UNT Theses and Dissertations - 7 Matching Results

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Diphenyloxazole Metabolism by Aryl Hydrocarbon Hydroxylase

Description: 2,5-Diphenyloxazole (PPO) was tested as a potential alternate inducer for the aryl hydrocarbon hydroxylase (AHH) system. Its apparent lack. of carcinogenicity and toxicity provide a possible system for investigation of enzyme systems related to chemical carcinogenesis without exposure of the researcher to potent carcinogenic compounds. These studies found PPO to be an inducer of AHH in cultured human lymphocytes. When PPO was utilized as a substrate for the AHH assay system, the major metabolit… more
Date: December 1976
Creator: Abreu, Mary E.
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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The Dynamics of a Planktonic Microcrustacean Community in a Small North Central Texas Pond Ecosystem

Description: Seven species of planktonic microcrustacea were identified from the North Texas State University Golf Course Pond. Total adult microcrustacean community density, biomass and biocontent, and seasonal cycles of each species were compared with northern populations. Species diversity and evenness indices were highest in summer and lowest in spring. Variations in microcrustacean density showed a positive correlation with density of phytoplankton. Temperature had a direct effect on metabolic rates of… more
Date: December 1976
Creator: Smith, George Arthur
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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The Hypothermic Perfusion of the Isolated Thyroid Gland and Its Release of T₃ And T₄

Description: Investigations have shown that the hypothalamus and pituitary respond to decreases in body temperature by stimulating thyroid release of T_3 and T_4 . This study was designed to bypass the control of the hypothalamus and pituitary gland and investigate the direct effect of temperature on the thyroid gland. Hypothermia was by an in vivo isolated perfusion of the thyroid gland. Radio-immunoassay was used to measure T_3 and T_4 concentrations. Significant increases were observed in animals perfuse… more
Date: December 1976
Creator: Haenke, Richard F.
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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Life History Allocation of Energy to Growth and Reproduction in Gizzard Shad, Dorosoma cepedianum, in North Central Texas

Description: Life history allocation of energy to growth and reproduction was determined for female gizzard shad. Absolute caloric energy allocated to eggs increased with age. The relative amount of production energy directed to reproduction increased with age up to 5 years and then decreased. Seasonal variation in lipids was studied. Quantitative changes occurred in ovarian lipids during the reproductive cycle. Carcass lipids varied seasonally. Age of sexual maturity was 3 years. Delayed maturity is attrib… more
Date: December 1976
Creator: Fagan, Joseph A.
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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Physiological Studies of the Bdellovibrio-Host Interaction

Description: The purpose of this study was to focus attention on the physiology of the bdellovibrio-host interaction and to determine the metabolic requirements for this reaction. Since bdellovibrio is an aerobic organism, direct measurements of respiration, turbidity, and viable cell counts are reliable indications of the metabolic activity of the cells. It was determined that the metabolic requirements for the parasitic interaction are constituents from either metabolically active host cells or cells whi… more
Date: December 1976
Creator: Dunton, Philip J.
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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Relationship of Certain Fungi to Azotobacter in Nitrogen-Free Media

Description: Azotobacter and various fungi were grown together in nitrogen-free media. Maximal fungal growth in the medium used was possible only at the expense of Azotobacter cells and growth was always accompanied by acid production. When the medium reached a pH of 2, the bacterial cells were aggregated on fungal hyphae and the culture fluid appeared to be free of Azotobacter. Aspergillus niger grew well at the expense of viable bacteria and other fungi grew well on heat-killed cells of A. vinelandii. Mem… more
Date: August 1976
Creator: Ray, Manfred G.
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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A Study of Aryl Hydrocarbon Hydroxylase in Cultured Human Lymphocytes

Description: Aryl hydrocarbon hydroxylase activity was studied in cultured human lymphocytes using 3-methylcholanthrene, 1,2- benzanthracene, and 4'-bromoflavone as inducers. The substrates used to run the 60 minute assay were benzo(α)pyrene and diphenyloxazole. At the optimum bromoflavone concentration for induction of aryl hydrocarbon hydroxylase, the induced enzymatic activity compared favorably with that of aryl hydrocarbon hydroxylase induced by 3MC in a 96 hour lymphocyte culture using BP as the assay… more
Date: August 1976
Creator: Guyden, Jerry C.
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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