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Articles 421 - 450 of 519
Full-Text Articles in Biology
Electron Microscopic Study Of The Perivascular Region Of The Pineal Gland Of The Early Post-Hatching Domestic Fowl With Emphasis On Exogenously Produced Lymphocyte Emigration, Christopher N. Casciano
Electron Microscopic Study Of The Perivascular Region Of The Pineal Gland Of The Early Post-Hatching Domestic Fowl With Emphasis On Exogenously Produced Lymphocyte Emigration, Christopher N. Casciano
Master's Theses
No abstract provided.
Histological Evaluation Of Gingiva In Complete Crown Restorations, Meera Mahajan
Histological Evaluation Of Gingiva In Complete Crown Restorations, Meera Mahajan
Master's Theses
No abstract provided.
Populations Of Lepomis Auritus (Redbreast Sunfish) In A Thermally Influenced Section Of The James River, Virginia, John Rawls Saecker
Populations Of Lepomis Auritus (Redbreast Sunfish) In A Thermally Influenced Section Of The James River, Virginia, John Rawls Saecker
Master's Theses
From October 1971 - September 1973, electrofishing was used to collect 1004 specimens of Lepomis auritus (year classes 0 - V) from a thermally influenced section of the James River near Blemo Bluff, Virginia. Collections of fish from the natural and heated water temperature habitats were analyzed as to year classes, season, length and sex.
The Effects Of Topical Nitrogen Mustard On The Pigment System In Pet/Wmr Mouse Epidermis, Ronald Lee Salisbury
The Effects Of Topical Nitrogen Mustard On The Pigment System In Pet/Wmr Mouse Epidermis, Ronald Lee Salisbury
Master's Theses
Miniature melanocytes have been observed scattered among the typical melanocytes in the skin of the PET/Wmr mouse strain, They are weakly DOPA reactive and their cell bodies and nuclei are one quarter the size of those in typical melanocytes, Both populations reach a peak during the first postnatal week and then gradually disappear within the following three weeks. The miniatures appear very early and are among the last cells to disappear. During the first postnatal week, their population remains relatively constant against a radically changing population of typical melanocytes. That they may represent a stage in the development of typical …
Melanin In The Longnose Gar, Lepisosteus Osseus, George William Minson
Melanin In The Longnose Gar, Lepisosteus Osseus, George William Minson
Master's Theses
Examination was made of the melanophores of three Lepisosteus osseus (longnose gar), one dark, one intermediate, and one normal in pigmentation. Melanophore counts were made per mm2 from anterior, mid, and posterior areas of both the dorsal and ventral surfaces of each of the three fish. The data were tested with a four-factor analysis of variance. By microscopic examination the melanophores were classified as to branching in the sample areas. Neither number of melanophores nor degree of branching explained divergence in pigmentation. However, divergence was attributed to the melanosome color and concentration in the melanophores.
Effects Of The Toxins Of The Ectoproct, Lophopodella Carteri, On Oxygen Consumption In Gill Tissues Of The Bluegill, Lepomis Macrochirus, Barbara Harper Green
Effects Of The Toxins Of The Ectoproct, Lophopodella Carteri, On Oxygen Consumption In Gill Tissues Of The Bluegill, Lepomis Macrochirus, Barbara Harper Green
Master's Theses
Large and small bluegill, Lepomis macrochirus, were exposed to homogena tes of Lophopodella carteri, an ectoproct that contains substances toxic to some gilled vertebrates. Oxygen consumption tests on the excised gill tissues of the bluegill indicated that the ectoproct toxins caused a lowering of oxygen consumption of the gill tissues. Oxygen consumption of the gill tissues of the smaller fish was reduced to a greater extent than that of larger fish. An inverse relationship was found be tween the temperature of the medium and the period of time for death to occur. It is proposed that the toxins cause physiological …
Actions Of Mammalian Gonadotrophins In Female Anolis Carolinensis (Green Anole) Within Selected Parameters Of Photoperiod And Temperature, Frank Loving Holt Jr.
Actions Of Mammalian Gonadotrophins In Female Anolis Carolinensis (Green Anole) Within Selected Parameters Of Photoperiod And Temperature, Frank Loving Holt Jr.
Master's Theses
The effects of either porcine FSHt equine LH, or both combined upon the pregametic a.nd gametic phases of the ovarian cycle of Anolis carolinensis {green anole)were investigated in animals maintained under one of three photothermal. regimens: 3 hours light at 15 C; 14 hours light at 15 C; or 14 hours light at 32 C.
Increases in pre-vitellogenic follicle diaaeter and ovarian weight were significantly greater at 32 C than at 15 c. A trend towards decreased numbers of atretic follicles with increased gonadotrophin dosage occurred in response to 14 hours light at 32 C. Gonadotrophin dosages which stimulated vitello …
Effects Of The Toxins Of Lophopodella Carteri (Ectoprocta), On Blood Lactate And Electrolytes Of Lepomis Macrochirus (Bluegill), Robert Fisher Dance
Effects Of The Toxins Of Lophopodella Carteri (Ectoprocta), On Blood Lactate And Electrolytes Of Lepomis Macrochirus (Bluegill), Robert Fisher Dance
Master's Theses
Specimens of bluegill (Lepomis macrochirus) were exposed to homogenates of Lophopodella carter, an ectoproct that contains substances toxic to some gilled vertebrates. The homogenates caused significant decreases in blood Na+ and Cl - and a significant increase in lactate. Potassium levels were unaffected. It is proposed that these changes in blood. properties were caused by damage to ion transport mechanisms of the gill epithelium.
Isozyme Patterns In The Life-Cycle Of The Free-Living Nematode, Panagrellus Silusiae, Mary Ilze Brokans
Isozyme Patterns In The Life-Cycle Of The Free-Living Nematode, Panagrellus Silusiae, Mary Ilze Brokans
Master's Theses
No abstract provided.
Lipid And Protein Energy Utilization In Starved Bluegill Sunfish (Lepomis Macrochirus), Nancy H. Siemon
Lipid And Protein Energy Utilization In Starved Bluegill Sunfish (Lepomis Macrochirus), Nancy H. Siemon
Master's Theses
No abstract provided.
The Effect Of Calcium Sulfide On The Hactchability Of Chironomous Riparius Meigen Eggs, Gerald S. Wegner
The Effect Of Calcium Sulfide On The Hactchability Of Chironomous Riparius Meigen Eggs, Gerald S. Wegner
Master's Theses
No abstract provided.
The Effect Of Nematode Age On Trap Formation In The Nematophagous Fungus Arthrobotrys Conoides, Mary Lou Tortorello
The Effect Of Nematode Age On Trap Formation In The Nematophagous Fungus Arthrobotrys Conoides, Mary Lou Tortorello
Master's Theses
No abstract provided.
The Effects Of Language On The Mediation Of Temporally Based Concepts With Deaf And Blind Children, Gregory Doyle
The Effects Of Language On The Mediation Of Temporally Based Concepts With Deaf And Blind Children, Gregory Doyle
Master's Theses
No abstract provided.
Thermal And Hypoxic Induced Alterations Of Selected Red Cell Organophosphates In The Female Fresh-Water Turtle, Pseudymys Scripta Elegans, Daniel Culking
Thermal And Hypoxic Induced Alterations Of Selected Red Cell Organophosphates In The Female Fresh-Water Turtle, Pseudymys Scripta Elegans, Daniel Culking
Master's Theses
No abstract provided.
Parasitic Copepods Of Chinook, Oncorhynchus Tshawytscha (Walbaum), And Coho, Oncorhynchus Kisutch (Walbaum), Salmon Of Lake Michigan, Joseph K. Buttner
Parasitic Copepods Of Chinook, Oncorhynchus Tshawytscha (Walbaum), And Coho, Oncorhynchus Kisutch (Walbaum), Salmon Of Lake Michigan, Joseph K. Buttner
Master's Theses
No abstract provided.
The Teratogenic Potential Of Sodium Dodecylbenzene Sulfonate Upon Icr Cd-1 Strain Of Mice, Raymond M. David
The Teratogenic Potential Of Sodium Dodecylbenzene Sulfonate Upon Icr Cd-1 Strain Of Mice, Raymond M. David
Master's Theses
No abstract provided.
Cuticular Amino Acids In Dirofilaria Immitis, Bonnie Anne Ozuk
Cuticular Amino Acids In Dirofilaria Immitis, Bonnie Anne Ozuk
Master's Theses
No abstract provided.
Discharge Responses Of The Nematocysts Of The Stinging Nettle Chrysaora Quinquecirrha To External Stimuli, Christa Merz Hubbard
Discharge Responses Of The Nematocysts Of The Stinging Nettle Chrysaora Quinquecirrha To External Stimuli, Christa Merz Hubbard
Master's Theses
Chrysaora quinquecirrha nematocysts and isolated in suspension were systematically exposed to a wide range of chemical and mechanical stimuli to determine which ones would initiate discharge.
Nematocysts in situ were found to be highly responsive to stimuli and showed well-marked, immediate discharge when treated with acid, base and electrical stimuli. Slight discharge occurred with salt solutions, beef extract, beef extract and contact, human hair and change in temperature.
Discharge increased with the concentration of the reagent or the strength of the mechanical stimuli. A significant increase in discharge occurred in isolated nematocysts treated with HCl, acetic acid and sodium hydroxide. …
The Effects Of The Toxins Of Lophopodella Carteri (Ectoprocta) On The Blood Gas Properties Of The Bluegill Lepomis Macrochirus, Robert Allen May
The Effects Of The Toxins Of Lophopodella Carteri (Ectoprocta) On The Blood Gas Properties Of The Bluegill Lepomis Macrochirus, Robert Allen May
Master's Theses
Lepomis macrochirus (bluegill) were exposed, in small containers, to homogenates of Lophopodella carteri, an ectoproct that contains substances toxic to gilled vertebrates. Blood pH, pco2, and po2 were determined with a blood gas analyzer. Blood carbonic anhydrase activity was measured manometrically.
The ectoproct toxins caused significant decreases in blood pH and po2 and a significant increase in blood pco2 and carbonic anhydrase activity. It is proposed that these changes in blood properties were initiated by a film of mucus covering the gill epithelium. The secretion of mucus is thought to be a response to irritation …
A Comparative Study Of Fish Populations In The Vicinity Of A Thermal Discharge In The James River, Virginia, Judson Wayne White
A Comparative Study Of Fish Populations In The Vicinity Of A Thermal Discharge In The James River, Virginia, Judson Wayne White
Master's Theses
The size, species composition and structure of fish populations in a six mi stretch of the James River in the Piedmont Province of Virginia were analyzed. Twenty collections were made by electrofishing from October 1972 through September 1973 from both the north side of the river, which received a thermal discharge from a power station, and the south side where temperatures were ambient. Parameters investigated were number of species, total number of individuals and the Shannon-Wiener and evenness indices of species diversity. Significant differences in seasonal patterns were found between the communities in the thermal discharge and those on the …
In Vitro Effects Of Prolactin, Cortisol, Aldosterone, And Cyclic Amp On Branchial Na+, K+ - Activated Atpase Of The Killifish, Fundulus Heteroclitus, Stephen Burke Kerby
In Vitro Effects Of Prolactin, Cortisol, Aldosterone, And Cyclic Amp On Branchial Na+, K+ - Activated Atpase Of The Killifish, Fundulus Heteroclitus, Stephen Burke Kerby
Master's Theses
In vitro effects of prolactin, cortisol, aldosterone, and cyclic adenosine monophosphate were studied on branchial Na+, K+ - activated ATPase of freshwater adapted killifish, Fundulus heteroclitus. Decreases in ATPase activity were found after treatment with prolactin and aldosterone. Cyclic AMP caused an increase in ATPase activity. The action of cortisol on this enzyme was not clear.A dose - response relationship was found only for cyclic AMP .It is proposed that cyclic AMP may be involved in the adaptation of F. heteroclitus to seawater.
Ketoaldehydes And Glyoxalase Type Enzymes In The Life Cycle Of Panagrellus Silusiae, Caroline Gardiner
Ketoaldehydes And Glyoxalase Type Enzymes In The Life Cycle Of Panagrellus Silusiae, Caroline Gardiner
Master's Theses
No abstract provided.
Regeneration In Zebrafish, Brachydanio Rerio, Gabriel J. Ekandem
Regeneration In Zebrafish, Brachydanio Rerio, Gabriel J. Ekandem
Master's Theses
No abstract provided.
Changes In The (Na+ K+) - Dependent Atpase Activity In Gills Of The Euryhaline Teleost, Fundulus Heteroclitus, Upon Adaptation To Freshwater And Salt Water As Determined By Specific Activities And 3h - Ouabain Binding Sites, Mary Elizabeth Gilman
Master's Theses
Previous attempts to measure the (Na++K+) - dependent ATPase in gills of euryhaline teleosts have yielded controversial results. In this study both the (Na++K+) - dependent ATPase activity and the number of JH - ouabain binding sites, representing the number of ATPase molecules, were measured in gill tissue preparations of the killifish, Fundulus heteroclitus. The (Na++K+) dependent ATPase activity and ouabain binding sites were greater in gills of fish fully adapted to freshwater than in those adapted to salinities of 17 ppt or 24 ppt. On the other …
Predicting Primary Productivity In Westhampton Lake, Richmond, Virginia., Gary Newton Moore
Predicting Primary Productivity In Westhampton Lake, Richmond, Virginia., Gary Newton Moore
Master's Theses
Several predictive photosynthetic models were tested using light, temperature, nutrient, chlorophyll, and primary productivity data collected from Westhampton Lake, Richmond, Virginia from February-September, 1972. A simple linear model, the Kendall rank correlation coefficient, was used to relate photosynthesis to individual meteorological, physical, chemical, and biological factors. iii Of the parameters measured, only the daily maximum photosynthetic efficiency ((P/chl) max ) was significantly correlated with photosynthesis. Five multiple factor (non-linear) models were tested. In the best fitting model, primary productivity was a function of the maximum observed ratio of photosynthesis/chlorophyll concentration, light intensity, temperature, nutrient concentrations, and chlorophyll concentration. The Pearson …
Effects Of Temperature And Ph On The Growth And Composition Of The Sporophyte And Gametophyte Generations Of Allomyces Arbusculus Butler (1911), Lawrence Wayne Lenz
Effects Of Temperature And Ph On The Growth And Composition Of The Sporophyte And Gametophyte Generations Of Allomyces Arbusculus Butler (1911), Lawrence Wayne Lenz
Master's Theses
Pure cultures of the sporophyte and gametophyte generations of Allomyces arbusculus Butler (1911) were grown under varied conditions of temperature and pH. On solid media the gametophyte did not grow at 10 and 15 C; the sporophyte began slow growth after a long lag period at 15 C. There were no significant differences in growth between the sporophyte and gametophyte at 20 and 25 C. Increasing colony areas occurred for both generations at temperatures between 30 and 40 C, with the largest amount of growth for either generation at 35 C.
Colonies grown in broth media at various pH levels …
The Nature Of Miniature Melanocytes In Murine Epidermis, John Thomas Earnhardt
The Nature Of Miniature Melanocytes In Murine Epidermis, John Thomas Earnhardt
Master's Theses
In the epidermis of PET/Wmr mice the population of melanocytes reaches a peak and begins to decline during the first postnatal week, and has disappeared within four weeks. During this period a small number of weakly DOPA reactive miniature melanocytes are seen dispersed among the generally large, highly DOPA reactive melanocytes typical of the animal. These miniature melanocytes appear early, are among the last to disappear, and their population remains relatively constant against the drastically changing population of typical melanocytes. In attempts to determine the nature of the miniature melanocytes, heterologous grafting was employed whereby the melanocytes were subjected to …
Evidence For An Ambidirectional Magnesium-Activated, Sodium-Potassium Dependent Adenosine Triphosphatase, John Dale Hempel
Evidence For An Ambidirectional Magnesium-Activated, Sodium-Potassium Dependent Adenosine Triphosphatase, John Dale Hempel
Master's Theses
Controversy exists as to whether the Na-K ATPases of euryhaline fishes are the same enzyme.This study demonstrates that the phosphorylated enzyme from gills of Fundulus heteroclitus adapted to freshwater and salt water migrate to the same position in SDS polyacrylamide gels. Similar behavior of the enzyme from both sources in different ionic media is also shown. Additionally, the possible ability or the enzyme to couple an osmoregulatory influx to an excretory efflux in freshwater fish is demonstrated. The term "ambidirectional" is proposed for this enzyme, and its place in certain membrane models is discussed.
The Effects Of Ultraviolet Irradiation On The Pigment Cells Of The Pet/Wmr Mouse Epidermis, Vaughan Henry Howard Jr.
The Effects Of Ultraviolet Irradiation On The Pigment Cells Of The Pet/Wmr Mouse Epidermis, Vaughan Henry Howard Jr.
Master's Theses
Epidermal melanocytes in mammals are known to occur in a variety of shapes, sizes, and colors. The basic melanocyte morphology is dependent upon genetics, but there are a number of environmental factors that can cause modification.
In the epidermis of PET/\vrnr mice, the population of rnelanocytes reaches a peak and begins to decline during the first post-natal week, and has disappeared within four weeks. Dispersed among the large, highly DOPA-reactive melanocytes are miniature melanocytes. These miniature melanocytes are weakly DOPA-reactive and appear early in the post-natal period. The miniature melanocyte population is relatively constant and these miniature cells are among …
Ddt Inhibition Of (Na+, K+)-Activated Atpase In Gill Tissue Of Fundulus Heteroclitus, Nancy Mccutcheon Slate
Ddt Inhibition Of (Na+, K+)-Activated Atpase In Gill Tissue Of Fundulus Heteroclitus, Nancy Mccutcheon Slate
Master's Theses
The DDT inhibition of (Na+, K+) - activated ATPase in gill preparations of the euryhaline teleost, Fundulus heteroclitus, was measured. The (Na+, K+) -activated ATPase was found to be sensitive to DDT, with 74.6% of the enzyme's specific activity inhibited by 20 ppm DDT. The (Mg++)-activated ATPase was also sensitive to inhibition bv DDT but not to the extent of the (Na+, K+) - activat ed ATPase . Due to previous work which showed that DDT antagonized valinomycin-induced K+ conductance in a synthetic membrane, the effect of K+ on DDT inhibition was examined kinetically. The Km for K+ in gill …