1,720,958 research outputs found
Selenium enhances glutathione peroxidase activity and prostacyclin release in ultured human endothelial cells. Concurrent effects on mRNA levels
No full textSelenium (Se) is an essential component of glutathione peroxidase (GSH-Px), an enzyme that protects cells by reducing intracellular peroxides. Impaired Se status and GSH-Px activity seem associated with increased risk of atherosclerotic vascular diseases. This study reports the effects of Se supplementation on GSH-Px activity, on prostacyclin (PGI2) production, on 12-hydroxy-eicosatetraenoic acid (12-HETE) levels, and on GSH-Px mRNA expression in cultured human umbilical vein endothelial cells (HUVEC). Se-enriched HUVEC showed significant increase of both GSH-Px activity and thrombin-stimulated production of PGI2 in the presence of stable concentrations of 12-HETE. On the other hand, an inverse correlation between Se concentrations in culture media and GSH-Px mRNA levels in Northern blot analysis was shown; this suggests that a major degree of regulation for GSH-Px expression by Se is most likely exerted at the posttranscriptional level. These observations may help to explain the increased incidence of atherosclerosis described in Se-deficient individuals
Serum levels of soluble CD30 are elevated in the majority of untreated patients with Hodgkin's disease and correlate with clinical features and prognosis
No full textPURPOSE: To evaluate the serum levels of the soluble form of the CD30 molecule (sCD30) in patients with Hodgkin's disease (HD) to establish whether there is a correlation with clinical features at presentation and prognosis.
PATIENTS AND METHODS:
The sCD30 serum levels of 117 patients were measured at diagnosis with a commercial sandwich enzyme-linked immunoadsorbent assay (ELISA) test kit, and in 78 of these patients the sCD30 levels were also recorded during the follow-up period.
RESULTS:
sCD30 levels at diagnosis were increased (> 20 U/mL) in a high proportion of patients (87.2%; mean +/- SD, 108 +/- 134 v 5.3 +/- 5.7 U/mL in controls, P < .0001) and correlated with stage (stages I + II, 73 +/- 97 U/mL; III + IV, 162 +/- 165 U/mL; P < .0001), with presence of B symptoms (stage A, 69 +/- 82 U/mL; stage B, 162 +/- 171 U/mL; P < .0001), and, to some extent, with tumor burden (bulky presentation, 141 +/- 129 U/mL; nonbulky, 91 +/- 133 U/mL; P = .058). Patients with sCD30 levels greater than 100 U/mL at diagnosis had a significantly higher rate of poor outcome in terms of failure to achieve a complete remission (CR) or disease relapse after CR achievement. In fact, the event-free survival (EFS) duration of patients with sCD30 levels greater than 100 U/mL was significantly worse (P = .0016). Using multivariate analysis, an sCD30 level greater than 100 U/mL retained its significance after adjustment for other prognostic parameters.
CONCLUSION:
sCD30 in HD at presentation strictly correlates with clinical features. Serum levels greater than 100 U/mL at diagnosis entail a significantly higher risk of treatment failure, a factor that is independent of other prognostic parameters
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
ICAM-1 tissue overexpression associated with increased serum levels of its soluble form in Hodgkin's disease.
No full textAppropriate 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
- …
