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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

An inbred rat model of exercise capacity : the path to identifying alleles regulating variation in treadmill running performance and associated phenotypes

Ways, Justin Andrew. January 2007 (has links)
Dissertation (Ph.D.)--University of Toledo, 2007. / "In partial fulfillment of the requirements for the degree of Doctor of Philosophy in Biomedical Sciences." Title from title page of PDF document. Bibliography: p. 142-183.
12

Pathogenesis of myelin oligodendrocyte glycoprotein induced experimental autoimmune encephalomyelitis in DBA/1 mice /

Abdul-Majid, Khairul-Bariah, January 1900 (has links)
Diss. (sammanfattning) Stockholm : Karol. inst., 2002. / Härtill 4 uppsatser.
13

Effect of exercise training on metabolic intermediate phenotypes in inbred rat strains

Ghosh, Sumona. January 2007 (has links)
Thesis (M.S.)--University of Toledo, 2007. / "In partial fulfillment of the requirements for the degree of Master of Science in Biomedical Sciences." Title from title page of PDF document. Bibliography: p. 59-68.
14

Estabilidade e adaptabilidade para caracteres de produção em linhagens de milho

Koshima, Fernando Akira Takada [UNESP] 16 November 2009 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:26:09Z (GMT). No. of bitstreams: 0 Previous issue date: 2009-11-16Bitstream added on 2014-06-13T19:13:02Z : No. of bitstreams: 1 koshima_fat_me_jabo.pdf: 437027 bytes, checksum: d563e6f656f0c1544f2d9bf446eac284 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Universidade Estadual Paulista (UNESP) / O presente trabalho foi realizado em duas Fazendas Experimentais da Monsanto do Brasil Ltda, localizadas nos municípios de Barretos – SP e Rolândia – PR, na safra verão 2007/08. O objetivo deste trabalho foi avaliar os parâmetros de estabilidade e adaptabilidade de oito linhagens elites de milho (seis utilizadas como fêmea e duas como macho em cruzamentos de híbridos simples comerciais e experimentais) em oito ambientes pelo modelo de EBERHART & RUSSELL. Os ambientes foram caracterizados por duas localidades, duas épocas de semeadura (setembro e outubro) e dois sistemas de manejo de solo (convencional e plantio direto). Utilizou-se o delineamento em blocos casualizados com quatro repetições. Avaliaramse os caracteres de produção de grãos (kg ha-1), rendimento de sacos de sessenta mil sementes por hectare, altura de plantas, altura de espiga e comprimento de espiga. Constataram-se efeitos significativos para as linhagens, ambientes e interação linhagens x ambiente para todas as características avaliadas. Observou-se que todas as linhagens tiveram comportamento imprevisível para produção de grãos. De uma forma geral, observou-se uma maior produção de grãos no ambiente de Rolândia, semeado em setembro no sistema de plantio direto. O ambiente que propiciou a maior produção de grãos, necessariamente não é o ambiente com maior rendimento de sacos de 60 mil sementes por hectare. Os ambientes de Barretos se mostraram propícios para aumentar os parâmetros de altura de planta e altura de espiga. Três das oito linhagens mostraram uma adaptabilidade a ambientes desfavoráveis, enquanto que as demais linhagens... / This work was conducted in two Monsanto’s farms, located in the cities of Barretos – SP and Rolândia – PR during the 2007/08 summer season. The objective of this work was to evaluate the parameters of stability and adaptability of eight Elite inbred lines of maize (six used as female and two used as male in single crosses of commercial and experimental hybrids) in eight environments by EBERHART & RUSSELL’s method. The environments were characterized by two locations, two planting dates (September and October) and two systems of soil tillage (no till and tillage). The experimental design used was a complete randomized block with four replications. It was observed the characters of grain yield (kg ha-1), weight of thousands kernels, yield of sixty thousand kernels bag ha-1, plant height, ear height and ear length. It was evidenced significant effects for inbred lines, environments and inbred lines x environment interaction for all traits evaluated. It was observed that all inbred lines showed unstable behaviour. In general, there was a higher grain yield in environment of Rolândia, planted in September in no till system. The environment with the highest grain yield, not necessarily is the environment with highest yield of 60 thousand kernels bags ha-1. Environments of Barretos showed conditions to increasing the parameters of plant height and ear height. Three of eight inbred lines showed an adaptability to unfavorable environments, while other inbred lines showed an adaptability to favorable environments. Only two inbred lines showed the coefficient of determination above 80%. In general, the inbred line 8-F had the fourth highest grain yield (2675.3 kg ha-1) and ... (Complete abstract click electronic access below)
15

Ação local do alendronato sódico no processo de reparação óssea de fêmures de ratos espontâneamente hipertensos (SHR)

Nobre, Mônica Dal Pian [UNESP] 25 July 2006 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:23:04Z (GMT). No. of bitstreams: 0 Previous issue date: 2006-07-25Bitstream added on 2014-06-13T18:09:13Z : No. of bitstreams: 1 nobre_mdp_me_sjc.pdf: 1018659 bytes, checksum: dbe488e3a217fc107f7384423ac8711f (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Este trabalho analisou a ação local do alendronato sódico no processo de reparação óssea em fêmures de ratos espontaneamente hipertensos (SHR). Foram utilizados quarenta ratos machos e quarenta fêmeas, para a confecção de um defeito ósseo de 2,5mm de diâmetro. De acordo com o material utilizado, criaram-se quatro grupos: controle (C), amido (Am), alendronato 1mol (A1) e alendronato 2mol (A2). Os animais do grupo C não tiveram seus defeitos ósseos preenchidos. Após o período de sete e 21 dias, os animais foram sacrificados. Foi realizada a análise histológica e histomorfométrica e os dados submetidos à análise estatística ANOVA. Aos sete dias, encontrava-se tecido conjuntivo com hemorragia e infiltrado inflamatório ocupando a área do defeito em todos os grupos experimentais e, em alguns grupos, focos de matriz osteóide. Os animais dos grupos A1 e A2 apresentavam uma rede de fibrina no tecido conjuntivo. Aos 21 dias, as trabéculas ósseas fechavam praticamente toda a extensão do defeito nos grupos C e Am. No grupo A1 de animais machos, observavam-se trabéculas que se irradiavam do interior da medula óssea até a área do defeito. Nos demais grupos A1 e A2 constatava-se apenas a presença de tecido conjuntivo, com deposição de fibras colágenas e mínima deposição de matriz osteóide. Um achado histológico marcante foi a formação de tecido ósseo extra-cortical subperiosteal nos animais dos grupos A1 e A2. O estudo concluiu que, neste modelo experimental, a administração local do alendronato sódico não contribuiu para o processo de reparação óssea nas concentrações molares utilizadas. / This study evaluated the local action of alendronate sodium on bone repair in spontaneously hypertensive rats (SHR). A bone defect of diameter 2,5mm was created in forty males and forty females. Four groups were created according to the treatment received: control (C), amido (Am), alendronate 1mol (A1) and alendronate 2mol (A2). The C group did not have their defect filled in with any material. The animals were sacrificed seven and 21 days after the surgical procedure. Histological and histomorfometric analyses were performed and the results submitted to ANOVA statistical analysis. On the seventh day, all groups presented a connective tissue with hemorrhage and inflammatory cells in the bone defect. In some groups osteoid matrix was observed. In A1 and A2 groups, the animals also presented a fibrin deposition. After 21 days, a formation of bone trabeculae was observed closing the superficial extension of the bone defect in C and Am groups. On male rats of group A1, the trabeculae formation projected from inside the bone medulla to the defect site, without completely closing it. In the others animals of groups A1 and A2, bone trabeculae were not observed in the defect site. It was only observed a deposition of dense collagen fibers and minimal osteoid matrix. An important histological feature found in this study was the formation of extra-cortical subperiosteal bone in the animals of A1 and A2 groups. The study concluded that the local administration of alendronate sodium did not contribute for the bone repair, in this experimental model.
16

Análise comparativa da produtividade de híbridos de mamoneira (Ricinus communis L.) obtidos por meio da hibridação convencional e do método de híbridos crípticos /

Toppa, Eder Victor Braganti, 1987. January 2011 (has links)
Orientador: Maurício Dutra Zanotto / Banca: Tammy Aparecida Manabe Kiihl / Banca: Rogério Oliveira de Sá / Resumo: Como conseqüência do melhoramento de populações, novas idéias e métodos surgiram, procurando melhorar a eficiência na obtenção de linhagens e híbridos, bem como diminuir o tempo requerido na sua obtenção. Este é o caso do método dos Híbridos Crípticos, que corresponde essencialmente a um teste precoce de combinação através de cruzamentos entre plantas individuais. Apesar da possibilidade do método dos Híbridos Crípticos representar um ganho de tempo na produção de híbridos, pode ser considerado de uso restrito em programas de melhoramento de espécies alógamas, principalmente em decorrência da excessiva perda de vigor das linhagens femininas com a condução de sucessivas autofecundações. No tocante, supõe-se que em programas de melhoramento de espécies que possuem o sistema reprodutivo do tipo misto, o método possa se configurar como uma ferramenta efetiva em razão de que nestas espécies a depressão endogâmica é desprezível. Ao encontro da necessidade de informações que permitam avaliar o real potencial do método dos Híbridos Crípticos em espécies com sistema reprodutivo do tipo misto, objetivou-se neste trabalho analisar comparativamente o comportamento dos híbridos de mamoneira (Ricinus communis L.) produzidos pelo processo convencional, em que as linhagens são extraídas pelo método "Standard", com os obtidos pelo método dos Híbridos Crípticos. O estudo relata resultados de produtividade de grãos de 24 híbridos interpopulacionais... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: As a consequence of population breeding, new ideas and methods have arisen in order to improve the efficiency in obtaining lines and hybrids, as well as to decrease the time required for their production. This is the case of the Cryptic Hybrids method, which corresponds essentially to an early combination test through breeding between individual plants. Although the Cryptic Hybrids method may represent time gain in hybrid production, it can be considered of restrict use in breeding programs of allogamous species, mainly due to excessive vigor loss in female lines with the conduction of successive self-pollinations. In breeding programs of species with mixed reproductive system, the method is supposed to be an effective tool since endogamic depression is negligible in these species. Based on the need of information that allow assessing the real potential of the Cryptic Hybrids method in mixed reproductive system, this study aimed to comparatively analyze the behavior of castor bean (Ricinus communis L.) hybrids produced through the conventional process, in which the lines are extracted by the Standard method, relative to those obtained by the Cryptic Hybrids method. The study reports grain productivity results for 24 interpopulational hybrids, of which 12 were conventionally produced and the other 12 were produced by the Cryptic Hybrids method; all of them were synthesized at the Department of Plant Production of the School of Agronomical Sciences.Experiments to assess the behavior of hybrids were developed in the crop cycles 2006/2007 and 2007/2008, simultaneously in the municipalities Lins and Penápolis, and were all conducted under randomized block design with four replicates. Grain productivity results for castor bean hybrids evidenced that cryptic hybrids are superior to hybrids conventionally... (Complete abstract click electronic access below) / Mestre
17

INVESTIGATING THE NEURAL CIRCUITRY SUPPORTING OBJECT RECOGNITION MEMORY IN C57BL/6J MICE

Unknown Date (has links)
The hippocampus, a brain region that is part of the limbic system in the medial temporal lobe, is critical to episodic memory, or the memory of autobiographical events. The hippocampus plays an important role in the consolidation of information from short-term memory into more permanent long-term memory and spatial memory which enables navigation. Hippocampal damage in humans has been linked to memory loss, such as in Alzheimer’s disease and other dementias, as well as in amnesia such as in the case of patient H.M. The role of the hippocampus has been well characterized in humans but is less understood in rodents due to contradictory findings. While rodents have served well as model organisms in developing our understanding of the cognitive map that is critical for spatial navigation, there has been substantial contention over the degree to which the rodent hippocampus supports non-spatial memory, specifically the memory for items or objects previously encountered. The overall objective of this research is to gain a better understanding of how neuronal circuits involving the hippocampus and perirhinal cortex function to support object memory in the brain. Chemogenetic technologies such as DREADDs (designer receptor exclusively activated by designer drugs) have proven to be effective tools in remote manipulation of neuronal activity. First, a series of behavioral tasks was used to validate the effects of DREADD inactivation in the CA1 region of dorsal hippocampus in C57BL/6J male mice. DREADD inhibition resulted in significant impairment in the spontaneous object recognition (SOR) task and of spatial memory in the Morris water maze. In conjunction, mice were implanted with bilateral perirhinal cortex guide cannulae to allow for temporary muscimol inactivation during distinct time points in the SOR task to further investigate the nature of its relationship with the hippocampus. The results reveal an unexpected role for the perirhinal cortex in the retrieval of strong object memory. Finally, Arc mRNA expression was quantified in CA1 of dorsal hippocampus and perirhinal cortex following both weak and strong object memory formation. The results indicate that the perirhinal cortex and hippocampus have distinct, yet complementary roles in object recognition memory and that distinction is gated by memory strength. Understanding the neural mechanisms supporting the weak-strong object memory distinction in mice is an important step not only in validating mice as a suitable model system to study episodic memory in humans, but also in developing treatments and understanding the underlying causes of diseases affecting long-term memory such as Alzheimer’s disease. / Includes bibliography. / Dissertation (Ph.D.)--Florida Atlantic University, 2020. / FAU Electronic Theses and Dissertations Collection
18

Normal mandibular morphology of inbred mouse strains

Edwards, Michelle Halum January 2004 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / Even though the molecular events and pathways that underlie craniofacial development and morphogenesis are not fully understood, it is accepted that their orchestration is influenced by the interaction of genetic and environmental factors. Inbred mouse strains represent genetically homogenous groups of individuals. It is established that mice in one strain often differ quite remarkably from mice in other inbred strains. Those phenotypic differences make mice exceptional tools for the dissection of genetic factors that influence normal and abnormal craniofacial morphogenesis. While numerous investigations have focused on abnormal morphogenesis, a comprehensive study of normal craniometric morphology across multiple inbred strains of mice has not been previously performed. The Mouse Phenome Project, an international collaboration of investigators, was formed to systematically phenotype a collection of normal inbred mouse strains. The objectives of our studies were to determine and measure differences in quantitative mandibular traits/variables within and between different inbred mouse strains, and to assess sexual di1norphism through bilateral measuren1ents of the hemimandibles. These studies were a component of the Mouse Phenome Project to collect normal craniometric data from 12 genetically heterogeneous inbred strains utilizing digital images from equal numbers of female and male mice at 7 to 8 weeks of age. Our central hypothesis was that morphometric analysis of mandibular structures from genetically disparate inbred mouse strains would reveal quantifiable differences. The null hypothesis of no difference among the strains for 1nandibular measurements was rejected. Overall, CAST/Ei and MOLF/Ei were consistently small in size measured by body weight with small skeletal structures. There was no strong pattern of body weight and site of skeletal size in the mid and heavy weighted strains. Evidence of sexual dimorphism was supported. Overall, it appears males and females that have the least significance between them are in the DBA/2J strain, followed by A/J. The strain with the most significant difference between males and females is in the C3H/HeJ strain.
19

Normal Mandibular Morphology of Inbred Mouse Strains

Edwards, Michelle Halum January 2004 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / Even though the molecular events and pathways that underlie craniofacial development and morphogenesis are not fully understood, it is accepted that their orchestration is influenced by the interaction of genetic and environmental factors. Inbred mouse strains represent genetically homogenous groups of individuals. It is established that mice in one strain often differ quite remarkably from mice in other inbred strains. Those phenotypic differences make mice exceptional tools for the dissection of genetic factors that influence normal and abnormal craniofacial morphogenesis. While numerous investigations have focused on abnormal morphogenesis, a comprehensive study of normal craniometric morphology across multiple inbred strains of mice has not been previously performed. The Mouse Phenome Project, an international collaboration of investigators, was formed to systematically phenotype a collection of normal inbred mouse strains. The objectives of our studies were to determine and measure differences in quantitative mandibular traits/variables within and between different inbred mouse strains, and to assess sexual dimorphism through bilateral measurements of the hemimandibles. These studies were a component of the Mouse Phenome Project to collect normal craniometric data from 12 genetically heterogeneous inbred strains utilizing digital images from equal numbers of female and male mice at 7 to 8 weeks of age. Our central hypothesis was that morphometric analysis of mandibular structures from genetically disparate inbred mouse strains would reveal quantifiable differences. The null hypothesis of no difference among the strains for mandibular measurements was rejected. Overall, CAST/Ei and MOLF/Ei were consistently small in size measured by body weight with small skeletal structures. There was no strong pattern of body weight and site of skeletal size in the mid and heavy weighted strains. Evidence of sexual dimorphism was supported. Overall, it appears males and females that have the least significance between them are in the DBA/2J strain, followed by A/J. The strain with the most significant difference between males and females is in the C3H/HeJ strain.
20

Long-term dietary folate deficiency and intestinal tumor development in mice

Knock, Erin Heather, 1981- January 2008 (has links)
Epidemiological evidence linking dietary folate deficiency and risk for colorectal cancer is conflicting. Studies using animal models indicate that timing, dose and presence of pre-malignant lesions will influence whether folate deficiency prevents or promotes tumor formation. In this thesis a new model of spontaneous tumor formation due to long-term dietary folate deficiency alone, in non-transgenic mice and without carcinogen induction, is developed. The mechanisms by which folate deficiency might influence cancer risk are also examined. / BALB/c mice, with or without a null allele in a key folate-metabolizing enzyme, Methylenetetrahydrofolate reductase (Mthfr ), develop intestinal tumors due to dietary folate deficiency alone. On folate-deficient (FD) diets, 12.5% of Mthfr+/+ mice and 28.1% of Mthfr+/- mice developed tumors; mice on control diet (CD) did not. C57B1/6 mice (a strain resistant to other methods of tumor induction) placed on the same diets for the same amount of time did not develop any tumors. To investigate possible mechanisms the levels of DNA damage (dUTP/dTTP ratio and p-H2AX staining) and DNA methylation (thin layer chromatography) were examined. FD BALB/c, but not C57B1/6 mice, had a trend towards increased dUTP/dTTP and DNA double-strand breaks and decreased global DNA methylation compared to CD mice. To determine why the FD diet affects the BALB/c and not the C57Bl/6 strain, the expression of genes involved in folate metabolism was examined. Several changes in gene expression were observed. In particular, BALB/c mice had increased Mthfr expression and MTHFR activity compared to C57Bl/6 mice. Increased MTHFR activity may deplete 5,10-methylenetetrahydrofolate supplies for the dTMP synthesis, increasing the dUMP levels and, possibly, DNA damage. The levels of several DNA repair genes were also examined. Two genes involved in base excision repair, Thymine DNA glycosylase (Tdg) and Apurinic/apyrimidinic endonuclease 1 (Apex1), were increased in FD C57B1/6 compared to FD BALB/c mice suggesting increased DNA repair capacity. / These results support the evidence that dietary folate deficiency promotes intestinal tumor formation possibly through increased DNA damage, with subsequent defects in DNA repair.

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