• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 29
  • 20
  • 6
  • 5
  • 2
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • Tagged with
  • 82
  • 24
  • 19
  • 18
  • 11
  • 10
  • 8
  • 7
  • 6
  • 6
  • 5
  • 5
  • 5
  • 4
  • 4
  • 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.
21

Effect of N2 on the mutagenic and killing activities of ICR-170 in Neurospora crassa

Whong, Wen-Zong. Brockman, Herman E. January 1976 (has links)
Thesis (Ph. D.)--Illinois State University, 1976. / Title from title page screen, viewed Dec. 7, 2004. Dissertation Committee: H.E. Brockman (chair), M. Neville, A. Richardson, F. Schwalm, D. Weber. Includes bibliographical references (leaves 125-138) and abstract. Also available in print.
22

Studies of vibronic exciton interactions between pairs of chromopores / Daniel Fornasiero

Fornasiero, Daniel January 1981 (has links)
Typescript (photocopy) / 164 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 Physical and Inorganic Chemistry, 1982
23

Investigation of the geometry of interaction of planar dyes with DNA by linear dichroic absorption spectroscopy

Kelly, Gregory Raymund January 1974 (has links)
3 articles published by author included in back of book / 115 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 Physical and Inorganic Chemistry, 1976
24

I. The selective catalytic hydrogenation of pyrrole, indole, carbazole, and acridine derivatives II. The Claisen condensation of carbethoxypyrroles /

Coonradt, Harry Lynn, January 1940 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1940. / Typescript. Includes abstract and vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 85-87, 105).
25

Borane-Containing Ligands Based on Thioxanthene, Xanthene and Acridine: Syntheses and Platinum Coordination Chemistry

Blackwell, Natalie 09 1900 (has links)
<p> Ligand backbones based on xanthene, thioxanthene and acridine (XPB, TXPB and APB) have been targeted as scaffolds for the formation of rare compounds containing Lewis basic phosphine and Lewis acidic borane moieties. The resulting complexes with Pt(O) and Pt(II) reagents are expected to possess diverse reactivity compared to traditional platinum phosphine adducts owing to the strategically appended borane Lewis acid. </p> <p> Two ligands, 2,7-di-(tert-butyl)-4-diphenylboryl-5-diphenylphosphino-9,9dimethylthioxanthene (TXPB) and 2,7-di-(tert-butyl)-4-diphenylboryl-5diphenylphosphino-9,9-dimethylxanthene (XPB), have been synthesized and reacted with the platinum reagents [PtCl2(COD)], [PtMe2(COD)] and [Pt(nbe)3]. In the case of TXPB, two new Pt(II) compounds [PtCl(μ-Cl)(TXPB)] and [PtMePh(TXPB^(Ph,Me))] have been formed, isolated and characterized. In both compounds, X-Ray analysis shows that the S and the P atoms bind to the Pt center drawing the metal into the vicinity of the B group. In [PtCl( μ-Cl)(TXPB)], a chloride is seen to bridge between the Pt and B, whereas [PtMePh(TXPB^(Pb,Me))] shows that a methyl groups has been transferred to the boron with concomitant transfer of a phenyl group to Pt. Reaction with the platinum(O) precursor [Pt(nbe)3] led to formation of an unstable complex, tentatively assigned as [Pt(nbe)TXPB]. Analogous studies with the new xanthene-derived ligand, XPB, led to starkly different results. In the reaction with [PtCl2(COD)], an insoluble product, perhaps a dinuclear complex with bridging chlorides, was formed. No reaction occurred with [PtMe2(COD)], presumably because of non-participation of the 0 ligand. However, with [Pt(nbe)3], a stable complex, [Pt(nbe)2XPB], was observed. </p> <p> Synthesis of a third ligand scaffold APB has been initiated where the pyridine moiety is expected to allow strong chelation of Pt as observed with TXPB. An advanced intermediate AFBr has been synthesised where the backbone has been created through a ring closure reaction positioning two different halides as required for sequential addition of the phosphine and borane groups of the target compound. </p> / Thesis / Master of Science (MSc)
26

Synthesis and biological evaluation of polyamine DNA-intercalator conjugates and synthesis of N-hydroxyamide containing peptides

Wang, Lu 01 January 1999 (has links)
No description available.
27

Métabolisme oxydatif de la carbamazépine et effets indésirables de type hypersensibilité : contribution du métabolisme sanguin des dérivés acridiniques, modifications des profils métaboliques au cours du DRESS syndrome et par les comédications antiépileptiques, et aspects oxydatifs environnementaux / Oxidative metabolism of carbamazepine and hypersensitivity adverse reactions : contribution of the blood metabolism of the acridinic derivatives, change in metabolic profile at DRESS state and related to anticonvulsive comedications, and environmental oxidative aspects

Mathieu, Olivier 19 November 2010 (has links)
La carbamazépine est une molécule antiépileptique très largement utilisée au point de devenir un marqueur environnemental de l'activité humaine. Elle donne lieu à des réactions d'hypersensibilité particulières, rares mais potentiellement létales, associant manifestations cutanées, hyperéosinophilie et atteintes multi-organiques (DRESS syndrome). Les hypothèses physiopathologiques font principalement appel aux métabolites de la carbamazépine mais la voie métabolique minoritaire des dérivés acridiniques est peu explorée. Les résultats obtenus à partir de stimulations ex vivo en laboratoire indiquent d'une part que l'acridine stimule la sécrétion d'interleukine-5 (facteur de croissance principal des éosinophiles), et d'autre part que la formation d'acridine et d'acridone est possible dans le sang à partir de métabolites primaires (époxyde et iminostilbène). Les données cliniques montrent une diminution des taux sanguins du 9-hydroxyméthyl-10-carbamoylacridan et du rapport acridine/acridone au cours de l'état de DRESS. Le co-traitement par l'acide valproïque majore le taux basal d'IL-5 et oriente en partie le profil métabolique vers celui du DRESS. L'étude de l'action des procédés oxydatifs environnementaux indique que les lits bactériens et le lagunage augmentent le rejet d'acridine. Nos travaux en pharmacologie humaine positionnent l'acridine et l'acridone comme des métabolites sanguins, a minima marqueurs et a maxima acteurs de la physiopathologie du DRESS. L'établissement d'un profil métabolique apparaît justifié lors d'une co-thérapie avec l'acide valproïque chez des patients à terrain atopique. L'acridine semble également être un marqueur environnemental d'intérêt. / Carbamazepine is a very usefull antiepileptic drug, widely used at the point of becoming an environmental marker of human activity. It is giving rise to rare but potentially lethal hypersensitivity reactions, with specific combination of skin manifestations, eosinophilia and multi-organ damage (DRESS syndrome). The pathophysiological hypotheses rely primarily to metabolites of carbamazepine, but the minor pathway of acridinic derivatives is little explored.The results obtained from ex vivo stimulation in our laboratory suggest both that acridine stimulates the secretion of interleukin-5 (main growth factor of eosinophils), and that the formation of acridine and acridone is possible in blood from primary metabolites (epoxide and iminostilbene). Clinical data show a decrease in blood levels of 9-hydroxymethyl-10-carbamoylacridan and in the ratio (acridine / acridone) during the state of DRESS. Co-treatment with valproic acid increases the basal rate of IL-5 and diverts, at least in part, to the metabolic profile of DRESS. The study of the action of environmental oxidative processes indicates that the purification processes by trickling filters and stabilization ponds increase the release of acridine, while activated sludge systems have little impact.Our work in human pharmacology positions acridine and acridone as regular blood metabolites, involved as markers or actors of the pathophysiology of DRESS. The determination of the metabolic profile appears warranted for atopic patients requiring co-therapy with valproic acid. Acridine also appears to be a marker of environmental interest.
28

Conception et Synthèse d'Hétérocycles Azotés Polyfonctionnalisés Biologiquement Actifs: Des Acridines aux Quinazolines

Zeghida, Walid 30 November 2007 (has links) (PDF)
Ce travail porte sur la conception de dérivés d'aminoacridine et de quinazoline. Dans une première partie, nous avons préparé des dérivés d'aminoacridine ortho-hydroxyméthylée. Pour synthétiser ces dérivés nous avons mis au point une stratégie efficace et générale mettant en jeu la préparation d'un intermédiaire-clé qui peut ensuite être fonctionnalisé. A partir de ce dernier nous avons préparé des dérivés substitués par un motif guanidine. Nous avons également préparé un dérivé iodé afin d'étudier sa distribution cellulaire par microscopie ionique (SIMS). Les propriétés biologiques (IC50 et distribution cellulaire) de ces nouveaux composés ont été évaluées sur des cellules cancéreuses et les résultats obtenus ont confirmé l'intérêt de cette nouvelle famille d'aminoacridine comme anticancéreux.<br />Dans une seconde partie nous avons mis au point une nouvelle méthodologie de synthèse de 2-alkylamino-4(3H)-quinazolinones. Nous avons ainsi préparé différents dérivés comportant un motif quinazolinone à partir d'amines aromatiques et hétérocycliques. Certains de ces dérivés ont fait l'objet d'études biologiques préliminaires (effet cytostatique, ligand ADN-quadruplex) et les résultats obtenus sont très encourageants.
29

CONFOCAL MICROENDOSCOPY: CHARACTERIZATION OF IMAGING BUNDLES, FLUORESCENT CONTRAST AGENTS, AND EARLY CLINICAL RESULTS

Udovich, Joshua Anthony January 2008 (has links)
Ovarian cancer is the fifth leading cause of cancer related deaths among women. Early detection improves the chances of survival following diagnosis, and new imaging modalities have the potential to reduce deaths due to this disease. The confocal microendoscope (CME) is a non-destructive in-vivo imaging device for visualization of the ovaries that operates in real-time. Two components of the CME system are evaluated in this paper, and initial results from an ongoing clinical trial are presented.Fiber-optic imaging bundles are used in the CME imaging catheter to relay images over distances of up to 20 feet. When detecting fluorescent signals from investigated tissue, any fluorescence in the system can potentially reduce contrast in images. The emission and transmission properties of three commercially available fiber optic imaging bundles were evaluated. Emission maps of fluorescence from bundles were generated at multiple excitation wavelengths to determine the profile and amount of fluorescence present in bundles manufactured by Sumitomo, Fujikura, and Schott. Results are also presented that show the variation of transmittance as a function of illumination angle in these bundles. Users of high-resolution fiber-optic imaging bundles should be aware of these properties and take them into account during system design.Contrast is improved in images obtained with the CME through the application of topical dyes. Acridine orange (AO) and SYTO 16 are two fluorescent stains that are used to show the size, shape, and distribution of cell nuclei. Unfortunately, little is known about the effects of these dyes on living tissues. This study was undertaken to evaluate the effects of dye treatment on peritoneal tissues in mice. Seventy-five Balb/c mice were split into five groups of fifteen and given peritoneal injections of dye or saline. The proportions of negative outcomes for the control and test groups were compared using confidence intervals and the Fisher's exact test. No significant difference was determined between the groups. These data provide preliminary results on determining the effect of these dyes on living tissues.Preliminary results of a clinical trial are presented showing in-vivo use of the CME for imaging of the ovaries. This is the first portion of a two part study to demonstrate the clinical diagnosis potential of the CME system. A mobile version of the bench-top CME was modified to be used in the clinic. Fluorescein sodium is used as an initial contrast agent in these studies to demonstrate fluorescence imaging. Twenty patients were successfully imaged, and results of this study have allowed progression to a clinical validation study showing the diagnostic capabilities of the CME.
30

DNA Interactions and Photocleavage by Anthracene, Acridine, and Carbocyanine-Based Chromophores

Mapp, Carla 23 September 2013 (has links)
The interaction of small molecules with DNA has been extensively studied and has produced a large catalogue of molecules that non-covalently bind to DNA though groove binding, intercalation, electrostatics, or a combination of these binding modes. Anthracene, acridine, and carbocyanine-based chromophores have been examined for their DNA binding properties and photo-reactivities. Their planar aromatic structures make them ideal chromophores that can be used to probe DNA structural interactions and binding patterns. We have studied DNA binding and photocleavgage properties of a bisacridine chromophore joined by a 2,6-bis(aminomethyl)pyridine copper-binding linker (Chapter II), a series of 9-aminomethyl anthracene chromophores (Chapters III and IV), both under conditions of high and low ionic strength, as well as a series of pentamethine linked symmetrical carbocyanine dyes (Chapter V). In Chapter II we present data showing that high ionic strength efficiently increases copper(II)-dependent photocleavage of plasmid DNA by the bisacridine based chromophore (419 nm, pH 7.0). In Chapters III and IV, using an pyridine N-substituted 9-(aminomethyl)anthracene (Chapter III), a bis-9-(aminomethyl)anthracene, and its mono 9-(aminomethyl)anthracene analogue (Chapter IV), pUC19 plasmid DNA was photo-converted to highly diffuse DNA fragments (350 nm, pH 7.0) in the presence of 150 mM NaCl and 260 mM KCl. Spectroscopic analyses suggest that the combination of salts promotes a change in DNA helical structure that initiate a switch in anthracene binding mode from intercalation to an external or groove binding interactions. The alteration in DNA structure and binding mode leads to an increase in the anthracene-sensitized production of DNA damaging reactive oxygen species. Finally, in Chapter V, pUC19 plasmid DNA is converted to its nicked circular and linear forms following irradiation of a series of pentamethine linked symmetrical carbocyanines (red light, pH 7.0). The data suggest that the relative levels of photocleavage arise from the different substituents on the nitrogen alkyl side chain and the pentamethine linker.

Page generated in 0.0565 seconds