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The Cytotoxic And Dna Damaging Effects Of Ethylcholine Mustard Aziridinium Ion (Af64a), Diane Marie Barnes Jan 1989

The Cytotoxic And Dna Damaging Effects Of Ethylcholine Mustard Aziridinium Ion (Af64a), Diane Marie Barnes

Master's Theses

No abstract provided.


Genetic Mapping And Characterization Of Acc, The Agrocinopine-Agrocin 84 Region, On Ptic58, The Nopaline-Type Ti Plasmid Of Agrobacterium Tumefaciens Strain C58, G. Thomas Hayman Jan 1989

Genetic Mapping And Characterization Of Acc, The Agrocinopine-Agrocin 84 Region, On Ptic58, The Nopaline-Type Ti Plasmid Of Agrobacterium Tumefaciens Strain C58, G. Thomas Hayman

Dissertations

No abstract provided.


Transcriptional Control Of The Inducible Nitrate Reductase Isoform In Soybean, Glycine Max, John J. Callaci Jan 1989

Transcriptional Control Of The Inducible Nitrate Reductase Isoform In Soybean, Glycine Max, John J. Callaci

Master's Theses

No abstract provided.


The Magnetic Separation Of Rat Anterior Pituitary Cells, Jodi Flaws Jan 1989

The Magnetic Separation Of Rat Anterior Pituitary Cells, Jodi Flaws

Master's Theses

No abstract provided.


Capretto : A New Meat Industry, R J. Suiter Jan 1989

Capretto : A New Meat Industry, R J. Suiter

Journal of the Department of Agriculture, Western Australia, Series 4

Capretto is the term the Italians use for the meat from a goat upto 20 weeks old. For centuries goat meat has featured on tables from the Mediterranean to asia and the Pacific Islands.

Western Australian premium quality capretto has a dressed weight of between 6 and 1kg. Its pinkish flesh is tender and leaner than sheep meat, so it's ideal for the health conscious.

This article describes a market development programme undertaken by the Department of Agriculture's Goat Industry Development Unit (GIDU) and the Australian Cashmere Growers Association's (ACGA) Meat Marketing Committee to establish a premium market for capretto …


Phase-Variation Of Pyelonephritis-Associated Pili In Escherichia Coli: Evidence For Transcriptional Regulation, L. B. Blyn, B. A. Braaten, C. A. White-Ziegler, D. H. Rolfson, D. A. Low Jan 1989

Phase-Variation Of Pyelonephritis-Associated Pili In Escherichia Coli: Evidence For Transcriptional Regulation, L. B. Blyn, B. A. Braaten, C. A. White-Ziegler, D. H. Rolfson, D. A. Low

Biological Sciences: Faculty Publications

The regulation of pyelonephritis-associated pill (pap) pflin gene transcription has been examined using two operons (pap-17 and pap-21) isolated from the pyelonephritogenic Escherichia coli strain C1212. DNA sequence analysis and E.coli minicell analysis were used to map two genes (papB and papl) within the pilin regulatory regions of both pap-17 and pap-21, and the protein products of these genes were identified. Pilin transcription, initiated at the papBA promoter, was monitored by constructing single copy operon fusions with lacZYA in E.coli K-12. Inocula- tion of E.coli (pap'-lac) strains onto solid M9 minimal medium containing glycerol and the Lac indicator X-gal (M9-Glycerol) …


Preliminary Evaluation Of A Dodder Anthracnose Fungus From China As A Mycoherbicide For Dodder Control In The Us, D. K. Cartwright, George E. Templeton Jan 1989

Preliminary Evaluation Of A Dodder Anthracnose Fungus From China As A Mycoherbicide For Dodder Control In The Us, D. K. Cartwright, George E. Templeton

Journal of the Arkansas Academy of Science

Dodder (Cuscuta spp.) is a noxious, parasitic, annual weed throughout most of the United States. A fungus used to control it in China was imported under permit for studies with U.S. dodder species in containment. The fungus, Colletotrichum gloeosporioides, sporulated on liquid and solid media at room temperature. Conidia from 7-12 day old cultures were diluted to 3.5 to 7 X 16⁶ spores ml^-1 for host range inoculations. Germination on water agar at 24 hrs was higher at 28 than 30 or 24 C. Inoculated plants were exposed to dew periods of 12-1 4 hrs at 24 or 28 C, …


In Vitro Culture Of Several Rice Cultivars, A. F. Mirlohi, Lyell F. Thompson, R. H. Dilday, Feng H. Huang, Jameel M. Al-Khayri Jan 1989

In Vitro Culture Of Several Rice Cultivars, A. F. Mirlohi, Lyell F. Thompson, R. H. Dilday, Feng H. Huang, Jameel M. Al-Khayri

Journal of the Arkansas Academy of Science

Tissue culture methods have been established to regenerate certain rice (Oryza sativa L) cultivars, but regeneration of the rice cultivars widely grown in Arkansas has not been reported. This study has established an in vitroculture for the rice cultivars 'Nortai', 'Starbonnet', 'Mars', Tebonnet', 'Newbonnet', and 'Lemont'. Callus was induced in the dark at either 20 or 28 C from dehusked seeds cultured on Murashige and Skoog (MS) medium (Murashige and Skoog, 1962) containing 40 g L^-1 sucrose, 10 g L^1 agar, 0.5, 1.0, or 2.0 mg L^-1 1 2,4-dichlorophenoxyacetic acid (2,4-D) and adjusted to pH 5.7. After four weeks the …


Toward A Resolution Of The Paradox Of Aggressive Displays: Ii. Behavioral Efference And The Communication Of Intentions, Alan B. Bond Jan 1989

Toward A Resolution Of The Paradox Of Aggressive Displays: Ii. Behavioral Efference And The Communication Of Intentions, Alan B. Bond

Papers in Behavior in Biological Sciences

An inference from game-theory models of animal conflict is that adversaries should not inform one another about their level of aggressive motivation. This poses a paradox for the traditional ethological account of graded aggressive displays because it is usually assumed that the adaptive significance of these behavior patterns lies in their making such information available. To resolve the paradox, I propose that communication is only an incidental effect of displays, and that their primary adaptive function is regulation of the intensity of aggressive encounters through positive feedback on aggressive motivation, a process termed "behavioral efference." Evidence in support of this …


Toward A Resolution Of The Paradox Of Aggressive Displays: Ii. Behavioral Efference And The Communication Of Intentions, Alan B. Bond Jan 1989

Toward A Resolution Of The Paradox Of Aggressive Displays: Ii. Behavioral Efference And The Communication Of Intentions, Alan B. Bond

Papers in Behavior in Biological Sciences

An inference from game-theory models of animal conflict is that adversaries should not inform one another about their level of aggressive motivation. This poses a paradox for the traditional ethological account of graded aggressive displays because it is usually assumed that the adaptive significance of these behavior patterns lies in their making such information available. To resolve the paradox, I propose that communication is only an incidental effect of displays, and that their primary adaptive function is regulation of the intensity of aggressive encounters through positive feedback on aggressive motivation, a process termed "behavioral efference." Evidence in support of this …


Biochemical Characterization Of The Axolemmal Mitogen For Cultured Schwann Cells, Mark A. Decoster Jan 1989

Biochemical Characterization Of The Axolemmal Mitogen For Cultured Schwann Cells, Mark A. Decoster

Theses and Dissertations

The molecule(s) involved at the axon plasma membrane (axolemma) which causes Schwann cells to proliferate has been investigated by three biochemical techniques: 1) Alkaline extraction of axolemma resulted in recovery of 95% of the mitogenic activity and 50% of the protein in the membrane-bound portion of the axolemma. 2) The axonal mitogen for Schwann cells may be associated with heparan sulfate proteoglycans at the axonal surface. Treatment of axolemma with heparitinase, which cleaves the glycosidic bonds of sulfated glycosaminoglycans, allowed mitogenic activity to be solubilized. 3) Treatment of axolemma with heparin, a highly sulfated glycosaminoglycan analogous to heparan sulfate, resulted …


Characterization Of Steroid-17,20-Desmolase And 20Α-Hydroxysteroid Dehydrogenase From Clostridium Scindens, Amy Elizabeth Krafft Jan 1989

Characterization Of Steroid-17,20-Desmolase And 20Α-Hydroxysteroid Dehydrogenase From Clostridium Scindens, Amy Elizabeth Krafft

Theses and Dissertations

Clostridium scindens is an obligate anaerobe isolated from the normal intestinal flora of man. It is the only bacterium known at present to synthesize both steroid-17,20-desmolase and 20α-hydroxysteroid dehydrogenase (ZOα-HSDH). This study was undertaken to characterize these neutral steroid transforming reactions in extracts of C. scindens; to purify and characterize the enzymes responsible for side-chain cleavage and 20α- hydroxysteroid oxidoreduction and to clone the genes encoding these enzymes with a view towards studying the mechanism of induction by steroids in a prokaryotic system. Both enzymes were found to be co-inducible in cells cultured in the presence of 17α-hydroxysteroids. In cell …


Propagation Of Blowout Penstemon (Penstemon Haydenii S. Watson): Germination-Enhancing Treatments, Theresa R. Flessner, James L. Stubbendieck Jan 1989

Propagation Of Blowout Penstemon (Penstemon Haydenii S. Watson): Germination-Enhancing Treatments, Theresa R. Flessner, James L. Stubbendieck

Transactions of the Nebraska Academy of Sciences and Affiliated Societies

Development of germination-enhancing treatments will be essential for the recovery of Nebraska's only officially endangered plant species, blowout penstemon (Pensiemon haydenii S, Watson), Effects of cold-moist stratification, mechanical or chemical scarification, and presence or absence of light in combination with alternating temperature regimes on seed germination of blowout penstemon was determined by laboratory studies. Stratified seeds exhibited greater mean germination percentages (21 %) than nonstratified seeds (8%). Effects of mechanical scarification on germination varied with trial. Seeds chemically scarified with concentrated sulfuric acid exhibited greater mean germination percentages (48%) than controls (12%); such scarification may substitute for the effective, …


The Vascular Flora Of Pilot Knob State Preserve, William C. Watson Jan 1989

The Vascular Flora Of Pilot Knob State Preserve, William C. Watson

Journal of the Iowa Academy of Science: JIAS

Pilot Knob State Preserve is a 365 acre (147 ha) area lying within the boundaries of Pilot Knob State Park. Located in north central Iowa near the northeast corner of Hancock County, this preserve resides on the eastern morainal system of the Des Moines Lobe left from the Wisconsinan glaciation. The vegetation of the preserve is primarily a deciduous woodland on rolling hills interspersed with wetland habitats in the hollows. Iowa's only floating bog is present in one of these hollows and supports numerous vascular plants uncommon to the state. Two species, Carex cephalantha (Bailey) Bickn. and Drosera rotundifolia L., …


Characterization Of Aminoisobutyric Acid Transport Systems In Mcf-8, A Line Of Malignant Mouse Mammary Epithelial Cells, Bruce A. Voyles Jan 1989

Characterization Of Aminoisobutyric Acid Transport Systems In Mcf-8, A Line Of Malignant Mouse Mammary Epithelial Cells, Bruce A. Voyles

Journal of the Iowa Academy of Science: JIAS

Uptake of α-aminoisobutyric acid (AIB) by MCF-8, a line of malignant mouse mammary epithelial cells derived from a D2 hyperplastic nodule outgrowth, was found to be mediated by two different transport systems. In actively dividing cells about 60% of total AIB uptake is mediated by an A-like system: transport was Na+ -dependent, was inhibited by N-methyl-AIB, was maximal at pH 7.5 and ceased at pH 6. Transport by this system was reduced by nearly 65% when cell division ceased in confluent cultures, but the addition of insulin and/or calf serum to the medium of quiescent cells restored activity. Transport by …


Loss Of Biological Diversity: A Global Crisis Requiring International Solutions: A Report To The National Science Board, Craig Call Black, Perry L. Adkisson, Gardner Mallard Brown, Rita Rossi Colwell, Charles E. Hess, James B. Holderman, K. June Lindstedt-Siva, William A. Nierenberg, Peter Hamilton Raven, Theodore M. Smith, Edward O. Wilson, W. Franklin Harris Jan 1989

Loss Of Biological Diversity: A Global Crisis Requiring International Solutions: A Report To The National Science Board, Craig Call Black, Perry L. Adkisson, Gardner Mallard Brown, Rita Rossi Colwell, Charles E. Hess, James B. Holderman, K. June Lindstedt-Siva, William A. Nierenberg, Peter Hamilton Raven, Theodore M. Smith, Edward O. Wilson, W. Franklin Harris

Harold W. Manter Laboratory of Parasitology: Library Materials

Executive Summary

Biological diversity refers to the variety and variability among living organisms and the ecological complexes in which they occur. Diversity can be defined as the number of different items and their relative frequency. For biological diversity, these items are organized at many levels, ranging from complete ecosystems to the chemical structures that are the molecular basis of heredity. Thus, the term encompasses different ecosystems, species, genes, and their relative abundance (OTA, 1987).

There is an ongoing, unprecedented loss of the variety as well as absolute numbers of organisms-from the smallest microorganism to the largest and most spectacular of …


Fine Structure And Organ Culture Of Chick Embryo Dorsal Aorta, C. Ward Kischer, Michael Jaqua Dec 1988

Fine Structure And Organ Culture Of Chick Embryo Dorsal Aorta, C. Ward Kischer, Michael Jaqua

Scanning Microscopy

Embryonic blood vessels have not been grown in organ culture, in a way which might easily submit them to studies of vascular organogenesis. The chick embryo dorsal aorta is easily accessible and relatively simple to explant to culture. Its organ culture may provide a model for wounding and repair of the intima and/or media and provide a model for studies of growth (or maintenance) and differentiation. Fresh dorsal aorta and its organ culture from the chick embryo was characterized morphologically by light microscopy scanning (SEM) and transmission electron microscopy (TEM) from days 4 to 18. Explants were incubated up to …


The Short Term Effects Of Manganese Toxicity On Isocitrate Dehydrogenase In Wheat & Tobacco, Juergen Pfeiffer Dec 1988

The Short Term Effects Of Manganese Toxicity On Isocitrate Dehydrogenase In Wheat & Tobacco, Juergen Pfeiffer

Masters Theses & Specialist Projects

The short term effects of high manganese levels (80 mg/L) on wheat and tobacco isocitrate dehydrogenase (IDH) activity were compared. The change in activity was then compared to the concentrations of manganese in the tissues.

As the time of manganese exposure increased, the fresh weight IDH activities in wheat and tobacco decreased. In contrast both control groups had similar enzyme activities every 6 hr over the 24 hr test period. The decrease in IDH activity of wheat and tobacco plants in experimental groups seemed to be related to an increase of the manganese in the leaf tissue. The slower decrease …


The Analysis Of Wiremark, Karen L. Birks Dec 1988

The Analysis Of Wiremark, Karen L. Birks

Paper Engineering Senior Theses

Wire Mark is the impression left on the paper web by its initial forming fabric. Wire Mark can be explained as differing levels of density in a sheet. By definition, the ideal formation is a sheet which has completely uniform density. Many changes have occurred in forming fabrics over the years to resolve this problem. The development of double and triple layer wires for a smoother surface have come about. This thesis takes these forming wires and further modifies the surfaces to reduce wire mark patterns. The action is analyzed by several common paper tests, along with the aid of …


The Radiomycetaceae (Mucorales; Zygomycetes). Calcium Oxalate Crystals On The Sporangiolar Wall And Aerial Hyphae, G. L. Benny, S. R. Khan Nov 1988

The Radiomycetaceae (Mucorales; Zygomycetes). Calcium Oxalate Crystals On The Sporangiolar Wall And Aerial Hyphae, G. L. Benny, S. R. Khan

Scanning Microscopy

Calcium oxalate crystals occur on the sporangiolar appendages and aerial hyphae of the two known genera (Hesseltinella, Radiomyces) of the mucoralean family Radiomycetaceae. In Hesseltinella the sporangiolar appendages are acicular with a polygonal, square, or hexagonal, discoid base. The appendage core consists of calcium oxalate and is composed of two portions: (1) a round, acicular spine with a more or less hexagonal base, and (2) a square, polygonal, or hexagonal, discoid base with a central perforation that generally contains the spine base. Both portions of the spine core appear to be readily separable. In species of Radiomyces the …


Dynamic Analyses Of Lymphoblast Membranes Exposed To Alpha Interferon Using Flow Cytometry And Fluorescence Recovery After Photobleaching, E. Balint, A. Aszalos, P. S. Pine, P. M. Grimley Oct 1988

Dynamic Analyses Of Lymphoblast Membranes Exposed To Alpha Interferon Using Flow Cytometry And Fluorescence Recovery After Photobleaching, E. Balint, A. Aszalos, P. S. Pine, P. M. Grimley

Scanning Microscopy

Interferons represent a major group of the biologic response modifiers which exert multipotent effects upon cell growth, cytodifferentiation and immune functions. Previous experimental studies with alpha interferon (IFN-𝝰) have suggested that modulation of transmembrane signaling could be a critical determinant in the bioregulatory diversity. To determine whether any initial changes at the plasma membrane would directly correlate with one or more actions of IFN-𝝰, we investigated cultures of Daudi lymphoblasts which are uniquely susceptible to growth inhibition. Complementary biophysical techniques were applied. In one approach, changes in plasma membrane ion flux were measured by flow cytometry, using a fluorescent dye …


Fast Track Physics: [Dr. Konstantin Goulianos], M. S. Kaplan Oct 1988

Fast Track Physics: [Dr. Konstantin Goulianos], M. S. Kaplan

Rockefeller University Research Profiles

Rockefeller University Research Profiles are a series of scientific profiles that were published quarterly, from 1980-1990, by the Rockefeller University. Each issue features the research and achievements of an individual Rockefeller University scientist.


The Synthesis And Evaluation Of 5-Phenyloxazolidines As Potential Cardiovascular Drugs, Tammy C. Wang Oct 1988

The Synthesis And Evaluation Of 5-Phenyloxazolidines As Potential Cardiovascular Drugs, Tammy C. Wang

Chemistry & Biochemistry Theses & Dissertations

Drugs such as adrenoceptor antagonists and certain centrally acting agents are known to lower blood pressure and thus serve as clinically useful antihypertensive agents. Norepinephrine 4, a natural ∝-adrenoceptor agonist, is the major agent associated with increased blood pressure in the periphery. Based on a careful structure-activity comparison, a series of substituted oxazolidines, 20, 21, 22 and 23, have been designed as possible antihypertensive candidates. Specifically, 22 and 23 have been synthesized to serve as potential norepinephrine antagonists.

Preliminary evaluation of these compounds indicated that they were not antihypertensive in nature. The more active compound, 23, …


A Study Of Human Exposure To Benzo(A)Pyrene (Bap) Through Different Pathways. Part A ; Assessment Of Benzo(A)Pyrene (Bap) Exposure Through Urine Analysis With The Hydriodic Acid Reduction Reaction. Part B, Shao-Keng Liang Sep 1988

A Study Of Human Exposure To Benzo(A)Pyrene (Bap) Through Different Pathways. Part A ; Assessment Of Benzo(A)Pyrene (Bap) Exposure Through Urine Analysis With The Hydriodic Acid Reduction Reaction. Part B, Shao-Keng Liang

Theses

PART A: An investigation of total human exposure to an environmental pollutant is described. The study is being conducted in a community impacted by a foundry suspected to be a dominant local source of benzo(a)pyrene (BaP). The research aims to assess the relative contributions of indoor and outdoor sources and to measure BaP in media including indoor air, outdoor air, food and water.

PART B: A method for biological monitoring of exposure to benzo(a)pyrene, a representative polycyclic aromatic hydrocarbon (PAH), has been developed. The analytical procedure includes extraction of PAH and PAH metabolites from urine using commercial cartridges containing c …


A Comparison Of The Elemental Concentrations In Tissue Thymocytes From Diabetic And Non-Diabetic Rats, A. Warley Sep 1988

A Comparison Of The Elemental Concentrations In Tissue Thymocytes From Diabetic And Non-Diabetic Rats, A. Warley

Scanning Microscopy

The elemental concentrations in thymocytes from control and diabetic rats were studied by use of the techniques of cryofixation and X-ray microanalysis to determine whether any changes occur in the diseased state. Decreases in the concentrations of the elements P and K were found in thymocytes from the subcapsular and cortical regions of the gland in thymus tissue taken 4 days after the onset of diabetes. A decrease in the concentration of Mg was also found in thymocytes from the subcapsular region of the gland. These changes suggest that the metabolism of thymocytes in vivo is altered in the diabetic …


Preparation Of Isolated Blood Capillaries, R. C. Wagner, R. A. Buchanan, Ritchie Froehlich Sep 1988

Preparation Of Isolated Blood Capillaries, R. C. Wagner, R. A. Buchanan, Ritchie Froehlich

Scanning Microscopy

Blood capillaries have been isolated from various tissue sources yielding suspensions of capillary segments. These have provided opportunities to study the cellular properties of capillary endothelium under conditions uncomplicated by the presence of stromal tissues and in which measured parameters can be attributed to endothelial cells. Fresh capillary isolates have been used directly as experimental systems but the yield of endothelium is quite low. Amplification of endothelial biomass has been accomplished by using freshly isolated capillaries as explants for primary tissue culture. It has not been previously possible, however, to obtain large amounts of capillary endothelium from a single preparation …


Spinal Osteoporosis, Charles H. Chesnut Iii Sep 1988

Spinal Osteoporosis, Charles H. Chesnut Iii

Henry Ford Hospital Medical Journal

No abstract provided.


Metabolic Bone Disease In Children, Michael P. Whyte Sep 1988

Metabolic Bone Disease In Children, Michael P. Whyte

Henry Ford Hospital Medical Journal

No abstract provided.


The Inhibition Of Bone Formation Occurring Under Weightlessness : The Effect Of Skeletal Unloading On Serum Levels Of A Bone-Derived Growth Factor, Jean D. Sibonga Sep 1988

The Inhibition Of Bone Formation Occurring Under Weightlessness : The Effect Of Skeletal Unloading On Serum Levels Of A Bone-Derived Growth Factor, Jean D. Sibonga

Loma Linda University Electronic Theses, Dissertations & Projects

A deleterious effect of spaceflight on human health is the loss of bone associated with the prolonged lack of gravitational stress on the skeleton. A potential for bone loss is indicated by the hypercalciuria and decreased heel bone density determined in Skylab astronauts. Histological studies of juvenile laboratory rats in actual spaceflight and in simulation models document a suppression of bone formation with little alteration of bone resorption. The mechanism for net bone loss needs to be defined in order to develop measures for its prevention or correction.

Skeletal growth factors, which may mediate coupling and locally regulate bone volume …


An Analysis Of Protein-Ligand Interactions For Enzyme Ii-Mannitol From Escherichia Coli, Brent Lee Wood Sep 1988

An Analysis Of Protein-Ligand Interactions For Enzyme Ii-Mannitol From Escherichia Coli, Brent Lee Wood

Loma Linda University Electronic Theses, Dissertations & Projects

Enzyme IImtl of Escherichia coli was purified from mtlA-overexpressing E. coli strain LJ1112 extraction of isolated membranes with deoxycholate, followed by hexyl agarose and ω-amino hexyl agarose chromatography in Lubrol PX. A 10-fold increase in total pure protein and 2.5-fold increase in specific activity over previously reported procedures was obtained. Tryptic fragments of Enzyme IImtl were also purified and identified as the membrane and cytoplasmic domains by protein sequencing and SDS-PAGE. The fluorescence spectrum of Enzyme IImtl suggested that two populations of tryptophan residues existed with emission maxima at 322 and 344 nm, corresponding to buried …