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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.
721

Structure of genes of the L locus in flax controlling resistance to rust / by Md. Rafiqul Islam

Islam, Md. Rafiqul, 1964- January 1986 (has links)
Bibliography: 136-146 / v, 146 leaves, [9] 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. / Thesis (Ph.D.)--Dept. of Agronomy, University of Adelaide, 1987
722

Characterization of pebble : a gene required for cytokinesis in Drosophila melanogaster / by Leanne Michelle Prior.

Prior, Leanne Michelle January 1998 (has links)
Errata is pasted onto back end paper. / Includes bibliographical references (26 leaves). / 115, [68] leaves, [8] 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. / This study entailed work towards the isolation of the pbl gene and preliminary characterisation of a candidate pbl transcript. Plasmid rescue of the genomic DNA flanking the inserted P element led to the isolation of a third candidate p61 cDNA, the 1A cDNA. This data suggests that the IA cDNA is encoded by the p61 gene. / Thesis (Ph.D.)--University of Adelaide, Dept. of Genetics, 1998
723

The structure and genetic control of endosperm proteins in wheat and rye / by Nagendra Kumar Singh

Singh, Nagendra Kumar January 1985 (has links)
Bibliography: leaves [129]-146 / v, 146, [50] leaves, [50] leaves of plates : ill ; 30 cm. / 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 Agronomy, Waite Agricultural Research Institute, 1985
724

Histone gene "knock-out" in mouse embryonic stem cells / by Varaporn Thonglairoam.

Thonglairoam, Varaporn January 1994 (has links)
Bibliography: leaves 113-126. / v, 126, [113] leaves, [10] leaves of plates : ill. ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Studies the biological significance of the mouse Listone variant H2A.Z. Describes the isolation and characterisation of H2A.Z genomic clones from different mouse genomic libraries; H2A.Z gene targeting in mouse E14 embryonic stem cells; and an attempt to generatae ES cell lines and mice which lack the functional H2A.Z protein to investigate H2A.Z function in vitro and in vivo. / Thesis (Ph.D.)--University of Adelaide, Dept. of Biochemistry, 1995?
725

Role of the seed coat in the dormancy of wheat (Triticum aestivum) grains.

Rathjen, Judith Rebecca January 2006 (has links)
Title page, contents and abstract only. The complete thesis in print form is available from the University of Adelaide Library. / Pre-harvest sprouting (PHS) is an important economic problem which affects a significant proportion of the Australian wheat crop through quality downgrading. Grain dormancy is the most effective means of overcoming germination in the wheat spikelet at harvest maturity. It has been a consistent observation over a long period of time that dormant red-grained wheat genotypes are almost more dormant than dormant white-grained genotypes. In white-grained wheat, there are two factors which contribute to dormancy, embryo sensitivity to abscisic acid (ABA) and an interacting and unknown seed coat factor. The proposed dormancy model is that complete dormancy can only be achieved with the coordinate expression of these two factors. This primary objective of this project was to determine the role of this putative seed coat factor in grain dormancy of white-grained wheat."--Abstract. / http://proxy.library.adelaide.edu.au/login?url= http://library.adelaide.edu.au/cgi-bin/Pwebrecon.cgi?BBID=1259900 / Thesis (Ph.D.) -- University of Adelaide, School of Agriculture, Food and Wine, 2006
726

Molecular genetic analysis of preterm labour

Bruiners, Natalie 12 1900 (has links)
Thesis (MSc)--University of Stellenbosch, 2007. / ENGLISH ABSTRACT: The World Health Organisation (WHO) has defined preterm labour as the onset of labour before 37 completed weeks of gestation with an incidence ranging between 5-10%. Although patient care has improved, the rate of preterm birth has slowly been increasing and currently impacts significantly on maternal and fetal mortality and morbidity. The complex condition of preterm labour involves multiple etiologies and risk factors, which complicates the search for candidate markers and / or biomarkers. The aim of this prospective study was to investigate potential genetic associations with preterm labour. The study cohort consisted of consecutive first-time booking, low-risk primigravid pregnant women from a restricted geographical region. The study cohort comprised 421 [306 Coloured and 115 Black] pregnant women presenting at the Paarl Hospital Obstetric clinic. Subsequently, DNA was extracted from whole blood and investigated for a range of known polymorphisms in pro-inflammatory and anti-inflammatory cytokines, as well as the novel LGALS13 gene, for potential variants that may impact on pregnancy outcome. Screening techniques involve combinations of allele-specific PCR amplification, Multiphor SSCP/HD analysis, restriction enzyme analyses and DNA sequencing. A significant association was demonstrated between the IL-1RN*2-allele and adverse pregnancy outcome, mainly in the preterm labour and hypertension group. The presence TNFα-308 A-allele was associated with overall adverse pregnancy outcome and preterm labour. In addition to this, a novel IL-1RN allele was identified in the control group. Mutation screening and subsequent statistical methods revealed an association between a novel LGALS13 exonic variant, 221delT, and preterm labour in Coloured women. Two previouslydocumented intronic variants (IVS2-22A/G and IVS3+72T/A) demonstrated linkage disequilibrium, signifying evolutionary conservation of exon three. Additionally, two novel intronic variants, IVS2-36 G/A and IVS2-15 G/A, demonstrated no association with adverse pregnancy outcome. In this study we identified rare novel exonic variants; two non-synonymous variants in exon three (M44V, [N=2] and K87R, [N=1]) and a silent variant in exon four (P117P, [N=1]) - all identified in individuals from the control cohort. Within coding exon three, an interesting variant [“hotspot”] was identified, which represents six polymorphic bases within an 11bp stretch. No associations were demonstrated with these variants and pregnancy outcome. Furthermore, a previously documented 5' “‘promoter” variant, -98 A/C, was identified and demonstrated no association with adverse pregnancy outcome. However, subdivision of lateonset pre-eclamptic cases revealed a significant association with the A-allele and late-onset preeclampsia. Genotype-phenotype investigation demonstrated association between the IL-10 -1082 A/G, IL-4 C/T and 221delT loci and poor pregnancy progress which manifested as (i) delivery of infants weighing <2000g, (ii) before 37 weeks of gestation. The findings of this study will strengthen our understanding of the pathophysiology underlying pregnancy complications and facilitate the further development of effective treatment strategies to reduce maternal and fetal morbidity and mortality. / AFRIKAANSE OPSOMMING: Die Wêreld Gesondheid Organisasie (WHO) klassifiseer voortydse kraam as kontraksie voor 37 volledige weke, met ‘n insidensie tussen 5-10%. Alhoewel pasiënte-sorg verbeter het, neem die tempo van voortydse geboorte steeds toe, wat ‘n groot impak het op moederstrefte en fetale mortaliteit en morbiditeit. Die komplekse kondisie van voortydse kraam sluit veelvoudige oorsake en risiko faktore in, wat die navorsing van kandidaat en / of biologiese merkers kompliseer. Die doel van hierdie prospektiewe studie, was die potensiële navorsing van genetiese assosiasies met voortydse kraam. Die studie kohort bevat opeenvolgende eerste bespreking van lae risiko primigravida swanger vrouens vanaf ‘n beperkte geografiese omgewing. Die studie kohort beslaan 421 [306 Kleurling en 115 Swart] swanger vrouens teenwoordig by die Paarl Hospitaal Verloskunde kliniek. Vervolgens was DNS geëkstraeer van bloedmonsters en geondersoek vir ‘n verskeidenheid van bekende polimorfismes in pro-inflammatoriese en antiinflammatoriese sitokiene, insluitend die nuwe sifting van die LGALS13 geen potensiaal vir variante wat ‘n impak op swangerskap uitkomste sal hê. Die siftings tegnieke toegepas, sluit in ‘n kombinasie van alleel-spesifieke amplifikasie, Multiphor enkelstring konformasie polimorfisme / heterodupleks analise, restriksie ensiem verterings en volgorde bepalings tegnieke. ‘n Betekenisvolle assosiasie was gedemonstreer tussen die IL-1RN*2-alleel en nadelige swangerskap, beperk tot voortydse kraam en die hipertensie groep. Die teenwoordigheid van die TNFα-308 A-alleel was geassosieer met algehele nadelige uitkomste en voortydse kraam. Daarby, was ‘n nuwe IL-1RN alleel geïdentifiseer in die kontrole groep. Mutasie sifting en opeenvolgende statistiese metodes, het ‘n assosiasie getoon tussen ‘n nuwe LGALS13 koderende variant, 221delT, en voortydse kraam in Kleurling vrouens. Twee voorafbeskryfde introniese variante (IVS2-22 A/G en IVS3+72 T/A), het ‘n betekenisvolle bewys opgelewer dat daar koppelings-onewewig bestaan tussen hierdie variante, en toon evolusionêre konservasie van ekson drie. Addisioneel was twee nuwe introniese variante ontdek, IVS2-36 G/A en IVS2-15 G/A, wat geen assosiasie getoon nie. In hierdie studie het ons ‘n nuwe seldsame koderende variante geïdentifiseer in die kontrole groep, waarvan twee nie-sinonieme variante was in ekson drie (M44V, N=2 en K87R, N=1) en ‘n stil variasie in ekson vier (P117P, N=1). Geleë in die koderende area van ekson drie, was ’n interessante variant [“hotspot’] ontdek, waarvan ses basisse in ‘n 11 basis paar area polimorfies is. Geen assosiasie was getoon met hierdie variante en swangerskap uitkomste nie. Verder was ‘n voorafbeskryfde 5' ‘promotor’ variant, -98 A/C, geïdentifiseer wat geen assosiasie getoon met nadelige swangerskap uitkomste nie. Onderverdeling van laat-aanvangs preeklampsie, het getoon dat die A-alleel ‘n betekenisvolle assosiasie getoon het met die ontwikkeling van laat pre-eklampsie. Genotipe-fenotipe interaksies het ’n assosiasie getoon tussen die IL-10 -1082 A/G, IL-4 C/T en 221delT lokusse en nadelige swangerskap uitkomste, wat manifesteer as (i) kraam van suigelinge wat <2000g weeg, (ii) geboorte voor 37 weke. Die bevindings van hierdie studie sal ons basiese kennis verbeter oor die patologie beskrywend aan swangerskap komplikasies, asook die fasilitering en ontwikkeling van effektiewe behandelings strategieë, om moederstrefte en fetale mortaliteit en morbiditeit te verminder.
727

Analysis of genetic variants in the 5’ regulatory region of the ALAS1 gene in South African patients with Variegate Porphyria (VP)

Du Plessis, Nelita 03 1900 (has links)
Thesis (MSc (Genetics))—University of Stellenbosch, 2007. / The porphyrias are a group of genetic disorders arising from mutations in either one of the final seven genes encoding the haeme synthesis enzymes. These disease-causing mutations lead to an enzyme deficiency that disrupts normal haeme production, resulting in clinical features due to the subsequent accumulation of porphyrin precursors. Like most of the porphyrias, variegate porphyria (VP) is characterized by high inter- and intra- familial clinical variability, with no apparent genotype-phenotype correlation. The delta-aminolevulinate synthase-1 gene (ALAS1) is an apparent candidate gene to explain the variable clinical expression observed in VP, since it encodes the first and rate-determining enzyme of haeme synthesis. Several studies have defined important regulatory elements for the human-, rat- and chicken ALAS1 gene that regulate expression patterns of this gene. It was hypothesized that in VP individuals, variants within/near critical regulatory sites might alter the transcription rate of this gene, and consequently increase/decrease the amount of haeme precursors accumulating as a result of the defective haeme synthesis enzyme. The aim of this study was to identify genetic variants that could influence gene expression in the proximal promoter area of the ALAS1 gene, as well as the two ALAS1-drug responsive enhancer sequences (ADRES) located further upstream. DNA (2133 bp per patient) of 19 clinically defined VP patients was analysed by polymerase chain reaction (PCR) and semiautomated DNA sequencing. Subsequently, in silico analyses using appropriate software programs, and in vitro studies using the luciferase reporter system, were performed to investigate the functionality of the identified variants on ALAS1 gene transcription...
728

Molecular genetic analysis of glucocorticoid-induced thymocyte apoptosis.

Flomerfelt, Francis Andrew. January 1994 (has links)
I have used a molecular genetic approach to study early events in the gene network that precede apoptotic commitment in glucocorticoid-induced thymocyte apoptosis. A panel of recessive, apoptotic-deficient (Apt⁻) mutants were isolated that are cross resistant to several diverse apoptotic treatments. These results indicated that the signal pathways initiated by glucocorticoids, gamma radiation, and c-AMP analog treatment converge to a common apoptotic pathway. Complementation analysis of Apt⁻ cell lines has defined five independent complementation groups that appear to represent mutations in genes that are required for apoptotic commitment. In addition, I have characterized induced gene expression patterns characteristic of dexamethasone (dex)-induced apoptosis and have found that glutathione-s-transferase (GST), Dag8 (a gene of unknown function) and calmodulin (Cam) transcript levels are elevated following dex treatment. Dex-treatment of Apt⁻ cell lines does not change GST or Cam transcript levels which suggests that these cell lines are blocked in early steps of the apoptotic pathway. In contrast, the dominant oncogene, Bcl-2, blocks apoptosis and appears to affect a relatively late event in the apoptotic pathway since the pattern of dex-induced gene expression is normal in cells that express this protein. Since the Apt⁻ cells contain wild type levels of functional glucocorticoid receptor (GR), GST and Cam do not appear to be primary GR target genes, but seem to respond to cellular events that occur prior to apoptotic commitment. In support of this conclusion, it was found that GST transcript levels increase in calcium ionophore-induced apoptotic cells. In contrast, Dag8, transcript levels increased in dex-treated Apt⁻ cells indicating that Dag8 is most likely a primary GR target gene. Furthermore, Dag8 expression was found to be restricted to thymocyte containing tissues and its locus was mapped to the H2 complex of chromosome 17, a region that is known to contain many immunologically important genes. Finally, a model is presented to describe a common apoptotic pathway in murine thymocytes and proposes that an increase in oxidative stress precedes calcium mobilization in response to glucocorticoid treatment.
729

Fluxo lácteo em búfalas (Bubalus bubalis): aspectos ambientais e genéticos

Araujo, Daniele Neves [UNESP] 25 January 2013 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:35:45Z (GMT). No. of bitstreams: 0 Previous issue date: 2013-01-25Bitstream added on 2014-06-13T20:07:26Z : No. of bitstreams: 1 araujo_dn_dr_jabo.pdf: 567500 bytes, checksum: bbf5f199afa8e9062527ea8384197179 (MD5) / Este estudo teve por objetivo analisar quais os fatores ambientais, comportamentais e genéticos que afetam a produção de leite e o fluxo lácteo de búfalas (Bubalus bubalis). Os dados foram coletados durante dois anos em 3 fazendas leiteiras participantes do projeto de controle leiteiro realizado pelo Departamento de Zootecnia da Universidade Estadual Paulista em Jaboticabal, no Estado de São Paulo. No primeiro artigo descreveu-se as médias e as curvas de fluxo lácteo para búfalas e foram estimados parâmetros genéticos para a produção de leite, tempo de ordenha e fluxo lácteo em modelo multicaracterística com inferência bayesiana. No segundo artigo destacou-se a análise da relação de manejo aversivo com reatividade de búfalas na ordenha e os possíveis efeitos desta reatividade sobre as características de produção e rotina de ordenha em búfalas. No terceiro artigo verificou-se a existência de polimorfismos nos genes da ocitocina e do receptor adrenérgico α1A e suas possíveis associações com produção de leite, fluxo lácteo e tempo de ordenha. Os resultados sugeriram que a variação genética da produção de leite, fluxo lácteo e tempo de ordenha são suficientes para efeitos de seleção, sendo que a seleção de uma das características influenciará as outras no mesmo sentido. Observou-se que a reatividade das búfalas e as ações dos retireiros não influenciam as características de produção. E que os polimorfismos encontrados nos genes ocitocina e receptor adrenérgico α1A não se mostram associados às características de produção em búfalas / This study aims to analyze which environmental, behavioral and genetic aspects affect the milk production and milk flow of water buffaloes (Bubalus Bubalis). The data was collected in a period of two years in three dairy farms that were participating in the Dairy Bubaline Test Program developed by the Animal Science Department of São Paulo State University, FCAV, Jaboticabal, SP, Brazil. The first paper described the average and milk flow curves of water buffaloes and genetics parameters were estimated for the milk production, milking speed and milk flow in a multiple-trait analysis with bayesian inference. The second paper highlights an analysis of the relation between the aversive handling with the reactivity of water buffaloes in the milking process and the possible effects of this reactivity on the traits of production and the milking process routine in water buffaloes. The third paper verifies the existence of polymorphisms in the genes of oxytocin and of adrenergic receptor α1A and it's possible associations with milk production, milk flow and milking speed. The results suggest that the genetic variation of the milk production, milk flow and milking speed are sufficient for selection purposes, considering that the selection of one of the characteristics will influence the others in the same way. It was noticed that the reactivity of water buffaloes and the activities of the stockpersons has no influence on the other production characteristics. And also that the polymorphisms found in the genes of oxytocin and of the adrenergic receptor α1A do not show themselves associated to production characteristics in water buffaloes, except for the effect of the α1A over production of protein
730

A study to determine genetic susceptibility to tuberculosis / Kathleen Anne Meehan.

Meehan, Kathleen Anne January 1992 (has links)
Thesis (Masters Diploma (Medical Technology))-- Cape Peninsula University of Technology, 1992 / Studies that document the higher incidence of tuberculosis as well as the variable efficacy of the BCG vaccine in Black, compared to White, populations have alluded to resistance or susceptibility to tuberculosis being genetically controlled.The HIA system has been associated with many diseases involving an immune aetiology. It has been shown that T cell receptor genes have limited restriction fragment length polymorphisrns, serving to create a variation in the repertoire of expressed T cell receptor genes. These repertoire differences may play a fundamental role in disease susceptibility.A study was therefore undertaken to establish whether linkage exists between the HIA system or the T cell receptor genes and a putative susceptibility gene for tuberculosis.Polymorphisrns of these genetic markers were examined in three Cape Coloured multiplex families, affected individuals having culture-positive pulmonary tuberculosis.HLA haplotypes were derived from serological typing of peripheral leucocytes from each individual. B-Iymphoblastoid cell lines were established from each family member. DNA was then extracted and digested with a variety of restriction endonucleases. After gel electrophoresis and Southern blotting, the DNA fragments were probed with a panel of T cell receptor cDNA probes, revealing the allelic polymorphisms.Linkage analysis was done using the Liped computer programme and Lad scores were determined for each marker locus using various genetic models. Haplotypes were also established for the T cell receptor genes and used in the linkage analysis.Although most of the Lad scores fell within the indeterminate range, a cumulative Lod score of 1.79 was obtained from the allele generated by the EcoRV/a2 enzyme/probe combination under a recessive model with 50% penetrance. This represents odds of about 52: 1 in favour of linkage between the T cell receptor a gene and a putative susceptibility gene to tuberculosis.

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