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Histochemical Characterization of Lymphocytes in Preleukemic and Leukemic AKR Mice

Description: The AKR strain of mice have a genetic trait for spontaneous development of lymphocytic leukemia. In this study, leukemic mice were found to have significantly larger (p<0.01) thymuses and spleens than preleukemic mice. The enlarged leukemic tissues were densely packed with a light staining cell, with a hollow-appearing nucleus. Tissues from preleukemic mice were observed to be infiltrated with a smaller, darker-staining lymphocyte. Fluorescent antibody staining was done on preleukemic and leuke… more
Date: May 1979
Creator: Michnoff, Carolyn A.
Item Type: Refine your search to only Thesis or Dissertation
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Effect of Operant Behavior on the Metabolism of 5-Hydroxytryptamine

Description: The role of operant behavior in the metabolism of brain 5-hydroxytryptamine (5-HT) turnover was investigated. Two and one-half hours following the administration of 150 mg/kg of para-chlorophenylalanine (PCPA), a specific inhibitor of tryptophan hydroxylase, levels of 5-HT were compared in sedentary and performing rats. Whole brain levels of serotonin were reduced in both responding and sedentary animals; however, differences between these groups were not statistically significant. The drug ind… more
Date: August 1979
Creator: Shepard, Paul
Item Type: Refine your search to only Thesis or Dissertation
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Cigarette Residues Affect Steroidogenesis in Cultured Y-1 Mouse Adrenal Tumor Cells

Description: This study (1) quantitatively compared steroid production in cultured Y-l mouse adrenal tumor cells exposed to Camel and Carlton-smoke derived residues, and (2) localized the effects in the cell. Basal steroid production was increased by Camel residues but not by Carlton, while ACTH stimulation was interfered with by both residues. Camel basal stimulation was comparable to that of cAMP, and was abolished by Cytochalasin D. The stimulation was also comparable to that of cholera toxin, which acti… more
Date: December 1979
Creator: Morris, Paula D.
Item Type: Refine your search to only Thesis or Dissertation
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Genic Differentiation Between Two Chromosomal Races of Pocket Gophers, Geomys bursarius

Description: Genic data from two chromosomal races of Geomys bursarius from a contact zone in central Texas indicated that the two races possessed distinct gene pools which would define them as separate species. Data from proteins encoded from 21 loci in this study substantiated this hypothesis. A pattern of alternately fixed alleles at the ADH-l, MDH-2, LDH-l, and IDH-1 loci with no apparent gene flow in zones of contact strongly suggested that these two races should be designated as separate species. Leve… more
Date: May 1980
Creator: Bohlin, Raymond G.
Item Type: Refine your search to only Thesis or Dissertation
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Seasonal and Spatial Variability of the Microcrustacean Community in Lake Texoma, Texas and Oklahoma

Description: Twenty-eight species of zooplankton were identified from Lake Texoma. Seasonal density of the overall microcrustacean community and seasonal cycles of individual species were compared with northern populations and any available literature from the Southwest. Cycles of occurrence and abundance were similar to those observed in northern populations but tended to occur earlier in the year due to higher temperatures. Spatial distributions within the reservoir were heavily influenced by nutrient and… more
Date: August 1980
Creator: Crist, Lawrence W.
Item Type: Refine your search to only Thesis or Dissertation
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The Physiology of Azotobacter Vinelandii Cysts

Description: The value of the adenylate energy charge [(ATP)+1/2(ADP)/(ATP)+(ADP)+(AMP)] in Azotobacter vinelandii cells was monitored during growth and germination in flask cultures. The miximal value of 0.88 was attained during mid-log phase; this declined gradually to 0.50 by late stationary phase. When these cultures were transferred to encystment media, the adenylate energy charge decreased to an average value of 0.40 as the vegetative cells encysted and remained unchanged during the next 20 days. Ency… more
Date: December 1980
Creator: Aladegbami, Solomon L.
Item Type: Refine your search to only Thesis or Dissertation
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Taxonomy of the Azotobacteraceae

Description: The classification of the Azotobacteraceae to the level of genus and species has been uncertain since the studies of Beijerinck in 1901. This dissertation represents an effort to establish a system of classification more complete than the one now in use. In this study, both qualitative and quantitative taxonomy were used in order to establish a well founded classification scheme. Qualitative methods included certain important morphological and physiological characteristics, isoenzyme patterns, … more
Date: December 1980
Creator: Chang, Charles Shing
Item Type: Refine your search to only Thesis or Dissertation
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Enhancement by Human Chorionic Gonadotropin of Transformation of Chick Embryo Fibroblasts and Rat Kidney Cells Infected with Temperature-Sensitive and Wild Type Rous Sarcoma Viruses

Description: Human chorionic gonodotropin (HCG) affected in various ways cell cultures infected with strains of Rous sarcoma virus (RSV). The cell cultures studied were chick embryo fibroblasts (CEF), normal rat kidney cells infected with temperature-sensitive mutant (LA31-NRK) and a wild type RSV (B77-NRK). HCG increased the rate of transformation and viral titer of CEF cells infected with RSV, but not B77-NRK. HCG increased significantly transformation rates of LA31-NRK, only if the temperature sensitive … more
Date: August 1981
Creator: Mitchell, Monte Mark
Item Type: Refine your search to only Thesis or Dissertation
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Population Dynamics of Macrobenthos in a Regulated Stream 1970-71 and 1978

Description: Stability of the macrobenthic community in a regulated section of the Brazos River, Texas, was evaluated. Physicochemical data and information on spatial distribution of macrobenthos were collected. Populations of two invertebrate species, Isonychia sicca and Neoperla clymene, had been greatly reduced since 1970-71 and I. sicca had been practically eliminated from this section of the Brazos. Three other insect populations, Choroterpes mexicanus, Cheumatopsche campyla and Cheumatopsyche lasia, h… more
Date: August 1981
Creator: Coulter, James D. (James Duard)
Item Type: Refine your search to only Thesis or Dissertation
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Responses of Fishes to a Low pH Environment

Description: Data were collected from natural and introduced fishes present in Ferndale Lake, a small (120 ha) sport fishing reservoir in Camp County, east Texas. Levels of pH measured in the lake during the study period ranged from 3.5 to 5.3. Monthly field surveys and experimental manipulations were designed to evaluate quantitatively the signs of stress at various biological levels. Lethal limits to low pH were quantified for largemouth bass (Micropterus salmoides) and bluegill (Lepomis macrochirus) to b… more
Date: August 1981
Creator: Prete, Philip J. (Philip John)
Item Type: Refine your search to only Thesis or Dissertation
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Lizard Tail Autotomy: Some Aspects of its Ecology and Energetics

Description: Autotomy (self-induced loss) of body parts has evolved independently as a predator defense mechanism in several major animal phyla. The mechanism among vertebrates, including 13 of the 20 recognized lizard families, is tail autotomy. Its occurrence among the majority of lizard families offers an excellent opportunity to examine the effects of a major selective force on the ecology and evolution of a group of organisms. The research of this study was designed to examine experimentally (i) the fu… more
Date: December 1981
Creator: Dial, Benjamin Edward
Item Type: Refine your search to only Thesis or Dissertation
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Microbiological Studies of Biological Activated Carbon Filters Used in Water Treatment

Description: A collaborative pilot study of the microflora on biological activated charcoal (BAC) filters employed in the tertiary treatment of drinking water revealed the principle bacterial genera to be Pseudomonas, Alcaligenes, Achromobacter, Bacillus, Micrococcus, Corynebacterium, Chromobacterium, Microcyclus and Paracoccus. The microbial population of the filters paralleled seasonal carbon dioxide production. Of particular interest were the effects of the BAC miroorganisms upon precursors of trihalomet… more
Date: December 1981
Creator: Chang, Eichin
Item Type: Refine your search to only Thesis or Dissertation
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The Roles of Genic Behavioral and Biochemical Mechanisms in the Adaption of Minnows of the Genus Notropis (Cyprinidae) to Temperature

Description: Electrophoretic variation at twenty gene loci, patterns of behavioral thermoregulation, and genotype-specific malate dehydrogenase kinetics were investigated among populations of the red shiner, Notropis lutrensis, and the blacktail shiner, N. venustus, collected from thermally altered and thermally unaltered portions of their ranges. Genic variation was found to be high among red shiners and low among blacktail shiners. The behavioral response of the blacktail shiner to temperature was fixed a… more
Date: December 1981
Creator: Calhoun, Stuart W. (Stuart Wayne)
Item Type: Refine your search to only Thesis or Dissertation
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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
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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
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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
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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
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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
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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
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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
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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
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The Effect of Human Alpha Interferon on Rat Kidney Cell Infected with Temperature-Sensitive Mutant of Rous Sarcoma Virus

Description: LA31-NRK and B77-NRK are established cell lines that were normal rat kidney cells transformed with temperature-sensitive mutant (LA31) and wild-type Bratislava 77 (B77) of Rous sarcoma virus. It is recognized that many transformation-induced changes differentiate between normal and transformed cells. Morphology and four parameters of transformed cells such as saturation density, anchorage independence, plasminogen activator, and colony stimulating factor were used as indicators to observe the e… more
Date: May 1983
Creator: Chang, Shiuan
Item Type: Refine your search to only Thesis or Dissertation
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Comparative Feeding Ecology of Leaf Pack-Inhabiting Systellognathan Stoneflies (Plecoptera) in the Upper Little Missouri River, Arkansas

Description: The feeding ecologies of leaf pack-associated systellognathan stoneflies were examined from 6 June 1980 21 May 1981. Species composition, seasonal abundance, nymphal growth, feeding habits and mouthpart morphology were determined for the eight dominant stonefly species. Prey preferences and predator-prey size relationships were also examined for omnivorous and carnivorous species. Foregut analysis from 2860 individuals indicated opportunistic feeding on the most abundant prey insects, usually i… more
Date: August 1983
Creator: Feminella, Jack W. (Jack William)
Item Type: Refine your search to only Thesis or Dissertation
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The Effects of Freshet Turbidity on Selected Aspects of the Biogeochemistry and the Trophic Status of Flathead Lake, Montana U.S.A.

Description: The present study sought to falsify three distinct hypotheses about how the interactions of freshet clay turbidity with Flathead Lake may be affecting its trophic state: 1) that freshet-derived turbidity causes precipitation of organic detritus from the water column by flocculation and/or coagulation of dissolved and colloidal organic carbon and seston; 2) that flocculated clay-organic detritus complexes become increasingly infested with microbial biomass as they sink through the water column; … more
Date: August 1983
Creator: Stuart, Tom J.
Item Type: Refine your search to only Thesis or Dissertation
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