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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.
171

Molecular evolution of hepatitis C virus quasispecies.

Oon, Aileen, Biotechnology & Biomolecular Sciences, Faculty of Science, UNSW January 2007 (has links)
The viral dynamics of the hepatitis C virus (HCV) in newly acquired infection are not well understood. HCV exists within an individual as a spectrum of minor variants termed quasispecies. The evolution of minor variants may contribute to viral escape of the host?s immune response, thereby facilitating development of chronic infection. The hypervariable 1 region (HVR1) is the most heterogeneous part of the HCV genome and contains a putative B-cell epitope. Thus, diversity in HVR1 could be a strategy used to evade neutralising antibodies. Acutely infected individuals (n=24) were examined with the aim of defining HVR1 quasispecies diversity in acute infection. The characterisation of the E1/HVR1 sequence and host specific evolution of HCV minor variants in treatment nonresponders was also investigated. HCV E1/HVR1 fragments were amplified from 48 sera using a combined reverse transcription-polymerase chain reaction (RT-PCR). Products were TA cloned into pCRIITOPO and approximately 10-20 clones were sequenced from each sample. HVR1 quasispecies diversity was examined longitudinally via sequence analysis. Quasispecies diversity was characterised primarily by mean nucleotide diversity. The mean HVR1 diversity of the acute cohort (n=48; 2.12% ?? 2.22) was lower than the diversity obtained for a cohort of chronically infected individuals (n=99; 4.5% ?? 5.1). There was no significant difference in mean HVR1 diversity between the HIV/HCV co-infected and HCV mono-infected groups (p=0.99) or between the clearer and non-clearer groups (p=0.85). Examination of amino acid usage and the hydropathic profile of each position in HVR1 revealed that sequence variation was confined to specific sites. The investigation of host specific evolution of HVR1 quasispecies demonstrated that minor variants (comprising 10- 20% of a population) became the dominant species over time in two treatment non-responders. These variants bore mutations that were not reflected in the consensus sequence of their respective populations at the initial timepoint analysed. Common infection was identified by 98% HVR1 sequence homology within two pairs of individuals. The evolution of common strains appeared to be different between individuals, suggesting host pressures may influence quasispecies evolution. This thesis provided an insight into the viral dynamics and host specific evolution of acute phase quasispecies.
172

Behaviour and ecology of the primary parasitoids Cotesia urabae and Dolichogenidia eucalypti (Hymenoptera: Braconidae) and their host Uraba lugens (Lepidoptera: Noctuidae) / by Geoffrey Rowland Allen.

Allen, Geoffrey Rowland January 1989 (has links)
Includes bibliography. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (Ph.D.)--University of Adelaide, Dept. of Entomology, 1989
173

Immune reactions involved in parasitoid-host interactions / Dongmei Li.

Li, Dongmei January 2002 (has links)
Bibliography: leaves 113-144. / ix, 144 leaves, [56] leaves of plates : ill. (some col.) ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Investigates the functions of the maternal, protein secretions of the endoparasitoid wasps Venturia canescens Gravenhorst regarding their role in providing protection against the host's immune system. Also investigates mucinous protein secretions on the egg surface and coagulation reactions and their role in protecting eggs against host cellular attacks. / Thesis (Ph.D.)--University of Adelaide, Dept. of Applied & Molecular Ecology, 2002
174

The role of polymorphonuclear cells in immunity to Nematospiroides dubius infections in mice /

Penttila, Irmeli. January 1984 (has links) (PDF)
Thesis (Ph. D.)--University of Adelaide, Dept. of Microbiology and Immunology, 1984. / Includes bibliographical references (leaves 113-128).
175

Preference and performance of the water lily aphid (Rhopalosiphum nymphaeae) among native and invasive duckweeds (Lemnaceae)

Storey, Melissa Cameron. January 2007 (has links) (PDF)
Thesis (M.S.)--Georgia Southern University, 2007. / "A thesis submitted to the Graduate Faculty of Georgia Southern University in partial fulfillment of the requirements for the degree Master of Science." In Biology, under the direction of Alan Harvey. ETD. Electronic version approved: July 2007. Includes bibliographical references (p. 59-64) and appendices.
176

Identification of fish hosts for wild populations of rare freshwater mussels (Lampsilis cariosa and Leptodea ochracea) using a molecular DNA key /

Kneeland, Stephen C. January 2006 (has links) (PDF)
Thesis (M.S.) in Ecology and Environmental Science--University of Maine, 2006. / Includes vita. Includes bibliographical references (leaves 71-75).
177

Behaviour and ecology of the primary parasitoids Cotesia urabae and Dolichogenidia eucalypti (Hymenoptera: Braconidae) and their host Uraba lugens (Lepidoptera: Noctuidae) /

Allen, Geoffrey Rowland. January 1989 (has links) (PDF)
Thesis (Ph.D) -- University of Adelaide, Dept. of Entomology, 1989. / Includes bibliography.
178

Studies on the systematics of the cestodes infecting the emu, Dromaius novaehollandiae (Latham, 1790) /

O'Callaghan, Michael George. January 2004 (has links) (PDF)
Thesis (Ph.D.)--University of Adelaide, School of Earth and Environmental Sciences, Discipline of Environmental Biology, 2004. / Includes bibliographical references (leaves 219-236).
179

Novel inducible phytochemical defences against plant parasitic nematodes /

Soriano, Imelda Rizalina. January 2004 (has links) (PDF)
Thesis (Ph.D.)--University of Adelaide, School of Agriculture and Wine, Discipline of Plant and Pest Science, 2004. / "August 2004" Bibliography: leaves 146-169.
180

Histological observations on the development of Ceratomyxa shasta actinosporeans in the polychaete host, Manayunkia speciosa /

Meaders, Marlene D. January 1900 (has links)
Thesis (M.S.)--Humboldt State University, 2008. / Includes bibliographical references (leaves 66-69). Also available via Humboldt Digital Scholar.

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