• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 322
  • 293
  • 68
  • 39
  • 35
  • 15
  • 8
  • 7
  • 5
  • 3
  • 2
  • 2
  • 2
  • 1
  • 1
  • Tagged with
  • 972
  • 324
  • 253
  • 125
  • 86
  • 86
  • 81
  • 80
  • 73
  • 71
  • 62
  • 58
  • 56
  • 54
  • 52
  • 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.
31

Biogeochemistry of mycosporine-like amino acids (MAAs) : a new perspective on UV-absorbing compounds via liquid chromatography-mass spectrometry /

Whitehead, Kenia Luz. January 2002 (has links)
Thesis (Ph. D.)--University of Washington, 2002. / Vita. Includes bibliographical references (p. 121-130).
32

Determination of DDT and Metabolites in Surface Water and Sediment Using LLE, SPE, ACE and SE

Sibali, LL, Okonkwo, JO, Zvinowanda, C 09 April 2009 (has links)
Abstract Surface water and sediment samples collected from Jukskei River in South Africa, were subjected to different extraction techniques, liquid–liquid (LLE), solidphase extraction (SPE), activated carbon extraction (ACE) and soxhlet extraction (SE) for sediment. The samples were extracted with dichloromethane, cleaned in a silica gel column and the extracts quantified using a Varian 3800 GC-ECD. The percentage recovery test for 2,40DDT, DDE and DDD and 4,40DDT, DDE and DDD in water ranged from 80%–96% and 76%–95% (LLE); 56%–76% and 56%–70% (SPE) and 75%–84% (ACE), respectively; while that recoveries for sediment samples varied from 65%– 95% for 2,40DDT, DDE and DDD and 80%–91% for 4,40DDT, DDE and DDD. The high recoveries exhibited by ACE compared very well with LLE and SE. This was not the case with SPE which exhibited the lowest value of recoveries for both 2,4 and 4,40DDD, DDE and DDT standard samples. The mean concentrations of DDT and metabolites ranged from nd-1.10 lg/L, nd-0.80 lg/L, nd- 1.21 lg/L and 1.92 lg/L for LLE, SPE, ACE and SE, respectively. The total DDT (2,40 and 4,40-DDT) in water and sediment samples ranged from 1.20–3.25 lg/L and 1.82–5.24 lg/L, respectively. The low concentrations of the DDT metabolites obtained in the present study may suggest a recent contamination of the river by DDT.
33

Physiology of a kerosine-oxidizing Penicillium

Herring, Craig Maynard, 1945- January 1970 (has links)
No description available.
34

Characterization of a Newly Synthesized Cysteinyl Leukotriene 2 Receptor Selective Antagonist Using Cell Based β-arrestin and Vascular Ear Permeability Assays in Mice

YAN, DONG 06 July 2011 (has links)
(hCysLT2R) based on a β-galactosidase complementation system. The EC50 values for LTC4 and LTD4 are consistent with previous literature values determined based on radio-labelling affinity assays for hCysLT2R. Activity of a synthetic analogue of LTC4, N-Methyl LTC4 (NMLTC4), gave an EC50 value of 8.5 nM. Also described in this thesis, is the synthesis of a cysLT2R selective antagonist, 3-{[(3- carboxycyclohexyl)amino]carbonyl}-4-{3-{4-(4-phenoxybutoxy)phenyl}- propoxy}benzoic acid. Through the in vitro assay system, this selective antagonist showed a dose-dependent inhibition (IC50 value of 86 nM) when CysLT2R was stimulated with 30 nM of LTD4. Both the selective agonist (NMLTC4) as well as the selective cysLT2R antagonist were also tested in vivo in a localized vascular ear inflammation assay. Results show NMLTC4 is able to promote vascular leakage through stimulation of cysLT2R, and this extravasation can be significantly attenuated by the cysLT2R antagonist. / Thesis (Master, Biochemistry) -- Queen's University, 2011-06-29 22:31:03.11
35

The chemical investigation of the leaf exudates of a number of East African Aloe species

Conner, John Martin January 1988 (has links)
No description available.
36

Sphingosine 1-phosphate signalling in guinea pig airway smooth muscle

Kong, Kok Choi January 2002 (has links)
No description available.
37

Biosynthesis and translocation of secondary metabolite glycosides in the grapevine Vitis vinifera L. /

Gholami, Mansour. January 1996 (has links) (PDF)
Thesis (Ph. D.)--University of Adelaide, Dept. of Horticulture, Viticulture and Oenology, 1996? / Copies of author's previously published articles inserted. Includes bibliographical references (leaves 121-144).
38

Modulation of vascular response by equol

Lau, Chin-tung. January 2008 (has links)
Thesis (M. Res.(Med.))--University of Hong Kong, 2008. / Includes bibliographical references (p. 83-98)
39

Identification and characterization of odorous metabolites produced by selected freshwater algae /

Rashash, Diana M. C. January 1994 (has links)
Thesis (Ph. D.)--Virginia Polytechnic Institute and State University, 1994. / Vita. Abstract. Includes bibliographical references (leaves 191-203). Also available via the Internet.
40

Isolation of marine metabolites from S̲y̲m̲b̲i̲o̲d̲i̲n̲i̲u̲m̲ species of dinoflagellates /

Drainville-Higgins, Katherine Evelyn. January 2004 (has links)
Thesis (Ph. D.)--University of Rhode Island, 2004. / Typescript. Includes bibliographical references (leaves 339-347).

Page generated in 0.0585 seconds