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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.
11

Phylogenetics and molecular identification of the Ochlerotatus communis and Oc. punctor complexes (Diptera: Culicidae)

Hosseinzadeh Namin, Hooman 10 September 2013 (has links)
Accurate identification of pathogens and vectors is essential in epidemiological studies of mosquito-borne pathogens. However, the members of the communis and punctor complexes are difficult to distinguish because they are highly cryptic species, with little to no species-specific morphological characters. The objective of this thesis is to develop molecular tools, including RFLP and DNA barcoding using cytochrome oxidase I (COI), internal transcribed spacer 2 (ITS2) and the intron of ribosomal protein S12 (RPS12) to facilitate identification of the members of these two complexes in Manitoba. A distinct interspecific distance for COI was found between the members of the communis complex included here, and diagnostic RFLP profiles were developed for Oc. communis and Oc. churchillensis. Relatively low average interspecific genetic distances using COI, ITS2 and RPS12 were observed between the members of the punctor complex, indicates no discernable boundaries between these species based on DNA barcoding.
12

The effect of hydrogen on soil bacterial communities

Osborne, Catherine Anne January 2007 (has links)
Most legume-nodulating rhizobia release hydrogen into the surrounding soil. The effect of hydrogen on soil bacterial communities in microcosms and surrounding legume roots was investigated by generating Terminal Restriction Fragment Length Polymorphism (T-RFLP) profiles of bacterial 16S rRNA genes. (For complete abstract open document).
13

Une nouvelle classe de séquences d'ADN mobile chez mycobacterium avium ssp.paratuberculosis : utilisation pour le typage moléculaire et l'analyse fine de la régulation génétique. / No title available

Thibault, Virginie 22 October 2008 (has links)
Introduction : Mycobacterium avium ssp. paratuberculosis (Map) est l’agent étiologique de la paratuberculose, qui affecte les ruminants et est suspectée d’être transmissible à l’homme en lien avec la maladie de Crohn, une inflammation chronique de l’intestin. Le contrôle de cette maladie à forte prévalence, nécessite de mieux identifier et connaître son agent. Aujourd’hui, le typage des souches repose sur la RFLP-IS900 qui est peu discriminante et peu sensible. Objectif : Dans cette optique, mon projet de thèse a eu pour objectif de développer une méthode de typage moléculaire novatrice utilisant les minisatellites afin d’évaluer le degré de diversité génétique de la sous-espèce paratuberculosis. Ce travail nécessite la construction d’une collection de souches et le développement d’une méthode de typage hautement discriminante. Résultats : Nos résultats obtenus avec huit marqueurs MIRU-VNTR (Mycobacterial Interspersed Repetitive Unit-Variable Number Tandem Repeat) montrent que cette méthode est rapide, adaptée à Map et plus discriminante de la RFLP-IS900. Par ailleurs, ces mêmes marqueurs nous ont permis de typer une collection de souches de M. avium ssp. avium et M. avium ssp. hominissuis. Le typage MIRU-VNTR a également permis de différencier la souche vaccinale Map 316F, en fonction de son origine, laboratoire Weybridge (Royaume-Uni) et laboratoire Mérial (France). Dans le but d’affiner la discrimination de ces souches, nous nous sommes intéressés aux marqueurs microsatellites SSR (Short Sequence Repeat) analysés par séquençage. Onze loci SSR ont été analysés et évalués sur une collection de 127 souches de Map préalablement typées par MIRU-VNTR et RFLP- IS900. Les résultats suggèrent que la stratégie la plus adaptée pour la discrimination des souches consiste à utiliser dans un premier temps le typage MIRU-VNTR ; le typage SSR et la RFLP-IS900 peuvent permettre une discrimination complémentaire. Conclusion : Ce travail de thèse nous a permis de développer une méthode de typage rapide, fiable et discriminante pour l’étude de la sous-espèce paratuberculosis, mais également du complexe MAC. / Background: Mycobacterium avium subsp. paratuberculosis (Map) is the etiological agent of paratuberculosis, affecting wide range of domestic ruminants and suspected to be involved in Crohn’s disease in human. The control of this disease, highly prevalent, requires better identification methods and better knowledge of the etiological agent. Currently, the gold standard method to type Map strains is the IS900-RFLP. But this technique is not very sensitive and not very discriminating. Objective: In this context, the project of my thesis aimed to develop an innovative method of molecular typing using the minisatellites in order to evaluate the degree of diversity of Map. This work requires the construction of a collection of strains and the development of a new molecular typing method. Results: Our results obtained with eight MIRU-VNTR markers (Mycobacterial Interspersed Repetitive Unit-Variable Number Tandem Repeat) show that MIRU-VNTR typing is a fast typing method, adapted to Map and more discriminative than IS900-RFLP. In addition, these 8 markers could be applied to type a collection of Mycobacterium avium subsp. avium and Mycobacterium avium subsp. hominissuis. MIRU-VNTR typing differentiated the vaccine strain 316F according to the laboratory of origin Weybridge (UK) or Mérial (France). In order to improve the discrimination of the strains, we used the microsatellites markers SSR (Short Sequence Repeat) using sequencing analysis of the Map genome. Eleven SSR were analysed and evaluated on a collection of 127 Map strains previously typed by MIRU-VNTR and IS900-RFLP typing. Our results suggested that the most adapted strategy to discriminate the Map strains consisted in using MIRU-VNTR typing, and that SSR and RFLP-IS900 typing to better discriminate the clustered isolates. Conclusion: The work of my thesis enabled to develop fast, reliable and robust typing method for the study of Map and also MAC subspecies.
14

Detecção da diversidade molecular de Candida spp. isoladas de UTI neonatal

Arraes, Ana Carolina Palmeira 10 June 2013 (has links)
Submitted by Hiolanda Rêgo (hiolandar@gmail.com) on 2013-06-10T20:55:35Z No. of bitstreams: 1 Dissertação_ICS_ Ana Carolina Arraes.pdf: 1876812 bytes, checksum: c4740a70b3675be50d2ebafeb0ba8fe3 (MD5) / Made available in DSpace on 2013-06-10T20:55:35Z (GMT). No. of bitstreams: 1 Dissertação_ICS_ Ana Carolina Arraes.pdf: 1876812 bytes, checksum: c4740a70b3675be50d2ebafeb0ba8fe3 (MD5) / CAPES / A incidência de candidemia tem aumentado nos últimos anos e o espectro das espécies de Candida tem mudado com a emergência das espécies não-albicans e com o aumento da resistência antifúngica. A técnica de PCR associada à análise dos polimorfismos de fragmentos de restrição (PCR-RFLP) e AP-PCR são exemplos de técnicas moleculares utilizadas para a detecção da variabilidade genética desses micro-organismos. O objetivo deste trabalho foi caracterizar molecularmente Candida spp. clinicamente importantes. Foram estudadas 82 leveduras do gênero Candida, 73 isolados clínicos e nove cepas padrão de referência da “American Type Culture Collection” (ATCC). O DNA genômico foi extraído através de lise mecânica/química e fenol-clorofórmio. Após amplificação com iniciadores ITS1 e ITS4, os produtos da PCR foram digeridos com as enzimas DdeI, HaeIII, BfaI e MspI. Outra amplificação foi realizada com o iniciador arbitrário AP-4. A identificação fenotípica revelou a frequência de 38% de C. parapsilosis, 33% de C. albicans, 27,5% de C. tropicalis e 1,5% de C. guilliermondii. Após amplificação, foi possível identificar e diferenciar as espécies C. lusitaniae, C. guilliermondii, C. famata e C. glabrata. A diferenciação entre C. albicans, C. dubliniensis C. tropicalis, C. krusei e C. parapsilosis não foi bem evidenciada com as enzimas DdeI e HaeIII. Porém, MspI conseguiu diferenciar C. tropicalis, C. krusei, C. parapsilosis, C. glabrata, C. guilliermondii, C. lusitaniae e C. famata, juntamente com BfaI que separou C. albicans de C. dubliniensis. Já a técnica de AP-PCR com o iniciador AP-4, possibilitou a distinção das nove espécies cepas padrão ATCC de Candida, pois todas apresentaram perfis de amplificação com número, intensidade e tamanho de banda específico, onde cada espécie foi alocada em grupo distinto e a relação de similaridade variou de 38-69%, ratificando o poder de diferenciação das espécies. As técnicas moleculares foram reprodutíveis e relativamente rápidas, de fácil interpretação e podem ser aplicadas na identificação de espécies clinicamente importantes de Candida para auxílio no diagnóstico mais rápido e tratamento mais eficiente. / Salvador
15

ESTUDO SOBRE CARACTERÍSTICAS GENÉTICAS DE Mycobacterium tuberculosis ISOLADO DE PACIENTES COM E SEM LESÕES CAVITÁRIAS.

VINHAS, S. A. 30 August 2013 (has links)
Made available in DSpace on 2016-08-29T15:35:05Z (GMT). No. of bitstreams: 1 tese_6777_Tese SAV 04-10-13.pdf: 4494409 bytes, checksum: 06e58e07b25332ca734da704af738a2c (MD5) Previous issue date: 2013-08-30 / Introdução: Baseado na hipótese de que a variabilidade genética de Mycobacterium tuberculosis (MTB) pode influenciar a virulência e a gravidade da doença os perfis genéticos de isolados clínicos de MTB foram avaliados para detectar associação entre diversidade genética e gravidade da doença. Objetivos: Analisar características genéticas de isolados de MTB e verificar sua possível associação com a gravidade da TB pulmonar. Métodos: Estudo retrospectivo, caso controle, conduzido em Vitória-ES, utilizando isolados de MTB (2003 a 2006, n=214) de pacientes com TB pulmonar, cavitária (127) e não cavitária (87). Realizou-se genotipagem por meio de RFLP-IS6110, Spoligotyping, MIRU-VNTR 24 loci, e a análise de deleções e inserções, como RDRio, RD174 utilizando PCR multiplex, bem como a detecção do Ag85C103. Realizou-se análise estatística, para verificação dos padrões de distribuição das variáveis, seguida de análises bivariadas para verificação de associações entre elas, empregando-se os teste exato de Fisher ou Chi-quadrado, ambos com 95% de intervalo de confiança e nível de significância (&#61554;) < 0,05. Resultados: Após a regressão logística, as variáveis que contribuíram no modelo explicativo da doença foram baciloscopia (ORajust = 5,96; IC= 2,58-13,73) e produção de escarro (ORajust = 4,55; IC= 1,28-16,12). Não houve associação estatisticamente significativa com o restante das variáveis.A família LAM foi a mais frequente entre os dois grupos analisados, representando 65 (62%) dos isolados no grupo cavitário e 40 isolados (38%) do grupo não cavitário. Não houve diferença estatisticamente significativa entre os grupos em relação à deleção RDRio (p=0,65) e com relação à deleção RD174 (p=0,65). Dentre os 205 isolados analisados, 25 (12%) isolados do grupo não cavitário e 43 (21%) do grupo cavitário, estavam em cluster. não houve diferença estatisticamente significativa entre a quantidade de clusters e os grupos analisados (p= 0,4). Conclusões: Foi determinado o perfil genotípico dos isolados de pacientes com doença pulmonar, cavitária e não cavitária. Não houve associação entre a presença de cavidade e os genótipos encontrados. Não houve associação do genótipo com nenhum dos marcadores moleculares avaliados. Palavras Chaves: Mycobacterium tuberculosis, genotipagem molecular, RFLP- IS6110, MIRU-VNTR 24 loci , Spoligotyping.
16

Studium historického rozšíření linií pstruha obecného v ČR a na Slovensku pomocí vybraných znaků mitochondriální DNA / Study of historical expansion of brown trout lineages in the Czech republic and in Slovakia republic with using mtDNA markers.

JAŠKOVÁ, Iva January 2009 (has links)
The brown trout (Salmo trutta) is an ecologically, economically, aesthetically fish species whose poor conservation status in the European countries calls for further attention and action. The continuing erosion of the genetic resources of brown trout populations by human activities calls for strategies to reverse the current trend. We studied a genetic diversity of population of brown trout in the territory of Czech R. and in Slovakia using genetic markers. In the fragments of mitochondrial DNA (gen for ND-5/6) and nuclear DNA (gen for LDH1) amplified through PCR the differences were searched with the use of RFLP. In tested populations seven haplotypes were founded, four haplotypes were represented in almost of all populations. The ``Danubian haplotypes{\crqq} were strictly confined to the Danubian and Vistula drainages, the ``Atlantic haplotypes{\crqq} dominated in all populations, most of the total molecular variance (72 %) was attributed to differences within populations. Two alleles at LDHC1&#1645; - the ancestral &#1645;100 and &#1645;90 (at a high frequency) were revealed. This genotypic replacement is considered to be due to anthropogenic activities.
17

Identifikace kvasinek rodu Saccharomyces z listů, bobulí a moštu révy vinné / Identification of yeasts genus Saccharomyces from leaves, grapes and must of grape-vine.

Škodová, Anna January 2008 (has links)
This diploma thesis is concerned about the PCR-RFLP method for identification of yeasts genus Saccharomyces from leaves, grapes and must of white wine. The thesis describes an obtaining of pure cultures of yeasts, isolation DNA and amplification of specific segments of DNA using PCR method. Splitting of this segments by restriction endonukleases and a detection of final fragments by zone electrophoresis are mentioned too. Length of fragments and numbers of restriction fragments, which are characteristic of every species, enable a determination of microorganisms and their inclusion into the system. The basic informations on yeasts and molecular methods for their identification are named in the theoretical part of the thesis. The main part of the thesis deals with the processing of grapes of grape-wine and the manufacturing of white wine.
18

Výběr vhodných autochtonních kvasinek pro výrobu vína / Selection of appropriate indigenous yeasts for wine production

Krátká, Veronika January 2014 (has links)
The aim of this diploma thesis was the selection of appropriate indigenous yeasts for wine production. Tested yeasts were isolated from the grapes from the winery Maňák Žádovice. The yeasts isolated within theses in 2009 – 2012 have been also tested, and commercial wine yeast have been tested for comparison. In the theoretical part the focus is on the technology of wine, in particular fermentation. The work is also focused on yeasts metabolism and taxonomy. There was described the principle of PCR-RFLP, and methods used to characterize the properties of isolated yeasts. In the experimental part was made isolation of yeasts, theirs identification using PCR-RFLP and to select the most suitable yeast in wine making proces were performed physiological tests.
19

Sledování vlivu použité autochtonní kultury kvasinek na kvasný proces výroby vína / Monitoring of the influence of indigenous culture of yeasts on the fermentation process of making wine

Michálek, Petr January 2015 (has links)
This thesis deals with the identification of wine yeasts isolated from the grape must using PCR-RFLP method. The yeasts were isolated from Pinot Noir grape variety must. Grapes were grown and produced in accordance with the requirements placed on organic and integrated farming. Samples were processed in the laboratory, where pure cultures of individual yeast were obtained. A commercial kit was used for yeast DNA isolation. Obtained DNA was used for further analysis. Using the polymerase chain reaction and the primers ITS1 and ITS4 a specific segment of 5.8S rDNA-ITS region was amplified. The PCR products were then detected by electrophoresis in an agarose gel, and after a subsequent purification, three restriction enzymes: HaeIII, HinfI and HhaI were subjected to restriction analysis. The DNA was digested to fragments specific for yeast species and they were detected by agarose electrophoresis. Similarity of these isolates was compared using BioNumerics program and the result is dendrogram of genetic similarity of isolated yeast. The basic chemical analysis of samples must was also performed.
20

Izolace a identifikace kvasinek z vinice pro jejich možné využití k výrobě vína / Isolation and identification of yeasts from the vineyard to their possible utilisation in wine making

Fialová, Lenka January 2016 (has links)
The aim of this work was to isolate the Saccharomyces cerevisiae yeast from the surface of wine grapes of the Malverina and Sauvignon varieties. Isolated yeasts were identified by the PCR-RFLP method. 5,8S ITS rDNA was amplified using PCR and restricition endonucleases HaeIII, HhaI, HinfI and TaqI were used for the restriction analysis which followed. The results were processed by UPGMA cluster analysis using the BioNumerics programme. The dominant genus on the surface of the Malverina variety grapes was Brettanomyces/Dekkera, while on the surface of the Sauvignon grapes we found mainly yeasts of the Pichia genus. The Saccharomyces cerevisiae species was not isolated from any of the two grape varieties.

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