1,721,058 research outputs found
Self-induced water intoxication : a case report
Get PDFCITATION: Emsley, R. A. & Taljaard, J. J. F. 1988. Self-induced water intoxication : a case report. South African Medical Journal, 74:80-81.The original publication is available at http://www.samj.org.zaA 19-year-old female schizophrenic with self-induced water intoxication is described. Factors of pathogenic significance included primary polydipsia and non-maximal urinary diluting capacity.Publisher’s versio
Catechol oestrogens
Get PDFThe original publication is available at http://www.samj.org.zaCITATION: Neethling, A. C. & Taljaard, J. J. F. 1980. Katesjolestrogene. South African Medical Journal, 58:495-497.Hydroxylation of oestrogens in the 2 or 4 positions leads to the formation of catechol oestrogens. These compounds are physiologically active in animals, especially in the control of gonadotropin secretion. Physiological activity can be ascribed to either an oestrogenic action or interaction with the catecholaminergic systems. These compounds are also formed in human subjects. Surprisingly high levels are found in the urine. The peri-ovulatory peak in urinary catechol oestrogen excretion is compatible with a role for these compounds in the control of gonadotropin secretion.Publisher’s versio
The β-adrenoceptor and endocrine abnormalities in juvenile depression
No full textCITATION: Carstens, M. E., Taljaard, J. J. F. & Van Zyl, A. M. 1990. The β-adrenoceptor and endocrine abnormalities in juvenile depression. South African Medical Journal, 77:360-363.The original publication is available at http://www.samj.org.zaNeuro-endocrine disturbances were determined in juvenile depressives and possible correlations with biochemical abnormalities investigated. It was established that, as in adult depressives, the young also showed a high incidence of cortisol non-suppression after dexamethasone administration. In addition, a positive correlation observed between lymphocyte β-adrenoceptor maximal number of binding sites and basal cortisol levels stresses the involvement of the noradrenergic neurotransmission system.Publisher’s versio
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe 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
Get PDF“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
Get PDFWe 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
Get PDFWe 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
An investigation into the mechanism of delta-aminolaevulinic acid neurotoxicity
No full textThe original publication is available at http://www.samj.org.zaCITATION: Taljaard, J. J. F., Lamm, M. C. L. & Truter, L. 1981. 'n Ondersoek na die meganisme van delta-aminolevuliniensuur-neurotoksisiteit. South African Medical Journal, 60:180-183.The neurotoxicity of δ-aminolaevulinic acid (ALA), porphobilinogen (PBG), glutamic acid, γ-aminobutyric acid and kainic acid was compared in order to investigate the possibility of a common neurotoxic mechanism. Only ALA (10 μM) and glutamic acid (1 mM) were toxic towards neurons in culture, as measured by cell survival after 5 days' exposure. 3H-kainic acid binds to striatal membranes with an equilibrium dissociation constant (KD) of 57 nM and the number of binding sites was found to be 20 pmol/g striatal tissue. However, neither of the porphyrin precursors could displace kainic acid from these binding sites. Kainic acid alone caused neuronal degeneration after intrastriatal administration, as determined by 3H-spiroperidol binding to striatal membranes. The porphyrin precursors ALA and PBG thus do not share a common neurotoxic mechanism with the well-known neurotoxin kainic acid.Publisher’s versio
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