• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 143
  • 93
  • 13
  • 9
  • 7
  • 4
  • 4
  • 4
  • 4
  • 4
  • 4
  • 3
  • 2
  • 2
  • 1
  • Tagged with
  • 318
  • 110
  • 66
  • 32
  • 29
  • 29
  • 27
  • 23
  • 22
  • 21
  • 20
  • 19
  • 17
  • 16
  • 16
  • 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.
51

Morfologia das glândulas sexualmente dimórficas em Gonyleptidae (Arachnida: Opiliones: Laniatores) / Morphology of sexually dimorphic glands in Gonyleptidae (Arachnida: Opiliones: Laniatores)

Costa, Thaiany Miranda 12 December 2017 (has links)
Capítulo 1: Dimorfismo sexual em aberturas glandulares das pernas de três subfamílias de Gonyleptidae (Arachnida: Opiliones: Laniatores) Glândulas sexualmente dimórficas podem não apenas ser informativas taxonomicamente como podem ainda trazer informações importantes sobre a comunicação entre os sexos. Nesse trabalho estudamos a evolução de aberturas glandulares sexualmente dimórficas nas pernas I (basitarso) e pernas IV (presença/ausência de intumescimento e quantidade de poros no metatarso) em uma linhagem monofilética pertencente ao clado K92 composta pelas subfamílias Progonyleptoidellinae, Sodreaninae e parte de Gonyleptinae. Utilizamos Microscopia Eletrônica de Varredura para descrever as aberturas glandulares e compará-las entre exemplares das três subfamílias analisadas. Encontramos aberturas glandulares sexualmente dimórficas na perna I de uma espécie em Progonyleptoidellinae (de seis analisadas), de uma espécie de Gonyleptinae (de quatro analisadas) e em três espécies de Sodreaninae (de seis analisadas). Com relação às aberturas da perna IV, todos os machos estudados possuem maiores quantidades de poros na perna IV do que as fêmeas exceto uma espécie de Gonyleptinae e uma de Sodreaninae. Os machos de todas as espécies estudadas possuem o astrágalo das pernas IV intumescidos, exceto uma espécie em Progonyleptoidellinae. Portanto as aberturas glandulares sexualmente dimórficas na perna I nos machos mostram-se variáveis na linhagem interna ao clado K92 estudada nesse trabalho. Por outro lado, o intumescimento e quantidade de poros na perna IV dos machos parecem ser conservados na linhagem estudada. Capítulo 2: Morfologia interna das glândulas sexualmente dimórficas de Progonyleptoidellus striatus Roewer 1913 (Opiliones: Laniatores: Gonyleptidae) Apesar de diversos trabalhos sugerirem a presença de glândulas sexualmente dimórficas nas quatro subordens de Opiliones, há poucos trabalhos que investigam essas glândulas histologicamente. Morfologia interna fornece importantes informações sobre o funcionamento e composição das secreções. Para isso, utilizamos técnicas histológicas e ultraestruturais para estudar a morfologia interna de duas glândulas de Progonyleptoidellus striatus (Progonyleptoidellinae): uma no basitarso das pernas I e a outra no metatarso das pernas IV. Adicionalmente, investigamos a composição histológica e ultraestrutural da área glandular no metatarso IV. Encontramos diferenças entre os sexos, tanto na morfologia interna como externa: machos possuem intumescimentos das áreas glandulares e internamente possuem células glandulares ausentes nas fêmeas. Encontramos abundantes retículos endoplasmáticos rugosos, lisos e mitocôndrias, além de Complexo de Golgi bem desenvolvido na perna I dos machos. Diferentemente da perna I, não encontramos retículos endoplasmáticos lisos na perna IV, o que pode implicar em composições de produtos secretórios diferentes para as pernas. Nas duas pernas encontramos abundância de vesículas secretoras / Sexually dimorphic glands may not only be taxonomically informative but can also bring important information about communication between the sexes. In this work we studied the evolution of sexually dimorphic glandular openings on legs I (basitarsus) and legs IV (presence/absence of swollen area and quantity of pores on metatarsus) in a monophyletic lineage belonging to clade K92 that include the subfamilies Progonyleptoidellinae, Sodreaninae and part of Gonyleptinae. We used Scanning Electron Microscopy to describe the glandular openings and compare them among specimens of the three subfamilies analyzed. We found sexually dimorphic glandular openings on legs I of one species in Progonyleptoidellinae (out of six analyzed), one specie of Gonyleptinae (out of four analyzed) and three species of Sodreaninae (out of six analyzed). Concerning glandular openings on legs IV, all males studied have more pores than females except for one species in Gonyleptinae and another in Sodreaninae. Males of all species studied have a swollen astragalus IV, except for one species in Progonyleptoidellinae. Therefore, the glandular openings in leg I in males are shown to be variable for the internal lineage to the Clade K92 studied in this work. On the other hand, the swollen area and the greater quantity of pores on legs IV of males seem to be conserved in the lineage studied. Although several studies suggest the presence of sexually dimorphic glands in the four suborders of Opiliones, there are few studies that investigate these glands histologically. Internal morphology provides important information about the functioning of the glands and the composition of secretions. Here we used histological and ultrastructural techniques to study the internal morphology of two glands of Progonyleptoidellus striatus (Progonyleptoidellinae): one in the basitarsus of legs I and another in the metatarsus of legs IV. We found differences between the sexes, both in internal and external morphology, in which males have swollen of the glandular areas and internally the males have glandular cells, absent in females. We found abundant rough, smooth endoplasmic reticulum and mitochondria, as well as Golgi Complex well developed in legs I of males. In contrast, we did not find smooth endoplasmic reticulum in legs IV, which may result in different compositions of glandular products in each leg. In both legs we found abundance great number of secretory vesicles
52

O desenvolvimento embrionário da Piapara - Leporinus elongatus (Pisces, Anostomidae) utilizando marcadores ósseos / Embryonic development of piapara - Leporinus elongatus (Pisces, Anostomidae) using bone markers

Sousa, Erika Zolcsak de 21 May 2014 (has links)
O conhecimento dos estágios iniciais do desenvolvimento embrionário de peixes é de extrema importância para o estudo de espécies nativas com potencial para a piscicultura, uma vez que permite o estabelecimento de diretrizes para a criação destes animais. Este projeto estudou o desenvolvimento embrionário da piapara (Leporinus elongatus), um peixe de grande importância na pesca esportiva e profissional na bacia dos rios Pardo e Jequitinhonha, visando compreender as fases desse animal em diversos estágios de desenvolvimento, utilizando marcadores ósseos que possibilitaram visualizar o desenvolvimento ósseo da espécie. As Proteínas Ósseas Morfogenéticas (BMP-2 e BMP-4) são consideradas moléculas essenciais reguladoras no desenvolvimento embrionário e na formação óssea, sendo ainda pouco estudadas em peixes; tais proteínas puderam ser observadas apenas no estádio larval até o período juvenil, não sendo evidenciadas nos estágios anteriores. Foram utilizadas também técnicas de Microscopia Eletrônica de Varredura e histológicas, onde foi possível visualizar as fases principais do desenvolvimento embrionário, entre elas, clivagens, diferenciação do embrião, formação dos órgãos principais, abertura de boca, pigmentação dos olhos, surgimento das nadadeiras e sistema branquial, dados estes que facilitam a compreensão sobre a ontogenia; além de criar dados embriológicos e anatômicos dessa espécie ainda pouco explorada, conhecimentos estes, imprescindíveis à biologia pesqueira e cultivo das mesmas, sendo também um auxiliar a novas pesquisas. / The knowledge of the early stages of embryonic development in fish is of great importance for the study of native species with potential for aquaculture, since it allows the establishment of guidelines for the breeding of these animals. This project studied the embryonic development of piapara (Leporinus elongatus), a fish of great importance in professional and amateur fishing from the basin of the Pardo and Jequitinhonha rivers, aiming to understand the various stages of development, using bone markers that allowed observation of the bone development in this species. The Bone Morphogenetic Proteins (BMP-2 and BMP-4) are known as key regulatory molecules in embryonic development and bone formation, and information on this subject is scarce in fish. Results shown these proteins could be observed only between the larval to the juvenile stage, not being seen at earlier stages. Scanning electron microscopy and histological techniques, where it was possible to observe the main stages of embryonic development , including , cleavage , embryo differentiation , development of major organs , mouth opening , eye pigmentation , appearance of fins and gills system. This data contributed for the understanding of ontogeny, and provided embryological and anatomical data that may help other studies like reproductive biology of this species that surely will improve reproductive techniques, important goal for raising the piapara.
53

Assembly in Dynamic Nanoscale Systems

Lam, Amy Tsui-Chi January 2015 (has links)
Biological systems are intricate self-assembled systems built from dynamic nanoscale components. These nanoscale components are responsible for many tasks, from subcellular (e.g. DNA replication, cytoplasmic streaming, intracellular transport) to organismal (e.g. intercellular signalling, blood circulation). At each level, biological materials demonstrate complex and dynamic behaviors which are still robust to many perturbations, requiring a balance of dynamism and stability. Being able to emulate biology by dynamically assembling complex systems and structures from nanoscale building blocks would greatly expand the types of materials and structures available, possibly leading to better smart, adaptive, self-healing materials in engineering. The overarching goal of this dissertation is to further the understanding of assembly in dynamic nanoscale systems. To this end, in vitro assays of kinesin motor proteins and microtubule cytoskeletal filaments are employed, providing a well-tested, minimalist, and convenient model system. In these assays, the kinesin motors are attached to the surface of the flow cell and the microtubule filaments are propelled over them. As the majority of past studies in active self-assembly of microtubules have been performed with biotin-labeled microtubules with streptavidin as a cross-linker (a "sticky" gliding assay), the first three parts of this dissertation focus on that system. In the first part, the adsorption kinetics of the streptavidin cross-linker onto the microtubule, which determines the interaction strength between microubule building blocks, is studied. The adsorption curve suggests that this is a negatively cooperative process, and here, the cause of the apparent negative cooperativity in the adsorption process is elucidated as a combination of steric and electrostatic interactions. In the second part, the difference between kinesin-propelled assembly and diffusion-driven assembly is investigated. While the kinesin-propelled microtubule assay has been used for over a decade, a control experiment comparing the active motor-driven system to a passive diffusion-driven system had never been performed. The control experiments showed conclusively that the passive system resulted in smaller and more disordered structures. Furthermore, these results fit well with existing models. The third part investigates the origins of microtubule spools observed in kinesin-propelled microtubule gliding assays, where the microtubules are allowed to cross-link via streptavidin and biotin. These microtubule spools have long been considered an example of a non-equilibrium structure which arises in motor-driven assembly. These spools exist in a dynamic state, having been observed to unwind in previous studies, and store large amounts of bending energy. Determining the origins of these spools is a first step towards understanding how to induce dynamically stable states. Finally, in the last part, a new dynamic system is engineered in which the microtubule assembles its own kinesin track as it moves along the surface while kinesin tracks which are not being used spontaneously disassemble. Thus, this system is stable enough to promote the motion of microtubules over the surface, but dynamic enough to allow for components to be recycled and assembled as needed. While such systems have been realized with mesoscopic to macroscopic components, such a system had not been realized in the nanoscale. As such, the realization of this system is the first step towards designing biomimetic active materials. Throughout this dissertation, the importance of short-range interactions on assembly kinetics is highlighted. The findings presented not only further the understanding and theory behind self-assembly in active nanoscale systems, but also further push the boundaries of experimentally realized systems.
54

Ultraestrutura e expressão das enzimas: citocromo P450 aromatase e citocromo P450c17 (17-α-hidroxilase/17,20-liase) nas diferentes fases do desenvolvimento da via espermática e espermatogênese em cutia (Dasyprocta sp.) criada em cativeiro / Ultrastructure and expression of enzymes: cytochrome P450 aromatase and cytochrome P450c17 (17-α-hydroxylase/17,20-lyase) in different developmental stages of spermatogenesis and excurrent canals in agouti (Dasyprocta sp.) kept in captivity

Arroyo, Maria Angélica Machado 05 July 2013 (has links)
Espécies silvestres com grande potencial zootécnico devem ser exploradas de forma racional a fim de se evitar a extinção das mesmas. Assim se dá a importância de pesquisas voltadas à reprodução daquelas criadas em cativeiro, como a cutia (Dasyprocta sp.). Este animal é um mamífero e roedor vivente, em sua maioria, na Caatinga brasileira. A ultraestrutura é a base para determinar os estágios celulares e, assim, facilitar as comparações dos processos entre cutias e roedores silvestres ou outros mamíferos. As enzimas P450 aromatase e P450c17 são responsáveis pela regulagem da produção de estrógenos e andrógenos, respectivamente. Considerando a hipótese de que o comportamento de expressão das enzimas do complexo citocromo P540 permanece o mesmo no testículo e na via espermática de cutias durante as fases de desenvolvimento sexual, objetivou-se observar a atuação das enzimas P450 aromatase e P450c17 (17-α-hidroxilase/17,20-liase) nas diferentes fases do desenvolvimento sexual, detalhar a ultraestrutura dos componentes desta via e constatar o desenvolvimento do processo espermatogênico. Segmentos do ducto deferente, epidídimo e testículo de 28 cutias machos em diferentes idades (um dia, 2-14 meses) foram fixados em paraformoldeído e glutaraldeído. O material foi coletado no Centro de Multiplicação da Universidade Federal Rural do Semiárido, Mossoró, RN (Autorização IBAMA nº 2028236/2008). Foram feitos: histologia, seguindo o protocolo padrão para hematoxilina e eosina; processamento para corte semifino (azul de toluidina); microscopia eletrônica de transmissão e varredura; e imunohistoquímica. Este trabalho foi pioneiro ao observar que o epidídimo de cutias é composto por células basais, células principais, células haloides e, quando impúbere, por células \"limpas\", e por células apicais, quando a partir da puberdade. O ducto deferente de cutias antes da puberdade era caracterizado por duas camadas musculares, possivelmente devido à falta de trânsito espermático. No epitélio germinativo foram encontradas, em sua maioria, células em prófase I, principalmente em paquíteno. A espermiogênese é completa quando na pré-puberdade, entretanto, a espermiação ocorre a partir dos 9 meses de idade. A expressão da enzima P450 aromatase variou ao longo do desenvolvimento sexual, sendo na puberdade seu pico de atividade. A P450c17 não mostrou nenhuma ação em qualquer fase sexual. Pode-se concluir que o epitélio germinativo testicular e intersticial, bem como o epitélio pseudoestratificado estereociliado do epidídimo e do ducto deferente de cutias criadas em cativeiro sofrem mudanças morfológicas e funcionais ao longo do desenvolvimento sexual. As atividades androgênicas preponderantes em cutias criadas em cativeiro ocorrem no período da puberdade. / Wild species with great potential livestock should be explored rationally in order to prevent the extinction of the same. Thus is the importance of research aimed at reproducing those bred in captivity, such as agouti (Dasyprocta sp.). This animal is a mammal and rodent living mostly in the Brazilian Caatinga. The ultrastructure is the basis for determining the stages and thus facilitates comparisons of cases between agouti and wild rodents or other mammals. The enzymes P450 aromatase and P450c17 are responsible for regulating the production of estrogens and androgens, respectively. On the assumption that the behavior of expression of the enzymes of complex cytochrome P540 remains the same in the testis and excurrent canals of the agouti during the stages of sexual development, aimed to observe the activity of the enzymes P450 aromatase and P450c17 (17-α- hidroxilase/17,20-lyase) in different stages of sexual development, detail the ultrastructure of the components of this pathway and observe the development of spermatogenesis. Segments of the vas deferens, epididymis and testis of 28 agouti males at different ages (1 day, 2-14 months) were fixed in glutaraldehyde and paraformoldehyde. The material was collected on Center of Multiplication of Federal Rural University of the Semi-arid, Natal, RN (IBAMA Authorization No. 2028236/2008). Were made: histology following the standard protocol for hematoxylin and eosin; processing to semithin (blue toluidine), electron microscopy of transmission and scanning; and immunohistochemistry. This work was pioneered by observing that the epididymis is composed by basal cells, principal cells, haloids cells; and for clean cells when impubertal and apical cells after puberty in agoutis. The vas deferens before puberty was characterized by two muscle layers, possibly due to the lack of sperm transit. In the germinal epithelium were found mostly cells in prophase I, mainly in pachytene. Spermiogenesis is complete when prepubertal phase; however, spermiation takes place from 9 months of age. The expression of enzymes of the cytochrome complex varied over sexual development and peak activity of P450 aromatase was at puberty. The P450c17 showed no action at any stage of sexual development. It can be concluded that the testicular germinal epithelium and interstitial epithelium as well as the pseudostratified estereociliated epithelium of the epididymis and vas deferens undergo morphological and functional changes during the sexual development. Androgenic activities prevalent in agoutis kept in captivity occur during puberty.
55

Farfantepenaeus brasiliensis (Crustacea : Penaeoidea): morfologia do hepatopâncreas e sua relação com os metais pesados encontrados no litoral sul do Espírito Santo

Nunes, Erika Takagi [UNESP] 12 December 2011 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:30:56Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-12-12Bitstream added on 2014-06-13T19:19:45Z : No. of bitstreams: 1 nunes_et_dr_rcla.pdf: 1685568 bytes, checksum: fc39ac0ad20fd32933d7b0fda0680782 (MD5) / O hepatopâncreas dos crustáceos, também conhecido como glândula digestiva, passa por modificações morfo-funcionais em resposta a fatores como dieta, variações de temperatura, ciclo de muda, estágio reprodutivo e contaminação. Este trabalho objetivou analisar, morfologicamente, através de técnicas de microscopia eletrônica e de luz, o hepatopâncreas de fêmeas adultas do camarão-rosa Farfantepenaeus brasiliensis, em dois diferentes estágios de desenvolvimento gonadal, coletadas em Guarapari, Espírito Santo, Brasil, bem como relacionar esta espécie às condições ambientais, comparativamente ao camarão Xiphopenaeus kroyeri. A microscopia eletrônica de varredura evidenciou hepatopâncreas de tamanhos semelhantes nas fêmeas com gônadas desenvolvidas (DE) e naquelas esgotadas (ES), apresentando-se como um órgão não-lobado e recoberto por tecido conjuntivo com poros. Histologicamente, foram identificados cinco tipos celulares nos túbulos: células E (embrionárias), R (reabsortivas), F (fibrilares), B (vesiculares) e M (basais). Comparado às DE, o epitélio hepatopancreático das fêmeas ES mostrou-se mais escamoso, acidófilo, delimitando um amplo lúmen que contem partes das células B e R; nestas, ainda, as células M estiveram mais evidentes. As células R mostraram escassez em organelas, mitocôndrias apicais, vacúolos marcados para polissacarídeos ácidos, além de gotas lipídicas vistas principalmente nas fêmeas ES. As células F, fortemente marcadas pelo azul de bromofenol, apresentaram vesículas de secreção próximas às microvilosidades, retículo endoplasmático rugoso bem desenvolvido, em arranjo circular ou com cisternas dilatadas. As células B foram marcadas pela presença de grandes corpos digestivos com conteúdo polissacarídico neutro, sendo eliminado, posteriormente... / The hepatopancreas of crustaceans, also known as the digestive gland, undergoes morphological and functional changes in response to factors such as diet, temperature variations, moult cycle, reproductive stage and contamination. This study aimed to analyze, morphologically, by means of electron and light microscopies, the hepatopancreas of adult females of the pink shrimp Farfantepenaeus brasiliensis at two different stages of gonadal development, collected in the southern coast of Espirito Santo, Brazil, as well as to relate this species to the environmental conditions, compared to Xiphopenaeus kroyeri shrimp. The scanning electron microscopy revealed similar size in the hepatopancreas of females with developed gonads (DE) and those with exhausted gonads (ES). It presents as a non-lobed organ covered by connective tissue with pores. Histologically, five cell types were identified in tubules: E (embryonic), R (reabsorptive), F (fibrillar), B (vesicular) and M (basal). Compared to those DE females, the hepatopancreas from ES females showed a more flattened epithelium, acidophilus and delimiting a large lumen which contains parts of R and B cells; in these, also, the M cells were more evident. R cells showed shortage in organelles, apical mitochondria, vacuoles marked for acid polysaccharides, and lipid droplets seen mainly in female ES. F cells were strongly marked by bromophenol blue and presented secretory vesicles near the microvilli, well-developed rough endoplasmic reticulum in circular arrangement, or even with dilated cistern. B cells were marked by the presence of large digestive bodies with neutral polysaccharide content, being later eliminated inside the tubular lumen. The observed features also allowed us to infer the possible stages of moult in which the shrimps were. Although some... (Complete abstract click electronic access below)
56

Localização da proteína fosfolipase C zeta em extratos esppermáticos de gatos domésticos normospérmicos /

Villaverde, Ana Izabel Silva Balbin. January 2010 (has links)
Orientador: Maria Denise Lopes / Banca: Fernanda da Cruz Landim e Alvarenga / Banca: Nereu Carlos Prestes / Banca: Claudia Barbosa Fernandes / Banca: Nei Moreira / Resumo: O estudo da proteína fosfolipase C zeta (PLCζ), considerada o fator espermático ativador do oócito em mamíferos, pode beneficiar algumas técnicas de reprodução assistida, como a injeção espermática intracitoplasmática e transferência nuclear, por propiciar conhecimento a respeito do processo de fertilização e a possibilidade de utilização da PLCζ presente nos extratos espermáticos. Portanto, o objetivo deste estudo foi localizar a PLCζ em extratos provenientes do citosol e matriz perinuclear de espermatozóides de gatos domésticos normospérmicos e teratospérmicos. Amostras de sêmen foram colhidas de seis gatos adultos: normospérmicos (n=3), teratospérmicos (n=2) e de qualidade seminal intermediária (n=1). As proteínas do citosol foram extraídas utilizando os procedimentos de sonicação, ultracentrifugação, ultrafiltração e precipitação em sulfato de amônio. Por sua vez, as proteínas da matriz perinuclear foram extraídas após incubação em Na2CO3, sonicação, ultracentrifugação, ultrafiltração e precipitação em sulfato de amônio. Com base na avaliação ultraestrutural dos espermatozóides e dosagem de proteína total, foi confirmada a eficiência de ambos os protocolos de extração. As amostras da matriz perinuclear apresentaram 3,3 vezes menos proteína total e diferente perfil protéico na eletroforese unidimensional e bidimensional quando comparadas as amostras obtidas do citosol. Após análise das proteínas encontradas, foi concluído que nos extratos espermáticos do citosol e matriz perinuclear de gatos domésticos normospérmicos e teratospérmicos estão presentes proteínas de peso molecular semelhante ao previamente descrito para a proteína PLCζ em outras espécies de mamíferos / Abstract: The study of phospholipase C zeta protein (PLCζ), considered as the oocyte activating sperm factor in mammals, could benefit some assisted reproductive techniques, such as intracytoplasmic sperm injection and nuclear transfer, by providing knowledge about the process of fertilization and the possibility of using the PLCζ contained in the sperm extracts. Thus, the aim of this study was to localize the phospholipase C zeta (PLCζ) protein in extracts from the spermatozoa cytosol and perinuclear matrix of normospermic and teratospermic domestic cat. Sperm samples were collected from six adult male cats: normospermic (n=3), teratospermic (n=2) and with intermediate sperm quality (n=1). Proteins from the cytosol were extracted using the procedures of sonication, ultracentrifugation, ultrafiltration and precipitation in ammonium sulfate. On the other hand, proteins from perinuclear matrix were extracted after incubation in Na2CO3, sonication, ultracentrifugation, ultrafiltration and precipitation in ammonium sulfate. Based on the ultrastructural analysis of the spermatozoa and total protein determination, the efficiency of both extraction protocols was confirmed. Samples from perinuclear matrix showed 3.3 times less total recovered protein and different protein profile in the uni- and bidimensional electrophoresis when compared to the samples obtained from the cytosol. After protein profile analysis, it can be concluded that several proteins showing similar molecular weight to that previously described for PLCζ protein in other mammalian species are presented in both sperm extracts from cytosol and perinuclear matrix of normospermic and teratospermic domestic cats / Doutor
57

Proton chemical shift prediction of A·A mismatches in B-DNA duplexes.

January 2007 (has links)
Lai, Kin Fung. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2007. / Includes bibliographical references (leaves 92-97). / Abstracts in English and Chinese. / Title Page --- p.i / Thesis Committee --- p.ii / Abstract (In English) --- p.iv / Abstract (In Chinese) --- p.v / Acknowledgement --- p.vi / List of Figures --- p.xii / List of Tables --- p.xiv / List of Symbols and Abbreviations --- p.xvi / Chapter 1. --- Introduction --- p.1 / Chapter 1.1 --- Chemical Shift Predictions of Nucleic Acids --- p.1 / Chapter 1.1.1 --- Chemical Shift --- p.1 / Chapter 1.1.2 --- Chemical Shift Prediction of Double Helical DNA and RNA --- p.1 / Chapter 1.1.3 --- Chemical Shift Prediction of Random Coil DNA --- p.2 / Chapter 1.1.4 --- Applications of Nucleic Acid Chemical Shift Prediction --- p.4 / Chapter 1.2 --- General Review of DNA Structure --- p.4 / Chapter 1.2.1 --- Structure and Nomenclature of Nucleotide --- p.4 / Chapter 1.2.2 --- Structure of Polynucleotide --- p.5 / Chapter 1.2.3 --- Sugar Conformation in Nucleotide --- p.5 / Chapter 1.2.4 --- Double Helical DNA Conformation --- p.7 / Chapter 1.3 --- A.A Mismatches in DNA Duplexes --- p.8 / Chapter 1.3.1 --- Mismatches in DNA Duplexes --- p.8 / Chapter 1.3.2 --- Biological Significance of A. A Mismatches --- p.9 / Chapter 1.4 --- Purpose of the Work --- p.9 / Chapter 2 --- Materials and Method --- p.10 / Chapter 2.1 --- Overview of the Proposed Prediction Method --- p.10 / Chapter 2.1.1 --- Nearest Neighbor Model --- p.10 / Chapter 2.1.2 --- Base Pair Replacement Approach --- p.10 / Chapter 2.2 --- Sample Design --- p.11 / Chapter 2.2.1 --- Reference Sequences for Obtaining Triplet Values and Correction Factors --- p.11 / Chapter 2.2.2 --- Sequences for Verifying the Base Pair Replacement Approach --- p.12 / Chapter 2.2.3 --- Sequences for Testing Chemical Shift Prediction Accuracy --- p.12 / Chapter 2.3 --- Sample Preparation --- p.13 / Chapter 2.4 --- NMR Experiments --- p.14 / Chapter 2.4.1 --- Non-labile Proton Resonance Assignment --- p.14 / Chapter 2.4.2 --- Labile Proton Resonance Assignment --- p.16 / Chapter 2.5 --- Validating the Assumption in Reference Hairpin Model Samples --- p.17 / Chapter 3 --- Establishment of Proton Chemical Shift Prediction method of A.A Mismatches in B-DNA Duplexes --- p.18 / Chapter 3.1 --- Resonance Assignment --- p.18 / Chapter 3.1.1 --- Non-labile Protons --- p.18 / Chapter 3.1.2 --- Labile Protons --- p.20 / Chapter 3.2 --- Validating the Assumption in Reference Hairpin Model Samples --- p.21 / Chapter 3.3 --- Extraction of A.A Mismatch Triplet Chemical Shift Values --- p.22 / Chapter 3.4 --- Calculation of the 5´ة- and 3´ة-Correction Factors --- p.24 / Chapter 3.5 --- Chemical Shift Prediction Using Triplet Values and Correction Factors Extracted from Top Strands of refA.A(XAY) and refA.T(XAY) --- p.27 / Chapter 3.6 --- Chemical Shift Prediction Using Triplet Values and Correction Factors Extracted from Bottom Strands of refA.A(XAY) and refA.T(XAY) --- p.28 / Chapter 4 --- Testing of Proton Chemical Shift Prediction of A.A Mismatches in B- DNA --- p.29 / Chapter 4.1 --- Prediction Result Using Triplet Values and Correction Factors Extracted from the Top Strands of refA.A(XAY) and refA.T(XAY) --- p.29 / Chapter 4.2 --- Prediction Result Using Triplet Values and Correction Factors Extracted from Bottom Strands of refA.A(XAY) and refAT(XAY) --- p.30 / Chapter 4.3 --- Applicability of the Base Pair Replacement Approach --- p.31 / Chapter 4.3.1 --- Chemical Shifts and 3JH1´ةH2´ة of refT.A(XTY) Sequences --- p.31 / Chapter 4.3.2 --- Correction factors Extracted from the Top Strands of refA.A(XAY) and refT.A(XTY) --- p.31 / Chapter 4.3.3 --- Prediction Result Using Correction Factors Extracted from the Top Strands of refA.A(XAY) and refT.A(XTY) --- p.33 / Chapter 5 --- Conclusion --- p.35 / Appendix I NOE Sequential Assignment of refA.T(XAY) - (A) Aromatic Protons at 25 °C; (B) Labile Protons at 25 °C --- p.36 / Appendix II NOE Sequential Assignment of refA.A(XAY) - (A) Aromatic Protons at 25 °C; (B) Labile Protons at 5 °C --- p.40 / Appendix III H1'-H2'/H2´ح region of DQF-COSY Spectra of refA.T(XAY) at 25 °C --- p.44 / Appendix IV H1'- H2'/H2´ح region of DQF-COSY Spectra of refA.A(XAY) at 25 °C --- p.46 / Appendix V H3' region of HSQC Spectra of refA T(XAY) at 25 °C --- p.48 / Appendix VI H3' region of 1H-31̐ư HSQC Spectra of refA.A(XAY) at 25 °C --- p.50 / Appendix VII 3JH1'h2'1H and 31P Chemical Shifts of refA T(XAY) --- p.52 / Appendix VIII 3JH1'H2'and 31P Chemical Shifts of refA.A(XTY) --- p.60 / Appendix IX NOE Sequential Assignment of refT .A(XTY) - (A) Aromatic Protons at 25 °C; (B) Labile Protons at 25 °C --- p.68 / Appendix X H1'-H2'/H2''region of DQF-COSY Spectra of refT.A(XTY) --- p.72 / Appendix XI H3'region of H-31P HSQC Spectra of refT.A(XTY) --- p.74 / Appendix XII 3JH1'H2'1H and 31P Chemical Shifts of refT.A(XTY) --- p.76 / Appendix XIII Chemical Shifts of Testing Sequences --- p.84 / Reference --- p.92
58

Morphology and synapse distribution of olfactory interneurons in the procerebrum of the terrestrial snail Helix aspersa

Ratté, Stéphanie. January 1999 (has links)
No description available.
59

Maintenance of ultrastructural integrity during dehydration in a desiccation tolerant angiosperm as revealed by improved preservation techniques

Smith, Michaela Madeleine, 1972- January 2002 (has links)
Abstract not available
60

Delayed Recovery of Mitochondrial Function in Rat Liver after Releasing Biliary Obstruction

MIYATA, KANJI 06 1900 (has links)
No description available.

Page generated in 0.4536 seconds