1,720,967 research outputs found
Growth hormone in heart failure revisited: An old story retold
Full text linkHeart failure (HF) is a disease characterized by increasing prevalence, huge direct and indirect costs, and an ominous prognosis, worse than many cancers. At the beginning of the 90s, growth hormone (GH) was proposed as potential adjunctive therapy in HF mostly due to its growth-promoting, vasodilating, and anti-apoptotic actions. However, although several uncontrolled clinical studies showed that GH therapy improved several cardiovascular parameters, two robust trials failed to confirm these findings. Dwelling upon potential explanations for such apparent discrepancy led to the hypothesis that HF patients exhibit an inhomogeneous basal activity of the GH/insulin-like growth factor 1 (IGF-1) axis, ranging from GH/IGF-1 deficiency to GH resistance. This complex phenomenon was then reconsidered in the context of the so-called multiple hormone deficiency syndrome (MHD), that is the recognition that HF is characterized not only by the hyperactivation of several signaling pathways including the adrenergic, the renin-angiotensin-aldosterone and cytokine systems, but also by a reduced anabolic drive leading to a state of anabolic/catabolic imbalance. Mounting evidence support the concept that such imbalance is not a mere epiphenomen, since it exerts a significant impact on clinical performance and more importantly, on survival. Therefore, the paradigm shift to reconsider HF as MHD represented the underpinning to implement clinical trials focused on hormone replacement therapies in congestive heart failure (CHF). With regard to GH replacement therapy, one controlled single-blind study yielded promising results, and we are currently conducting a double-blind controlled trial, as well a large Registry study to evaluate the impact of MHD on HF progression
Growth Hormone Therapy in Heart Failure
No full textSeveral studies have shown that growth hormone (GH) deficiency is common in chronic heart failure and is associated with impaired functional capacity and poor outcomes. Data derived from animal models showed beneficial effects of GH treatment on peripheral vascular resistance, cardiac function, and survival. Despite this solid background, when translated onto the clinical field, these results did not lead to unequivocal results. This article focuses on the assessment of GH deficiency in chronic heart failure, the underlying molecular background, the impact on disease progression and outcomes, the effects of GH therapy, and the novel and more encouraging approach of GH-replacement therapy
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
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