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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.
211

Dihydroxypropyl theophylline: its preparation and pharmacological and clinical study

Maney, Paul Vance 01 January 1945 (has links)
No description available.
212

SEMISYNTHETIC AURONES: A FAMILY OF NEWLY DISCOVERED TUBULIN INHIBITORS AS ANTINEOPLASTIC AGENTS

Xie, Yanqi 01 January 2019 (has links)
Aurones belong to an uncommon class of plant flavonoids that provide the bright yellow coloration of some ornamental flowers and that possess a range of biological activities. Structure-activity relationships (SAR) in the aurone pharmacophore identified heterocyclic variants of the (Z)-2-benzylidene-6-hydroxybenzofuran-3(2H)-one scaffold that possessed low nanomolar in vitro potency in cell proliferation assays using various cancer cell lines, in vivo potency in prostate cancer PC-3 xenograft and zebrafish models, selectivity for the colchicine-binding site on tubulin, and absence of appreciable toxicity. Among the biologically active analogs developed in the course of this dissertation work were (Z)-2-((2-((1-ethyl-5-methoxy-1H-indol-3-yl)methylene)-3-oxo-2,3-dihydrobenzofuran-6-yl)oxy)acetonitrile (5a) and (Z)-6-((2,6-dichlorobenzyl)oxy)-2-(pyridin-4-ylmethylene)benzofuran-3(2H)-one (5r). These two aurones 5a and 5r inhibited in vitro PC-3 prostate cancer cell proliferation with IC50 values below 100 nM. A xenograft study in nude mice using 10 mg/kg of 5a for 18 days had no effect on mice weight, and aurone 5a did not inhibit, as desired, the human ether-à-go-go-related (hERG) potassium channel. Cell cycle arrest data, comparisons of the inhibition of cancer cell proliferation by aurones and known antineoplastic agents, and in vitro inhibition of tubulin polymerization indicated that aurone 5a disrupted tubulin dynamics. Based on a National Cancer Institute COMPARE analysis, studies using computer-based molecular docking and liquid chromatography-electrospray ionization-tandem mass spectrometry studies, aurone 5a targets the colchicine-binding site on tubulin. In addition to solid tumors, aurones 5a and 5r strongly inhibited in vitro a panel of human leukemia cancer cell lines and the in vivo myc-induced T cell acute lymphoblastic leukemia (T-ALL) in a zebrafish model. In summary, aurones possess a pharmacophore of considerable potential in the search for new antineoplastic agents for the clinical treatment of human cancers.
213

Design and Synthesis of Novel Chloroquine-based Antimalarials

Murphy, Kevin Vincent 04 November 2015 (has links)
Malaria is an infectious, often fatal disease that afflicts nearly 200 million people every year. The disease, characterized by recurring and extreme flu-like symptoms, is caused by the protozoan parasite Plasmodium falciparum. Victims usually contract the disease through a mosquito vector. Chloroquine is a chemotherapeutic that was introduced in the 1940s. For many years the drug was the foremost treatment of malaria, being effective and producing few side effects. Unfortunately, tolerance to chloroquine developed when the parasite evolved a resistance mechanism. Newer drugs have been developed and implemented, but these medicines also show a decreasing effect with continued administration. It is imperative that a new pipeline of drugs be developed in order to combat the disease and anticipated resistance. Reversed chloroquines are a new class of multiple-ligand compounds that are active against chloroquine-sensitive and chloroquine-resistance malaria species. This thesis describes research targeted at the modification of lead reversed chloroquine molecules to discover new and effective moieties, as well as to improve pharmacokinetic-related properties. An especial emphasis of this project is the addition of a sulfonamide functional group to a reversed chloroquine. Preliminary evidence indicates that this is a promising direction for this line of research. Brief discussions of some reversed chloroquine characterization studies are included in appendices.
214

Synthesis of Non-Steroidal Estrogen Agonists for Hormone Replacement Therapy and Synthesis and Reactivity of 2,3-Substituted 5-Silyl-7-Oxa-Bicyclo[2.2.1]Heptenes and Heptadienes

Chkrebtii, Anna 07 February 2011 (has links)
The focus of the research described in this section of the thesis is the synthesis of compounds expected to bind strongly to both the estrogen β and α receptors and act as estrogen agonists. Based on earlier results in our group and docking studies we prepared a series of A-CD analogs, compounds 1, in which the usual 13-methyl group was replaced by an ethyl group. Docking studies also indicated that substituents at C8 could lead to enhancement of binding to the estrogen receptor. With this in mind two such derivatives, compounds 2 were prepared. A major concern in the use of estradiol in hormone replacement therapy is its potential metabolism of dangerous ortho-quinones. The 1,2-naphthalenediol derivatives 3 avoid this possibility. They were predicted to be potent binders to the estrogen receptors with the naphthalene diol portion serving as rings A and B and the hydroxyl group taking the place of the 17-OH group of estradiol. The preparation of several derivatives of 2 is reported. The estrogen receptor binding [ERB] relative to estradiol as standard has been determined at the University of Illinois for a number of the compounds prepared in this thesis. Unfortunately, the results were not as encouraging as expected. Importantly, all of the 13-ethyl derivatives tested showed lower binding affinity compared to the 13-methyl analogs. Similarly, the derivatives with substituents at C8 do not show higher activity than those having only hydrogens at C8. Finally, the situation with the naphthalene derivatives is, at this stage, still not completely resolved. The binding for the compounds thus tested is quite low, but it must be admitted that the structures thus far synthesized have a much lower LogP than estradiol, a factor known to greatly decrease the binding constants to the estrogen receptors.
215

Pharmacokinetic characterization of the main flavonoids in the extract of Scutellariae Radix / 黃芩水提物中主要黃酮類成份的藥代動力學研究

Cai, Yu January 2011 (has links)
University of Macau / Institute of Chinese Medical Sciences
216

Synthesis of Non-Steroidal Estrogen Agonists for Hormone Replacement Therapy and Synthesis and Reactivity of 2,3-Substituted 5-Silyl-7-Oxa-Bicyclo[2.2.1]Heptenes and Heptadienes

Chkrebtii, Anna 07 February 2011 (has links)
The focus of the research described in this section of the thesis is the synthesis of compounds expected to bind strongly to both the estrogen β and α receptors and act as estrogen agonists. Based on earlier results in our group and docking studies we prepared a series of A-CD analogs, compounds 1, in which the usual 13-methyl group was replaced by an ethyl group. Docking studies also indicated that substituents at C8 could lead to enhancement of binding to the estrogen receptor. With this in mind two such derivatives, compounds 2 were prepared. A major concern in the use of estradiol in hormone replacement therapy is its potential metabolism of dangerous ortho-quinones. The 1,2-naphthalenediol derivatives 3 avoid this possibility. They were predicted to be potent binders to the estrogen receptors with the naphthalene diol portion serving as rings A and B and the hydroxyl group taking the place of the 17-OH group of estradiol. The preparation of several derivatives of 2 is reported. The estrogen receptor binding [ERB] relative to estradiol as standard has been determined at the University of Illinois for a number of the compounds prepared in this thesis. Unfortunately, the results were not as encouraging as expected. Importantly, all of the 13-ethyl derivatives tested showed lower binding affinity compared to the 13-methyl analogs. Similarly, the derivatives with substituents at C8 do not show higher activity than those having only hydrogens at C8. Finally, the situation with the naphthalene derivatives is, at this stage, still not completely resolved. The binding for the compounds thus tested is quite low, but it must be admitted that the structures thus far synthesized have a much lower LogP than estradiol, a factor known to greatly decrease the binding constants to the estrogen receptors.
217

Herbal supplement education in dental hygiene curricula

Lisauckis, Lisa Elena, January 2002 (has links)
Thesis (M.S.)--West Virginia University, 2002. / Title from document title page. Document formatted into pages; contains viii, 63 p. : ill. (some col.). Vita. Includes abstract. Includes bibliographical references (p. 48-50).
218

Reproductive biology of medicinal woodland herbs indigenous to the Appalachians /

Albrecht, Matthew A. January 2006 (has links)
Thesis (Ph. D.)--Ohio University, 2006. / Includes bibliographical references. Also available in PDF format via the Internet.
219

A phytochemical study of Cnicus benedictus L. (Carduus benedictus)

Miller, Lawrence P. January 1926 (has links)
Thesis (M.S.)--University of Wisconsin, 1926. / Includes bibliographical references (p. 32-42) and index.
220

Investigation of (3-mercaptopropyl) trimethoxysilane (MPTS)-modified surface and DNA microarray for genotyping of traditional Chinese medicinal plants /

Cheung, Kin Lok. January 2003 (has links)
Thesis (M. Phil.)--Hong Kong University of Science and Technology, 2003. / Includes bibliographical references (leaves 103-111). Also available in electronic version. Access restricted to campus users.

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