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The Immune Response of Guinea Pigs as Influenced by Hypobaric Pressure and Normoxic Environment (Part I); Membrane Filter-Fluorescent-Antibody Method for Detection and Enumeration of Bacteria in Water (Part II)

Description: In this work experimental design and tests were established to determine whether antibody production in guinea pigs injected with a bacterial antigen is Influenced by the environment of simulated high altitude with normoxic conditions. Hematological and electrophoretic studies were simultaneously run with the antibody determinations as a check on related responses of the animals.
Date: August 1969
Creator: Reeder, Dennis James
Partner: UNT Libraries
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Selected Physiological and Biochemical Studies on Blue-Green Algae

Description: Twenty-two different unialgal clonal isolates have been obtained at random for experimental purposes over a period of about one year. Also, during this period, at least 12 other species or strains have been isolated into unialgal cultures which had not yet been identified and/or significantly cleared of heterotrophic contaminants.
Date: August 1969
Creator: Wyatt, Jimmy T. (Jimmy Trueman), 1922-
Partner: UNT Libraries
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Food, Feeding Selectivity, and Ecological Efficiencies of Fundulus notatus (Rafinesque) (Osteichthyes; Cyprinodontidae)

Description: This study was made to further define the trophic dynamics of Fundulus notatus by determining its ration composition under natural conditions, measuring feeding selectivity under various laboratory conditions of prey-species composition and availability, and determining the efficiencies with which F. notatus utilizes ingested chironomid larvae.
Date: August 1970
Creator: Atmar, Gerald Legare
Partner: UNT Libraries
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Light and Electron Microscope Studies on the Chemotherapeutic Effect of a Combination of Dimethyl Sulfoxide and Hematoxylin on a Transplantable Lymphosarcoma

Description: Investigations concerning the cellular response of tumor tissue to treatment with dimethyl sulfoxide and hematoxylin have not been reported. To establish the response of neoplastic tissue and cells to this combination of agents, this study was undertaken to determine the effects of dimethyl sulfoxide and hematoxylin on a transplantable lymphosarcoma in mice.
Date: January 1970
Creator: Rogers, Thomas D., 1939-
Partner: UNT Libraries
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Serological Characterization of Members of the Genus Streptomyces

Description: This investigation involved isolation and characterization of specific antigenic materials from known species of Streptomyces. The resulting antigens were then used to establish serological relationships between a number of different species. These groupings were, in turn, compared with similar studies recently established by the ISP, in which other taxonomic criteria were used. By these means, the serological characteristics of the Streptomyces were evaluated for their potential utility as add… more
Date: August 1968
Creator: Taylor, Gerald Roger
Partner: UNT Libraries
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Polycyclic-Aromatic-Hydrocarbon-Induced Alterations in the Physio-Chemical Characteristics of Escherechia Coli Dexyribonucleic Acid

Description: Prior to 1965 the interactions of polycyclic aromatic hydrocarbons with DNA (Deoxyribonucleic acid) had been but moderately studied. It was concluded that, although a controversy existed, an apparent interaction occurred between DNA and certain aromatic hydrocarbon molecules and that the interaction was not an artifact of the reaction system.
Date: August 1969
Creator: Chapel, J. Frederick (James Frederick)
Partner: UNT Libraries
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Effects of Carbaryl (1-Naphthyl-n-methylcarbamate) on Trichocorixa Reticulata (Hemiptera: Corixidae) and Glyptotendipes Barbipes (Diptera: Chironomidae)

Description: My study of the effects of carbaryl in aquatic systems under controlled laboratory conditions emphasized four major objectives: (1) to determine the acute toxicity of carbaryl to the herbivorous adult and immature Trichocorixa reticulata (Guerin)(Hemiptera: Corixidae), and to the omnivorous larvae of Glyptotendipes barbipes (Staeger) (Diptera: Chironomidae) under static bioassay; (2) to adapt a quantitative method of analysis for carbaryl in water and whole insect tissue extract; (3) to measure… more
Date: December 1971
Creator: Gash, Stephen L.
Partner: UNT Libraries
open access

Effects of Peripheral Nerve Injury on the Cells of the Dorsal Root Ganglion: a Role for Primary Cilia

Description: Primary cilia are ubiquitous sensory organelles found on most cell types including cells of the dorsal root ganglia (DRG). The DRG are groups of peripheral neurons that relay sensory information from the periphery to the CNS. Other cell types in the DRG include a type of glial cell, the satellite glial cells (SGCs). The SGCs surround the DRG neurons and, with the neurons, form functional sensory units. Currently are no reports describing the numbers of DRG cells that have cilia. We found tha… more
Date: December 2012
Creator: Smith, Sarah K.
Partner: UNT Libraries
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Aging Is a Determinant in Anoxia Stress Tolerance in Caenorhabditis Elegans

Description: Oxygen availability is critical for survival for most organisms. The nematode, C. elegans, has been useful for studying genetic regulation of anoxia tolerance due to the oxygen deprivation response mechanisms shared with other metazoans. Studies examining long-term anoxia (72h, LTA) tolerance have only been conducted at adult day 1. To investigate the effect of aging on anoxia tolerance wild-type and mutant strains were exposed to LTA between adult day 1 and day 9. Wild-type isolates and daf-16… more
Date: May 2013
Creator: Goy, Jo M.
Partner: UNT Libraries
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Enzyme Assays Using Earthworms for Assessing Innate and Nonspecific Immunotoxicity of Xenobiotics

Description: Principal objectives of my research were to: (1) report for the first time that coelomocytes are able to reduce NBT dye and confirm the presence of lysozyme-like activity in earthworm; (2) develop a standard methodology for determination of NBT reduction and lysozyme-like activity in earthworms; (3) compare NBT reduction and lysozyme-like activity in earthworms with those of murine and human cells and fluids; and (4) demonstrate the sensitivity of earthworm NBT reduction and lysozyme-like activ… more
Date: May 1992
Creator: Chen, Shing-Chong
Partner: UNT Libraries
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Regulatory Divergence of Aspartate Transcarbamoylase from the Pseudomonads

Description: Aspartate transcarbamoylase (ATCase) was purified from 16 selected bacterial species including existing Pseudomonas species and former species reassigned to new genera. An enormous diversity was seen among the 16 enzymes with each class of ATCase being represented. The smallest class, class C, with a catalytically active homotrimer, at 100 kDa, was found in Bacillus and other Gram positive bacteria. In this report, the ATCases from the Gram negatives, Shewanella putrefaciens and Stenotrophomona… more
Date: December 1996
Creator: Linscott, Andrea J. (Andrea Jane)
Partner: UNT Libraries
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Primary Productivity and Nutrient Relationships in Garza-Little Elm Reservoir

Description: A large, multi-basin, reservoir (Garza-Little Elm Reservoir) in north central Texas was studied to determine the relative effects of various parameters on primary productivity. The basins were impounded several years apart,thus allowing the influence of age on water chemistry and biota to be considered. Another principal influence on water quality was secondary sewage effluent that entered one basin from a nearby source.
Date: May 1973
Creator: Smith, Jerry Allen
Partner: UNT Libraries
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Physiological Ecology, Population Genetic Responses and Assemblage Stability of Fishes in Two Southwestern Intermittent Stream Systems

Description: Six sites within the Denton and Hickory Creek watersheds were sampled over three years to assess the impact of seasonal intermittent stream conditions on the ichthyofauna. An integrated approach using field and laboratory techniques was employed to evaluate the responses of the fishes.
Date: December 1991
Creator: Rutledge, Charles Jerry, 1941-
Partner: UNT Libraries
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Biodiversity of Caddisflies (Trichoptera) of the Interior Highlands of North America

Description: Caddisflies (Trichoptera) were collected from over 500 different locations throughout the Interior Highlands (Ozark, Ouachita, Arbuckle, and Wichita Mountains) between March 1990 and March 1994. I systematically sampled representative lotic and lentic habitats in 131 natural watersheds that comprise the 17 different physiographic subregions of this area. From my examination of approximately 60,000 specimens, surveys of regional museum collections, and review of literature records, I document 22… more
Date: August 1994
Creator: Moulton, Stephen R. (Stephen Richard)
Partner: UNT Libraries
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Landscape Ecological Characteristics of Habitat of the Red-cockaded Woodpecker

Description: Geographic information systems (GIS) technology was used to analyze factors influencing habitat use by an endangered species, the red-cockaded woodpecker. The study area was the western part of the Raven Ranger District of the Sam Houston National Forest, Texas. The factors considered included both structural characteristics and spatial relationships among stands of trees in the habitat.
Date: December 1993
Creator: Thomlinson, John Richard
Partner: UNT Libraries
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Isolation, Characterization and Physiological Studies of Cyanide-Utilizing Bacteria

Description: Ten bacteria capable of growth on the metal-cyano complex, tetracyanonickelate (II) {K2 [Ni(CN)J } (TCN), supplied as the sole nitrogen source, were isolated. Seven isolates were identified as pseudomonads while the remaining three were classified as Klebsiella species. In addition to TCN, all isolates were able to utilize KCN although it was significantly more toxic. The degradation of TCN was most complete when supplied at growth-limiting concentrations, did not occur when ammonia was present… more
Date: December 1991
Creator: Silva Avalos, Juan G. (Juan Guillermo)
Partner: UNT Libraries
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Discovery and Characterization of Two Tn5 Generated pyrA Mutants in Pseudomonas putida and the Generation of Hfr Strains

Description: A pyrA mutation in Pseudomonas putida was isolated using transposon mutagenesis for the first time. Transposon Tn5 was used to inactivate the pyrA gene for carbamoylphosphate synthetase in these mutants. Accordingly, these mutants were defective in pyrimidine and arginine biosynthesis. The suicide vector, pM075, from Pseudomonas aeruginosa, was used to introduce the transposon into the cells. Tn5 was subsequently used to supply homology so that the plasmid pM075 could be introduced in its entir… more
Date: August 1994
Creator: Liljestrand, Laura Gail
Partner: UNT Libraries
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Alterations in Human Baroreceptor Reflex Regulation of Blood Pressure Following 15 Days of Simulated Microgravity Exposure

Description: Prolonged exposure to microgravity is known to invoke physiological changes which predispose individuals to orthostatic intolerance upon readaptation to the earth's gravitational field. Attenuated baroreflex responsiveness has been implicated in contributing to this inability to withstand orthostatic stress. To test this hypothesis, eight individuals were exposed to 15 days of simulated microgravity exposure using the 6° head-down bed rest model. Prior to, and after the simulated microgravity e… more
Date: August 1993
Creator: Crandall, Craig G. (Craig Gerald)
Partner: UNT Libraries
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Pyrimidine Salvage Enzymes in Microorganisms: Labyrinths of Enzymatic Diversity

Description: Pyrimidine salvage pathways are essential to all cells. They provide a balance of RNA synthesis with the biosynthetic pathway in pyrimidine prototrophs and supply all the pyrimidine requirements in auxotrophs. While the pyrimidine biosynthetic pathway is found in almost all organisms and is nearly identical throughout nature, the salvage pathway often differs from species to species, with aspects of salvage seen in every organism. Thus significant taxonomic value may be ascribed to the salvage … more
Date: December 1995
Creator: Beck, Debrah A. (Debrah Ann)
Partner: UNT Libraries
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The Eosinophil Response in Mice Infected with Trichinella spiralis or Trichinella pseudospiralis as Indicated by Phospholipase B Activity

Description: The host eosinophil response was compared in mice infected with either T. spiralis or T. pseudospiralis by determination of levels of splenic and intestinal phospholipase B, a marker enzyme for eosinophils. Primary infection of naive mice and challenge infection of homologously sensitized mice with T. pseudospiralis resulted in significantly lower tissue phospholipase B activities than infection with T. spiralis. Mice homologously challenged with T. pseudospiralis did exhibit an anamnestic eosi… more
Date: December 1992
Creator: Hsu, Shing-Chien
Partner: UNT Libraries
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