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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.
21

ANNOTATION OF WHITEFLY EXPRESSED SEQUENCE TAGS AND VALIDATION OF GENES WITH POTENTIAL SIGNIFICANCE TO BEGOMOVIRUS TRANSMISSION

Saripalli, Chandrasekhar January 2008 (has links)
The whitefly Bemisia tabaci (Gennadius) (Hemiptera) complex is the sole arthropod vector of the genus, Begomovirus (family, Geminiviridae), which causes debilitating diseases of plants, worldwide. Virus-vector specificity is conferred through co-evolved, whitefly vector-viral capsid protein-protein interactions. Membrane-bound receptors are thought to facilitate virion passage across the gut-hemolymph and hemolymph-salivary gland interfaces, and virion circulation is expected to elicit innate defense and stress-related proteins. Our goal was to select and validate genes involved in whitefly-mediated transmission. Whitefly expressed sequence tags (ESTs) from a previous study were re-annotated, taking advantage of newly available insect EST, UniGene, and Protein sequences. Six whitefly genes and transcripts, actin, cyclophilin, GBLP, GAPDH 3, knottin, and whitefly endosymbiont HSP60, representing three gene ontology (GO) categories, were analyzed using PCR or RT- PCR, respectively, followed by cloning and DNA sequencing. Analysis confirmed the presence of all six whitefly genes and five transcripts, with the knottin transcript being undetectable.
22

A genetic analysis of the French Canadian population in search of evidence in favour of novel breast cancer susceptibility genes

Oros Klein, Kathleen. January 1900 (has links)
Thesis (Ph.D.). / Written for the Dept. of Human Genetics. Title from title page of PDF (viewed 2009/06/10). Includes bibliographical references.
23

Lymphoid specific elements deregulate c-myc transcription following chromosomal translocation in murine plasmacytoma and human Burkitt's lymphoma cells /

Madisen, Linda. January 1996 (has links)
Thesis (Ph. D.)--University of Washington, 1996. / Vita. Includes bibliographical references (leaves [85]-98).
24

Avaliação dos genes MLL, RB e TP53 em pacientes com síndrome mielodisplásica / Evaluation of genes MLL, RB and TP53 in patients with Myelodysplastic Syndromes

Lima, Diego Silva January 2011 (has links)
LIMA, Diego Silva. Avaliação dos genes MLL, RB e TP53 em pacientes com síndrome mielodisplásica. 2011. 95 f. Dissertação (Mestrado em Patologia) - Universidade Federal do Ceará. Faculdade de Medicina, Fortaleza, 2011. / Submitted by denise santos (denise.santos@ufc.br) on 2013-12-03T12:56:53Z No. of bitstreams: 1 2011_dis_dslima.pdf: 4024143 bytes, checksum: 0a18d4cb329d542975fac3641f5bbd03 (MD5) / Approved for entry into archive by denise santos(denise.santos@ufc.br) on 2013-12-03T12:59:05Z (GMT) No. of bitstreams: 1 2011_dis_dslima.pdf: 4024143 bytes, checksum: 0a18d4cb329d542975fac3641f5bbd03 (MD5) / Made available in DSpace on 2013-12-03T12:59:05Z (GMT). No. of bitstreams: 1 2011_dis_dslima.pdf: 4024143 bytes, checksum: 0a18d4cb329d542975fac3641f5bbd03 (MD5) Previous issue date: 2011 / Myelodysplastic syndromes (MDS) represent a heterogeneous group of clonal disorders affecting the hematopoietic pluripotent cell, characterized by low cell counts in peripheral blood, dysplasia in one or more cell lines, inefficient hematopoiesis and increased risk of progression to acute myeloid leukemia. Although the disease can affect patients of other age groups, they are more frequent in those with advanced age with an average 60 to 75 years at diagnosis. Chromosomal abnormalities are observed in approximately 50% of all cases of MDS and are related with clinical and morphological findings. The aim of this study was to determine, through the technique of FISH (fluorescence in situ hybridization), the frequency of changes involving the MLL, RB, and TP53 genes in patients with MDS and associate these changes with cytogenetic findings. The cases included in the study were selected in the ambulatory of SMD from University Hospital Walter Cantídio. Thirty three patients were selected, 17 had aged over 60 years. 52% of patients were classified, according to WHO criteria, as refractory cytopenia with dysplasia in multiple lineages (RCDM) and 61% stratified, according to IPSS, as intermediate risk 1 (INT-1). 78% of patients had abnormalities detected by cytogenetics, among them 31% had complex karyotypes (more than 3 changes per metaphase). 18% of patients had changes at least in one of the three genes valued in this study by FISH. Three patients showed alterations of TP53 gene, being detected in two patients (records 31 and 6) the deletion of a single allele or both alleles of the gene, respectively, and in the third (record 2), we detected amplification of TP53 gene, all this changes were not detected by classical cytogenetics, because it is a less sensitive technique. 6% of patients (records 7 and 22) had rearrangement of MLL gene. In the first case, FISH discarded the gene deletion alleged by cytogenetic, proving that it was present in the genome of the patient, but in a rearranged form, and in the second case cytogenetics failed to demonstrate rearrangement of the gene. For the RB gene, FISH identified only one patient (3%) with deletion of one allele of the gene, and this change was also not detected by classical cytogenetics. During evaluating the TP53 gene, FISH allowed identification of two patients (records 5 and 10) presenting at least six extra copies of chromosome 17, probably representing a small hyperdiploid clone partially detected in the first patient and not detected in the second . In the six patients who showed abnormalities of the genes analyzed, FISH has provided information that added, changed or confirmed the result previously given by classical cytogenetics, which are a major application of this technique due to its high sensitivity compared to the traditional method. / As síndromes mielodisplásicas (SMD) representam um grupo heterogêneo de doenças clonais que acometem a célula precursora hematopoética pluripotente, caracterizando-se por baixa contagem de células no sangue periférico, displasia em uma ou mais linhagens celulares, hematopoese ineficiente, além do risco aumentado de progressão para leucemia mielóide aguda. Embora a doença possa acometer pacientes de outras faixas etárias, é mais frequente naqueles com idade avançada, com média ao diagnóstico de 60 a 75 anos. As anormalidades cromossômicas são observadas em aproximadamente 50% de todos os casos de SMD, estando, em alguns casos, relacionadas com achados clínicos e morfológicos. O objetivo deste trabalho foi determinar, através da técnica de FISH (hibridização in situ por fluorescência), a frequência de alterações envolvendo os genes MLL, RB e TP53 em pacientes com SMD e associar estas alterações com os achados citogenéticos. Os casos inseridos no estudo foram oriundos do ambulatório de SMD do Hospital Universitário Walter Cantídio. Dos 33 pacientes selecionados, 17 pertenciam ao grupo com idade acima de 60 anos. 52% dos pacientes foram classificados, segundo a OMS, como citopenia refratária com displasia em múltiplas linhagens (CRDM) e 61% estratificados, segundo o IPSS, como de risco intermediário 1 (INT-1). Um total de 78% dos pacientes apresentaram alterações citogenéticas, dentre eles 31% possuíam cariótipos complexos (mais de 3 alterações por metáfase). A técnica de FISH permitiu identificar em 18% dos pacientes alterações envolvendo um dos três genes avaliados. Três pacientes apresentaram alteração do gene TP53, sendo detectada em dois deles (registros 31 e 6) a deleção de um único alelo ou de ambos os alelos do gene, respectivamente, e no terceiro (registro 2), detectou-se a amplificação do gene TP53, sendo estas alterações não visualizadas através da citogenética clássica, por se tratar de um técnica menos sensível. Detectou-se em 6% dos pacientes (registros 7 e 22) rearranjo do gene MLL, no primeiro a FISH descartou a suposta deleção do gene alegada pela citogenética, provando que o mesmo estava presente no genoma do paciente, porém de forma rearranjada e no segundo a citogenética não conseguiu demonstrar o rearranjo do gene. Quanto ao gene RB, a FISH permitiu identificar apenas um paciente (3%) com deleção de um dos alelos do gene, sendo esta alteração também não detectada pela citogenética clássica. A FISH possibilitou identificar, durante a avaliação do gene TP53, dois pacientes (registros 5 e 10) apresentando pelo menos 6 cópias extras do cromossomo 17, devendo essa alteração se tratar de um pequeno clone hiperdiplóide detectado parcialmente no primeiro paciente e não detectado no segundo. Nos seis pacientes que apresentaram alteração dos genes avaliados, a FISH proveu informações que adicionaram, confirmaram ou alteraram o resultado previamente emitido pela citogenética clássica, sendo estas uma das principais aplicações desta técnica devido sua alta sensibilidade quando comparada ao método clássico.
25

Caracterização molecular dosistema de grupo sanguineo Dombrock em uma população brasileira / Molecular analysis of Dombrock blood grou'p system in brazilian people

Baleotti Junior, Wilson 29 May 2006 (has links)
Orientador : Lilian Maria de Castilho / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Ciencias Medicas / Made available in DSpace on 2018-08-06T19:52:19Z (GMT). No. of bitstreams: 1 BaleottiJunior_Wilson_D.pdf: 8406610 bytes, checksum: 54b8f3febe199a21fce361b234c634e8 (MD5) Previous issue date: 2006 / Resumo: O sistema de grupo sangüíneo Dombrock é constituído por um par de antígenos antitéticos, Doa e Dob, e três antígenos de alta freqüência populacional, Gregory (Gya), Holley (Hy) e Joseph (Joa). O gene DO, que codifica os antígenos do sistema Dombrock, foi recentemente clonado e suas bases moleculares foram elucidadas. Os antígenos Doa e Dob. são controlados pelos alelos DOA e DOB que estão associados à troca de três nucíeotídeos no exon 2 do gene DO: 378C/T, 624T/C e 793A/G, respectivamente. O fenótipo Jo(a-) está associado com a substituição 350C/T que caracteriza o alelo JO. O fenótipo Hy-negativo está associado à presença de um dos alelos: HY1 ou HY2. O alelo HY2 é caracterizado pela substituição 323G/T. Uma substituição adicional 898C/G, no exon 3, caracteriza o gene HY/1. Recentemente dois novos alelos foram descritos: DOB- SH (378C, 624C, 793G) e DOA-HA (378T, 624T, 793A). Considerando que: as bases moleculares dos antígenos Dombrock foram elucidadas; que novos alelos têm sido descritos; a miscigenação da população brasileira e que até o momento nenhum estudo foi realizado sobre a freqüência dos genes Dombrock na nossa população, estudamos 450 amostras de DNA, através das técnicas de PCR-RFLP e Microarrays® - HEA Beadchip para determinar a freqüência dos aletos DO {DOA, DOB, HY1, HY2, JO). Dois novos alelos foram identificados baseados em novas combinações de SNPs: alelo DOB- WL (793G, 898G, 323C) e alelo DOA-SH (378C, 624C, 793A). Nossos dados demonstram uma grande complexidade e heterogeneidade dos alelos Dombrock na população brasileira e confirmam a necessidade do estudo molecular em diferentes populações / Abstract: Background: The molecular basis of the Doa and Dob polymorphism, are associated with three single-nucleotide polymorphisms (SNPs) on exon 2 of DO gene: 378C>T, 624T>C and 793A>G, DOA and DOB alleles, respectively. The SNPs 350OT (JO allele) and 323G>T (HY allele) are associated with: Jo(a-) and Hy-negative phenotype. Recently, two new DO alleles were identified using the microarray technology, DOB-SH (378C, 624C, 793G) and DOA-HA (378T, 624T, 793A). Although the molecular background of Dombrock system is well defined, no studies were carried out in the Brazilian population. Methods: We employed PCR-RFLP based assays and a microarray assay to determine the frequency of the DO alleles {DOA, DOB, HY1, HY2 and JO) in Brazilians. We tested DNA of 288 Brazilians people by PCR-RFLP to determine the 793A>G (DOA/DOB), 323G>T {HY), 350OT (JO) and 8980G {HY1IHY2) SNPs. We also tested DNA from 162 blood donors by the HEA Beadchip¿ (BioArray Solutions, USA) to determine the 3780T, 624T>C, 793A>G (DOAIDOB), 350OT (JO allele) and 323G>T (HY) SNPs. Results: Two novel alleles combinations were found in our samples: the 793G SNP (DOB allele) associated with 898G and 323G (DOB-WL) and the SNPs 378C, 624C, 793A and 323G (DOA-SH). We also found the DOB-SH and DOA-HA alleles recently reported. Conclusion: Our data demonstrate high heterogeneity of DO alleles in the Brazilian population and highlight the importance of testing a cohort of different populations to determine the DO allele combinations and establish reliable genotyping to predict the Doa/Dob antigen status / Doutorado / Ciencias Basicas / Doutor em Clínica Médica
26

Estudo de alterações estruturais nos genes CRYAA, CRYGC e CRYGD em pacientes com catarata congênita de uma população brasileira / Study of structural alterations in genes CRYAA, CRYGC and CRYGD in patients with congenital cataract from a braziliam population

Figueirêdo, Eugênio Santana de, 1981- 23 August 2018 (has links)
Orientadores: Carlos Eduardo Leite Arieta, Mônica Barbosa de Melo / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Ciências Médicas / Made available in DSpace on 2018-08-23T06:48:19Z (GMT). No. of bitstreams: 1 Figueiredo_EugenioSantanade_D.pdf: 3323342 bytes, checksum: 042b6873e6f41d4d3c640662d8944a96 (MD5) Previous issue date: 2013 / Resumo: A catarata congênita é a principal causa de cegueira reversível na infância, com prevalência de um a cinco casos por 10.000 nascidos vivos. A forma hereditária corresponde a 50% desses casos, sendo a forma de transmissão autossômica dominante a mais comum. As alterações genéticas podem determinar mudanças no funcionamento das proteínas do cristalino, tais como cristalinas, conexinas, proteínas de transporte de membrana e proteínas de citoesqueleto. As cataratas nucleares e lamelares são as formas mais comuns entre as opacidades congênitas, e as alterações nos genes que codificam as proteínas ?A-cristalina (CRYAA), ?C-cristalina (CRYGC) e ?D-cristalina (CRYGD) têm sido relacionados com esses tipos de catarata. O presente estudo teve como objetivo determinar as alterações estruturais nos genes CRYAA, CRYGC e CRYGD em pacientes com catarata congênita bilateral, formas nuclear e lamelar, do ambulatório de catarata congênita do Hospital das Clínicas da Faculdade de Ciências Médicas da Universidade Estadual de Campinas (UNICAMP). Foram investigadas dez famílias (69 indivíduos), incluindo os casos-índice e seus parentes em primeiro grau. As regiões de codificação e as junções intron/exon foram amplificadas a partir de ácido desoxirribonucleico (DNA) genômico e submetidas à sequenciamento automático. Este estudo identificou seis polimorfismos (SNP) e uma mutação nos três genes investigados (gene CRYAA - SNP D2D, Y18Y e G137G; gene CRYGC - SNP G41G e S119S; gene CRYGD - SNP R95R e mutação Y134C), sendo três deles inéditos na literatura (G137G, G41G e Y134C). No gene CRYGD, a inédita mutação Y134C mostrou-se potencialmente deletéria para o funcionamento da proteína ?D-cristalina / Abstract: Congenital cataract is the leading cause of reversible blindness in childhood, with a prevalence of one to five cases per 10,000 live births. The hereditary form corresponds to 50% of these cases. The most common mode of inheritance is autosomal dominant with high penetrance. Genetic abnormalities determine changes in lens proteins, such as crystallins, connexins, membrane transport proteins and cytoskeletal proteins. The nuclear and lamellar cataracts are the most common among congenital opacities. Abnormalities in ?A-crystallin (CRYAA), ?C-crystallin (CRYGC) and ?D-crystallin (CRYGD) genes have been associated with these phenotypes. The present study aimed to determine the structural alterations in CRYAA, CRYGC and CRYGD genes in patients with bilateral congenital cataract, nuclear and lamellar forms, evaluated at Hospital das Clínicas, Faculdade de Ciências Médicas, Universidade Estadual de Campinas (UNICAMP), Ambulatório de Catarata Congênita. We investigated ten families (69 individuals), including the probands and their first-degree relatives. Coding regions and intron/exon boundaries were amplified from genomic deoxyribonucleic acid (DNA) and directly sequenced. Six single-nucleotide polymorphisms (SNP) and one missense mutation were identified (CRYAA gene - SNP D2D, Y18Y and G137G; CRYGC gene - SNP G41G and S119S; CRYGD gene - SNP R95R and mutation Y134C), three of them unpublished (G137G, G41G and Y134C). In the CRYGD gene, the novel mutation Y134C proved to be potentially damaging for functioning of the ?D-crystallin protein / Doutorado / Oftalmologia / Doutor em Ciências Médicas
27

Proteus mirabilis and cat

Charles, Ian George January 1986 (has links)
Proteus mirabilis PM13 is a well characterized chloramphenicol-sensitive isolate which spontaneously gives rise to resistant colonies on solid media containing chloramphenicol (50ug/ml) at a plating efficiency of between 10-4 and 10-5 per cell per generation. When a chloramphenicol resistant colony is grown in liquid medium in the absence of the antibiotic for I50 generations a population of predominantly sensitive cells arises. The cat gene responsible for the phenomenon is chromosomal, and has been cloned from P.mirabilis PMI3 with DNA prepared from cells grown in the absence or the presence of chloramphenicol. Recombinant plasmids which confer resistance to chloramphenicol carry an 8.5-kb PstI fragment irrespective of the source of host DNA. The location of The cat gene within the PstI fragment was determined by Southern blotting with a cat consensus 'active - site' oligonucleotide (5'-CCATCACAGACGGCATGATG-3') corresponding to the expected amino acid sequence of the active site region of chloramphenicol acetyltransferase. DNA sequence analysis has revealed a high degree of homology between the P. mirabllls cat -gene and the type I ca-t variant (Tn9), 76% at the amino acid level and 73% when nucleotides in the coding sequence are compared. The mechanism for the appearance and disappearance of chloramphenicol resistance in P. mirabilis appears to be associated with a host-specific trans-acting element which controls cat gene expression. A precedent for such a control network is given by phase variation in Salmonella typhimurium, where an invertible DNA segment controls the transcription of a trans-acting regulatory element. A comparison of the 5' regions of the S.typhimurium flagellin genes in and H2, which are alternately expressed by a flip-flop control mechanism with the 5' region of P.mirabilis cat show blocks of homology. Whether or not this homology is significant in the regulation of cat gene expression has not been determined.
28

Towards the synthesis of ubiquitin

Green, Jeremy January 1987 (has links)
No description available.
29

Factors involved in DNA replication in Escherichia coli : the dnaA, groE and pcn gene products

March, John B. January 1988 (has links)
No description available.
30

Study of transgenic mice ectopically expressing the mouse Hoxb-3 gene

凌錦榮, Ling, Kam-wing. January 1998 (has links)
published_or_final_version / Biochemistry / Doctoral / Doctor of Philosophy

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