1,721,008 research outputs found
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
Decorin transfection in breast cancer cells induces proteomic modulation and downregulation of matrix proteases.
No full textHerceptin-resistance in breast cancer cells: a proteomic study.
No full textHER-2 is a cell membrane protein that belongs to the ErbB family of receptor tyrosine kinases (HER-1, HER-2, HER-3, HER-4). The over-expression of HER-2, which results in the 25-30% of breast cancer patients, is considered a predictive and prognostic marker for breast cancer malignancy and invasiveness and makes HER-2 an excellent therapeutic target.
In the last years new therapeutic strategies have been improved in order to better deal tumor diseases an to minimize collateral effects due to classic chemotherapy in patients.
In this way, a new approach was the somministration of humanized antibodies directed against tumor-associated molecular targets. Among these ones Herceptin, an anti-neoplastic humanized monoclonal antibody (Herceptin®, Roche, CH), has been shown to be active against breast cancer cells over-expressing HER-2 receptor.
Unfortunately the initial response to Herceptin-based regimens is followed by drug-resistance occurring within 1 year in the majority of patients. Thus it becomes critical to understand the molecular mechanisms underlying primary or acquired Herceptin resistance in order to improve the survival of breast cancer patients whose tumors overexpress HER2.
On these bases, we focused our attention to investigate the effects caused by Herceptin treatment on SK-BR-3 breast cancer cells, which overexpress HER-2. To obtain drug-resistant cells, SK-BR-3 were treated with 10 μgr/ml of drug, until cells growth rate became synchronous compared to untreated parental cells. Parental and resistant cells were then properly collected and subjected to cell-lysis to obtain protein extracts, while respective conditioned media were harvested to perform analyses of cell-released gelatinolic activities, such as MMP-2 and MMP-9. These investigations are justified by previous observation of our group, showing a certain degree of correlation between gelatinase expression and HER-2 overexpression in vivo [1]. Protein extracts were subjected to IPG-2D electrophoresis, firstly to evaluate proteomic profiles of both resistant and parental cells, secondly to detect differentially expressed proteins in two above mentioned experimental conditions and thirdly to identify new Herceptin-resistance related proteins by means of MALDI-TOF mass spectrometry. The results so far obtained, have shown that prolonged Herceptin treatment induces dramatic changes in malignant resistant cells, such as rearrangement of cytoskeletal structures, evident effects on expression of proteins involved in cytoskeleyton remodelling, metabolic processes, stress responses and cell cycle and proliferation control. We suggest that present data may contribute significantly to the knowledge of the mechanisms underlying Herceptin drug resistance on breast cancer cells.
[1]La Rocca, G., Pucci-Minafra, I., Marrazzo, A., Taormina, P. & Minafra, S. 2004. British Journal of Cancer, 90: 1414-1421
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
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