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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
41

Evaluation of a Monoclonal-based EIA for the Detection of Giardia lamblia and the Identification of the Antigen

Boone, James Hunter M.S. 18 May 1998 (has links)
I. A number of commercial enzyme immunoassay (EIA) tests are available for the diagnosis of giardiasis. In a time of rising health-care costs, there is a need for diagnostic tests that are rapid, specific, sensitive and inexpensive. In the first phase of this study, I developed a monoclonal-based EIA, the GIARDIA TEST, with these qualities in mind. This assay's performance characteristics were determined by a comparison study using conventional ova and parasite examination, immunofluorescence antibody test (IFA) and other commercial EIA tests. Studies were done in-house at TechLab, Inc. and at various U.S. medical facilities. Results were statistically analyzed to determine sensitivity (ability of the assay to detect a positive result), specificity (amount of cross-reactivity), predictive positive value (the confidence in a positive result), predictive negative value (the confidence in a negative result) and overall correlation with the reference assay. II. There remain many questions to be answered about the various antigens produced by Giardia lamblia and how they can be utilized as diagnostic markers. In the second phase of this study, I identified and partially characterized the antigen (Ct7 Ag) that reacts with the Ct7 monoclonal antibody (MAb). This MAb is an IgM class mouse immunoglobin that is utilized by the GIARDIA TEST and by an immunofluorence antibody test (IFA) which detects Giardia cysts in water and feces. The results of this study will provide physicians and researchers with detailed information about the Ct7 Ag and why it is a useful marker for giardiasis. / Master of Science
42

SYSTEM CONTROL AND INTEGRATION OF STAND ALONE MICROFLUIDIC SYSTEMS

Nagendran, Preethy January 2000 (has links)
No description available.
43

Immuntechnologische Verfahren zum Aufbau homogener Immunoassays sowie zur Selektion Antikörper produzierender Zellen / Immunotechnological procedures for the development of homogeneous immunoassays and the selection of antibody producing cells

Sellrie, Frank January 2007 (has links)
Homogene Immunoassays sind immunologische Testverfahren, bei deren Durchführung vollständig auf Separations- und Waschschritte verzichtet werden kann. Der Substrate Channeling Immunoassay beruht auf der Weitergabe eines Substrates in einem immunologischen Komplex aus zwei Enzymen. Das Produkt des ersten Enzyms dient dem zweiten Enzym als Substrat zur Generierung eines photometrisch nachweisbaren Produktes. Voraussetzung für diese Weitergabe ist die enge räumliche Nähe beider Enzyme. Diese Nähe wird durch eine Bindung zwischen Analyt und anti-Analyt Antikörper vermittelt. Ein solcher Substrate Channeling Immunoassay wurde unter Verwendung der Enzyme Glucoseoxidase und Peroxidase aufgebaut. Das so etablierte System war funktionstüchtig, jedoch blieb seine Sensitivität hinter der normaler, heterogener Immunoassays zurück. Die Grundlage eines Fluorescence Quenching Immunoassays ist der gegenseitige Ausschluß zweier Antikörper bei der Bindung eines Dihapten-Konjugates. Das Konjugat besteht dabei aus dem Analyten und einem Fluorophor. Die beiden um die Konjugatbindung konkurrierenden Antikörper sind ein anti-Analyt Antikörper und ein anti-Fluorophor Antikörper, der zudem über die Eigenschaft verfügt, bei Bindung des Fluorophors dessen Fluoreszenz zu löschen. Externe Gaben des freien Analyten verschieben das eingestellte Gleichgewicht in Richtung Fluorophor-Bindung und damit Fluoreszenz-Löschung. Die Änderung der Fluoreszenz ist direkt an die Konzentration des freien Analyten gekoppelt und dient zu deren Bestimmung. Ein solcher Fluorescence Quenching Immunoassays wurde für die Konzentrationsbestimmung des Herbizides Diuron etabliert. Die erreichten Sensitivitäten erlauben die praktische, immundiagnostische Anwendung des Systems. Ein Dihapten-Konjugat wurde ebenfalls zum Aufbau eines Verfahrens zur Selektion Antikörper produzierender Zellen eingesetzt. Die Selektion der Antikörper produzierenden Zellen erfolgt unter Verwendung eines Toxinkonjugates. Dieses Konjugat besteht aus einem Liganden und einem Toxin. Die Antikörperbindung des Liganden behindert sterisch die Wechselwirkung der Toxinkomponente im Konjugat mit deren Zielstruktur in oder auf der Zelle. Nur Zellen die einen geeigneten Antikörper sezernieren, überleben die Selektion und reichern sich in der Kultur an. Das Selektionsverfahren wurde erfolgreich für die Selektion von E.coli Zellen eingesetzt, die einen rekombinanten, Fluorescein bindenden Antikörper produzierten. Das hierfür synthetisierte Toxinkonjugat bestand aus Fluorescein (Ligand) und Ampicillin (Toxinkomponente). Eine Ablösung der bisher für diese Aufgabe gebräuchlichen, außerordentlich kostenintensiven, Screening Methoden wird damit möglich. / Homogeneous immunoassays are test systems which do not depend on separation steps. The substrate channeling immunoassay is based on the product/substrate transfer in an immunological complex built up by two enzymes. The product of the first enzyme functions as substrate for the second enzyme. The second enzyme generates a photometrically detectable product. The close proximity of these two enzymes is the basis of the substrate channeling. This proximity is created by antibody binding to the corresponding analyte. The enzymes glucose oxidase and peroxidase were used for the development of such an assay system. The established homogeneous immunoassay was functional. But the sensitivity of the assay was much lower than that of conventional heterogeneous immunoassays. The principle of a fluorescence quenching immunoassay is based on the fact that two antibodies exclude each other from binding to a dihapten conjugate. The conjugate consists of the analyte and the fluorophore. The two antibodies which compete for the conjugate binding are an anti-analyte antibody and an anti-fluorophore antibody. This anti-fluorophore antibody quenches the fluorescence of the fluorophore after binding. The addition of free analyte alters the equilibrium of the system so that the anti-fluorophore antibody is bound to the fluorophore and the fluorescence is quenched. The change in fluorescence is therefore an indicator of the concentration of free analyte added. A homogeneous fluorescence quenching immunoassay was established for the determination of the herbicide diuron. The sensitivities obtained allow the practical immunodiagnostic application of the system. A dihapten conjugate was also employed for the development of a selection method for antibody-producing cells. Toxin conjugates were used in this system. Each conjugate consisted of a ligand and a toxin. Antibody binding to the ligand sterically inhibits the toxin component to interact with its target structure. Only cells secreting a binding antibody will survive the selection and will accumulate in culture. The system was applied to the selection of E.coli cells producing a recombinant fluorescein-binding antibody. The toxin conjugate used in experiment consisted of fluorescein (ligand) and ampicillin (toxin component). This selection procedure allowed the isolation of recombinant antibody-producing E.coli cells. It has the potential to replace the time-consuming and labour-intensive methods used so far.
44

Determination of microbial proteinases using thin layer enzyme assays

Wikström, Maude. January 1983 (has links)
Thesis (doctoral)--University of Göteborg, 1983. / Extra t.p. with thesis statement inserted. Includes the author's five published papers. Includes bibliographical references.
45

Determination of microbial proteinases using thin layer enzyme assays

Wikström, Maude. January 1983 (has links)
Thesis (doctoral)--University of Göteborg, 1983. / Extra t.p. with thesis statement inserted. Includes the author's five published papers. Includes bibliographical references.
46

Flow injection ELISA a system for immunochemical on-line quantitation of proteins in biotechnological samples /

Nilsson, Mats. January 1994 (has links)
Thesis (doctoral)--Lund University, 1994.
47

Flow injection ELISA a system for immunochemical on-line quantitation of proteins in biotechnological samples /

Nilsson, Mats. January 1994 (has links)
Thesis (doctoral)--Lund University, 1994.
48

Biosensors based on capacitance measurement

Ball, Mark January 1997 (has links)
No description available.
49

The preparation and application of monoclonal antibodies specific for phosphorylated isoforms of myelin basic protein

Yon, Suzanne Michele January 1995 (has links)
No description available.
50

The contribution of steroids to the digoxin-like immunoreactive substance in coral blood.

January 1989 (has links)
Wong, Shun-yun. / Thesis (M.Sc.)--Chinese University of Hong Kong, 1989. / Bibliography: leaves 76-79.

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