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Articles 541 - 570 of 686

Full-Text Articles in Biology

Evaluation Of A Rapid-Screening Toxicity Test Using The Ciliate, Colpoda Inflata (Stokes): Sensitivity And Bioavailability To Model Compounds, Daria Galina Mochan Aug 1996

Evaluation Of A Rapid-Screening Toxicity Test Using The Ciliate, Colpoda Inflata (Stokes): Sensitivity And Bioavailability To Model Compounds, Daria Galina Mochan

Dissertations and Theses

Standard toxicity tests often require high costs for maintaining healthy cultures, so few test species are employed in routine ecotoxicological analysis. An alternative is the "battery of tests" approach involving using rapid toxicity tests for screening. Rapid-screening toxicity tests must display organism sensitivity, similarity in responses to other test organisms, relevancy to many circumstances, and repeatability. Protozoa are ideal candidates for rapid-screening bioassays. They are cosmopolitan, play important roles in ecosystems, and have high reproductive rates. Many protozoa can form a resting stage (cyst) that remains viable during adverse conditions, eliminating the need for maintaining continuous cultures for testing.

The …


Thermal Preference Of Spring And Fall Chinook Salmon (Oncorhynchus Tshawytscha) During Smoltification, Sally T. Sauter Aug 1996

Thermal Preference Of Spring And Fall Chinook Salmon (Oncorhynchus Tshawytscha) During Smoltification, Sally T. Sauter

Dissertations and Theses

Innate species-specific temperature preferences of fish are subjected to fluctuations under a variety of environmental, physiological, and developmental conditions. The temperature preference patterns of two ecologically distinct races of chinook salmon (Oncorhynchus tshawytscha) were investigated as laboratory held animals underwent smoltification. Smoltification is a distinct developmental stage in the life history of anadromous salmonids when juvenile fish undergo profound behavioral, morphological, and physiological differentiation prepatory to seawater entry. A group of spring and fall chinook salmon were held under identical conditions of increasing water temperature over the course of smoltification. Another group of spring and fall chinook salmon were held …


Mutation Analysis Of Fibrillin-2 (Fbn2) And Microfibril Associated Protein-3 (Mfap-3): Two Genes Associated With Congenital Contractural Arachnodactyly (Cca), Also Known As Beal's Syndrome, Darcie Babcock May 1996

Mutation Analysis Of Fibrillin-2 (Fbn2) And Microfibril Associated Protein-3 (Mfap-3): Two Genes Associated With Congenital Contractural Arachnodactyly (Cca), Also Known As Beal's Syndrome, Darcie Babcock

Dissertations and Theses

Congenital Contractural Arachnodactyly (CCA), also known as Beal's syndrome, is an autosomal dominant disorder characterized by multiple congenital joint contractures, arachnodactyly, dolichostenomelia, and scoliosis with only rare ocular or cardiovascular involvement. CCA has been linked to the fibrillin-2 (FBN2) gene located on chromosome 5q23-31. The phenotype ofCCA is similar to Marfan syndrome (MFS) which is caused by defects in the fibrillin-1 (FBNl) gene located on chromosome 15. Fibrillin-1 and fibrillin-2 are components of extracellular matrix (ECM) elastic microfibrils. The linkage studies performed on families affected with CCA suggest that another gene in the area ofFBN2 could also be responsible for …


Captive Environmental Influences On Behavior In Zoo Drills And Mandrills (Mandrillus), A Threatened Genus Of Primate, Erik Terdal Jan 1996

Captive Environmental Influences On Behavior In Zoo Drills And Mandrills (Mandrillus), A Threatened Genus Of Primate, Erik Terdal

Dissertations and Theses

Drills (Mandrillus leucophaeus) are an endangered species of African monkey (Cercopithecidae), and their sole congener the mandrill (Mandrillus sphinx) is vulnerable to extinction. Both species are threatened in the wild by deforestation and hunting.

Drills have a poor record of captive reproduction. Many individuals appear to have behavioral deficiencies which interfere with reproduction. Thus, the zoo population of drills does not serve as a “hedge” against the species’ total extinction: drills are endangered in captivity as well as in the wild. Mandrills, by contrast, reproduce well in captivity. Information on the behavior of mandrills in captivity may help zoo managers …


Streamnet: An Integrated Information System Serving Fisheries Scientists And Managers In The Columbia River Basin - Or - Is Innovation Possible When Differing Traditions Collide?, Gretta E. Siegel Jan 1996

Streamnet: An Integrated Information System Serving Fisheries Scientists And Managers In The Columbia River Basin - Or - Is Innovation Possible When Differing Traditions Collide?, Gretta E. Siegel

Library Faculty and Staff Publications and Presentations

StreamNet is a project which brings together fisheries information collected by state agencies, federal agencies, and Indian tribes in a system of interconnected sets of data about anadromous fish in the Columbia River Basin. The data are used to observe trends in stock abundance escapement, hatchery production, etc. Each data point is linked to corresponding literature which can be searched separately in a references database. Plans are in progress to make this system available via the Internet. Data entry for the reference module is done via Microsoft Access. The application has been designed to include features of both a catalog …


Dna Sequences Involved In The Regulation Of Human C-Myc Gene Expression By Herpes Simplex Virus Type 1 (Hsv-1), Shanli Ye Nov 1995

Dna Sequences Involved In The Regulation Of Human C-Myc Gene Expression By Herpes Simplex Virus Type 1 (Hsv-1), Shanli Ye

Dissertations and Theses

The human c-myc gene is a cellular proto-oncogene composed of three exons and two introns. Transcription of c-myc is controlled by two promoters, P1 and P2. The activity of these promoters is regulated by many factors, such as cellular transcription factors E2F, YY1, and HSV-1 immediate-early proteins, ICP0, ICP4.

Many regulatory elements located both upstream of and between P1 and P2 have been identified, and some of these are required for optimum expression of c-myc. In this thesis research, a region downstream from P2 in the c-myc exon 1 was identified by its response to transactivation …


Shoot Structure Of Boschniakia Hookeri Walpers (Orobanchaceae), John Leland Babur Aug 1995

Shoot Structure Of Boschniakia Hookeri Walpers (Orobanchaceae), John Leland Babur

Dissertations and Theses

Boschniakia hookeri Walpers has been found to parasitize the roots of Gaultheria shallon Pursh, Arctostaphylos uva-ursi (l.) Spreng, and Vaccinium ovatum Pursh, all members of the Ericaceae. This is the first documented report of the parasitism of Vaccinium ovatum. The subterranean shoot of B. hookeri originates endogenously from the perennial tubercle of the parasite. The shoot has an eustele, composed of collateral vascular bundles, arranged in four composite fronts and separated by four wide 'leaf gaps.' Pits on metaHylem vessels range from nearly circular to laterally elongated. Rll vessel members have simple perforations. Ouerall, the Hylem of subterranean shoots contained …


The Role Of Pulmocutaneous Baroreceptors In The Control Of Lymphatic Heart Rate In The Toad Bufo Marinus, Dane Alan Crossley Ii Jul 1995

The Role Of Pulmocutaneous Baroreceptors In The Control Of Lymphatic Heart Rate In The Toad Bufo Marinus, Dane Alan Crossley Ii

Dissertations and Theses

The present study documents that baroreceptors located in the pulmocutaneous artery (PCA) are key components in control of lymph heart rate in amphibians. A negative feedback control loop exists between arterial pressure and lymphatic heart rate. The recurrent laryngeal nerve (rLN), which innervates the PCA baroreceptors, transmits information on arterial pressure to integration centers in the central nervous system. Lymphatic heart rate (LHR) is reduced as a result of increases in arterial pressure. This loop was determined using three experimental protocols. First, the correlation between LHR reduction and hormonally induced vasoconstriction was determined. Increases in arterial pressure due to pressor …


Renal Responses To Differential Rates Of Blood Volume Expansion In The Toad, Bufo Marinus, Mark Edward Bolke Jul 1995

Renal Responses To Differential Rates Of Blood Volume Expansion In The Toad, Bufo Marinus, Mark Edward Bolke

Dissertations and Theses

Three aspects of renal function were measured in the toad, Bufo marinus (N=lO): (1) effect of rate of blood volume expansion on renal functions (UFR; GFR; urine and plasma ion concentrations; and ion excretion rates), (2) effect of hypo- and hyperosmotic blood volume expansions on renal functions, and (3) role of GFR and tubular processes in the differential response of UFR under different osmotic expansion stresses. Renal responses to differential rates of blood volume expansion have not been investigated in amphibians. Rate responses will be analyzed considering effects: ( 1) during infusion (neural, or, short term regulation of extracellular fluid …


Variation In Plasma Prostaglandin E2 Level In Mouse During Infection With Trichinella Spiralis And Trichinella Pseudospiralis, Zahra Mehdizadehkashi Jul 1995

Variation In Plasma Prostaglandin E2 Level In Mouse During Infection With Trichinella Spiralis And Trichinella Pseudospiralis, Zahra Mehdizadehkashi

Dissertations and Theses

Polymorphonuclear leukocytes infiltrate tissues in response to an inflammatory stimulus such as endotoxin or parasite products. Previous studies have shown an extensive cellular infilteration about the parasitized skeletal muscle of mouse infected with the nematode, Trichinella spiralis. Infection of the host with Trichinella pseudospiralis, on the other hand, is associated with a dramatic suppression of inflammatory cellular response. Prostaglandin Bi is a product of arachidonic acid metabolism and is synthesized by variety of cell types. Prostaglandins of the E series have been generally known to suppress inflammatory responses. In the present study, I have investigated the possible relation between plasma …


The Chemotactic Response Of Neutrophils To Components Of The Sera Of Mice Infected With Trichinella Spiralis, Sara Lynn Youngman Jul 1995

The Chemotactic Response Of Neutrophils To Components Of The Sera Of Mice Infected With Trichinella Spiralis, Sara Lynn Youngman

Dissertations and Theses

Neutrophils accumulate around Trichinella spiralis larvae encysted in skeletal muscle cells of the host. The magnitude of the neutrophil infiltration follows a pattern relating to the stage of infection of T.spiralis. This study was performed to determine if there are factors chemotactic for neutrophils present in the sera of mice infected with T.spiralis, and if present, to compare the chemotactic potential of sera from several time points during the infection. Female MRL++ mice hosted the T.spiralis infection and provided neutrophils for all experiments. The chemotactic potentials of sera were tested by placing 150 ul of serum collected …


Effect Of Ototoxic Drugs On The Amphibian Auditory System: Injection Of Gentamicin Sulfate Into Anuran Otic Capsules And Recovery Of Thresholds, Michael Patrick Brown May 1995

Effect Of Ototoxic Drugs On The Amphibian Auditory System: Injection Of Gentamicin Sulfate Into Anuran Otic Capsules And Recovery Of Thresholds, Michael Patrick Brown

Dissertations and Theses

Hair cell trauma from aminoglycosides, which may lead to permanent loss of hair cells in mammals, was studied physiologically in frogs by measuring an auditory evoked potential (AEP) in Rana pipiens. The AEP was evaluated in order to measure threshold shift (TS) and recovery from TS after the administration of the aminoglycoside antibiotic, gentamicin. To obtain an AEP, chronic electrodes were implanted into the cranium near the cochlear nucleus. The frogs were then exposed to frequency-specific narrow band "clicks" which included a single period 1 kHz sinewave, and a computer synthesized high frequency and low frequency click. Amphibians have two …


Phytoplankton In Mt. St. Helens Lakes, Washington, Cynthia Fay Baker Apr 1995

Phytoplankton In Mt. St. Helens Lakes, Washington, Cynthia Fay Baker

Dissertations and Theses

Phytoplankton communities in fifteen lakes in the Mt. St. Helens area were surveyed to assess the abundance and species present. Eleven of the lakes were inside the blast zone of the 1980 eruption and four were located outside the blast zone as a comparison. The hypothesis is that lakes will cluster together based on the algal species present and that some algae will be correlated with certain environmental conditions. A cluster analysis was performed to determine if the lakes would group together based on algal abundance. There did not appear to be any distinct clustering among the study lakes, but …


Zooplankton Community Structure In Lakes Near Mt. St. Helens, Wa, Larry Duane Scharnberg Feb 1995

Zooplankton Community Structure In Lakes Near Mt. St. Helens, Wa, Larry Duane Scharnberg

Dissertations and Theses

Eighteen lakes around Mt. St. Helens (MSH) were sampled for zooplankton from September '92 until September '94. Samples were enumerated and identified to the species level in most cases. Standard deviation and t-tests were performed to determine the precision of enumeration methods and replication of duplicate tows. Palatability indexes based upon predator preferences were developed and coupled with length-frequency analyses as indicators of predation pressure. The weighted means of the summer samples were then subjected to cluster analysis in an attempt to categorize lakes with respect to zooplankton community structure. Lastly, the community compositions and abundances of MSH lakes were …


The Biogeochemistry Of Lakes In The Mount St. Helens Blast Zone, Victor Lee Menting Feb 1995

The Biogeochemistry Of Lakes In The Mount St. Helens Blast Zone, Victor Lee Menting

Dissertations and Theses

Dilution and ash weathering are the most important processes controlling the ion chemistry of lakes in the Mount St. Helens blast zone. Gibbs' models indicated total dissolved solids were decreasing as a result of dilution from high precipitation and runoff and the lakes plot in the rock weathering dominated region. Plots of theoretical dilution curves indicated a decline in ion concentrations as a result of dilution. Ion concentrations followed the exponential decline predicted by the dilution curve, although concentrations were higher than predicted by the curve. Increased concentrations were a result of the rapid weathering of ash in basins and …


Investigations On Glycolipid Production By Pseudomonas Putida Grown On Toluene In Batch And Continuous Culture Conditions, Keith Foorest Dockery Nov 1994

Investigations On Glycolipid Production By Pseudomonas Putida Grown On Toluene In Batch And Continuous Culture Conditions, Keith Foorest Dockery

Dissertations and Theses

Utilization of toluene by Pseudomonas putida as its sole carbon and energy source affects morphology, outer membrane protein composition, and glycolipid production. Two strains of P. putida were found to utilize toluene and to coexist in continuous and batch culture. The two strains were designated translucent and opaque, based upon their readily identifiable coloration when grown on Luria agar. The translucent strain was the dominant strain in continuous culture conditions. The outer membrane proteins of P. putida were separated by sodium dodecyl sulphate polyacrylamide gel electrophoresis. When toluene is the carbon and energy source, the trend in protein composition was …


Changes In Proteins Associated With Nitrogen Fixation And Iron Nutrition In The Marine Cyanobacterium Trichodesmium, Karen Marie Elardo Nov 1994

Changes In Proteins Associated With Nitrogen Fixation And Iron Nutrition In The Marine Cyanobacterium Trichodesmium, Karen Marie Elardo

Dissertations and Theses

This investigation tested the hypothesis that iron, as a micronutrient, will affect proteins in Trichodesmium and therefore affect nitrogen fixation. Changes in proteins that are a result of iron enrichment were compared to naturally occurring diel changes. Alterations in the iron protein of nitrogenase were compared to nitrogen fixation rates using the acetylene reduction technique. The observed changes in proteins were compared in Trichodesmium colonies from the Caribbean Sea and the Sargasso Sea.

Trichodesmium colonies were monitored for protein and iron content over a diel period on two cruises. The changes in protein and iron content in Trichodesmium colonies were …


A Comparison Of Neutrophil Migration In The Mouse In Response To Infection With Three Species Of Trichinella, Jon Darin Prulhiere Nov 1994

A Comparison Of Neutrophil Migration In The Mouse In Response To Infection With Three Species Of Trichinella, Jon Darin Prulhiere

Dissertations and Theses

The Genus Trichinella is currently thought to consist of 8 separate species. Several methods have been used to help differentiate these. In this study the ability of three of these species, T. spiralis, T. pseudospiralis, and T. sp. 3 to independently infect MRL++ mice was compared at 5, 7, 11, 18 and 20 days post infection (dpi) with the hope of discovering new distinguishing characteristics. Of interest was the development of inflammation through the accumulation of neutrophils associated with larvae of Trichinella in mouse skeletal muscle. This was evaluated with routine histological stains, endogenous peroxidase staining and immunohistochemical …


The Dna Sequence Required For The Maximal Transactivation Of The Vp5 Gene Of Herpes Simplex Virus Type 1, Shin Chen Jul 1994

The Dna Sequence Required For The Maximal Transactivation Of The Vp5 Gene Of Herpes Simplex Virus Type 1, Shin Chen

Dissertations and Theses

A regulatory element involved in the transcriptional activation of the major capsid protein (VP5) of herpes simplex virus type 1 was identified and characterized in this research project. Gel mobility shift assay with nuclear extracts from both uninfected and HSV-1 infected HeLa cells identified two major protein-DNA complexes involving the VP5 promoter. No viral specific complex found. DNase I and orthophenanthroline-Cu+ footprint analyses in the same laboratory revealed that the two complexes involve a single binding site, GGCCATCTTGAA, located between -64 and -75 bp relative to the VP5 cap site. To determine the function of this leaky-late binding site …


Breeding Patterns Of Eastern Phoebes In Kansas: Adaptive Strategies Or Physiological Constraint?, Michael T. Murphy Jul 1994

Breeding Patterns Of Eastern Phoebes In Kansas: Adaptive Strategies Or Physiological Constraint?, Michael T. Murphy

Biology Faculty Publications and Presentations

Data were collected on annual (1980-1983) and seasonal (spring vs. summer) variation in reproduction by the double-brooded Eastern Phoebe (Sayornis phoebe) to test the proposal that phoebes modify reproductive patterns on a seasonal basis and switch from being brood survivalists in spring to brood reductionists in summer. Clutch size did not differ between spring and summer broods nor among years, but spring nests fledged one more nestling than summer nests. In 1981 breeding began earlier, eggs were larger, and nestlings grew faster than in all other years. Clutch size and egg mass within spring clutches increased seasonally. Egg mass was …


Chlorophyll Characterization Of Three Mistletoes And The Chloroplast Ultrastructure Within Aerial And Endophytic Tissues Of Phoradendron Juniperinum, Wesley Emanuel Dubbs Jun 1994

Chlorophyll Characterization Of Three Mistletoes And The Chloroplast Ultrastructure Within Aerial And Endophytic Tissues Of Phoradendron Juniperinum, Wesley Emanuel Dubbs

Dissertations and Theses

The aerial shoot pigments of three epiphytic mistletoes and their hosts were examined and the results were found to concur with earlier reports. Emphasis was placed on the mistletoe Phoradendron juniperinum. Absorbance spectroscopy indicated a very similar ratio of pigments in both the aerial tissue of the mistletoe and its juniper host. Spectroscopic examination found the presence of chlorophyll in the endophytic tissue of the genus Phoradendron for the first time. Total chlorophyll concentrations of the endophytic tissue of Phoradendron juniperinum were found to be approximately 10% that of aerial shoots. However, chlorophyll a/b ratios of endophytic tissue were …


Investigations Of Factors Affecting The Transcriptional Regulation Of Herpes Simplex Virus Type 1 Βγ (Leaky-Late) Genes, Rosemary Ann Lown May 1994

Investigations Of Factors Affecting The Transcriptional Regulation Of Herpes Simplex Virus Type 1 Βγ (Leaky-Late) Genes, Rosemary Ann Lown

Dissertations and Theses

Herpes simplex virus type 1 (HSV-1) is a virus commonly causing cold sores in humans, however, virulent infections are known to produce debilitating encephalitis and death.

HSV-1 transcription is carried out by the host cell RNA polymerase II in a tightly regulated temporal cascade. The first genes transcribed, the a genes, are activated in the absence of viral DNA synthesis. Transcription of the other temporal classes, the β, βγ, and γ genes is dependent upon the protein products of the a genes for activation.

The purpose of this study was to investigate the factors that contribute to this rigid regulation …


A Study Of Understory Plant Recovery After A Forest Fire In The Columbia River Gorge, Mark Alan Pittsenbarger May 1994

A Study Of Understory Plant Recovery After A Forest Fire In The Columbia River Gorge, Mark Alan Pittsenbarger

Dissertations and Theses

Between October 9, 1991 and October 16, 1991 a fire burned 577 hectares in the Columbia River Gorge near the west end on the Oregon side. All of the area burned consisted of second growth Pseudotsuga menziesii and the accompanying understory. This was the first disturbance of this magnitude in this part of the Columbia River Gorge since 1902. The purpose of this study was to examine the pattern of understory recovery in the first two years following the fire. This study also sought to learn: 1) how Pseudotsuga menziesii seedlings are recruited into the population, 2) how quickly the …


Extracellular Matrix Proteins Of The Nurse Cell Capsule In Trichinella Spiralis Infections, Mary Louise Taylor Apr 1994

Extracellular Matrix Proteins Of The Nurse Cell Capsule In Trichinella Spiralis Infections, Mary Louise Taylor

Dissertations and Theses

The infectious first-stage larvae of the nematode Trichinella spiralis is an intracellular parasite of altered skeletal muscle. Invasion of the muscle cell initiates a series of morphological changes in the host muscle cell which ultimately results in a specialized unit called the nurse cell. The completed nurse cell consists of a collagenous capsule, matrix of altered sarcoplasm, and a circulatory rete.

The purpose of this study was to determine the types of collagen present in the nurse cell capsule. Additionally, the presence of the glycoproteins, laminin and tenascin was determined. This study also sought to demonstrate the location of the …


Relationships Between Avian Diversity And Vegetational Parameters In Forested Patches Of The Tualatin Mountains, Oregon, Jerry Sexton Fugate Apr 1994

Relationships Between Avian Diversity And Vegetational Parameters In Forested Patches Of The Tualatin Mountains, Oregon, Jerry Sexton Fugate

Dissertations and Theses

The effect of contiguous forested habitat area on local avian diversity and species richness in the Tualatin Mountain area of northwestern Oregon was investigated. Observations of eight forested stands representing seven area values (1, 2, 7, 14, 18, 24 and 40 hectares) were made during the spring and summer of 1991 and 1992. The variables measured were chosen in an attempt to show possible relationships between vegetation factors, spatial patterns and bird communities. Kendall's rank correlation coefficients were used to analyze the data. Avian species richness and diversity were significantly correlated with forest stand (patch) size. The only significant correlation …


Evidence For The Eutrophication Of Selected Coastal Dunal Lakes: Historical Comparison Of Indices For Nutrient Enrichment, Steven Gregory Dagget Apr 1994

Evidence For The Eutrophication Of Selected Coastal Dunal Lakes: Historical Comparison Of Indices For Nutrient Enrichment, Steven Gregory Dagget

Dissertations and Theses

Three coastal Oregon dunal lakes, Mercer Lake, Munsel Lake, and Woahink Lake, were studied in an effort to determine if eutrophication has occurred since initial studies were conducted in 1938 and to determine each lake's current trophic status. Data collected in 1991 and 1992 for phytoplankton primary productivity; chlorophyll a; phytoplankton species, biovolumes, and densities; nutrients; optical characteristics; and dissolved oxygen were compared with historical data sets. Additional data for zooplankton, benthic invertebrates, and other relevant limnological data were used to more completely characterize each lake.

Phytoplankton primary productivity measurements indicate that biological productivity has increased at each lake …


Studies On The Role Of Cellular Factor, Yy1, In Herpes Simplex Virus Type 1 Late Gene Expression, Xuehui Liu Apr 1994

Studies On The Role Of Cellular Factor, Yy1, In Herpes Simplex Virus Type 1 Late Gene Expression, Xuehui Liu

Dissertations and Theses

The herpes simplex virus 1 (HSVl) VP5 gene codes for the major viral capsid protein. Understanding of the mechanism of how the VP5 gene is regulated in host cells will help us to understand the molecular action of the HSV 1 life cycle and its interplay with the host cell gene expression machinery (transcription and translation). This may ultimately provide scientific bases for both better prevention and cure of HSV 1 caused diseases. Previous work from Dr. Robert L. Millette' s laboratory has indicated that a 164 base pair region of the VP5 promoter gene could activate the transcription of …


Recovery Of Marsh Vegetation At Malheur Lake Following An Extended Flood, Sherry Vlasta Spencer Feb 1994

Recovery Of Marsh Vegetation At Malheur Lake Following An Extended Flood, Sherry Vlasta Spencer

Dissertations and Theses

Water levels of Malheur Lake in southeastern Oregon fluctuate widely with seasonal and cyclic climatic changes. Seven years of severe flooding from 1978 to 1984 produced the highest water levels in recorded history and covered almost all marsh vegetation. Seven years of drought followed the flooding, and by 1992 the water level had dropped to the lowest point in nearly 60 years. A survey of vegetation colonizing the lakeshore as flood water receded was conducted from 1989 to 1992 to describe the reestablishment of marsh vegetation. Six transects were placed in three different ecological units of the lake. Frequency and …


The Influence Of Trichinella Spiralis Infection On Heat Shock Protein 72 Production In Mrl++ Mouse Intestinal Cells, Lisa Ann Kilejian Jul 1993

The Influence Of Trichinella Spiralis Infection On Heat Shock Protein 72 Production In Mrl++ Mouse Intestinal Cells, Lisa Ann Kilejian

Dissertations and Theses

The production of Heat Shock Protein 72, the inducible form of the highly conserved 70 kilodalton heat shock protein family, was investigated in MRL++ mouse intestine during the two weeks of a Trichinella spiralis infection. Within hours of an oral infection using the encysted Trichinella spiralis found in the diaphragm of an infected mouse, the larvae are released from the cyst in the stomach. They travel to the intestine and burrow into the epithelial layer of the intestine. The jejunum is the primary site of the intestinal phase of trichinosis. This stage of infection in the jejunum was the focus …


Cytogenetics Of Delphinium (Ranunculaceae) Species Native To Oregon, Jill Yeatman Turner Nov 1992

Cytogenetics Of Delphinium (Ranunculaceae) Species Native To Oregon, Jill Yeatman Turner

Dissertations and Theses

Evidence of hybridization, known to occur in the genus Delphinium (Ranunculaceae ), has recently been discovered among certain Delphinium species native to Oregon. This issue was investigated by cytogenetic analysis of four native species of Oregon, D. trolliifolium, D. menziesii, D. pavonaceum and D. leucophaeum, and an unidentified purple delphinium, which is possibly a hybrid. Although many species in this genus are karyotypically similar, any variations found among the karyotypes of these Oregon species might be used to identify parental chromosomes in the purple delphinium (proposed hybrid). Meiotic analysis was used to detect structurally heterozygous homologues that …