1,721,233 research outputs found
Emerging role of the KRAS-PDK1 axis in pancreatic cancer
Full text linkPancreatic cancer is a highly aggressive tumour that is very resistant to treatments and it is rarely diagnosed early because of absence of specific symptoms. Therefore, the prognosis for this disease is very poor and it has the grim supremacy in terms of unfavourable survival rates. There have been great advances in survival rates for many types of cancers over the past few decades but hardly any change for pancreatic cancer. Mutations of the Ras oncogene are the most frequent oncogenic alterations in human cancers. The frequency of KRAS mutations in pancreatic cancer is around 90%. Given the well-established role of KRAS in cancer it is not surprising that it is one of the most attractive targets for cancer therapy. Nevertheless, during the last thirty years all attempts to target directly KRAS protein have failed. Therefore, it is crucial to identify downstream KRAS effectors in order to develop specific drugs able to counteract activation of this pathway. Among the different signalling pathways activated by oncogenic KRAS, the phosphoinositide 3-Kinase (PI3K) pathway is emerging as one of the most critical KRAS effector. In turn, PI3K activates several parallel pathways making the identification of the precise effectors activated by KRAS/PI3K more difficult. Recent data identify 3-phosphoinositide-dependent protein kinase 1 as a key tumour-initiating event downstream KRAS interaction with PI3K in pancreatic cancer
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
Comparative evaluation of different techniques of surface preparation for occlusal sealing.
No full textEuropean journal of paediatric dentistry : official journal of European Academy of Paediatric Dentistry
Volume 8, Issue 3, September 2007, Pages 119-123
Comparative evaluation of different techniques of surface preparation for occlusal sealing. (Article)
Mazzoleni, S.,
De Francesco, M.,
Perazzolo, D.,
Favero, L.,
Bressan, E.,
Ferro, R.,
Stellini, E.
Department of Paediatric Dentistry, University of Padua, Italy.
Abstract
AIM: Aim of this experiment is the efficacy evaluation of three different types of surface preparation techniques by microleakage assessment of two different sealing materials. MATERIALS AND METHODS: Sixty teeth were used for the experiment: half were treated with Admira seal (Voco) and the remaining half with Delton FS+ (Dentsply). Each group was then divided into three subgroups, which underwent three different preparation techniques before sealant placement: mechanical brushing, air abrasion and Intensive bur FG 40D4, respectively. After immersion of the specimens in methylene blue solution, the degree of microleakage was assessed by mean of optic microscope. RESULTS: Results show no microleakage in samples treated with air abrasion, followed by the samples treated with mechanical brushing. The teeth prepared by bur treatment before sealant application show a significant number and degree of marginal infiltration. CONCLUSION: It can be concluded that air abrasion technique is able to guarantee a reliable seal of occlusal surfaces
Role of the Lysophosphatidylinositol/GPR55 axis in cancer
No full textLysophosphatidylinositol (LPI) is a well-known bioactive lipid that is able to activate signalling cascades relevant to cell proliferation, migration, survival and tumourigenesis. It is well-established that the G protein-coupled receptor 55 (GPR55) is the specific receptor for LPI. Several investigations have demonstrated that the signalling pathways activated by LPI through its receptor GPR55 play a pivotal role in different cancer type. This review focuses on the role of the LPI/GPR55 axis, in particular with regards to its pharmacological potential therapeutic exploitation.</p
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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