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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.
1

Synthesis of pyridothiadiazine dioxides as potential potassium ion channel openers

Neill, Colin Gardner January 1995 (has links)
No description available.
2

Onset and recovery with the newer nondepolarising neuromuscular blocking agents

Maddineni, Venkata Rao January 1994 (has links)
No description available.
3

Synthesis of Antispasmodics

Jeanes, Jack K. 08 1900 (has links)
This thesis is a study of the synthesis of antispasmodics.
4

Studies on the mechanism of action of the bioflavonoid Hesperidin methyl chalcone in causing vascular and intestinal smooth muscle to relax

Combs, Alan Brooks 01 January 1964 (has links)
This thesis constitutes a report on a series of studies undertaken on possible mechanisms of action of the bioflavonoid, hesperidin methyl chalcone (HMC), in causing smooth muscle to relax. The term bioflavonoid refers to several compounds that can be extracted from the mesocarp of citrus fruits. They have been the subject of investigation and controversy since 1936. Much of this is covered in a eview by Vogin (1). As mentioned in the review, Szenti-Gyorgyi observed first that crude citrus extracts were more efficient in relieving experimental scurvy than pure extract containing only Vitamin C. The subject of scurvy has been covered in many reviews, and no purpose would be served in describing all these factors at this time. However, since Szent-Gyorgi’s observation, there has been considerable study of the possibility that bioflavonoids are a factor in capillary integrity. Despite all the activity, the necessity of bioflavonoids as a dietary adjuvant has not been established. At this date, almost thirty years after the initial studies, the literature is replete with contradictory statements on almost every phase of bioflavonoid activity. The possibility that HMC might have a direct action on smooth muscle indicated that both in vivo and in vitro studies should be utilized. The in vivo studies consisted of observations on blood pressure and nictitating membranes of cats. The in vitro studies were performed on sections of rabbit ileum.
5

Design, microfabrication and characterization of alkali vapor cells for miniature atomic frequency references / Etude, optimisation fonctionnelle et réalisation de cellules à vapeur alcaline originales pour les références de fréquence atomique miniatures de nouvelle génération

Maurice, Vincent 07 July 2016 (has links)
Les horloges atomiques miniatures présentent des stabilités de fréquence inégalées avec des volumes de quelquescentimètres cubes et des consommations inférieures à 100mW.Dans cette thèse, les paramètres optimaux concernant la conception et la fabrication des cellules à vapeur decésium, un des composant clés de ce type d’horloges, sont définis. Ainsi, les performances de plusieurs cellulesont été caractérisées en condition d’horloge à court et long terme. En parallèle, des solutions sont proposéespour pallier à certaines limitations telles que la plage de température opérationnelle, le coût de fabrication dudispositif et la facilité d’assemblage du module physique.Un nouveau mélange de gaz tampon composé de néon et d’hélium peut étendre la plage de fonctionnementau-dessus de 80 C, en adéquation avec les besoins industriels. A l’inverse des gaz tampon usuels, ce mélangeest compatible avec les dispensers de césium solides, dont la fiabilité est établie.Outre les gaz tampon, les revêtements permettent également de limiter la relaxation induite par les parois dela cellule. Ici, des revêtements d’octadécyltrichlorosilane sont étudiés. Un effet anti-relaxant a été observé dansdes cellules centimétriques et un procédé a été développé pour revêtir des cellules micro-fabriquées.D’autres sources de césium sont présentées pour s’affranchir des inconvénients propres aux dispensers solides.Un dispenser sous forme de pâte, qui peut être déposée collectivement, a été étudié et montre des densitésatomiques stables jusqu’à présent. Un concept de vannes hermétiques micro-fabriquées a été proposé poursceller hermétiquement et séparer des cellules d’un réservoir de césium commun.Les premières étapes vers un module physique micro-fabriqué sont ensuite présentées. En particulier, un designoriginal de cellule combinant des réseaux de diffraction à une cavité en silicium formée par gravure anisotropea été caractérisé et a montré des contrastes CPT remarquables malgré un volume de cavité réduit, ce qui permettraitde réaliser un module physique particulièrement compact. Enfin, des cellules intégrant des résistanceschauffantes et thermométriques ont été fabriquées et leur compatibilité vis-à-vis du champ magnétique généréa été caractérisée dans un prototype de module physique compact. / Chip-scale atomic clocks (CSACs) provide unprecedented frequency stability within volumes down to a fewcubic centimeters and power consumptions as low as 100mW.In this work, we determine the optimal parameters regarding the design and the fabrication of cesium vaporcells, one of the key components of a CSAC. For this purpose, cells were characterized on both short and longtermperformances in clock setups. In addition, we propose solutions to overcome present limitations includingthe operating temperature range, the device microfabrication cost and the ease of integration of the physicspackage.A novel mixture of buffer-gas composed of neon and helium was found to potentially extend the operating rangeof the device above 80 C, meeting the industrial requirements. Unlike the well-known buffer gas compositions,this mixture is compatible with solid cesium dispensers whose reliability is established. As an alternativeto buffer gases, wall coatings are known to limit the relaxation induced by sidewalls. Here, we investigatedoctadecyltrichlorosilane (OTS) coatings. An anti-relaxation effect has been observed in centimeter-scale cellsand a process was developed to coat microfabricated cells.Other cesium sources have been investigated to overcome the drawbacks imposed by solid cesium dispensers. Apaste-like dispenser, which can be deposited collectively, was explored and has shown stable atomic densities sofar. Single-use zero-leak micro valves were also proposed to hermetically seal and detach cells from a commoncesium reservoir.Eventually, the first steps toward a microfabricated physics package were made. In particular, an originalcell design combining diffraction gratings with an anisotropically etched single-crystalline silicon sidewalls wascharacterized and exhibited remarkable CPT contrasts despite a reduced cavity volume, which could lead to amore compact physics package. Finally, cells with integrated heating and temperature sensing resistors werefabricated and their magnetic field compliance was characterized in a compact physics package prototype.
6

Uptake, disposition and acute effects of inhaled organic solvents : sex differences and influence of cytochrome P450 2E1 in human volunteers /

Ernstgård, Lena, January 2003 (has links)
Diss. (sammanfattning) Stockholm : Karol. inst., 2003. / Härtill 5 uppsatser.
7

Intra-nucleus accumbens shell injections of R(+)- and S(-)- baclofen bidirectionally alter binge-like ethanol, but not saccharin, intake in C57Bl/6J mice

Kasten, Chelsea Rae January 2014 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / It has been proposed that the GABAB receptor subtype plays a role in alcoholism and alcohol use disorders (AUDs) (Cousins et al., 2002; Agabio et al., 2012). Specifically, the GABAB agonist baclofen has been looked at extensively in clinical and pre-clinical studies. In various animal models of chronic and intermittent consumption, baclofen has been shown to both increase (Petry, 1997; Smith et al., 1999; Czachowski et al., 2006; Moore et al., 2007) and decrease (Colombo et al., 2000; 2002; 2005; Stromberg, 2004; Moore et al., 2009) drinking. A critical issue in determining pharmacological effects of a drug is using the appropriate animal model. The drinking-in-the-dark (DID) model, developed by Rhodes et al. (2005, 2007), produces high levels of drinking in a binge-like paradigm and has been used to assess many pharmacological targets (e.g. Kamdar et al., 2007; Gupta et al., 2008; Moore et al., 2007; 2009). While DID produces high-levels of binge drinking, it is unclear what areas of the brain are involved in this behavior. A direct way to target areas that are believed to be involved in the circuitry of particular behaviors is through microinjection of drugs (Kiianmaa et al., 2003). Of particular recent interest involving motivated behaviors and addiction is the nucleus accumbens (Acb) (Everitt & Robbins, 2005); specifically the accumbens shell (AcbSh) (e.g. Rewal et al., 2009, 2012; Nie et al., 2011; Leriche et al., 2008). The current study aimed to investigate the role of GABAB receptors in the AcbSh by examining the ability of two different enantiomers of baclofen to alter ethanol and saccharin intake in male C57BL/6J (B6) mice. B6 mice underwent bilateral cannulation surgery targeting the AcbSh. After 48 hours of recovery time, animals began a five day Drinking-in-the-Dark (DID) procedure where they received 20% ethanol or 0.2% saccharin for two hours, three hours into the dark cycle, each day. Throughout the five drinking sessions, animals were kept in home-cage locomotor activity chambers to monitor activity throughout the drinking cycle. Day 4 drinking was immediately preceded by a mock microinjection, whereas Day 5 drinking was immediately preceded by a drug microinjection. Microinjection of one of five doses of baclofen was given in ng/side dissolved in 200 µl of aCSF (aCSF alone, 0.02 R(+)-, 0.04 R(+)-, 0.08 S(-)-, or 0,16 S(-)-). Intake was recorded every twenty minutes on Days 4 and 5. Retro-orbital sinus blood samples were taken from ethanol animals immediately following the Day 5 drinking period to determine blood ethanol concentrations (BECs). A one-way ANOVA on total Day 4 ethanol consumption revealed no baseline differences between dose groups. A one-way ANOVA on total Day 5 ethanol consumption revealed that the 0.04 R(+)- baclofen dose reduced total drinking, but the 0.16 S(-)- baclofen dose increased total drinking (p’s<0.05). This pattern was reflected in the BECs; 0.04 R(+)- baclofen reduced BECs, whereas 0.16 S(-)- baclofen increased BECs (p’s<0.05). These results were also time-dependent, with R(+)-baclofen reducing drinking in the first 20 minutes of the session and S(-)- increasing drinking in the last 40 minutes of the session. There were no effects on saccharin intake. An issue with the locomotor activity boxes led to unreliable locomotor activity counts. However, because there were no drug effects on saccharin consumption, it was concluded that locomotor effects did not contribute to the decreases or increases in ethanol consumption. These results further implicate the role of GABAB receptors in modulating ethanol intake. The bidirectional effects shown highlight the importance of considering enantioselective drug effects when interpreting data. Finally, these results also support previous conclusions that the AcbSh plays an important role in modulating use of drugs of abuse, but not other reinforcers.

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