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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.
61

Caracterização de linhagens de cártamo (Carthamus tinctorius L.) em condições de deficiência hídrica e reidratação /

Bortolheiro, Fernanda Pacheco de Almeida Prado, 1990. January 2015 (has links)
Orientador: Marcelo de Almeida Silva / Banca: Dirceu Maximino Fernandes / Banca: Claudiana Moura dos Santos / Resumo: Pouco conhecido e explorado no Brasil, o cártamo (Carthamus tinctorius L.) é uma alternativa interessante para ser incluída em sistemas de rotação de cultura na região do cerrado. A cultura é rústica, tolerante à deficiência hídrica e ao frio, tornando-se uma opção para cultivo de safrinha, porém pouco ainda se conhece sobre a variabilidade genética das linhagens introduzidas no país. O objetivo do trabalho foi avaliar a morfologia e a fisiologia de seis linhagens de cártamo em condições de deficiência hídrica seguida de reidratação. O experimento foi realizado sob cultivo protegido em caixas contendo aproximadamente 300 L de solo. Os tratamentos foram arranjados em um delineamento de blocos ao acaso em esquema fatorial 6 x 2. O primeiro fator foi composto por seis linhagens de cártamo (IMA 02, IMA 04, IMA 10, IMA 14, IMA 16 e IMA 21), e o segundo por dois regimes hídricos (sem e com deficiência hídrica). Todas as caixas foram mantidas em capacidade de campo (CC) até os 55 dias após a semeadura (DAS), depois as plantas foram expostas ao estresse por deficiência hídrica por um período de 30 dias. No tratamento sem deficiência (-D) as plantas foram hidratadas em 100% da capacidade de campo (CC), enquanto que no tratamento com deficiência moderada (+D) as plantas foram mantidas com 50% CC. Após o período de 30 dias de deficiência hídrica, as plantas foram reidratadas por 18 dias, neste período foram realizadas avaliações de potencial hídrico foliar, teor de clorofila, conteúdo relativo de água, tolerância protoplasmática, massa seca de raízes, parte aérea e capítulos, razão raiz/parte aérea, altura de planta, número de capítulos por planta, índice de colheita, peso de mil grãos e produtividade de grãos. Há variabilidade genética entre as seis linhagens de cártamo para todas as características avaliadas. As linhagens IMA 21, IMA 10 e IMA 04 ... / Abstract: Safflower is barely known and explored in Brazil, but has been shown as an interesting alternative for inclusion in crop rotation systems in the Cerrado region. The culture is rustic, tolerant to cold and water deficiency, what make it an option for cultivation in the off-season. The objective of this work was to evaluate the morphology and physiology of six safflower lines under water deficit. The experiment was carried out in a greenhouse in pots contend approximately 300 L of soil. The treatments were arranged in a randomized block design in factorial scheme 6 x 2. The first factor was composed of six lines of safflower (IMA 02, IMA 04, IMA 10, IMA 14, IMA 16 e IMA 21), and the second was the two water regimes (without and with water deficiency). All the boxes were kept at field capacity (FC) to 55 days after seeding (DAS), after the plants were exposed to water deficiency stress for a period of 30 days. The treatment without deficiency (-D) plants were hydrated in 100 field capacity (FC), while in the treatment with deficiency (+D) plants were maintained with 50% FC. After the period of 30 days, the plants were rehydrated for 18 days, in this period were carried out evaluations of leaf water potential, chlorophyll content, relative water content, protoplasmic tolerance, dry mass of root, shoot and flowers, root/shoot ratio, plant height, number of flowers per plant, harvest index, weight of thousand grains and grain yield. There is genetic variability among the six safflower lines for all traits evaluated. The lines IMA 04, IMA 10 and IMA 21 had better recovery of morpho-physiological characteristics after the water deficit and rehydration, in that, the line IMA 14 had better values of number of chapters per plant, relative water content in leaf, and dry matter of the shoot and root; and the line IMA 10 stood out in the variables contents of chlorophyll a, b, total, carotenoids and SPAD index ... / Mestre
62

Sistemática molecular de Utricularia L. (Lentibulariaceae) /

Silva, Saura Rodrigues da. January 2014 (has links)
Orientador: Vitor Fernandes Oliveira de Miranda / Coorientador: Eduardo Custódio Gasparino / Banca: Alessandro de Mello Varani / Banca: Maurício Bacci Junior / Resumo: O uso da sistemática molecular, nas mais variadas abordagens existentes atualmente, é de suma importância para produzir e complementar dados relativos à identificação e história evolutiva das mais diversas espécies. O emprego do DNA, aliado às ferramentas atuais baseadas em sistemática filogenética, pode ser de grande valia para a proposição de um sistema classificatório mais próximo do natural. O gênero Utricularia (Lentibulariaceae) compreende cerca de 250 espécies, das quais cerca de 90 ocorrem nos Neotrópicos e 69 no Brasil, sendo que 20 destas são endêmicas. Muitas espécies ocorrem em ampla variedade de habitats e apresentam alto grau de polimorfismo estrutural, sendo comumente identificadas de forma equivocada, mesmo por especialistas. A delimitação infragenérica também apresenta inconsistências quanto às circunscrições e relações filogenéticas dos subgêneros e seções, fato que evidencia a necessidade de estudos filogenéticos, principalmente baseados em dados moleculares. Assim fica clara a necessidade de pesquisas em sistemática para o grupo, o que poderia trazer informações diagnósticas para as delimitações interespecíficas, assim como para as relações dos táxons infragenéricos (subgêneros, seções e espécies). Sendo assim, o presente estudo teve por objetivos principais avaliar (i) a eficácia da aplicação do DNA "Barcoding" e (ii) realizar o maior estudo filogenético já proposto para Utricularia, baseado em sequências de DNA dos genomas nuclear e cloroplastidial / Abstract: The use of molecular systematics in various existing approaches is currently of paramount importance to produce and supplement data concerning the identification and evolutionary history of several species. The use of the DNA molecule, combined with the current tools based on systematics, can be of great value to the proposition of a classificatory system closer to natural. The genus Utricularia L. (Lentibulariaceae) comprises about 250 species, of which about 90 occur in the Neotropics and 69 in Brazil, and 20 of these are endemic. Many species occur in a wide variety of habitats and has a high degree of structural polymorphism, by that they are commonly mistakenly identified, even by experts. Infrageneric delimitation has also inconsistencies regarding boundaries and phylogenetic relationships of the subgenera and sections, a fact that highlights the need for phylogenetic studies based mainly on molecular data. Thus there is a clear need for systematic research for the group, which could provide diagnostic information for interspecific boundaries as well as the relationships of taxa (subgenera, sections and species). Therefore, the present study was to evaluate the main objectives (i) the effectiveness of the application of DNA barcoding and (ii) hold the largest phylogenetic study already proposed for Utricularia, based on DNA sequences of nuclear and chloroplast genomes / Mestre
63

Genetic predisposition to Alzheimer's disease: studies by linkage and hypothesis-driven candidate gene approach. / CUHK electronic theses & dissertations collection

January 2006 (has links)
Alzheimer's disease (AD) is the most common form of dementia, currently affecting around 17--25 million people worldwide. The typical neuropathological hallmarks of AD are amyloid beta (Abeta) deposition, presence of neurofibrillary tangles and neuronal cell death. Evidence from ongoing studies on the pathogenesis of AD, suggests that several different mechanisms are involved in neurons loss and thus decline of cognitive function. These include the metabolism of amyloid peptide, inflammation, cholesterol metabolism, and hormonal factors. / I have focused on the role of inflammation in the progression of AD. The inflammation hypothesis is based on findings of (1) elevated levels of inflammatory cytokines, such as IL-1, IL-6, TNFalpha, (2) the reduced levels of anti-inflammatory cytokines, like IL-10 in CSF and the blood of AD patients, and (3) activated microglia in the histological section of the patient's brain. On the other hand, the effects of the ApoE gene and differential age of onset between the two sexes suggested a modulation role for cholesterol and sex hormone like estrogen, which may influence the inflammatory response in the brain, so as to modulate the risk of AD. / In this project, the genetic risk factors predisposing to AD were investigated by genetic association studies of candidate genes. Candidate genes were shortlisted by two approaches. (I) Linkage-based candidate genes: Candidate genes were identified from reported loci with linkage to AD genome scan studies. Previous linkage studies of AD families revealed linked loci at 1p36, 1q23, 3p14, 4q32, 6p21, 6q27, 9q22, 10q24, 13q32, 15q26, 19q13 and 21q22. Several candidate genes from these loci including TNFalpha-related genes, TLR2, IGF-1, IFNalpha and MTHFR were selected for this project. (II) Hypothesis-based candidate genes: Candidate genes were selected according to their possible involvement in the inflammation hypothesis of AD. Under the hypothesis-based candidate gene approach, genes that might contribute to the inflammatory response of amyloid deposition were identified. These genes were validated by their expression level in the central nervous system. A further priorization step was carried out to select those genes showing a higher degree of inter-individual variation. Therefore, these genes were more likely to have a genetic/inherited variation at the population level. In other words, they are more likely to be the predisposition genes than genes without inter-individual variation (house-keeping genes are examples of genes showing little inter-individual variation). In this project, genes involved in the inflammatory pathway in the brain, such as IL-10 and HLA-A, and also genes that interact with the inflammatory pathway such as cholesterol related enzymes and estrogen receptors were investigated under the hypothesis-based approach. / This project is based on a case-control genetic association study which comprised of NINCDS-ADRDA diagnosed Chinese patients with AD (n=259) and age-matched non-demented subjects (n=248). Three genes PTGS2 (encoding for COX-2), MxA and ESR1 were selected for an intensive study by investigating their linkage disequilibrium pattern and using tagSNP strategy. TagSNPs selected for each gene were genotyped to investigate their association with the risk of AD. / This study showed that MTHFR, IL-10, HLA-A, CYP46A1, PTGS2 (COX-2) and ESR1 were associated with the risk of AD, and MxA, identified for the first time, was associated with the age of onset of AD. In conclusion, the results of my study further suggested the roles of inflammation in the pathogenesis of AD. / Ma Suk Ling. / "June 2006." / Advisers: Linda C. W. Lam; Nelson L. S. Tang. / Source: Dissertation Abstracts International, Volume: 68-03, Section: B, page: 1417. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2006. / Includes bibliographical references (p. 169-204). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstracts in English and Chinese. / School code: 1307.
64

The FRA 16B locus : long range restriction mapping of 16q13 - 16q22.1 / by Naras Mykolas Lapsys

Lapsys, N. M. January 1993 (has links)
Errata slip inserted at back / Bibliography: leaves 159-192 / vi, 142, [75] leaves : ill ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Summary: Primary object ... was to construct a pulsed field gel electrophoresis (PFGE) derived long range restriction map of this region by physically linking adjacent DNA probes to common high molecular weight genomic DNA fragments / Thesis (Ph.D.)--University of Adelaide, Dept. of Paediatrics, 1994
65

Genetic studies of colorectal cancer /

Skoglund, Johanna, January 2007 (has links)
Diss. (sammanfattning) Stockholm : Karolinska institutet, 2007. / Härtill 4 uppsatser.
66

Genetic dissection of multifactorial disease models in the rat /

Jiao, Hong, January 2002 (has links)
Diss. (sammanfattning) Stockholm : Karol. inst., 2002. / Härtill 6 uppsatser.
67

Multiple sclerosis : linkage analysis and DNA variation in a complex trait /

Modin, Helena, January 2004 (has links)
Diss. (sammanfattning) Stockholm : Karol. inst., 2004. / Härtill 4 uppsatser.
68

Studies of genetic and environmental influences on Parkinson's disease /

Wirdefeldt, Karin, January 2004 (has links)
Diss. (sammanfattning) Stockholm : Karol. inst., 2004. / Härtill 5 uppsatser.
69

Fine mapping of the chromosome 15q13-14 schizophrenia linkage region /

Stephens, Sarah H. January 2008 (has links)
Thesis (Ph.D. in Human Medical Genetics) -- University of Colorado Denver, 2008. / Typescript. Includes bibliographical references (leaves 112-128). Free to UCD Anschutz Medical Campus. Online version available via ProQuest Digital Dissertations;
70

Epidemiology of hereditary prostate cancer : genetic analysis of susceptibility loci incorporating clinical characteristics /

Goode, Ellen Lee. January 2000 (has links)
Thesis (Ph. D.)--University of Washington, 2000. / Vita. Includes bibliographical references (leaves 137-144).

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