1,720,981 research outputs found

    Generation of a monoclonal antibody to a defined portion of the Helicobacter pylori vacuolating cytotoxin by DNA immunization

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    The capacity of mammalian cells to express proteins encoded by plasmid vectors injected as naked DNA has opened the possibility to induce an immune response against protein antigens by DNA vaccination. We have used DNA immunization to generate a strong antibody response to a defined portion of the Helicobacter pylori vacuolating cytotoxin. A high specific monoclonal antibody has been derived from the splenocytes of an immunized mouse. Our data show that DNA immunization offers the possibility to obtain monoclonal antibodies following a significant shortcut with respect to traditional immunization protocols

    Site-specific monoclonal antibodies against peanut agglutinin (PNA) from Arachis hypogaea. Immunohistochemical study of tissue-cultured cells and of 27 cases of Hodgkin's disease

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    The purpose of this study was to increase the sensitivity of the staining reaction for the T antigen on the surface of neoplastic cells grown in vitro with the use of site-specific monoclonal antibodies (MAbs). The authors describe anti-peanut agglutinin (PNA) MAbs selected by screening the hybridomas with PNA and PNA bound to bovine serum albumin conjugated with the T antigen. The selected hybridomas (F2C8, F3D12, F3A5) were then grown in pristane-sensitized mice or in the Amicon Hollow Fiber System (F2C8). The affinity constant values for PNA were measured, and all the purified MAbs were tested on both native and denatured PNA, wheat germ agglutinin, concanavalin A, and ricin by using the immunoassay dot test and immunoblotting methods. Eleven different cell lines were stained with the three MAbs; similar results were obtained with F2C8 and F3D12. In each case the fluorescence, if present, was associated with the cell membrane, and the intensity of the staining was always stronger when the cells were incubated with the MAbs than when stained with fluorescein-labeled PNA. On the other hand, F3A5 failed to stain unfixed cells preincubated with PNA but stained the same cells after fixation, independently of the presence of PNA. One of the antibodies, F2C8, was used to stain histologic preparations from 27 cases of Hodgkin's disease and was compared with the anti-granulocyte antibody, Leu-M1, which has been used by numerous authors to identify the characteristic Reed-Sternberg cells. The results obtained were qualitatively similar; ie, F2C8 was at least as efficient as anti-Leu-M1 in its ability to stain the typical diagnostic cells in Hodgkin's disease

    Going Beyond Counting First Authors in Author Co-citation Analysis

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    The 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

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    “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

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    We 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

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    We 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

    Author Index

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    Sjogren's syndrome and Helicobacter pylori infection

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    Objective: To determine whether Helicobacter pylori infection is associated with primary Sjogren's syndrome. Patients and methods: Four patients with Sjogren's syndrome underwent endoscopy. Three H. pylori culture-positive patients were treated with triple therapy for eradication of infection. One patient was not infected and was not treated. Eradication was verified endoscopically and/or serologically 2 and 6 months after the end of therapy. The severity of xerophthalmia and xerostomia was evaluated clinically and by the Shirmer's test before, and 2 and 6 months after the end of therapy. Results: H. pylori was eradicated from the three infected patients. The signs and symptoms of Sjogren's syndrome improved in all three patients. The Shirmer's test confirmed amelioration. Conclusion: H. pylori may trigger or worsen the symptoms of Sjogren's syndrome

    koamabayili/VECTRON-author-checklist: VECTRON author checklist

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    We 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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