1,721,033 research outputs found
Targeting vascular niche by parathyroid hormone.
No full textCurrently, the parathyroid hormone (PTH) is a drug approved for use in humans only in bone metabolism diseases, as the osteoporosis. The PTH acts primarily by binding to its principal receptor, PTH/PTHrP-R, a member of the class B G protein-coupled receptor (GPCR) family that includes together receptors for other therapeutically important peptide hormones. PTH plays a central role in the maintenance of calcium and phosphate homeostasis and bone health. It acts to maintain bone and mineral homeostasis through several mechanisms: elevation of blood calcium by increasing osteoclastic bone resorption; enhancement of renal calcium reabsorption; stimulation of renal 1,25-dihydroxyvitamin D synthesis, leading to increased intestinal calcium absorption; and promotion of phosphaturia via inhibition of renal tubular transepithelial phosphate reabsorption . However, many findings indicate that the PTH could be a future drug essential in therapy of cardiovascular diseases through multiple effects on hematopoietic stem cells niche. In adult bone marrow, the hamatopoietic stem cells are located in the trabecular endosteum (osteoblastic niche) or sinusoidal perivascular areas (vascular niche). A plausible function for the vascular niche is to assist hematopoietic stem cells in transendothelial migration, which is important during both homing and mobilization. Indeed, in experimental models, PTH treatment increases migration of angiogenic CD45+/CD34+ progenitor cells to the hindlimb ischemia as well as in the ischemic heart, promoting tissue repair by enhanced neovascularization and cell survival
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
CXCR4-CXCL12-Dependent Inflammatory Network and Endothelial Progenitors.
No full textThe endothelial progenitor cells (EPCs) are angiogenic cells having properties similar to those of embryonal angioblasts. The number and function of EPCs are affected by a variety of conditions, including cytokines and chemokines, which are pivotal inflammatory signaling molecules. The purpose of this paper is to review current knowledge about the role of these progenitor in different vascular diseases, emphasizing the important biological role played from the CXCR4-CXCL12 axis in the cellular trafficking. Indeed, as described in detail in this review, the CXCR4/CXCL12 interaction produces pleiotropic effects in stem cells and plays a pivotal role in several processes related to development, tissue regeneration and development/progression of malignancies
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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