays a strong familiarity component and genetic factors; genes regulating inflammation may have a pivotal role in the disease. Epigenetic changes control chromosomal integrity, gene functions and ultimately carcinogenesis. The enzyme glycine-N-methyltransferase (GNMT) contributes to S-adenosylmethionine level regulation and, by affecting DNA methylation, influences gene expression. The genotype and allele distribution of single-nucleotide polymorphisms (SNPs) in the promoter regions of vascular endothelial growth factor (VEGF), interleukin (IL)-10, IL-1β, alpha-1-antichymotrypsin (ACT) and GNMT genes, the level of global DNA methylation and the influence of GNMT SNP upon DNA methylation in a PCa case-control study have been investigated.
METHODS:
SNPs of VEGF (rs699947), ACT (rs1884082), IL-1β (rs16944), IL-10 (rs1800896) and GNMT (rs9462856) genes were assessed by PCR or by real-time PCR methods. DNA methylation was assessed by an ELISA assay.
RESULTS:
Frequencies of the VEGF AA genotype, the IL-10 A allele and GNMT T allele were higher in PCa. The concomitant presence of the AA genotype of VEGF, the A allele of IL-10 and T allele of GNMT increased the risk of PCa. Total DNA methylation was decreased in PCa; control GNMT T carriers (T+) showed the highest level of DNA methylation.
CONCLUSIONS:
SNPs in VEGF, IL-10 and GNMT genes might have a synergistic role in the development of PCa. The GNMT T allele may influence PCa risk by affecting DNA methylation and prostate gene expression. Our observations might help implement the screening of unaffected subjects with an increased susceptibility to develop PCa
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe 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
Get PDF“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
Get PDFWe 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
Get PDFWe 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
- …
