1,720,959 research outputs found
A new solid-phase immunoradiometric assay for anti-thyroglobulin autoantibody
No full textA newly developed sensitive and quantitative immunoradiometric assay (IRMA) for anti-thyroglobulin (anti-Tg) autoantibody is described. Serum samples to be tested are added to wells of polyvinyl microtiter plates coated with human thyroglobulin. After removal of the unbound material, anti-Tg antibody is determined by adding purified 125I-anti-human immunoglobulin G antibody. Using 1.0 microliter of serum anti-Tg antibody was detected in 81.2% of patients with Hashimoto's thyroiditis or idiopathic myxedema (n = 32), in 46.4% of those with Graves' disease (n = 28), in 11.9% of subjects with other thyroid disorders (n = 42) and in 4.2% of normal controls (n = 71). Similar percentages of positive tests were observed by passive hemagglutination (PH) and a good correlation was found between the antibody levels determined by the two techniques. Using larger amounts of serum (100 microliters) detectable anti-Tg antibody by IRMA was found in the majority of patients with thyroid autoimmune disorders who had negative PH tests. Quantitative measurements of anti-Tg antibody by IRMA could be obtained by using purified anti-Tg antibody as standard reference. The minimum detectable amount of anti-Tg antibody was 0.5 ng. The present method is proposed as a simple and convenient technique for quantitative measurement of any antibody, using wells coated with the appropriate antigen
A new solid-phase immunoradiometric assay for antithyroid microsomal antibody
No full textA new sensitive, quantitative, and specific immunoradiometric assay (IRMA) for antithyroid microsomal (anti-M) antibody has been developed. Samples to be tested are incubated within wells of polyvinyl microtiter plates coated with solubilized thyroid microsomal antigen. After removal of unbound material, anti-M antibody is detected by adding purified [125I]antihuman immunoglobulin G (IgG) antibody. Using 1.0 microliter serum, anti-M antibody was found by IRMA in all of the patients with Hashimoto's thyroiditis or idiopathic myxedema (n = 19), in 86% of those with Graves' disease (n = 42), in 10.9% of subjects with other nonautoimmune thyroid disorders (n = 37), and in 8.4% of normal controls (n = 71). A good correlation was found with the results obtained in anti-M antibody tests by passive hemagglutination. Using larger volumes of serum (up to 100 microliters), anti-M antibody detectable by IRMA was found in some patients with Graves' disease and negative passive hemagglutination tests. Quantitative measurements of anti-M antibody by IRMA could be performed using a standard IgG preparation containing high levels of anti-M antibody. The minimal detectable amount ranged between 1-2 ng IgG, corresponding to a sensitivity 15-30 times greater than that of the competitive binding radioassay. We suggest that the present IRMA may be proposed as a general technique for the detection of different organ-specific autoantibodies
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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