1,720,956 research outputs found
The Spigelman Staging System and the Risk of Duodenal and Papillary Cancer in Familial Adenomatous Polyposis: A Systematic Review and Meta-Analysis
No full textINTRODUCTION: Individuals with familial adenomatous polyposis (FAP) have an almost 20% lifetime risk of duodenal adenocarcinoma, currently the leading cause of death in FAP. The Spigelman staging system provides guidance on the surveillance intervals and timing of prophylactic surgery. Still, its accuracy in predicting duodenal and papillary cancer development has not been systematically evaluated. We investigated the sensitivity and cancer risk of the Spigelman stages. METHODS: We performed a systematic review on PubMed, MEDLINE, EMBASE, and Cochrane and used a random-effects model to pool effect sizes. RESULTS: After removing duplicate entries, we screened 1,170 records and included 27 studies for quantitative analysis. Once duodenal polyposis reaches Spigelman stage IV, the risk of duodenal and papillary cancers increased to 25% (95% confidence interval [CI] 12%-45%). However, the sensitivity of Spigelman stage IV for these cancers was low (51%, 95% CI 42%-60%), especially for papillary adenocarcinoma (39%, 95% CI 16%-68%). We investigated the reasons behind these low values and observed that duodenal cancer risk factors included polyps >10 mm, polyp count >20, and polyps with high-grade dysplasia. Risk factors associated with papillary cancer included a papilla with high-grade dysplasia or >10 mm. The evidence on other risk factors was inconclusive. DISCUSSION: The current Spigelman staging system had a low sensitivity for duodenal and papillary adenocarcinomas. Two Spigelman variables (duodenal villous histology and polyp count) and the lack of papilla-specific variables likely contributed to the low sensitivity values for duodenal and papillary cancers, respectively. While clinicians may be familiar with its current form, there is an urgent need to update it.INTRODUCTION: Individuals with familial adenomatous polyposis (FAP) have an almost 20% lifetime risk of duodenal adenocarcinoma, currently the leading cause of death in FAP. The Spigelman staging system provides guidance on the surveillance intervals and timing of prophylactic surgery. Still, its accuracy in predicting duodenal and papillary cancer development has not been systematically evaluated. We investigated the sensitivity and cancer risk of the Spigelman stages. METHODS: We performed a systematic review on PubMed, MEDLINE, EMBASE, and Cochrane and used a random-effects model to pool effect sizes. RESULTS: After removing duplicate entries, we screened 1,170 records and included 27 studies for quantitative analysis. Once duodenal polyposis reaches Spigelman stage IV, the risk of duodenal and papillary cancers increased to 25% (95% confidence interval [CI] 12%-45%). However, the sensitivity of Spigelman stage IV for these cancers was low (51%, 95% CI 42%-60%), especially for papillary adenocarcinoma (39%, 95% CI 16%-68%). We investigated the reasons behind these low values and observed that duodenal cancer risk factors included polyps >10 mm, polyp count >20, and polyps with high-grade dysplasia. Risk factors associated with papillary cancer included a papilla with high-grade dysplasia or >10 mm. The evidence on other risk factors was inconclusive. DISCUSSION: The current Spigelman staging system had a low sensitivity for duodenal and papillary adenocarcinomas. Two Spigelman variables (duodenal villous histology and polyp count) and the lack of papilla-specific variables likely contributed to the low sensitivity values for duodenal and papillary cancers, respectively. While clinicians may be familiar with its current form, there is an urgent need to update it
Ten Year Results of Extensive Nodal Radiotherapy and Moderately Hypofractionated Simultaneous Integrated Boost in Unfavorable Intermediate-, High-, and Very High-Risk Prostate Cancer
No full textAims: To report 10-year outcomes of WPRT and HD moderately hypofractionated SIB to the prostate in UIR, HR, and VHR PCa. Methods: From 11/2005 to 12/2015, 224 UIR, HR, and VHR PCa patients underwent WPRT at 51.8 Gy/28 fractions and SIB at 74.2 Gy (EQD2 88 Gy) to the prostate. Androgen deprivation therapy (ADT) was prescribed in up to 86.2% of patients. Results: Median follow-up was 96.3 months (IQR: 71–124.7). Median age was 75 years (IQR: 71.3–78.1). At last follow up, G3 GI–GU toxicity was 3.1% and 8%, respectively. Ten-year biochemical relapse-free survival (bRFS) was 79.8% (95% CI: 72.3–88.1%), disease-free survival (DFS) 87.8% (95% CI: 81.7–94.3%), overall survival (OS) 65.7% (95% CI: 58.2–74.1%), and prostate cancer-specific survival (PCSS) 94.9% (95% CI: 91.0–99.0%). Only two patients presented local relapse. At univariate analysis, VHR vs. UIR was found to be a significant risk factor for biochemical relapse (HR: 2.8, 95% CI: 1.17–6.67, p = 0.021). After model selection, only Gleason Score ≥ 8 emerged as a significant factor for biochemical relapse (HR = 2.3, 95% CI: 1.12–4.9, p = 0.023). Previous TURP (HR = 3.5, 95% CI: 1.62–7.54, p = 0.001) and acute toxicity ≥ G2 (HR = 3.1, 95% CI = 1.45–6.52, p = 0.003) were significant risk factors for GU toxicity ≥ G3. Hypertension was a significant factor for GI toxicity ≥ G3 (HR = 3.63, 95% CI: 1.06–12.46, p = 0.041). ADT (HR = 0.31, 95% CI: 0.12–0.8, p = 0.015) and iPsa (HR = 0.37, 95% CI: 0.16–0.83, p = 0.0164) played a protective role. Conclusions: WPRT and HD SIB to the prostate combined with long-term ADT, in HR PCa, determine good outcomes with acceptable toxicity
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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