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Articles 18691 - 18720 of 20608
Full-Text Articles in Entire DC Network
Collagen Fiber Arrangement In Temporo-Mandibular Joint (Tmj) Disks From Human Subjects With Functional Diseases. Scanning Electron Microscopy Investigations, C. Piacentini, C. Marchetti, G. Bernasconi, P. Menghini, U. Baciliero, C. Brusotti
Collagen Fiber Arrangement In Temporo-Mandibular Joint (Tmj) Disks From Human Subjects With Functional Diseases. Scanning Electron Microscopy Investigations, C. Piacentini, C. Marchetti, G. Bernasconi, P. Menghini, U. Baciliero, C. Brusotti
Scanning Microscopy
Twelve articular disks from patients with temporo-mandibular joint (TMJ) arthropathy were studied and compared with two normal disks. Scanning electron microscopy (SEM) examination of the surfaces and of longitudinal and cross-sections of the disks allowed the observation of the arrangement of the collagen fiber component in different parts of the disk. The superficial part of the articular disks appears to be formed by rather compact fibers. The internal portion is usually formed by bundles of collagen fibers in sheets, alternating with isolated fibers arranged in a parallel or irregular way.
In some samples, blood vessels were observed. Our investigations suggested …
Different Forms Of Corrosion Casts, Seyedhossein Aharinejad, Peter Böck
Different Forms Of Corrosion Casts, Seyedhossein Aharinejad, Peter Böck
Scanning Microscopy
We have previously described artifacts in corrosion casts prepared with Mercox®, diluted with methylmethacrylic acid (MMA). Using scanning electron microscopy (SEM) of casts and light microscopy (LM) of tissue sections, we found new forms of artifacts in casts prepared with both undiluted and MMA-diluted Mercox®. When undiluted Mercox® was used, most of the casts did not show artifacts. Artifacts were rarely seen and comprised empty casts consisting of a rim, while endothelial cell nuclear imprints and other vascular wall structures were replicated. Other casts sometimes showed vessels with a fine granular surface or some with conglomerates in their internal structure, …
Influence Of A Corpus Luteum Tissue Extract On Rabbit Ovarian Mesothelial Cells, S. V. Nicosia, R. J. Narconis, B. O. Saunders
Influence Of A Corpus Luteum Tissue Extract On Rabbit Ovarian Mesothelial Cells, S. V. Nicosia, R. J. Narconis, B. O. Saunders
Scanning Microscopy
This study investigates rabbit ovarian mesothelial (OM) cells exposed in vitro to a crude corpus luteum extract (CLE; 60 μg/ml). The growth of OM cells was evaluated by measuring the change in cell number (mean % ± standard error of mean, SEM), the number of cell population doublings (CPD ± SEM), and the cell population doubling time in hours (CPDT ± SEM) after 7.5 days of culture in a serum-poor medium. Quantitative estimates of surface morphology changes were obtained by analyzing the total number (mean no. ± SEM), density (mean no./100 μ.m2 ± SEM), and length-to-diameter ratio (mean L/D …
Distribution Of Ca-Atpases In The Medial Habenula In Mouse, A. Kittel
Distribution Of Ca-Atpases In The Medial Habenula In Mouse, A. Kittel
Scanning Microscopy
The aim of this study was to investigate the distribution of the ecto-Ca,Mg-adenosine-triphosphatases (ecto-Ca,Mg-ATPases) in the medial habenular nucleus. Nerve terminals that seemed to be similar in morphological terms showed a different distribution of enzyme activity. Also, synapses showed a different distribution of enzyme activity. This could be related to the involvement of different neurotransmitters and modulators.
Management Of The Marine Aquarium Fish Fishery, Jonathon Barrington
Management Of The Marine Aquarium Fish Fishery, Jonathon Barrington
Fisheries Management Papers
This Fisheries Management Paper outlines the management arrangements for the Marine Aquarium Fish Fishery that operates in State waters adjacent to Western Australia. These arrangements augment the previous management arrangements for the fishery of 1992 and supersede those arrangements. A limited entry fishery will be established for marine aquarium fish collecting. The other management arrangements are outlined in detail in the paper.
Confocal Fluorescence Ratio Imaging Of Ion Activities In Plant Cells, M. D. Fricker, M. Tlalka, J. Ermantraut, G. Obermeyer, M. Dewey, S. Gurr, J. Patrick, N. S. White
Confocal Fluorescence Ratio Imaging Of Ion Activities In Plant Cells, M. D. Fricker, M. Tlalka, J. Ermantraut, G. Obermeyer, M. Dewey, S. Gurr, J. Patrick, N. S. White
Scanning Microscopy
Fluorescent probes allow measurement of dynamic changes of calcium and pH in living cells. Imaging using confocal scanning laser microscopy provides a route to spatially map these dynamics over time in single optical sections or in 3-D images. We have developed a dual-excitation confocal system to allow ratio measurements of pH and calcium, that compensate for changes in dye distribution, leakage and photobleaching. Application of these techniques to plant tissues is complicated by the difficulty in loading the tissues with dye. We describe a new technique to assist dye loading in intact leaves of Lemna using a pre-treatment with cutinase. …
The General Adaptation Syndrome In Gerbillus, Bridget L. Moore
The General Adaptation Syndrome In Gerbillus, Bridget L. Moore
McCabe Thesis Collection
The General Adaptation Syndrome or the G.A.S. is the term applied to collective responses to physiological stress. It is initiated by any disturbance in the normal balance of the body functions. These responses affect humans, monkeys, and other animals. The three main physiological changes which occur as a result of stress are enlarged adrenals, shrunken lymphatic organs, and bleeding gastrointestinal ulcers. There are also concomitant changes in the hematocrit and the formed elements of blood. In particular, there is usually a decrease in lymphocytes and eosinophils accompanied by the increase in neutrophils and platelets.
Stress is defined as pressure, or …
How Amaranth Grain Affects Total Body Weight And Major Organ Weight In The Mongolian Gerbil, Rhoshonda Montgomery- Conway
How Amaranth Grain Affects Total Body Weight And Major Organ Weight In The Mongolian Gerbil, Rhoshonda Montgomery- Conway
McCabe Thesis Collection
Purpose and Objectives
The purpose of this research is to determine effects of amaranth grain of the body weight and organ weight of the Mongolian gerbil. The literature research indicates that amaranth results in physiological changes that appear to be species-specific rather than general. Since the gerbil is a granivorous animal, it is hypothesized that amaranth will be completely digested and that its nutritional quality will maintain normal to increased growth. While the results of this study cannot be applied to other animals, information has been gained with regard to the influence of amaranth grain on the Mongolian gerbil.
An Analysis Of The Potability Of Water In Logan County, Oscar D. James
An Analysis Of The Potability Of Water In Logan County, Oscar D. James
McCabe Thesis Collection
Recent questions have been raised concerning the drinking water supplying the citizens of Logan County. This study seeks to determine how well Logan County's potable water supply conforms with state and national drinking water standards. Emphasis is placed on the maximum contaminant levels of water supplying the Langston community and surrounding areas. Questions posed to
Management Arrangements For Specimen Shell Collection In Western Australia, Jonathon Barrington
Management Arrangements For Specimen Shell Collection In Western Australia, Jonathon Barrington
Fisheries Management Papers
This Fisheries Management Report outlines the management arrangements in respect of specimen shell collection in Western Australia. It includes a management plan for the Western Australian Specimen Shell Collection Fishery and management arrangements for recreational specimen shell collection.
Role Of Sarcolemma Action Potentials And Excitability In Muscle Fatigue, Edward Michael Balog, Ladora Vaughan Thompson, Robert H. Fitts
Role Of Sarcolemma Action Potentials And Excitability In Muscle Fatigue, Edward Michael Balog, Ladora Vaughan Thompson, Robert H. Fitts
Biological Sciences Faculty Research and Publications
The purposes of this study were to characterize the alterations in the sarcolemma action potential (AP) waveform and sarcolemma excitability as a result of fatiguing stimulation of the frog semitendinosus muscle and to relate these changes to the decrease in the force-generating ability of the muscle. Trains of APs were recorded before and after stimulation (100-ms trains, 150 Hz, 1/s for 5 min). The resting membrane potential (RMP), AP overshoot (OS), and duration at 50% of peak magnitude (DUR) were -84.3 +/- 2.0 mV, 19.5 +/- 1.9 mV, and 1.3 +/- 0.1 ms, respectively, before stimulation. The stimulation protocol caused …
Summer Activity Cost Of Eared Grebes At Mono Lake, Hugh I. Ellis
Summer Activity Cost Of Eared Grebes At Mono Lake, Hugh I. Ellis
Biology: Faculty Scholarship
No abstract provided.
A New Model Species For Cultured Teleost Retinal Cell Studies: Light And Scanning Electron Microscopy, Lori Ann Steinfeldt
A New Model Species For Cultured Teleost Retinal Cell Studies: Light And Scanning Electron Microscopy, Lori Ann Steinfeldt
Undergraduate Honors Capstone Projects
Purpose: To examine retinal horizontal and bipolar cells cultured from goldfish (Carassius auratus), black crappie (Pomoxis nigromaculatus) and bluegill (Lepomis macrochirus) on the light and electron microscope levels; and to compare them with cells from a more established model, the wild white bass (Roccus chrysops). Methods: Retinas from all species were dissociated by methods developed with wild white bass (Dowling et al., 1985). Cell type was identified within the first 3 hr and cells were cultured for up to 2 wk in L-15 medium. At various intervals, cells were fixed in glutaraldehyde, …
Phenotypic Profiles Of Lymphocytes In Adult C57bl/6n Mice Infected With Cryptosporidium Parvum, Diane Rose Bienek
Phenotypic Profiles Of Lymphocytes In Adult C57bl/6n Mice Infected With Cryptosporidium Parvum, Diane Rose Bienek
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
The purpose of this study was to quantitate the populations o f lymphocytes in the spleens and intestines of normal and immunosuppressed adult C57BL/6N mice that were noninfected or infected with Cryptosporidium parvum. This was accomplished by using the following methodologies: immunohistochemistry, ELISA-spot assay, and flow cytometry.
Mice in groups 1 and 2 were immunosuppressed, but only group 2 was infected. Mice in group 3 were only infected, whereas group 4 served as the normal control. Mice were immunosuppressed with dexamethasone (DEXI at a dosage of 125µg/mouse/day. Infected mice received 106 oocysts per os. The numbers of lymphocytes were …
The Preparation Of Cultured Cells For X-Ray Microanalysis, Alice Warley
The Preparation Of Cultured Cells For X-Ray Microanalysis, Alice Warley
Scanning Microscopy
X-ray microanalysis of cells in culture is being used increasingly for the study of relationships between element (ion) content and cell function. There is, however, no one single method which can be used for the preparation of all different cell types for study by microanalysis. Cells in suspension are usually concentrated by centrifugation, before cryofixation, cryosectioning, and freeze drying. On the other hand cells grown as monolayers are more often studied as whole cell mounts, which are washed to remove the external medium before cryofixation and freeze drying. The alternative approach, sectioning of cell monolayers is rarely used. Some of …
Morphological And Genetic Variation Among Three Populations Of The Endangered San Salvador Rock Iguana, Cyclura Rileyi Rileyi, Brent Goodge, David Brouhard, William Hayes, Danette Hayes
Morphological And Genetic Variation Among Three Populations Of The Endangered San Salvador Rock Iguana, Cyclura Rileyi Rileyi, Brent Goodge, David Brouhard, William Hayes, Danette Hayes
Capstone Research Projects
No abstract provided.
The Effects Of Water Deprivation And Conditioned Taste Aversion On A Cognitive Task In Laboratory Rats, Tisha L. Salary
The Effects Of Water Deprivation And Conditioned Taste Aversion On A Cognitive Task In Laboratory Rats, Tisha L. Salary
Capstone Research Projects
No abstract provided.
Molecular Analysis Of Ovary Specific Cdnas From Galleria Mellonella, Veeraramini S. Rajaratnam
Molecular Analysis Of Ovary Specific Cdnas From Galleria Mellonella, Veeraramini S. Rajaratnam
Dissertations (1934 -)
To study the regulation of sex-specific gene expression during oogenesis, a vitellogenic ovariole cDNA library was constructed and differentially screened with ovary and male pharate pupal total cDNAs. Six classes of ovary specific clones were isolated. Clones, F11, F20 and N23 represent 1.1, 2.0 and 2.3 kb ovary specific transcripts. In situ hybridization and developmental Northern analysis showed that F11 and F20 transcripts are limited to vitellogenic follicle cells. N23 transcripts are present in the pre-vitellogenic and vitellogenic nurse cells, and they persist in choriogenic follicles and early embryos suggesting that N23 may represent a maternal message. The 0.95 kb …
The Microvasculature Of The Larynx: A Scanning Electron Microscopic Study, Peter Franz, Seyedhossein Aharinejad
The Microvasculature Of The Larynx: A Scanning Electron Microscopic Study, Peter Franz, Seyedhossein Aharinejad
Scanning Microscopy
In ten adult guinea pigs, the microvascular architecture of the larynx was evaluated using microvascular corrosion casts and scanning electron microscopy. The vocal cords were provided with a subepithelial capillary network. The capillaries, freely anastomosing with each other, were supplied and drained via strongly undulating arteries and veins. The undulation of the latter vessels may explain their adaptability to volume changes of the larynx during phonation. The vasculature of the internal perichondrium of the thyroid cartilage was interrupted at the anterior commissure where an avascular zone was present at the origin of the vocal cords. This avascular area is common …
Ultrastructural Changes Of The Vestibular Sensory Organs After Streptomycin Application On The Lateral Canal, Kwang-Sun Lee, Robert S. Kimura
Ultrastructural Changes Of The Vestibular Sensory Organs After Streptomycin Application On The Lateral Canal, Kwang-Sun Lee, Robert S. Kimura
Scanning Microscopy
Early changes in the vestibular sense organs resulting from the application of a streptomycin sulfate soaked Gelfoam® pledget on the fenestra of the lateral semicircular canal were studied by transmission and scanning electron microscopy. Three days after the application, lesions were present in the central part of the lateral crista. The type I sensory cells were more affected than the type JI cells. These sensory cells showed mitochondrial swelling, cytoplasm protrusion at the cell apex, inclusion of multiple vacuoles, fusion or loss of stereocilia, and pyknotic nuclei. Seven days after the drug application, the sensory cell damage extended to all …
Phylogenetic Analysis Of Segment 10 From African Horsesickness Virus And Cognate Genes From Other Orbiviruses, Rafael O. De Sá, Marla Zellner, Marvin J. Grubman
Phylogenetic Analysis Of Segment 10 From African Horsesickness Virus And Cognate Genes From Other Orbiviruses, Rafael O. De Sá, Marla Zellner, Marvin J. Grubman
Biology Faculty Publications
Utilizing the reverse transcriptase-polymerase chain reaction (RT-PCR) procedure, we have synthesized full-length copies of segment 10 from African horsesickness virus (AHSV) serotypes 1,4 and 8. The genes were cloned, sequenced and compared with the sequence of the cognate gene from AHSV serotypes 3 and 9. Sequences were analyzed to assess evolutionary relationships among serotypes using cladistics. Based on this analysis the data support a close relationship between serotypes 4 and 9 and between serotypes 1 and 8 and a closer relationship of serotype 3 to the 4 and 9 group.
X-Ray Microanalysis Of Endocrine, Exocrine And Intestinal Cells And Organs In Culture: Technical And Physiological Aspects, Romuald Wróblewski, Joanna Wroblewski
X-Ray Microanalysis Of Endocrine, Exocrine And Intestinal Cells And Organs In Culture: Technical And Physiological Aspects, Romuald Wróblewski, Joanna Wroblewski
Scanning Microscopy
In the present study methods for preparation of cultured cells and organ cultures for analytical electron microscopy are investigated. These methods allow qualitative and quantitative analysis of mobile ions in combination with biochemical or morphological studies. Cultured cells can be easily prepared for analytical microscopy and therefore use of in vitro systems for X-ray microanalysis has increased over the last few years. Two major, anhydrous preparation techniques, by which loss or redistribution of ions is minimized, were used: (1) Cells were cryosectioned and analysis carried out on freeze-dried sections obtained from frozen cell monolayers, pelleted cells or organ cultures. (2) …
Microvascular Pattern Of The Retina In The Japanese Monkey (Macaca Fuscata Fuscata), Shigenori Okada, Yoshikuni Ohta
Microvascular Pattern Of The Retina In The Japanese Monkey (Macaca Fuscata Fuscata), Shigenori Okada, Yoshikuni Ohta
Scanning Microscopy
The microvascular architecture of the retina in the Japanese monkey was revealed using scanning electron microscopy of microvascular corrosion casts.
At the optic nerve disc, the central retinal artery radiated to four primary retinal arterioles: the superior and inferior temporal arterioles and superior and inferior nasal arterioles. A dense retinal capillary network showed regional differences in density. The capillary networks observed were divided in four parts: the optic nerve disc, macula, equator, and ora serrata. At the optic nerve disc, the network was a multi-laminar structure containing the radial peripapillary capillaries in parallel with the nerve fibers at the innermost …
Induction Of Selective Inner Hair Cell Damage By Carboplatin, S. Takeno, R. V. Harrison, R. J. Mount, M. Wake, Y. Harada
Induction Of Selective Inner Hair Cell Damage By Carboplatin, S. Takeno, R. V. Harrison, R. J. Mount, M. Wake, Y. Harada
Scanning Microscopy
Carboplatin (diammine [1,1 cyclobutane dicarboxylato (2)-0,0'] platinum) is an anti-cancer agent which can be toxic to the inner ear. We have explored the nature of this ototoxicity in the chinchilla. In this species, initial degenerative changes appear to be restricted to the inner hair cell (IHC) regions of the organ of Corti. This finding is intriguing and unusual since all other known ototoxic drugs, such as aminoglycosides, are predominantly associated with outer hair cell damage.
In the present study, the mechanism of ototoxicity was investigated by comparing two different routes of carboplatin administration. Carboplatin was administered either intravenously (i.v.) or …
Effects Of Competition And Predation On Prothonotary Warblers And House Wrens Nesting In Eastern Iowa, Timothy Brush
Effects Of Competition And Predation On Prothonotary Warblers And House Wrens Nesting In Eastern Iowa, Timothy Brush
School of Integrative Biological & Chemical Sciences (Formerly Dept. of Biology)
In a fragmented midwestern floodplain forest, a small Prothonotary Warbler (Protonotaria citrea) population experienced high competition with House Wrens (Troglodytes aedon) and mammalian nest predation in 1988-89. Despite the provision of 3 types of nest boxes and higher water levels, Prothonotary Warblers did not nest successfully and decreased in the fragmented forest in 1990-91. House Wrens used >90% of the nest boxes in both years. Wren territories doubled within the nestbox area, while remaining constant on an unmanipulated area. In contrast, a larger warbler population had high nesting success during 1990-91 in a relatively unfragmented, wetter forest tract. Such forests, …
Ultrastructural Observations Of The Argonaut Shell, P. R. Mitchell, P. P. Phakey, W. A. Rachinger
Ultrastructural Observations Of The Argonaut Shell, P. R. Mitchell, P. P. Phakey, W. A. Rachinger
Scanning Microscopy
An examination of the ultrastructure of the shell of the cephalopod Argonauta Nodosa was carried out using scanning electron microscopy, transmission electron microscopy and polarised light microscopy. The structure of the Argonaut shell was found to consist of an inner and outer prismatic layer separated by a thin central zone which was sparsely occupied by spherulitic crystals. Fluctuations in the width and porosity of the central zone resulted in changes in the shell's opacity and gave rise to the fibrous lines visible in the structure. The central zone was the region of initial growth and was the nucleating point for …
Electron Probe X-Ray Microanalysis Of Epithelial Cells: Aspects Of Cryofixation, Karl Zierold, Hartmut Hentschel, Frank Wehner, Armin Wessing
Electron Probe X-Ray Microanalysis Of Epithelial Cells: Aspects Of Cryofixation, Karl Zierold, Hartmut Hentschel, Frank Wehner, Armin Wessing
Scanning Microscopy
Content and distribution of diffusible ions in epithelial cells were studied by scanning transmission electron microscopy and energy dispersive electron probe X-ray microanalysis of freeze-dried cryosections from trout kidney, rat liver and Malpighian tubules of Drosophila larvae. Cryofixation of small excised kidney and liver samples by rapid immersion into liquid propane resulted in intracellular K/Na-ratios < 1. In contrast, K/Na-ratios > 7 were obtained after in situ cryofixation by means of a cryopunching device which allows tissue pieces to be frozen during excision from the intact organ. Isolated hepatocytes cryofixed in a small droplet of culture medium had a K/Na-ratio of 3.7. After culturing the hepatocytes, …
Radiation-Induced Fibrosis: The Structure/Function Relationship, J. C. Murray
Radiation-Induced Fibrosis: The Structure/Function Relationship, J. C. Murray
Scanning Microscopy
Fibrosis is a frequent complication of therapeutic radiation delivered to organ sites such as the thorax and pelvic region. We investigated the relationship between function, and biochemical and structural changes in the lung and colon of CBA mice irradiated with 240 kV X-rays. Progressive changes in lung function, as evidenced by increased breathing rates were observed out to 6 months post-irradiation. Biochemical studies demonstrated increased metabolism (synthesis and breakdown) of collagen around 6 months after irradiation, but provided no evidence of net collagen accumulation. Analysis of collagen isotypes revealed a slight increase in the ratio of types I and Ill. …
The Composition And Social-Organization Of Mixed-Species Flocks In A Tropical Deciduous Forest In Western Mexico, Richard L. Hutto
The Composition And Social-Organization Of Mixed-Species Flocks In A Tropical Deciduous Forest In Western Mexico, Richard L. Hutto
Biological Sciences Faculty Publications
I recorded the flocking propensity of birds within a tropical deciduous forest in western Mexico during the nonbreeding season, and determined the species composition of 57 mixed-species, canopy insectivore flocks. Each of 27 canopy insectivore species present on the study area was observed foraging in mixed-species flocks on at least half of the occasions that it was detected on bird surveys. The proportion of flocks within which a given species was detected could be predicted on the basis of its index of abundance, as determined from independently derived point count data. Therefore, flocks are not comprised of a special subset …
Optical Methods For Imaging Ionic Activities, Roger B. Moreton
Optical Methods For Imaging Ionic Activities, Roger B. Moreton
Scanning Microscopy
Optical fluorescence is characteristic of molecules and their environment, and dyes can be made whose fluorescence is altered by reversible binding to specific ions. By introducing these into the cytosol, fluorescence microscopy can be used to form dynamic images of ionic activities in living cells under experimental manipulation. Optical fluorescence spectra are broad-band, and if specific ion binding alters the wavelength of maximal excitation or emission, quantitative measurements can be made from the ratio of images taken at two different wavelengths, eliminating errors due to spatial variations in dye concentration and optical path-length. This method is analogous to continuum normalisation …