1,720,997 research outputs found
Protective effect of arabic gum against cardiotoxicity induced by doxorubicin in mice: A possible mechanism of protection
No full textTitle: Protective effect of arabic gum against cardiotoxicity induced by doxorubicin in mice: A possible mechanism of protection
Author(s): Abd-Allah, ARA, Al-Majed, AA, Mostafa, AM, Al-Shabanah, OA, El Din, AG, Nagi, MN
Source: JOURNAL OF BIOCHEMICAL AND MOLECULAR TOXICOLOGY Volume: 16 Issue: 5 Pages: 254-259 Published: 2002
Department: Pharmacology and Toxicology
Abstract: Arabic gum (AG) is a naturally occurring compound that has been proposed to posses potent antioxidant activity. In this study, the possible effects whereby AG could protect against cardiotoxicity induced by doxorubicin (DOX) in mice were carried out. Administration of single dose of DOX (15 mg/kg, i.p.) induced cardiotoxicity 72 h, manifested biochemically by a significant elevation of serum creatine kinase (CK) (EC 2.7.3.2). In addition, cardiotoxicity was further confirmed by the significant increase in lipid peroxides measured as malondialdehyde (MDA). Administration of AG (25 g/kg) orally for 5 days before and 72 h after DOX injection produced a significant protection against cardiotoxicity induced by DOX. This was evidenced by significant reductions in serum CK and cardiac lipid peroxides. The effect of AG was examined on the superoxide anion radical generated by enzymatic and nonenzymatic methods. The results indicate that AG is a potent superoxide scavenger. The superoxide scavenging effect of AG may explain, at least in part, the protective effect of AG against cardiotoxicity induced by DOX. (C) 2002 Wiley Periodicals, Inc
Studies on the reproductive, cytological and biochemical toxicity of Ginkgo biloba in Swiss albino mice
No full textTitle: Studies on the reproductive, cytological and biochemical toxicity of Ginkgo biloba in Swiss albino mice
Author(s): Al-Yahya AA (Al-Yahya, Abdulaziz A.), Al-Majed AA (Al-Majed, Abdulhakeem A.), Al-Bekairi AM (Al-Bekairi, A. M.), Al-Shabanah OA (Al-Shabanah, O. A.), Qureshi S (Qureshi, S.)
Source: JOURNAL OF ETHNOPHARMACOLOGY Volume: 107 Issue: 2 Pages: 222-228 Published: SEP 19 2006
Department: Pharmacology and Toxicology
Abstract: Ginkgo biloba (an herbal product), used as a folkloric medicine in the treatment of dementia, was evaluated for its effects on reproductive, cytological and biochemical toxicity in male Swiss albino mice. The mice were treated with different doses (25, 50 and 100 mg/kg/day) of the aqueous suspension of Ginkgo biloba for 90 days by oral gavage. The following parameters were evaluated: (1) reproductive organ weight; (2) motility and content of sperms; (3) spermatozoa morphology; (4) cytology of the testes chromosomes; (5) study on reproduction; (6) biochemical study on proteins, nucleic acids, malondialdehyde (MDA) and nonprotein sulfhydryl (NP-SH). The treatment caused significant changes in the weight of caudae epididymis, prostate, chromosomal aberrations, rate of pregnancy and pre-implantation loss. However, the percent motility, sperm count and morphology of spermatozoa were not affected. Our study on biochemical parameters showed depletion of nucleic acids, NP-SH and increase of MDA, which elucidated the role of free radical species in the induced changes in testis chromosomes and the reproductive function. The exact mechanism is not known, however, the activation of GABA, glycine and glutamate under the influence of Ginkgo biloba and its constituents might have generated free radicals and depleted cellular glutathione by calcium influx and membrane depolarization. The observed toxicity is attributed to the toxic constituents (ginkgolic acids, biflavones, cardanols, cardols, bilobalides and quercetin) of Ginkgo biloba. Our results warrant careful use of Ginkgo biloba as a remedy for impotence and/or erectile dysfunction. (c) 2006 Elsevier Ireland Ltd. All rights reserved
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
Title: A derivatization reagent for vigabatrin and gabapentin in HPLC with fluorescence detection
No full textA validated, selective, and sensitive chromatographic method for determination of two antiepileptic drugs, vigabatrin (VGA) and gabapentin (GBA) has been developed. Determination was obtained by pre-column reaction of the samples with fluorescamine and separating the corresponding derivatives with a reverse phase HPLC on a 5 micro ASMT BANsil CN column and fluorescence detection (lambda(ex) 390 nm, lambda(em) 472 mn). Acetonitrile-TBAH (20: 80) containing phosphoric acid was used as mobile phase. A linear quantitative response curve was generated over a concentration range of 0.2-1.0 mu g/mL with a correlation coefficient of 0.999 and 0.995 for vigabatrin and gabapentin, respectively. The percentage recovery of vigabatrin from spiked plasma was 102.7 with RSD% of 4.51. Validation of accuracy and precision were satisfactory for both drugs within-and between-run assay. The method is specific for the intact drugs, and can be adopted in the presence of possible interferences
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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