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Articles 211 - 240 of 367
Full-Text Articles in Biology
A Determination Of Parentage, Mating System, And Genetic Diversity In A Captive Population Of The Straw-Colored Fruit Bat (Eidolon Helvum), Jan Zinck
Dissertations and Theses
Small populations tend to lose genetic variability. The magnitude of this loss is influenced by the number of founding individuals, the genetic diversity of the founders, and the species mating system. Genetic variability is the basis of adaptive evolution, and the loss of genetic variability may have harmful effects on development, growth, and survival. Therefore, a primary management goal for small, captive populations is the retention of genetic variability. Of considerable importance to conservation biology is the determination of parentage, from which mating, genetic, and demographic information can be derived. Microsatellites provide a robust molecular evolutionary tool for the study …
Profiles Of The Highly Invasive Plants In Oregon Including Lists Of Oregon’S Invasive And Naturalized Plants, Rebekah Jane Harper
Profiles Of The Highly Invasive Plants In Oregon Including Lists Of Oregon’S Invasive And Naturalized Plants, Rebekah Jane Harper
Dissertations and Theses
The study and control of invasive species are important issues in restoration ecology and land management. Invasive species are among the top contributors to habitat degradation worldwide. Unfortunately, information concerning invasive species and methods for their control is limited and widely scattered throughout the literature.
A comprehensive list of the naturalized and invasive species found in Oregon is important for monitoring invasive and potentially invasive species. It also provides a base of information for people interested in investigating invasive species; however, no such state-wide list existed for Oregon before this work.
Profiles for highly invasive species should provide information concerning …
Reproductive Biology Of Melilotus Officinalis (L.) Lam (Fabaceae: Papilionoideae): Morphology, Seed/Ovule Ratios And Ovule Abortion Patterns, Susan Lee Schouten
Reproductive Biology Of Melilotus Officinalis (L.) Lam (Fabaceae: Papilionoideae): Morphology, Seed/Ovule Ratios And Ovule Abortion Patterns, Susan Lee Schouten
Dissertations and Theses
Melilotus officinalis, an introduced herbaceous species within the Papilionoideae, has a fixed ovule abortion pattern. In its primarily single-seeded, indehiscent fruits, with an average of 6.98 ovules/fruit, this species matured the basal-most ovule in 67.63% and the second basal-most ovule in 24.22% of the fruits studied. This pattern contrasts with other legumes studied, which abort the basal-most ovules or those at either end of the fruit. Workers propose interaction between two opposing gradients--that of maternal resources from the basal end of the fruit and of fertilization from the stylar end. Several lines of evidence indicate that all ovules are …
Measurement Of The Cross-Sectional Area Of The Nasal Passages Of Nine Species Of Modern Odontoceti With Implications For Comparative Physiology And The Paleophysiology Of The Dinosauria, Eric Paul Katz
Dissertations and Theses
In search of evidence for or against the endothermic dinosaur hypothesis, a recent study by Ruben et al. (1996) revealed that endotherms tend to have larger nasal cross-sectional areas than ectotherms of the same mass. The reason offered for this observation was that larger nasal passages are needed to house the complex respiratory turbinates possessed by endotherms. Whales were excluded from the study on the grounds that they have no nasal turbinates. In the present study, the cross-sectional area of the nasal passages of nine species of Odontoceti were measured by the use of latex casts. The regression of log …
Chemical Communication Of Estrous Cycle Status And Change In Social Behaviors With Reproductive State In Captive Female Asian Elephants, Elephas Maximus, Barbara Elaine Slade
Chemical Communication Of Estrous Cycle Status And Change In Social Behaviors With Reproductive State In Captive Female Asian Elephants, Elephas Maximus, Barbara Elaine Slade
Dissertations and Theses
Elephants use several well-developed sensory systems for communicating within and between social groups. Female elephants sniff, touch and flehmen to the urine and genitals of herdmembers. In addition, communication through social behaviors is prevalent. Female elephants frequently communicate through affiliate tactile and aggressive behaviors. Furthermore, although female elephants are not known to display behavioral signs of estrus, these females exhibit a tail slapping behavior that may be an implement for dispersing chemical signals to conspecifics or nearby male elephants.
The present study addresses two areas of research. The purpose of part one was first, to determine if female Asian elephants …
Photoadaptation Rate Of Synechococcus Wh7803 Cultures At Two Iron Concentrations, Jon Daniel Moulton
Photoadaptation Rate Of Synechococcus Wh7803 Cultures At Two Iron Concentrations, Jon Daniel Moulton
Dissertations and Theses
The marine cyanobacterium Synechococcus WH7803 adapts to changes in light intensity by changing its photosynthetic physiology. This work is a study o f the rate o f photoadaptation of Synechococcus WH7803 in laboratory cultures. Cultures were shifted from constant 8 µEm-2s-1 light to constant 80 µEm-2s-1 light, from constant 80 µEm-2s-1 light to 8 µEm-2s-1 light and from different light regimes to a single fluctuating light regime. The response of high iron cultures grown in modified aquil culture medium at 5*10-6M Fe was compared with the …
Abundance And Seasonal Distribution Of The Marbled Murrelet In Puget Sound And Hood Canal In Fall And Winter, Richard Anthony Jensen Merizon
Abundance And Seasonal Distribution Of The Marbled Murrelet In Puget Sound And Hood Canal In Fall And Winter, Richard Anthony Jensen Merizon
Dissertations and Theses
The greater Puget Sound area is home to a diversity of seabirds, however with encroaching human recreational and economic use of these areas these birds are facing unique threats. It is vitally important that we understand where these seabirds occur in order to minimize the risks associated with human influences. Intensive and extensive transects were used to collect data on seasonal distribution and abundance of seabirds, specifically marbled murrelets (Brachyramphus marmoratus), in Puget Sound and Hood Canal. Surveys were conducted from the water during the fall and winter in 1995 and 1996 and summer of 1997. Marbled murrelets were abundant …
Temperature Sensitivity Of El Tor 01, Classical 01, And 0139 Vibrio Cholerae, Michelle Angela O'Neill
Temperature Sensitivity Of El Tor 01, Classical 01, And 0139 Vibrio Cholerae, Michelle Angela O'Neill
Dissertations and Theses
Vibrio cholerae has long been recognized as the causative agent of the disease cholera, but what has only become evident in recent years is the role of the environment in cholera. The cholera bacterium is found autochthonously in the marine and estuarian environment, and if there is any hope of controlling the disease the environmental aspects must be understood.
The central questions addressed in this study were how bacterial survival was influenced by temperature and the role that available nutrients play in V. cholerae survival. Survival of three different V. cholerae strains [classical (01); El Tor (01), and El Tor …
Construction And Analysis Of Mutant Hsv-1 Viruses Having Mutations In The Yy1 And/Or Sp1 Binding Sites Of The Glycoprotein D (Gd) Gene Promoter, Sabine Ludwig
Dissertations and Theses
The purpose of this study was to construct and analyze four recombinant herpes simplex virus type 1 (HSV-1) viruses having mutations in the YY1 and/or Sp1 binding sites of the glycoprotein D (gD) gene promoter and a control virus containing a wild type (wt) gD promoter. The YY1 and Sp1 binding sites in the HSV-1-gD gene promoter have been shown in earlier in vitro experiments to be essential for virus-induced gD gene expression with Sp1 playing the major role. The first part of my project required the construction of four different plasmids containing a HSV-1 sequence that included the gD …
Age Related Changes In The Activity And The Responsiveness Of The Renin-Angiotensin System In The 15 Month Old Rat, Michele Mckee Thompson
Age Related Changes In The Activity And The Responsiveness Of The Renin-Angiotensin System In The 15 Month Old Rat, Michele Mckee Thompson
Dissertations and Theses
Progressive deterioration of renal function is one consequence of aging. Glomerular maladaptation is one aspect of this and includes increased glomerular capillary hypertension and a reduced ultrafiltration coefficient, which can lead to glomerular sclerosis and proteinuria. In the aging rat, angiotensin converting enzyme inhibitors (CEI) lower proteinuria (UprotV) and decrease glomerular sclerosis (2, 18, 24, 45). Accordingly, alterations in the circulating and renal renin-angiotensin system (RAS) are hypothesized to play a role in the pathogenesis of renal disease in the aging rat. Previous studies using rat models have demonstrated a lower responsiveness to converting enzyme inhibitor treatment in …
Whole Body I=In Vivo Vascular Compliance In Two Amphibians, Bufo Marinus And Rana Cate, Todd Micheal Hoagland
Whole Body I=In Vivo Vascular Compliance In Two Amphibians, Bufo Marinus And Rana Cate, Todd Micheal Hoagland
Dissertations and Theses
The mean circulatory filling pressure (MCFP), vascular compliance (C) and unstressed volume (USV) were measured in Bufo marinus and Rana catesbeiana, using an in vivo preparation. Capacitance curves were constructed by varying total vascular volume and then measuring MCFP. These capacitance curves enable the extrapolation of USV and the measurement of vascular compliance. The MCFP, C, and USV were 8.6 ± 0.2 (mmHg), 3.7 (ml· mmHg-1 · kg- 1 ) and 2.5 (ml), respectively, in B. marinus. The MCFP, C, and USV were 9.5 ± 0.1 (mmHg), 2.2 (ml· mmHg-1 · kg- 1 ) and 14.2 (ml), respectively, …
Whole Body In Vitro Hydraulic Conductivity And Transcapillary Filtration In Two Amphibians, Bufo Marinus And Rana Catesbeiana, Thomas Vincent Hancock
Whole Body In Vitro Hydraulic Conductivity And Transcapillary Filtration In Two Amphibians, Bufo Marinus And Rana Catesbeiana, Thomas Vincent Hancock
Dissertations and Theses
The capillary filtration coefficient (CFC) and isovolumetric capillary pressure (Pci) were measured in Bufo marinus and Rana catesbeiana, using a gravimetric technique on an in vitro preparation while perfusing with Ringers and 0.1 g·100 ml-1 bovine serum albumin Estimates of pre- and post-capillary resistance were obtained from Bufo; the post- to pre-capillary resistance ratio was found to be 0.18, which was used to estimate capillary pressure. CFC was found to be 6.68 ± 0.51 and 5.07 ± 0.23 ml·min-1·kg-1·mmHg-1 and Pci was found to be 7.4 and 6.3 mmHg in …
The Effect Of Lymph Sac Pressure On Lymph Heart Pressure Development In The Toad Bufo Marinus, Michael Georgitsis
The Effect Of Lymph Sac Pressure On Lymph Heart Pressure Development In The Toad Bufo Marinus, Michael Georgitsis
Dissertations and Theses
Lymph hearts play an important role in blood volume regulation in anurans by controlling the movement of fluid from the lymphatic spaces to the vasculature. The anatomical continuity between lymph sacs and lymph hearts predicts a coupling of pressure between the two structures which may represent a physical basis for lymph heart regulation. The precise relationship between lymph heart pressure and lymph heart output was not examined so that conclusions regarding changes in work performed by the hearts as a result of changing lymph sac pressure could not be made. However, increases in lymph sac pressure led to increases in …
A Pouplation Genetic Study Of Wild Bottlenose Dolphins (Tursiops Truncatus) In Matagorda Bay, Texas, Joel Stephen Lenox
A Pouplation Genetic Study Of Wild Bottlenose Dolphins (Tursiops Truncatus) In Matagorda Bay, Texas, Joel Stephen Lenox
Dissertations and Theses
A long-term photoidentification study was initiated in response to an unusually high incidence of bottlenose dolphin mortality between Corpus Christi and Matagorda Bays, Texas. Blood samples from 36 captured and released animals were analyzed using three genetic techniques; mtDNA haplotyping, nuclear DNA fingerprinting and electrophoretic analysis of hemoglobin. Two Hinf I mtDNA haplotypes previously described in bottlenose dolphins from other locations within the Gulf of Mexico were discovered. Similarity Indices (SI) were calculated based on nuclear DNA fingerprinting data. These SI values were used as a relative measure of relatedness between two individuals run on the same gel. Means of …
Ovarian Steroid Regulation Of Tryptophan Hydroxylase Enzyme Level In The Midbrain Raphe In Ovariectomized Guinea Pigs, Zhidong Lu
Dissertations and Theses
Progesterone stimulates prolactin secretion in estrogen ( estradiol-17-~)primed monkeys and guinea pigs. It is hypothesized that the serotonin neural system plays a pivotol role in mediating the effect of progesterone on prolactin secretion. Indeed, progesterone, but not estrogen, increases serotonin levels in the midbrain raphe in guinea pigs. However, estrogen alone stimulates gene expression of the rate-limiting enzyme for serotonin synthesis, tryptophan hydroxylase (TPH), and progesterone supplement to the estrogen regimen has no additive effect, as indicated by TPH mRNA levels in monkeys. The discrepancy between ovarian steroid effects on the TPH mRNA level and the serotonin level might be …
The Role Of The Hepatic Vagus In The Pathogenesis Of Fever, Christopher Todd Simons
The Role Of The Hepatic Vagus In The Pathogenesis Of Fever, Christopher Todd Simons
Dissertations and Theses
Recent evidence has suggested a role of vagal afferents in the pathogenesis of fever. Although bilateral truncal subdiaphragmatic vagotomy has been shown to attenuate the febrile response to lipopolysaccharide (LPS) and interleukin-1, no study has yet been able to verify which of the five subdiaphragmatic vagal branches (viz., the anterior and posterior celiac branches, the anterior and posterior gastric branches, and the hepatic branch) is responsible for communicating this signal. The present study tested the hypothesis that the hepatic vagal branch mediates pyrogenic signals from the periphery to the brain. Male Wistar rats underwent one of four selective …
Structural And Successional Analysis Of Woodland Vegetation In Tualatin Hills Nature Park, Christopher J. Dobson
Structural And Successional Analysis Of Woodland Vegetation In Tualatin Hills Nature Park, Christopher J. Dobson
Dissertations and Theses
Tualatin Hills Nature Park is an urban woodland located in Beaverton, Oregon. The park is owned and managed by Tualatin Hills Park & Recreation District. Vegetation in the park is in a state of secondary succession following a long history of disturbance. The site provided an excellent opportunity to study the recovery of a natural woodland in an urban setting in the northern Willamette Valley.
The purpose of this study was to analyze the species composition, structure, and successional trends of the woodland vegetation in Tualatin Hills Nature Park. A secondary purpose was to determine if there were any natural …
The Periphyton Community Of A Second Order Subalpine Stream Following Salmon Carcass Decomposition, Jonathan Micheal Honea
The Periphyton Community Of A Second Order Subalpine Stream Following Salmon Carcass Decomposition, Jonathan Micheal Honea
Dissertations and Theses
To protect and manage Pacific Northwest salmonid stocks, sound management programs must be developed that incorporate knowledge of the ecological processes critical to their survival. One such process is the nutrient dynamic in headwater spawning streams. It is essential that we understand the trophic relationships among the spawners, the I to 3 year-old juveniles, the invertebrates, and the primary producers in these streams.
The hypothesis that I tested is that photoautotrophic production increases due to the decomposition of salmon carcasses. Increased primary production would stimulate the production of invertebrates which are an important food resource of juvenile salmonid species. The …
Purification And Characterization Of Catalase From Enterococcus Faecalis, Zhenghong Zhu
Purification And Characterization Of Catalase From Enterococcus Faecalis, Zhenghong Zhu
Dissertations and Theses
Catalase is an important biological enzyme that most organisms employ during aerobic growth to catalyze the decomposition of hydrogen peroxide, a toxic reduction product of oxygen, into water and molecular oxygen. Traditionally, the bacterium Enterococcus faecal is is considered to have no cytochrome system and to be catalase negative. However, certain strains of E. subsequent studies have shown that faecalis are capable of producing catalase when grown aerobically in a medium containing hematin.
The goals of this study were to purify and characterize catalase from a clinical strain of E. faecalis. The organisms were grown under aerobic conditions in a …
Investigation Of Transactivation Of The Human C-Myc Gene By Herpes Simplex Virus Type 1, Xian Wu
Investigation Of Transactivation Of The Human C-Myc Gene By Herpes Simplex Virus Type 1, Xian Wu
Dissertations and Theses
The purpose of this investigation was to identify the regulatory elements involved in the transactivation of the human c-myc gene by herpes simplex virus type-1 (HSV-1). This study mainly focused on a major c-myc promoter P2 (Fig. 1). Transient expression assays were carried out with a reporter plasmid, that contained either a wild type (+66wt c-myc) or mutant (+66 mt E2F, +66mt CT -I2) c-myc promoter fused to the chloramphenicol acetyltransferase (CAT) gene, cotransfected with effector plasmids that contained the HSV-1 immediate early (IE) genes ( encoding IE proteins, ICP4, ICP0, ICP27). The transient expression assays revealed …
Chemical Communication In House Mice (Mus Musculus): Can They Recognize Gender From The Anogenital, Harderian Gland Or Mouth/Nose Odor?, Dawn Michele Andrews
Chemical Communication In House Mice (Mus Musculus): Can They Recognize Gender From The Anogenital, Harderian Gland Or Mouth/Nose Odor?, Dawn Michele Andrews
Dissertations and Theses
Identifying the sensory systems animals employ to communicate chemically and the function of the chemical signals facilitates further understanding of chemical communication. Increased knowledge of how animals use the olfactory and vomeronasal systems in order to interpret the meaning of body odors will aid in developing a more detailed organization of chemosensory pathways. The message that each body odor contains can change from species to species.
The purpose of this thesis was to study three previously untested body odors in house mice (M. musculus) for their role in gender recognition of conspecifics. These odors are the anogenital (feces, …
Evaluation Of A Rapid-Screening Toxicity Test Using The Ciliate, Colpoda Inflata (Stokes): Sensitivity And Bioavailability To Model Compounds, Daria Galina Mochan
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
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
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
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 …
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
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
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
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
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 …