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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.
131

The Blood-brain barrier in normal and pathological conditions

Zhu, Chunni. January 2001 (has links) (PDF)
Bibliography: leaves 318-367. Examines the blood-brain barrier in normal and pathological conditions induced by intravascular and extravascular insults. Intravascular insults were induced by administration of Clostridium perfringens prototoxin; extravascular insults were induced by an impact acceleration model for closed head injury to induce traumatic brain injury. Also examines the integrity of the blood-brain barrier ultrastructurally and by its ability to exclude endogenous and exogenous tracers. Also studies the expression of 2 blood-brain barrier specific proteins, endothelial barrier antigen (EBA) and glucose transporter 1 (GLUT1)
132

On the cross-sectional form of the patella in several primates

Jones, Christopher David Stanford. January 2003 (has links) (PDF)
"June 2003" Includes bibliographical references (leaves 408-457)
133

The Blood-brain barrier in normal and pathological conditions / by Chunni Zhu.

Zhu, Chunni January 2001 (has links)
Bibliography: leaves 318-367. / x, 367 leaves : ill. ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Examines the blood-brain barrier in normal and pathological conditions induced by intravascular and extravascular insults. Intravascular insults were induced by administration of Clostridium perfringens prototoxin; extravascular insults were induced by an impact acceleration model for closed head injury to induce traumatic brain injury. Also examines the integrity of the blood-brain barrier ultrastructurally and by its ability to exclude endogenous and exogenous tracers. Also studies the expression of 2 blood-brain barrier specific proteins, endothelial barrier antigen (EBA) and glucose transporter 1 (GLUT1) / Thesis (Ph.D.)--University of Adelaide, Dept. of Anatomical Sciences, 2002?
134

On the cross-sectional form of the patella in several primates / Christopher David Stanford Jones.

Jones, Christopher David Stanford January 2003 (has links)
"June 2003" / Includes bibliographical references (leaves 408-457) / [26], 457 leaves : ill. ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (Ph.D.)--University of Adelaide, Dept. of Anatomical Sciences, 2003
135

Inventaire et hiérarchisation de paramètres structuraux facteurs de variabilité intraspécifique de certaines propriétés mécano physiques des tissus ligneux

Gachet, Christophe 16 December 2003 (has links) (PDF)
Si la majeure partie de la variabilité inter spécifique des caractéristiques élastiques du bois normal peut être expliquée par des indicateurs identifiés (nature de l'essence, masse volumique, taux d'humidité), l'étude menée ici permet d'élucider les causes de la variabilité de ces mêmes propriétés au niveau intra spécifique. La simulation de l'anisotropie élastique d'un bois résineux sans défaut est réalisée par l'empilement de quatre échelles de descriptions, faisant passer successivement du niveau des bio polymères essentiels à celui de chaque sous couche élémentaire (Passage 1), de celui de la sous couche à celui de la double paroi cellulaire (Passage 2), de la double paroi au tissu ligneux (Passage 3) et enfin de chacun des tissus ligneux à l'échelle du cerne (Passage 4). Les modèles micromécaniques utilisés à chaque étape restent basés sur la recherche du solide élastique homogène équivalent, par des lois des mélanges simples appliquées à des assemblages série ou parallèle de sous domaines supposés homogènes. Un jeu utile de 22 paramètres réalistes, en regard de données bibliographiques variées, est optimisé sur la base des données caractéristiques élastiques anisotropes du « résineux standard ». Un Résineux Standard Virtuel (RSV) est alors défini. L'outil de modélisation se révèle particulièrement adapté à l'analyse de la sensibilité des propriétés élastiques à la variabilité des paramètres structuraux et ultrastructuraux retenus. Une hiérarchisation objective est alors menée et permet de confirmer le rôle essentiel que joue l'inclinaison des microfibrilles dans S2 (AMF) sur l'anisotropie élastique globale (macroscopique) du matériau. Une campagne expérimentale partielle, menée sur du bois de réaction de trois essences résineuses permet de comparer les résultats prédits par le modèle RSV à ceux obtenus par diverses techniques.
136

Buellia species with pluriseptate spores and the Physciaceae (Lecanorales, Ascomycotina) : Taxonomic, phylogenetic and ultrastructural studies

Nordin, Anders January 2001 (has links)
<p>This dissertation is primarily focused on the <i>Buellia</i> species with pluriseptate spores, often referred to the section or genus <i>Diplotomma</i>, and secondarily on the Physciaceae. An ultrastructural study at family level gives new information on spore characters. Variations in the composition and structure of the spore wall layers and septa are described.</p><p>A phylogenetic analysis of the Physciaceae, based on morphological and chemical characters, is presented. In the resulting trees the species with pluriseptate spores appear in a poorly resolved clade together with other crustose species with 1-septate spores. A subsequent analysis, excluding foliose and fruticose species, shows that the species with pluriseptate spores do not form a monophyletic group, and that only a few are grouped together with the type species of <i>Diplotomma</i>. Due to low resolution, poor branch support, and uncertainty concerning the typification of <i>Buellia</i> all species treated are retained in <i>Buellia</i>.</p><p>Altogether 35 species with pluriseptate spores are treated, including ten new to science, viz. <i>B. aeruginosa</i>, <i>B. morsina</i>, <i>B. muriformis</i>, <i>B. oidaliella</i>, <i>B. pallido-marginata</i>, <i>B. romoletia</i>, <i>B. rubroreagens</i>, <i>B. terricola</i>, <i>B. tombadorensis</i>, and <i>B. tri-septata</i>. Historical outlines are presented, and information on life strategy, morphology, chemistry, ecology, and distribution is given. All species are similar and macroscopically not easily distinguished, having crustose thalli and blackish apothecia, but there is a great variation in microscopic characters, secondary chemistry, substrate preferences, habitat ecology, and distribution range. Several names are typified and many synonyms are listed. References are given to all species referred to <i>Diplotomma</i> in literature.</p>
137

Buellia species with pluriseptate spores and the Physciaceae (Lecanorales, Ascomycotina) : Taxonomic, phylogenetic and ultrastructural studies

Nordin, Anders January 2001 (has links)
This dissertation is primarily focused on the Buellia species with pluriseptate spores, often referred to the section or genus Diplotomma, and secondarily on the Physciaceae. An ultrastructural study at family level gives new information on spore characters. Variations in the composition and structure of the spore wall layers and septa are described. A phylogenetic analysis of the Physciaceae, based on morphological and chemical characters, is presented. In the resulting trees the species with pluriseptate spores appear in a poorly resolved clade together with other crustose species with 1-septate spores. A subsequent analysis, excluding foliose and fruticose species, shows that the species with pluriseptate spores do not form a monophyletic group, and that only a few are grouped together with the type species of Diplotomma. Due to low resolution, poor branch support, and uncertainty concerning the typification of Buellia all species treated are retained in Buellia. Altogether 35 species with pluriseptate spores are treated, including ten new to science, viz. B. aeruginosa, B. morsina, B. muriformis, B. oidaliella, B. pallido-marginata, B. romoletia, B. rubroreagens, B. terricola, B. tombadorensis, and B. tri-septata. Historical outlines are presented, and information on life strategy, morphology, chemistry, ecology, and distribution is given. All species are similar and macroscopically not easily distinguished, having crustose thalli and blackish apothecia, but there is a great variation in microscopic characters, secondary chemistry, substrate preferences, habitat ecology, and distribution range. Several names are typified and many synonyms are listed. References are given to all species referred to Diplotomma in literature.
138

Development and characterization of mechanically actuated microtweezers for use in a single-cell neural injury model

Wester, Brock Andrew 18 January 2011 (has links)
Traumatic brain injury (TBI) affects 1.4 million people a year in the United States alone and despite the fact that 96% of people survive a TBI, the health and socioeconomic consequences can be grave, partially due to the fact that very few clinical treatments are available to reduce the damage and subsequent dysfunction following TBI. To better understand the various mechanical, electrical, and chemical events during neural injury, and to elucidate specific cellular events and mechanisms that result in cell dysfunction and death, new high-throughput models are needed to recreate the environmental conditions during injury. This thesis project focuses on the creation of a novel and clinically relevant single-cell injury model of traumatic brain injury (TBI). The implementation of the model requires the development of a novel injury device that allows specialized micro-interfacing functionality with neural micro environments, which includes the induction of prescribed strains and strain rates onto neural tissue, such as groups of cells, individual cells, and cell processes. The device consists of a high-resolution micro-electro-mechanical-system (MEMS) microtweezer microactuator tool that is introducible into both biological and aqueous environments and can be proximally positioned to specific targets in neural tissue and neural culture systems. This microtweezer, which is constructed using traditional photolithography and micromachining processes, is controllable by a custom developed software-automated controller that incorporates a high precision linear actuator and utilizes a luer-based microtool docking interface. The injury studies will include examination of intracellular calcium concentration over the injury time course to evaluate neuronal plasma membrane permeability, which is a significant contributor to secondary injury cascades following initial mechanical insult. Mechanical strain and strain rate input tolerance criteria will also be used to determined thresholds for cellular dysfunction and death.
139

The ultrastructural characteristics of the reinnervating neuromuscular junction

Lakia, Brent M. January 2006 (has links)
Since the discovery of peripheral nerve regeneration nearly a century ago, the mechanisms that guide this regeneration have been elusive. This project aimed to describe how an axon is able to traverse the environment of the body and precisely reinnervate its target cell. Using a novel technique of combining light and electron microscopy, I observed reinnervating axons in transgenic mice to answer the questions of whether Schwann cells are an important guidance cue for the motor neuron and whether the outgrowing axon is fully developed or the process is a step-wise process of activation. The data suggests that Schwann cell contact is important for the tip of the regenerating axon to guide the axon back to its synapse on the muscle fiber. Further, it seems that the tip of the axon is not capable of synaptic transmission as it lacks active zones, suggesting that reinnervation is a step-wise process. / Department of Physiology and Health Science
140

The role of Rac1 in mouse podocyte cellular process formation and differentiation /

Attias, Ortal. January 2008 (has links)
The role of podocytes in glomerular permselectivity is tightly associated with their intricate morphology, featuring interdigitating foot processes from adjacent cells. The actin cytoskeleton is an integral component of podocyte foot processes and is regulated by a number of proteins expressed in podocytes. Rho-family of small GTPases are known key regulators of the actin cytoskeleton. This study, investigated the role of Rac1 in podocytes, using conditionally immortalized mouse podocytes (MPs). We studied Rho-GTPase activities and morphology/cytoskeleton of differentiating mouse podocytes stably expressing nephrin. We also studied the impact of transfection of various Rho-GTPase mutants and IQGAP1 mutants. We demonstrated that nephrin expression potentiates and sustains Rac1 activity during the differentiation process. We showed that Rac1 contributes to process formation in differentiating MPs and may have a similar role in vivo when podocytes are recovering from injuries.

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