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An Ecological Survey of the Herpetofauna of Palo Pinto County, Texas

Description: The purpose of this research was to compile a presence list of reptiles and amphibians that occur in Palo Pinto County, Texas, and to investigate the ecological distributions and zoogeographic affinities of these herpetiles. The study area was chosen primarily because of its location in North Central Texas and its rugged topography, which sets it apart from the surrounding area.
Date: August 1969
Creator: Porter, Stuart T.
Item Type: Refine your search to only Thesis or Dissertation
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Metabolism of Hydrocortisone by X-Irradiated Rat Liver Tissue as Determined by the Porter-Silber Chromagen Method

Description: The present study may be considered endocrinological and radiobiological in nature. The endocrinology phase was concerned with studying the changes in endocrine function following the application of a stress agent. X-irradiation was chosen as the stressor in order to determine any difference in effect of this stressor from others which have been studied, e. g. heat, cold, metabolic poisons. Liver slices taken from rats at various time intervals following whole body X-irradiation were tested for… more
Date: August 1959
Creator: Pryor, Nan Webb
Item Type: Refine your search to only Thesis or Dissertation

Studies on Tissue Factor Pathway Inhibitor in Zebrafish

Description: Tissue Factor Pathway Inhibitor (TFPI) is an anticoagulant protein containing three Kunitz domains, K1, K2 and K3. K1 inhibits Factor VIIa, K2 inhibits Factor Xa, and K3 enhances the Factor Xa inhibition by its interaction with Protein S. Since zebrafish is an excellent genetic model, we hypothesized that TFPI regulation could be studied using this model. As a first step, we confirmed the presence of tfpia in zebrafish. Subsequently, we performed knockdown of tfpia, and knockout of tfpia in K3 … more
Date: August 2021
Creator: Raman, Revathi
Item Type: Refine your search to only Thesis or Dissertation
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Effects of X-irradiation on Potassium Flux in Isolated Nerves

Description: The purpose of this study, therefore, was threefold in nature: (1) to determine the effects of x-irradiation on the influx and efflux of potassium in compound nerve fibers (2) to attempt to relate the radiation-induced changes in electrical activity with potassium flux and (3) to use the information obtained to gain insight into the possible cellular site (s) of radiation insult to compound nerves.
Date: August 1966
Creator: Ramsey, Christian Norman
Item Type: Refine your search to only Thesis or Dissertation
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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
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Effects of High Altitude Exposure on Capillary Permeability

Description: Observations of decreases in plasma volume, shifts in plasma and lymph protein concentrations, and increases in capillary permeability at high altitude have been reported in the literature by several investigators. This investigation was begun in an attempt to elucidate the possible significance of these phenomena in future space exploration, and because of the lack of knowledge concerning the underlying mechanisms. The purpose of this investigation was to determine the effects of exposure to … more
Date: December 1971
Creator: Reaves, Troy Albert
Item Type: Refine your search to only Thesis or Dissertation
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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
Item Type: Refine your search to only Thesis or Dissertation
open access

Antibiocity of the Oleoresins of One Hundred Texas Spermatophytes upon Twenty Gram-Positive Bacterial Organisms

Description: This investigation is concerned with the testing, in vitro, of oleoresins from one hundred higher plants common to North and South Central Texas. The plants used were selected in order to obtain a representative collection which might be of value in future research.
Date: 1949
Creator: Richardson, Lavon P.
Item Type: Refine your search to only Thesis or Dissertation
open access

The Effect of Media Constituents on Growth and Pigment Production of Mycobacterium Phlei, Pseudomonas Fluorescens, Pseudomonas Aeruginosa, and Staphylococcus Citreus

Description: Little is known concerning the production and significance of bacterial pigments. There is seemingly an open field for studying the effects produced by varying the nutritive content of culture media upon which organisms are grown. This has led to an especial interest in, and the purpose of this investigation.
Date: 1947
Creator: Robbins, Finis E.
Item Type: Refine your search to only Thesis or Dissertation
open access

Effects of Altitude on Pressure-Flow Relationships in the Vascular Bed of the Hind Limb of the Dog

Description: The purpose of this investigation was to study the effects of decreasing barometric pressure upon the pressure-flow relationships in a peripheral vascular bed in an attempt at better delineation of the autoregulatory mechanisms. A decrease in barometric pressure does influence the transmural pressure and could theoretically affect smooth muscle tone. An evaluation of the extent of the transmural effect is essential to understanding vascular dynamics at altitudes.
Date: August 1966
Creator: Roberts, Donald E.
Item Type: Refine your search to only Thesis or Dissertation
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Bacterial Survey of Representative Denton County Wells with Special Reference to Sanitation

Description: This thesis aimed to study the seventy-two representative wells of Denton County and to determine the possibilities of infection with typhoid organism. The sanitary survey and the test for Colon-Aerogenes bacteria show that 55% of the 72 wells studied are unsanitary, 27% are sanitary, and 18% are doubtful.
Date: June 1937
Creator: Roberts, Sally Stevens
Item Type: Refine your search to only Thesis or Dissertation
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The Histological Effects of Injections of Fish Pituitary Extracts on the Testes of Male Frogs, (Rana Pipiens), and the Reproductive System of Immature Mice

Description: The purpose of this investigation was first, to make a histological and cytological study of the testis of male frogs, Rana pipiens, and to determine if there were tissue or cellular changes as well as physiological effects caused by fish pituitary-extract injections. Second, to determine if injections of fish pituitary extract into immature female white mice caused histological changes in the ovaries and uteri.
Date: 1949
Creator: Robertson, William George
Item Type: Refine your search to only Thesis or Dissertation
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A Vegetative Key to the Grasses of Erath County, Texas

Description: "The orientation of this study began with a collection of the grasses of Erath County during their flowering periods. Collections were made in the Spring and Fall of 1950 and 1951 to obtain both vernal and autumnal grasses. Identifications were made from the grass floras previously mentioned and checked against specimens in the herbarium of North Texas State College for verification. In addition, the list was checked by W.A. Turney, Conservationist, United States Department of Agriculture of Du… more
Date: August 1951
Creator: Robinson, Inez Evans
Item Type: Refine your search to only Thesis or Dissertation
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Adenylate Energy Charge Determinations of Soil Bacteria Grown in Soil Extract Medium

Description: The adenylate energy charge values of twenty bacteria isolated from soil and cultured in a medium consisting of soil and distilled water were determined by the luciferin-luciferase bioluminescense method. The purpose of this study was to examine the growth and energy charge values of these organisms in soil extract medium, and to determine what effect the addition of glucose has on their energy charge values. Three of the organisms employed in this study showed energy charge values similar to t… more
Date: August 1988
Creator: Rodriguez, Luis A. (Luis Antonio)
Item Type: Refine your search to only Thesis or Dissertation
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