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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.
251

Chemical cues and the molecular basis of olfactory chemoreception in caudate amphibians /

Kiemnec, Karen M. January 1900 (has links)
Thesis (Ph. D.)--Oregon State University, 2010. / Printout. Includes bibliographical references (leaves 124-140). Also available on the World Wide Web.
252

Role of the calcium-stimulated adenylyl cyclases in neuroplasticity /

Wong, Scott Thaddeus. January 2000 (has links)
Thesis (Ph. D.)--University of Washington, 2000. / Vita. Includes bibliographical references (leaves 128-157).
253

Genetic patterns of demography and diversity in eastern North Pacific rockfishes (genus Sebastes) /

Johansson, Mattias Lars. January 1900 (has links)
Thesis (Ph. D.)--Oregon State University, 2011. / Printout. Includes bibliographical references (leaves 92-102). Also available on the World Wide Web.
254

Neural Diversity in the Drosophila Olfactory Circuitry: A Dissertation

Lai, Sen-Lin 31 July 2007 (has links)
Different neurons and glial cells in the Drosophila olfactory circuitry have distinct functions in olfaction. The mechanisms to generate most of diverse neurons and glial cells in the olfactory circuitry remain unclear due to the incomprehensive study of cell lineages. To facilitate the analyses of cell lineages and neural diversity, two independent binary transcription systems were introduced into Drosophila to drive two different transgenes in different cells. A technique called ‘dual-expression-control MARCM’ (mosaic analysis with a repressible cell marker) was created by incorporating a GAL80-suppresible transcription factor LexA::GAD (GAL4 activation domain) into the MARCM. This technique allows the induction of UAS- and lexAop- transgenes in different patterns among the GAL80-minus cells. Dual-expression-control MARCM with a ubiquitous driver tubP-LexA::GAD and various subtype-specific GAL4s which express in antennal lobe neurons (ALNs) allowed us to characterize diverse ALNs and their lineage relationships. Genetic studies showed that ALN cell fates are determined by spatial identities rooted in their precursor cells and temporal identities based on their birth timings within the lineage, and then finalized through cell-cell interactions mediated by Notch signaling. Glial cell lineage analyses by MARCM and dual-expression-control MARCM show that diverse post-embryonic born glial cells are lineage specified and independent of neuronal lineage. Specified glial lineages expand their glial population by symmetrical division and do not further diversify glial cells. Construction of a GAL4-insensitive transcription factor LexA::VP16 (VP16 acidic activation domain) allows the independent induction of lexAop transgenes in the entire mushroom body (MB) and labeling of individual MB neurons by MARCM in the same organism. A computer algorithm is developed to perform morphometric analysis to assist the study of MB neuron diversity.
255

Génomique intégrée des neuroblastomes olfactifs : implications anatomopathologiques et thérapeutiques / Integrated genomics of olfactory neuroblastoma : pathologic and therapeutic implications

Classe, Marion 14 December 2017 (has links)
Les neuroblastomes olfactifs (NBOs) sont des tumeurs rares de la base du crâne. Les outils de classification de ces tumeurs sont insuffisants, il n’existe notamment aucune classification moléculaire des NBO. La biologie de ses tumeurs est mal connue. Nos travaux se sont appuyés sur l’analyse des exomes, du transcriptome, du méthylome et des caractéristiques histopathologiques et immunitaires d’une série de 59 NBOs bien annotés cliniquement. Nous avons mis en évidence l’existence de 2 sous-types de NBO présentant un profil d’expression et un profil anatomo-clinique différent. Le type neural, correspond à une tumeur bien différenciée, peu agressive, présentant des caractéristiques plutôt neuronales et partageant des caractéristiques phénotypiques avec les progéniteurs directs de neurones olfactifs. Le type basal correspond à une tumeur moins différenciée, plus agressive, ayant des caractéristiques plutôt embryonnaires, partageant des caractéristiques phénotypiques avec les cellules basales de renouvellement de l’épithélium olfactif. Nous avons mis en évidence que la charge mutationnelle était plus élevée dans le type basal, avec notamment des mutations IDH2 R172 récurrentes, associées à un phénotype CpG Island Methylator (CIMP). Nous avons également montré que les NBOs de type basal étaient infiltrés par un nombre plus important de lymphocytes T avec, dans certaines tumeurs, une expression plus marquée de checkpoints immunitaires et de facteurs immunosuppresseurs. Ce travail ouvre la perspective d’une classification moléculaire permettant de mieux stratifier les patients et ouvre également le champ de nouvelles stratégies thérapeutiques dans ces tumeurs rares. / Olfactory neuroblastomas (ONBs) are rare tumors arising in the skull base. Classification tools are poor, notably; no molecular classification of ONB has been reported. Literature data about their cell of origin, the existence of molecular therapeutic targets or their immune environment being scarce, the biology of these tumors is still poorly understood. Our work was based on exome, transcriptome and methylome analysis, but also on histopathological and immune characteristics of a series of 59 clinically well annotated ONBs. We highlighted 2 sub-types of ONB showing different expression and clinicopathologic patterns. The neural type is a well differentiated, poorly aggressive tumor which shows neurons characteristics and shares phenotypic similarities with olfactory neuron progenitors. The basal type is a less differentiated tumor, displaying an aggressive phenotype, with embryonic phenotypical characteristics, which shares similarities with basal renewing cells of the olfactory epithelium. We showed that the mutational load was higher in basal tumors, with notably recurrent IDH2 R172 mutations associated with a CpG Island Methylator Phenotype (CIMP). We also showed that basal type ONBs were infiltrated by a greater number of T cells with, in some cases, a higher expression of immune checkpoints and immunosuppressive factors. This work paves the way towards a new molecular classification which will allow a better stratification of patients and will open the field of new therapeutic strategies for this rare tumor.
256

Simulação computacional do sistema olfativo de vertebrados. / Computational simulation of the vertebrate olfactory system.

Fábio Marques Simões de Souza 30 April 2002 (has links)
Este trabalho descreve uma simulação computacional biologicamente plausível do sistema olfativo de vertebrados. O modelo construído foi capaz de reproduzir satisfatoriamente características importantes observadas no sistema olfativo de vertebrados, incluindo a recepção de diferentes concentrações e tipos de odores no epitélio olfativo e a propagação dessa informação para o bulbo. Ele também tornou possível a observação de diferentes padrões de resposta odorífera, tanto no epitélio como no bulbo, associados a diferentes odores usados nas simulações. / This work describes a biologically plausible simulation of the olfactory system of vertebrates. The constructed model was capable of reproducing satisfactorily important characterisitics observed in the vertebrate olfactory system, including the reception of different concentrations and odor types at the epithelium and the propagation of this information to the olfactory bulb. Also, it made possible the observation of the different response patterns, both in the epithelium as in the olfactory bulb, associated with different odors used in the simulations.
257

Análise dos efeitos de enriquecimento olfativo nos comportamentos reprodutivos de cação-lixa, Ginglymostoma cirratum (Bonnaterre, 1788) (Elasmobranchii: Orectolobiformes) / Analysis of olfactory enrichment effects on reproductive behaviors of nurse shark, Ginglymostoma cirratum (Bonnaterre, 1788) (Elasmobranchii: Orectolobiformes)

Colbachini, Helen [UNESP] 19 February 2018 (has links)
Submitted by HELEN COLBACHINI (hcolbachini@gmail.com) on 2018-04-18T00:26:17Z No. of bitstreams: 1 Helen Colbachini_Dissertação Zoologia.pdf: 2645399 bytes, checksum: 2048a35ec7b7829866e0808d2a32a21a (MD5) / Approved for entry into archive by Adriana Aparecida Puerta null (dripuerta@rc.unesp.br) on 2018-04-18T14:22:04Z (GMT) No. of bitstreams: 1 colbachini_h_me_rcla.pdf: 2470317 bytes, checksum: c173d0ab9c5bac9898e58bb4a42e3e4a (MD5) / Made available in DSpace on 2018-04-18T14:22:04Z (GMT). No. of bitstreams: 1 colbachini_h_me_rcla.pdf: 2470317 bytes, checksum: c173d0ab9c5bac9898e58bb4a42e3e4a (MD5) Previous issue date: 2018-02-19 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / O cação-lixa, Ginglymostoma cirratum, é um dos tubarões mais exibidos em Aquários no mundo, porém a taxa de insucesso reprodutivo desta espécie ainda é alta. Considerando a provável mediação olfativa para a sua reprodução e o potencial de enriquecimentos ambientais afetarem positivamente a reprodução de animais sob cuidados humanos, o presente trabalho objetivou avaliar se a utilização de enriquecimento olfativo geraria efeitos na exibição de comportamentos reprodutivos de cação-lixa, bem como se esse efeito seria diferencial de acordo com o sexo. Este trabalho também propôs avaliar a proximidade física como um indicativo de comportamento proceptivo de fêmeas. O estudo foi dividido em três fases (controle – sem enriquecimento; enriquecimento a curto prazo – recém aplicado; enriquecimento a longo prazo – após incorporado na rotina de manejo) e foi realizado em duas instituições com manejos distintos. O enriquecimento utilizado foi manjericão comercial (Ocimum basilicum), inicialmente apresentado na forma de bloco de gelo e, para o estudo a longo prazo, apresentado na forma de extrato. As observações comportamentais ocorreram através da amostragem focal com registro instantâneo, totalizando 120 horas de observação por animal, divididas em dois momentos (ativo e inativo). Os resultados indicam maior atividade relacionada ao período noturno e às sessões de alimentação; maior frequência de ocorrência de comportamentos reprodutivos no período inativo, no sexo masculino e nas fases com enriquecimento ambiental; maior riqueza comportamental em machos e na fase de enriquecimento a longo prazo. A análise de proximidade mostrou-se eficiente como indicativa de comportamento sócio-sexual, assim como o comportamento “movimento corporal”. É importante atentar que os efeitos são diferenciados para os sexos, sendo essencial o acompanhamento próximo e a criação de cronogramas para evitar uma super-estimulação ou uma habituação ao enriquecimento. Apesar disso, o fato da maior frequência de comportamentos reprodutivos ter ocorrido no período inativo facilita este acompanhamento, visto que se refere ao período de funcionamento de instituições zoológico (dia). Por fim, com a definição dos comportamentos proceptivos faz-se possível determinar quais fêmeas estão receptivas e assim delinear programas reprodutivos mais eficientes. Esses resultados destacam a importância de possuir um manejo que estimule constantemente os sentidos dos elasmobrânquios, especialmente em instituições que desejem realizar programas de reprodução. / Nurse shark, Ginglymostoma cirratum, is one of the most exhibited sharks in Aquariums in the world, however, the reproductive failure rate of this species continues high. Since there probably is an olfactory mediation for its reproduction and environmental enrichments have a potential positive effect on the reproduction of captive animals, the present study aimed to evaluate whether the use of olfactory enrichment would generate effects in the exhibition of reproductive behaviors of nurse sharks, as well as if this effect would be differential according to sex. This study also proposed to evaluate physical proximity as an indicative of proceptive female behavior. The study was divided in three phases (control – without enrichment, shortterm enrichment – recently applied, long-term enrichment – after being incorporated into the management routine) and was performed in two institutions with distinct husbandry. The enrichment used was commercial basil (Ocimum basilicum), which was initially prepared as an ice block and, for the long-term phase, presented as an extract. The behavioral observations were performed through focal sampling with instantaneous recording, totaling 120 hours of observation per animal, divided into two moments (active and inactive). Results show greater activity related to nocturnal period and feeding sessions; greater frequency of occurrence of reproductive behaviors in the inactive period, with males and during the long-term enriched phase. The proximity analysis was efficient as indicative of socio-sexual behavior, as well as the “body movement” behavior. It is important to note that the enrichment effects are differentiated for the sexes and therefore, close monitoring and scheduling are essential to avoid over-stimulation or habituation to the enrichment. Nevertheless, the fact that the greater frequency of reproductive behavior occurred during the inactive period facilitates this monitoring, since it refers to the operating hours of zoological institutions (daytime). Finally, with the definition of proceptive behavior, it is possible to determine which females are receptive and thus, to delineate more efficient breeding programs. These results highlight the importance of having a management that constantly stimulates the senses of elasmobranchs, especially in institutions that aims to carry out breeding programs.
258

Enriquecimento ambiental para gatos domésticos (Felis silvestris catus L.): A importância dos odores / Environmental enrichment for domestic cats (Felis silvestris catus L.): The importance of odors

Gisele Cristina Guandolini 22 May 2009 (has links)
A transferência de odores entre os gatos e o meio ambiente ocorre por meio de contatos corporais, como também pela eliminação de excretas. Pelo enriquecimento ambiental é possível promover a exibição de comportamentos mais próximos dos naturais e extinguir comportamentos não desejáveis, contribuindo, assim, para a saúde física e psicológica dos animais. Este trabalho teve como objetivo promover estímulos no ambiente para que os gatos desempenhassem comportamentos característicos da espécie. Foram utilizados gatos domésticos (Felis silvestris catus L.), castrados (por volta do primeiro ano de vida) ou não, de ambos os sexos. Os animais foram mantidos todos juntos em um abrigo de gatos, cuja população era de aproximadamente 110 indivíduos, sendo 41 machos e 69 fêmeas. Cinco testes foram realizados durante dezesseis meses e foi registrado: quais os comportamentos são manifestados na área dos testes (grooming, urinar, defecar e verificações olfativas), quais indivíduos realizaram mais esses comportamentos (fêmeas, machos e machos castrados) e qual categoria animal apresentou maior número de contato. Foram utilizados o método animal focal e a amostragem do comportamento. Observou-se que existe diferença significativa nos contatos entre machos e fêmeas (Fr= 10, 362, p= 0, 006) e averiguou-se que essa diferença também ocorre quando os grupos são agregados (contatos F_M-M_M e contatos F_F-F_M). Fêmeas e machos castrados, quando comparados pelo teste Wilcoxon, apresentaram diferenças significativas no tempo dedicado ao comportamento de grooming(z= 2,95, p= 0,036). Os gatos são indivíduos bastante curiosos, o que facilita o desenvolvimento de um enriquecimento ambiental mais barato com o alcance de respostas comportamentais adequadas. / The transfer of odors between the cats and the environment occurs through physical contact, but also for disposal of excreta. For environmental enrichment can promote behaviors closer view of the natural and extinguish unwanted behaviors, thus contributing to the physical and psychological health of animals. This work aimed to promote the environment for stimuli that cats play behaviors characteristic of the species. We used domestic cats (Felis silvestris catus L.), castrated (around the first year of life) or not, of both sexes. The animals were kept together in a shelter for cats, whose population was approximately 110 individuals, 41 males and 69 females. Five tests were conducted over sixteen months and was recorded: which behaviors are manifested in the area of testing (grooming, urinate, defecate and verification olfactory), which made most people these behaviors (females, males and castrated males) and which category of animal presented more contact. We used the method of sampling and focal animal behavior. It was observed that there is significant difference in contacts between males and females (F = 10, 362, p = 0, 006) and checked that this difference also occurs when the groups are aggregated (F_M contacts and contacts F_F-M_M-F_M ). Females and castrated males, when compared by Wilcoxon test showed significant differences in time devoted to grooming behavior of (z = 2.95, p = 0.036). Cats are very curious people, which facilitates the development of an environmental enrichment cheaper with the range of appropriate behavioral responses.
259

Avaliação do transplante de células tronco do epitélio olfatório de ratos em coelhos da raça Nova Zelândia submetidos a trauma medular / Evaluation of transplantation of stem cells from rat olfactory epithelium in rabbits subjected to spinal cord injury

Marcio Nogueira Rodrigues 08 July 2011 (has links)
As células-tronco do epitélio olfatório possuem a capacidade de diferenciação, regeneração de neurônios olfatórios e atuam no processo de mielinização das fibras nervosas. O objetivo desse trabalho foi verificar o potencial terapêutico de células-tronco do epitélio olfatório de ratos Wistar em terapia celular em coelhos submetidos à lesão medular. Foram utilizados ratos com idade de 2 meses e coelhos da raça nova Zelândia obtidos no Biotério do Departamento de Patologia da Faculdade de Medicina Veterinária e Zootecnia da Universidade de São Paulo. Os fragmentos do epitélio olfatório dos ratos foram tratados e colocadas em cultivo em DMEM-F12 suplementado. Foram testadas nos coelhos nova Zelândia 4 tipos de lesão medular, hemisecção dorsal e ventral e secção lateral e total. Foi realizado teste de potencial teratogênico em camundongos NUDE e para terapia foram transplantadas 5x105 células em 4 coelhos submetidos a lesão medular ventral. A morfologia predominante das células em cultivo era fibroblastóide. Os ensaios de curva de crescimento e tendência a formação de colônia demonstraram que as condições de cultivo destas células estavam adequadas. Foi encontrada positividade para Vimentina, Oct-4, GFAP, OMP, Nanog, Citoqueratina-18 e Beta tubulina em imunofluorescência. Em citometria de fluxo foi encontrada negatividade para CD 113, CD 117 e Stro-1 e positividade para Vimentina, Nanog e OMP. Em análise por imunohistoquíca verificou-se marcação positiva para Vimentina, OMP, GFAP e Nanog. Verificou-se marcação positiva no material coletado por retrovírus GFP. Houve melhora clínica nos animais avaliados 21 dias após o transplante de células com retorno de alguns reflexos como o de propriocepção consciente e colocação tátil, o mesmo apresentou ainda reflexo de pedalagem. Conclui-se que o melhor modelo para indução da lesão medular em coelhos é a hemisecção ventral da medula e que as células-tronco olfatórias de ratos Wistar possuem grande potencial terapêutico em animais submetidos à lesão medular. / Stem cells from olfactory epithelium are capable of differentiation, regeneration of olfactory neurons and act in the myelination process of nerve fibers. The aim of this study was to verify the therapeutic potential of stem cells from the olfactory epithelium of Wistar rats in cell therapy in rabbits subjected to spinal cord injury. Rats were aged 2 months and New Zealand rabbits obtained in the bioterio of the Animal Pathology Department, Faculty of Veterinary Medicine, at University of Sao Paulo. Samples of the olfactory epithelium of rats were treated and placed in culture in DMEM-F12 supplemented. Four types of spinal cord injury were tested in New Zealand rabbits: hemisecction dorsal and ventral, total and lateral section. The teratogenic potential test was made in NUDE mices. For therapy were transplanted 5x105 cells in 4 rabbits subjected to spinal cord injury in the ventral region. The cells showed predominant fibroblastoid morphology. Tests for growth curve and colony formation demonstrated that culture conditions in these cells were suitable for the development of these cells. In the immunofluorescence analyses the cells showed positive reaction for vimentin, Oct-4, GFAP, OMP, Nanog, cytokeratin-18 and beta tubulin. In flow cytometry analyses was found negative reaction for CD 113, CD 117 and Stro-1 and positive reaction for vimentin, Nanog and OMP. In immunohistochemistry analysis were observed positive reaction for vimentin, OMP, GFAP and Nanog. Positive labeling was showed on the collected material for GFP. Clinical improvement occurred in the animals evaluated 21 days after cell transplantation. With some reflections about how the placement of conscious proprioception and tactile, it also presented a reflection of pedaling. After this, we concluded that the better model for induction of spinal cord injury in rabbits is the hemisecction ventral and the olfactory stem cells of Wistar rats showed a great therapeutic potential in animals subjected to spinal cord injury.
260

Estudo da substantividade de uma composição aromática na pele em função do ciclo menstrual / Substantivity study of the fragrance on the skin in function of menstrual cycle

Claudia Silva Cortez Pereira 29 January 2009 (has links)
O estudo da substantividade de uma composição aromática/fragrância em pele em função do ciclo menstrual é de relevância científica, pois a literatura científica menciona, sem conclusões significativas, que os hormônios sexuais manifestam inúmeros efeitos fisiológicos na pele e de percepção olfativa, principalmente nas fases ovulatória e lútea comparadas às demais fases do ciclo menstrual. O presente trabalho teve como objetivo investigar se os hormônios sexuais influenciam na sensibilidade olfativa e, se as alterações fisiológicas na pele afetam a performance da fragrância durante o ciclo menstrual. Para tanto, foi empregada a avaliação sensorial e determinada a escala de magnitude categórica LMS (escala de magnitude com rótulos) para a quantificação da intensidade de perfume no experimento. O estudo da estabilidade normal da composição aromática definiu a melhor composição para a fase experimental. O estudo clínico foi realizado em quatro fases do ciclo menstrual (menstrual, folicular, ovulatória e lútea) e, cada uma, a intensidade de perfume foi avaliada em 5 tempos experimentais (inicial; 1,5; 3,0; 4,5 e 6h). Em paralelo, foram analisadas as medidas biomecânicas da pele (perda de água transepidérmica, corneometria e sebumetria) e um indivíduo do sexo masculino foi considerado como controle de pele no estudo. As medidas biomecânicas não foram significativas para influenciar na sensiblidade olfativa. A percepção foi maior na fase lútea quando a mulher avaliava sua pele e menor quando avaliava a pele do homem em relação às outras fases. Conclui-se que os hormônios sexuais afetaram a sensibilidade olfativa em diferentes fases do ciclo, porém as alterações fisiológicas provavelmente não interferiram na percepção olfativa e este fato nos orienta para o desenvolvimento de fragrâncias e instiga à pesquisa de matérias-primas aromáticas que influenciam no comportamento da mulher ou até mesmo na atração entre os sexos. / The Substantivity study of the aromatic composition/fragrance on the skin in function of menstrual cycle is the big issue because of the scientific literature says, with no significant conclusions, which the sex hormones demonstrate wide physiologic effects in the skin and in the olfactory perception, particularly, in the ovulatory and luteal phases versus other ones of the menstrual cycle. The aim of this study was to investigate if the sex hormones influence on the olfactory perception and their physiologic effects in the skin might change the fragrance performance during the menstrual cycle. Thus it was employed a sensory evaluation and was defined the LMS scale (labeled magnitude scale) to score the fragrance intensity in the assessment. The stability test defined the best aromatic composition/fragrance to the experiment. The clinical study was conducted in four phases of the menstrual cycle (menstrual, follicular, ovulatory and luteal) and, each one, the perfume intensity was evaluated in 5 experimental times (initial, 1,5h, 3,0h, 4,5h and 6h) in parallel with the bioengineer measurement of the skin (transepidermal water loss, moisturizing and sebum content) and a man was considered a skin control in the experiment. The bioengineer measurement was no significant to influence the olfactory perception; however, the fragrance perception in the luteal phase was higher when the woman evaluated her skin and lower when she evaluated man skin in comparison to the other phases. In summary, the sex hormones influenced the olfactory perception in different phases of the menstrual cycle; however, the skin physiologic effects did not affect the olfactory perception probably and this issue helps to development fragrances and instigates to discover aromatic raw materials that influence woman behavior or even the sex attraction.

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