UNT Libraries - 8 Matching Results

Search Results

Results: 1 - 8
open access

Effects of Aging on ACTH-Stimulated Steroidogenesis in Subcellular Fractions from Rat Adrenal Glands

Description: Young, middle-aged and old rat adrenal gland steroidogenesis was measured in isolated, superfused glands and in their subcellular fractions before and after adrenocorticotropic hormone treatment. In the latter experiment, five corticosteroids were extracted from six different subcellular fractions. Superfused glands initially produced relatively high glucocorticoid levels; thereafter, production decayed asymptotically. Steroidogenesis by young and middle-aged glands was maintained at least 1.5 … more
Date: August 1982
Creator: Sawada, Tadao
Item Type: Refine your search to only Thesis or Dissertation
open access

The Growth of Azotobacter vinelandii on p-Hydroxybenzoic Acid from Soil Medium

Description: The purpose of this study was to search for the substrates utilized by Azotobacter vinelandii in dialysed soil media. Also, we sought to determine the relationship between these substrates and the growth and morphological variations of A. vinelandii. p-Hydroxybenzoic acid was shown to be used as the carbon and energy source by A. vinelandii in dialysed soil medium. The amount of this compound in the soil dialysed soil medium ranged from 14 to 21 micrograms per gram of soil. In a dialysed soil m… more
Date: August 1982
Creator: Wu, Fang Jy
Item Type: Refine your search to only Thesis or Dissertation
open access

The Influence of Stream Regulation on Genic Differentiation and Thermal Tolerance in the Red Shiner, Notropis Lutrensis

Description: Genetic variation and thermal tolerance were surveyed for variation attributed to nonuniform selection pressures for five populations of the red shiner, Notropis lutrensis, collected from regulated and unregulated portions of a Texas river. Populations within 30 km of a hypolimnion-release dam that experience large thermal perturbations were found to have higher levels of heterozygosity, higher levels of polymorphism, significantly depressed levels of upper thermal tolerance endpoints, and grea… more
Date: December 1982
Creator: King, Timothy L. (Timothy Lee)
Item Type: Refine your search to only Thesis or Dissertation
open access

The Effect of Intermediate Filament Inhibitors on Steroidogenesis and Cytoskeleton in Y-1 Mouse Adrenal Tumor Cells

Description: When Y-1 mouse adrenal tumor cells were treated with sodium orthovanadate, an intermediate filament (IF) inhibitor in BHK21-F cells, there was no change in the amount of 20α-dihydroprogesterone produced. A neurofilament inhibitor, β, β'-iminodipropionitrile (IDPN), enhanced the ability of Y-1 cells to produce steroid in response to ACTH by acting on the plasma membrane. Electron microscopy of Y-1 cells extracted with Triton X-100 revealed that both vanadate and IDPN caused the aggregation of cy… more
Date: August 1982
Creator: Lee, Hyun Sook
Item Type: Refine your search to only Thesis or Dissertation
open access

Effects of Exogenous Steroids on the Adrenal Plasma Membrane Alteration of Steroidogenesis and Cell Morphology

Description: Using cultured Y-1 mouse adrenal tumor cells which produce the steroid 20(-hydroxypregn-4-en-3-one (20-DHP), it was found that 10-5 M corticosterone and deoxycorticosterone increased basal and inhibited ACTH-induced 20-DHP production. The steroid effects were concentration-dependent, reversible, and specific since six other steroids did not stimulate steroidogenesis and varied in their ability to inhibit ACTH-induced steroidogenesis. Cytochalasin D inhibited steroid-stimulated 20-DHP production… more
Date: August 1982
Creator: Mattson, Mark Paul
Item Type: Refine your search to only Thesis or Dissertation
open access

Postsynthetic Modifications of Glycolytic Enzymes of the Geriatric Immune System and in Fibroblasts from Premature Aging Diseases

Description: During mitogen-induced transformation of human lymphocytes, phosphoglycerate kinase (PGK) exhibits new electrophoretic forms (pl=8.5-8.9). Electrophoresis and electrofocusing showed that the new forms are not due to expression of the autosomally linked isozyme found in semen (PGK-B; pl=9.7). The multiple electrophoretic forms are the result of protease modification of sex-linked PGK-A isozyme.When peripheral lymphocytes from young persons are stimulated in vitro with phytohemagglutinin, a selec… more
Date: August 1982
Creator: Tollefsbol, Trygve O.
Item Type: Refine your search to only Thesis or Dissertation
open access

Chemically Active Odorants as Olfactory Probes

Description: The initial step in odor recognition by the nose is the binding of odorant molecules to receptor sites embedded in the dendritic membranes of olfactory receptor cells. Despite considerable interest and experimentation into the nature of these receptor sites, little is known of their specificity to different types of odorant molecules. This lack of knowledge partially stems from the fact that the nature of receptor proteins is most effectively studied when specific and irreversible inhibitors ar… more
Date: May 1982
Creator: Criswell, Darrell W. (Darrell Wayne)
Item Type: Refine your search to only Thesis or Dissertation
open access

Lethal and Sublethal Effects of Hemoxidants, Particularly Nitrite, on Selected Aquatic Animals

Description: A research program was developed to investigate basic and applied aspects of toxicity, both lethal and sublethal, of hemoxidants, particularly nitrite, on fish, non-fish aquatic vertebrates, and crayfish. The major objectives of this research were to determine A) acute and sublethal toxicity of nitrite to selected aquatic organisms: 1. aquatic salamander larvae, Ambystoma texanum, 2. swamp crayfish, Procambarus simulans, 3. bluegill, Lepomis macrochirus, 4. bullfrog, tadpoles, Rana catesbiana, … more
Date: May 1982
Creator: Huey, David W. (David Worley)
Item Type: Refine your search to only Thesis or Dissertation
Back to Top of Screen