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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.
1

The study of genetic variation in trees using the random amplified polymorphic DNA (RAPD) technique

Allnutt, Theodore Richard January 1996 (has links)
No description available.
2

Isoenzymic studies in apples and pears

Chouliaras, Vassilios January 1997 (has links)
No description available.
3

Functional genomics in fish: towards understanding stress and immune responses at a molecular level

Ribas Cabezas, Laia 10 July 2006 (has links)
Aquesta tesis doctoral està basada en estudiar la resposta immunològica dels peixos en models d'estrès i d'activació del sistema immune des la genòmica funcional. L'aplicació de tecnologies moleculars com el Differential Display van permetre identificar y clonar por primera vegada en orades (Sparus aurata) y en altres especies de peix, el gen enolasa. Aquest enzim glucolític s'ha plantejat per primera vegada com un bon marcador molecular per estudiar el benestar dels peixos. Per mitjà de l'ús d'una plataforma de microarrays dissenyada específicament per a salmònids, i altres metodologies biomoleculars, es va comprovar que els nivells d'enolasa eren regulats en diferents teixits y en diferents especies de peix, com també en adverses situacions per l'animal. D'altra banda, s'han estudiat diferents gens immunològics candidats a ser possibles gens per l'estudi del sistema immunològic dels peixos. Aquests gens s'han estudiat a nivell d'expressió en teixits de truites (Oncorhynchus mykiss) mitjançant PCR convencional i PCR quantitativa, i l'ús de metodologies biomoleculars i bioinformàtiques. Entre ells, destaca el factor de transcripció PU.1, un gen indispensable per el desenvolupament de l'hematopoesi. Aquest gen, s'ha clonat i caracteritzat per primera vegada en salmònids. L'expressió de PU.1 s'ha estudiat mitjançant l'ús d'hibridacions in situ en ronyó anterior y en cervell de truita. A més, l'ús de microarray en aquest dos teixits han permès fer un estudi exhaustiu i pioner a nivell de transcriptòmica en peixos. Les anàlisis del xip de microarray, ha revelat que grups de gens s'activen o s'inhibeixen com a conseqüència d'un estrès immunològic.En resum, aquesta tesis doctoral ha aplicat el desenvolupament de noves tecnologies moleculars pioneres en peixos, com el microarray, la clonació de noves seqüències gèniques i la bioinformàtica, per estudiar la genòmica funcional dels peixos en situacions d'activació dels mecanismes d'estrès i del sistema immune. / The main results of the present thesis can be integrated to a better understanding the stress and the immune responses in fish at a transcriptional level. The application of functional genomic tools, which encloses from using simple PCR analysis to more modern, sophisticate and fashionable microarray technique, allowed us to identified transcriptional regulations of certain set of genes which are enhanced or repressed under stress conditions. Our findings contribute to increase knowledge of molecular mechanism involved in coping the stress and immune responses in fish and provides a better understanding of fish physiology when fish health is threatened. Furthermore, thesis results may be interesting for aquaculture which looks for good biomolecular markers that may improve fish production and fish quality. The isolation, characterization and gene expression study with further microarray analysis of the enolase gene, allowed us to describe enolase as a possible biomolecular marker to determine fish welfare. The in situ hybridization study of the hematopoietic transcription factor PU.1, contributed to amplify the knowledge of the development of the fish immune system. Throughout this thesis, DNA sequences and mRNA expression levels of several genes studied, have contributed to enlarged genomic fish database. In summary, this thesis described from a transcriptional level, gene expression and molecular mechanisms activated or repressed when fish welfare is threatened and contributes to a better understanding of transcriptiomic mechanisms required to cope with the stress.
4

Population genetic structure of Faidherbia albida (Del.) A. Chev. (Leguminosae, Mimosoideae)

Rendell, Sarah January 1998 (has links)
No description available.
5

Molecular markers of recombinant CHO DG44 cell phenotype changes during prolonged culture

Juniarsih, Imelda January 2015 (has links)
The increasing demand for recombinant therapeutic proteins coupled with advances in technologies allow research to develop approaches to improve the efficiency, yield, and quality of biopharmaceutical products from CHO cells. CHO DG44 cells used in this study were engineered to express erythropoeitin (EPO) as the model recombinant protein in a DHFR-based selection system. From a series of CHO-DG44 cell lines derived from a polyclonal population, one cell line expressed a notable change in growth phenotype during prolonged culture (10 weeks). This cell line (IJ4) exhibited prolonged growth, reached a greater density, and delayed cell death. The change in growth was reflected in an increased total yield of EPO, whilst the specific productivity of cell line IJ4 remained similar. The increased total yield of EPO presents a desirable goal for production and hence detailed ‘omics studies were performed to identify factors associated with better cell growth and survivability. Two different ‘omics analyses were performed (microarray transcriptomic and GC-MS metabolic profiling) to identify potential target genes and key metabolites associated with changes in growth profile. The -omics analyses identified a subset of genes (MMP20, PLA1A, POSTN, SLC46A3, and TOP2A), and a metabolic marker (farnesal) strongly associated with changes in cell growth and nutrient uptake. The use of complementary ‘omics approaches to identify molecular markers has allowed an integrated model to be built, which explains how CHO cell phenotype can adapt to long-term culture, and this defines molecular approaches for cell line screening and engineering.
6

Polimorfismos no gene Tfam e características de carcaça em novilhas da raça Nelore

Ayres, Denise Rocha [UNESP] 29 July 2008 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:26:07Z (GMT). No. of bitstreams: 0 Previous issue date: 2008-07-29Bitstream added on 2014-06-13T19:33:21Z : No. of bitstreams: 1 ayres_dr_me_jabo.pdf: 301436 bytes, checksum: 880c0c14e46f06bc104b475866c16dcf (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / O fator de transcrição mitocondrial A (gene Tfam), uma proteína fundamental para a ocorrência do processo de transcrição mitocondrial e um participante na replicação do genoma dessa organela, atua indiretamente na biogênese e oxidação de lipídeos. O objetivo do presente estudo foi de caracterizar e verificar a relação entre polimorfismos na região promotora do gene Tfam com características de carcaça em novilhas Nelore. Foram analisadas 272 novilhas da raça Nelore pertencentes a três rebanhos experimentais da Estação Experimental de Zootecnia de Sertãozinho – (EEZS), unidade de pesquisa do Instituto de Zootecnia, dois deles selecionados (NeS e NeT) para peso ao ano (machos) e ao sobreano (fêmeas) e um rebanho controle (NeC), em que os animais são selecionados para a média desses pesos. O DNA genômico foi extraído a partir do sangue dos animais, seguindo-se a amplificação do fragmento analisado e posterior digestão com enzimas de restrição. As medidas de gordura de cobertura foram obtidas por ultra-sonografia entre 555 e 800 dias de idade. Pela análise de PCR-RFLP-Hae III foi observada a presença de três genótipos (AA, CA e CC) e, pela análise de PCR-RFLP-Mbo I foram observados apenas dois genótipos (CC e TC). Não houve associação significativa entre os polimorfismos observados no gene Tfam, com as enzimas Hae III e Mbo l, e a característica espessura de gordura de cobertura. Entretanto, os resultados sugerem uma associação entre o polimorfismo detectado pela enzima Hae III e a área do músculo Longissimus dorsi. / The mitochondrial transcription factor A (Tfam) is an essential protein for the transcription and genome replication processes of this organelle which also has indirect effects on lipids biosynthesis and oxidation. This study was conducted on intent to verify the existence of polymorphisms on the promoter region of Tfam gene and verify their possible relationships with carcass traits from Nelore heifers (Bos indicus). Genomic DNA were extracted from blood samples of 272 animals followed by PCR isolation/amplification of Tfam gene and application of the RFLP with thr restriction enzymes Hae III and Mbo I. The carcass traits considered were rib eye and fat thickness and were obtained by ultrasound between the ages of 555 and 800 days. The analysis with PCR-RFLP Hae III and Mbo I showed the migration patterns AA, CA, CC and CC,TC, respectively. There was no significant association among the patterns obtained and the fat thickness. However, the results showed an associated effect among the patterns obtained with PCR-RFLP Hae III and rib eye, which indicates the possible use of Tfam as a candidate gene.
7

Polimorfismos no gene Tfam e características de carcaça em novilhas da raça Nelore /

Ayres, Denise Rocha. January 2008 (has links)
Resumo: O fator de transcrição mitocondrial A (gene Tfam), uma proteína fundamental para a ocorrência do processo de transcrição mitocondrial e um participante na replicação do genoma dessa organela, atua indiretamente na biogênese e oxidação de lipídeos. O objetivo do presente estudo foi de caracterizar e verificar a relação entre polimorfismos na região promotora do gene Tfam com características de carcaça em novilhas Nelore. Foram analisadas 272 novilhas da raça Nelore pertencentes a três rebanhos experimentais da Estação Experimental de Zootecnia de Sertãozinho - (EEZS), unidade de pesquisa do Instituto de Zootecnia, dois deles selecionados (NeS e NeT) para peso ao ano (machos) e ao sobreano (fêmeas) e um rebanho controle (NeC), em que os animais são selecionados para a média desses pesos. O DNA genômico foi extraído a partir do sangue dos animais, seguindo-se a amplificação do fragmento analisado e posterior digestão com enzimas de restrição. As medidas de gordura de cobertura foram obtidas por ultra-sonografia entre 555 e 800 dias de idade. Pela análise de PCR-RFLP-Hae III foi observada a presença de três genótipos (AA, CA e CC) e, pela análise de PCR-RFLP-Mbo I foram observados apenas dois genótipos (CC e TC). Não houve associação significativa entre os polimorfismos observados no gene Tfam, com as enzimas Hae III e Mbo l, e a característica espessura de gordura de cobertura. Entretanto, os resultados sugerem uma associação entre o polimorfismo detectado pela enzima Hae III e a área do músculo Longissimus dorsi. / Abstract: The mitochondrial transcription factor A (Tfam) is an essential protein for the transcription and genome replication processes of this organelle which also has indirect effects on lipids biosynthesis and oxidation. This study was conducted on intent to verify the existence of polymorphisms on the promoter region of Tfam gene and verify their possible relationships with carcass traits from Nelore heifers (Bos indicus). Genomic DNA were extracted from blood samples of 272 animals followed by PCR isolation/amplification of Tfam gene and application of the RFLP with thr restriction enzymes Hae III and Mbo I. The carcass traits considered were rib eye and fat thickness and were obtained by ultrasound between the ages of 555 and 800 days. The analysis with PCR-RFLP Hae III and Mbo I showed the migration patterns AA, CA, CC and CC,TC, respectively. There was no significant association among the patterns obtained and the fat thickness. However, the results showed an associated effect among the patterns obtained with PCR-RFLP Hae III and rib eye, which indicates the possible use of Tfam as a candidate gene. / Orientadora: Lúcia Galvão de Albuquerque / Coorientadora: Maria Eugênia Zerlotti Mercadante / Banca: Humberto Tonhati / Banca: Antonio Roberto Otaviano / Mestre
8

Artificial Selection and the Genome: A Deep Pedigree Analysis of an Elite Soybean Cultivar

Grainger, Christopher 20 August 2012 (has links)
The objective of this thesis was to investigate the genomic changes that have occurred due to the effects of long-term artificial selection applied by soybean breeders. A total of 42 cultivars from six different breeding programs, comprising the multi-generational pedigree of OAC Bayfield were genotyped with molecular markers and chromosomal inheritance was tracked throughout the pedigree. The graphical genotype profile of the 20 chromosomes revealed substantial allelic structure that has been built up in certain chromosomes, in the form of specific linkage blocks, which have been conservatively inherited. A selective sweep analysis using microsatellite markers was performed using the members of OAC Bayfield’s pedigree to identify genomic regions that have retained a molecular selective signature through OAC Bayfield in the varieties derived from it. Overall, there was a high level of agreement between the identified quantitative trait loci (QTL) and the phenotypic traits that would have been expected to be under breeders’ selection.
9

Characterization of colon cancer cell culture based screening assay to study effects of phenolic acids

2011 September 1900 (has links)
In Canada, colorectal cancer is the second leading cause of death from cancer in men and the third leading cause of death from cancer in women. Several factors contribute to the development of cancer. Genetic predisposition, diet, and lifestyle habits are some of the major factors for colorectal cancer development. In the diet related factors, epidemiological studies suggest that consumption of whole grains rich in dietary fiber are associated with low incidence of human colon cancer. Recent studies have also shown that, in addition to dietary fiber, the type of dietary fiber and other compounds such as phenolic acids present in cereal grain bran may also have a role to play in colon cancer prevention. In a recent study, eleven major phenolic acids which differed in anti-oxidant activity were identified in wheat bran from wheat varieties belonging to six different market classes. The main objective of this study was to develop an in vitro cell culture based assay system to study the effect of phenolic acids on colon cancer development. Another objective was to study the effect of phenolic acids on selected molecular markers associated with cell proliferation, apoptosis and inflammation. Two well established colon carcinoma cell lines HT-29 and HCT 116 were treated with varying concentrations of fourteen phenolic acids to study their effect on cell survival and proliferation. In addition, immunohistochemical assays were performed on treated cells for two cell proliferation markers (Cyclin D1 and Ki67), an apoptosis marker (Bax) and three inflammatory markers (Beta-catenin, COX-2 and iNOS). Treatment of phenolic acids inhibited the growth of both the cell lines, however the effects varied with phenolic acid and cell line used in the assay. As determined by IC50, the growth of HCT 116 cells was inhibited the most by caffeic, ellagic, and gallic acids with IC50 of 0.22 mM, 0.17 mM, and 0.15 mM, respectively. On the other hand, caffeic, chlorogenic, and gallic acids are most effective in preventing the growth of HT-29 cells, with IC50 at 0.06 mM, 0.28 mM, and 0.30 mM, respectively. Immunohistochemical and Western Blotting studies revealed that phenolic acids differentially affected markers for cell proliferation, apoptosis and cell inflammation. In most of the cases, phenolic acid treatments up-regulated the pro-apoptosis marker Bax, while it down-regulated cell proliferation marker Cyclin D1. The results clearly show that a cell culture based assay can be used to study the effect of phenolic acids or other chemical constituents isolated from plants to study their effect on colon cancer cell lines. Statistical analysis revealed that only in very limited cases, results of molecular markers correlated to cell growth and proliferation. Therefore, to draw firm conclusions, more detailed and extensive studied need to be completed using different phenolic acids, the two cell lines and more replications. However, this study has developed the necessary protocols and provided some indicative results such as most of the phenolic acids induced pro-apoptosis pathway in both the colon cancer lines. Future studies with extracted phenolic acids from wheat bran using the cell culture system optimized in this study can be used to define the role of different wheat varieties in colon cancer prevention.
10

COMPARATIVE ANALYSIS OF SOYBEAN (GLYCINE MAX) ACCESSIONS USING INTER SIMPLE SEQUENCE REPEAT (ISSR) AND RANDOM AMPLIFIED POLYMORPHIC DNA (RAPD) MARKERS

Alamri, Sarah 16 May 2014 (has links)
Soybean (Glycine max) is an important crop in the world in terms of total production and usage. It is also among the least diverse species. The main objectives of the present study were 1) to determine differences between ISSR and RAPD marker systems in detecting genetic variation in soybeans and 2) to identify and characterize accession- diagnostic molecular markers in G. max accessions. Genomic DNAs from 108 G. max accessions from 11 different gene pools were analyzed using several ISSR and RAPD primers. The levels of polymorphic loci detected with the two marker systems were in general moderate and similar.. Overall, 82% of genetic distance values were above 0.40 based on ISSR analysis. However, RAPD data revealed that the accessions from different countries are closely related with 64% genetic distance values below 0.40. The dendrograms constructed with ISSR data revealed that the South Korean accessions formed an out-group while the RAPD analysis showed that accessions from Sweden were separate from the other 10 gene pools. One variety-diagnostic marker generated with ISSR 5 primer was identified in the accession Kao Chien Tao from China. This marker was cloned, and sequenced. Although RAPD and ISSR marker systems detected similar levels of genetic variability, they target different regions of the soybean genome, resulting in different clustering of the 11 gene pools indicating different genetic relatedness among them. This finding demonstrates the usefulness of both marker systems in assessing diversity and relatedness among Glycine max gene pools.

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