1,721,103 research outputs found
Sport-related peripheral nerve injuries : part 1
No full textSport–related strenuous physical activity and trauma are among the causes of peripheral nerves injuries, due in most cases to direct blow, compression or repeated traction or friction. Although in most cases the diagnosis is obvious, subtle peripheral nerve injuries can be difficult to recognize and, in most cases, require the support of appropriate instrumental evaluations. This review is divided into two parts devoted to the most common upper and lower limb peripheral nerves injuries, the anatomical reasons, the clinical presentation and the most helpful diagnostic tools
Subacute combined degeneration in totally gastrectomized rats: an ultrastructural study
No full textSevere permanent cobalamin (Cbl) deficiency was induced in rats either by total gastrectomy (TG) or through prolonged dietary Cbl deprivation. This paper deals with an ultrastructural investigation of different parts of the central nervous system (CNS) of rats made Cbl-deficient through one of these of two procedures. In both totally gastrectomized (TGX) rats and in rats chronically fed a Cbl-deficient diet, we observed intramyelin edema, with splitting of the lamellae, and interstitial edema affecting the white matter, mainly in the spinal cord (SC). These lesions were also present in the subcortical white matter, although to a lesser degree. In both TGX-rats and in rats chronically fed a Cbl-deficient diet the pyramidal tract and the optic nerve were completely spared. Vascular lesions were never observed. Intramyelin edema and interstitial edema of the white matter account for the patchy myelopathic spongy vacuolation, which is the histological hallmark of human subacute combined degeneration and has been previously seen in SC white matter of TGX-rats. Macro- and micro-glial cells in the white matter were activated, at least as seen ultrastructurally. Interestingly enough, there were activated glial cells even in the gray matter, in which neurons showed absolutely no alterations. Chronic subcutaneous Cbl administration of TGX-rats partially repaired the CNS damage. However, the amelioration produced by this treatment was greater when Cbl was given shortly after TG than when given three and four months after TG, i.e. when the lesions have already been formed
Neuroprotectant drugs in cisplatin neurotoxicity.
No full textCisplatin (CDDP) is one among the most effective and widely used anticancer drugs. Its use is, however, often limited by its peripheral neurotoxicity, which may be severely disabling and sometimes not reversible. To prevent or reduce CDDP peripheral neurotoxicity several "neuroprotective" drugs have been proposed. This goal is of extreme importance in the treatment of cancer patients, especially in view of the better results obtained by anticancer chemotherapy in terms of longer disease-free survival which has made even more crucial than in the past the point of the quality of life of the long-surviving patients. The data of pre-clinical and clinical studies with neuroprotectant agents are often conflicting, in some cases because of inadequate methods of evaluation and/or study design used to examine their effectiveness. The aims of this review will be 1) to discuss and describe the most appropriate methods of evaluation of CDDP and neuro-protectant drugs in experimental in vitro and in vivo pre-clinical studies 2) to evaluate critically the results of the clinical trials reported so far with the combined treatment and 3) to explore the possible future strategies to achieve neuroprotection during high-dose CDDP treatment in humans
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
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