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Articles 8281 - 8310 of 8425
Full-Text Articles in Microbiology
Peptidoglycan Differences In Strains Of Bacillus Cereus Constitutive And Inducible For Penicillinase Production, Kenneth W. Nickerson, Richard A. Day
Peptidoglycan Differences In Strains Of Bacillus Cereus Constitutive And Inducible For Penicillinase Production, Kenneth W. Nickerson, Richard A. Day
Papers in Microbiology
Strains of Bacillus cereus differing in penicillinase production were shown to possess cell walls of differing muramic acid contents.
Sturt Pea Hosts Collar Rot Fungus, M D. Marcley
Sturt Pea Hosts Collar Rot Fungus, M D. Marcley
Journal of the Department of Agriculture, Western Australia, Series 4
Evidence that Western Australia's Sturt Pea can be attacked by collar rot fungus suggests a reason for the occurrence of collar rot in places where the fungus should not survive.
At Carnarvon for instance, in spite of the hot, dry conditions, the collar rot fungus has been found on eggplants and Tuart trees.
Micronutrients And Biological Patterns In Lake Mead, Hasan K. Qashu, Lorne G. Everett, J. S. Carlson, Bureau Of Reclamation
Micronutrients And Biological Patterns In Lake Mead, Hasan K. Qashu, Lorne G. Everett, J. S. Carlson, Bureau Of Reclamation
Publications (WR)
Progressive increases in concentration of dissolved solids in the Colorado River water from Lake Powell to Imperial Dam seem to alter plankton dynamics and biological productivity of the river. Also, changes in biological productivity and micronutrients concentrations occur within the same reservoir. Development of a digital simulation model to predict micronutrients concentrations and biological productivity is necessary for diagnosing changes in plankton population and effluent-carrying capacity of the system. The objectives of the study are: (1) to determine trace metal balance at different locations in Lake Mead, (2) to measure biological productivity and conduct plankton population counts at each sampling …
Facility For The Biological Treatment Of A Complex Chlorophenolic Waste - A Preliminary Report, William F. Evans
Facility For The Biological Treatment Of A Complex Chlorophenolic Waste - A Preliminary Report, William F. Evans
Journal of the Arkansas Academy of Science
The City of Jacksonville, Arkansas, is attempting to determine if aeration of a combined domestic sewage — chlorophenolic herbicide waste prior to release into conventional waste stabilization lagoons will be useful in the microbiological oxidation of chlorophenols and chlorophenoxy acids.
The Nature Of Salmonella Phage P3 Modification And Restriction By Growth In Escherichia Coli, Clark A. Pearson
The Nature Of Salmonella Phage P3 Modification And Restriction By Growth In Escherichia Coli, Clark A. Pearson
Loma Linda University Electronic Theses, Dissertations & Projects
The Salmonella potsdam group B bacteriophage P3, which grows in the rough variant strain of S. potsdam (SP2-R) and E. coli KCS11, KW117, and C+/L with similar efficiencies, was restricted by SP2-R after a passage though E. coli. The entrance of restricted E. coli-grown phage DNA into nonpermissive SP2-R cells was confirmed by the finding that after adsorption of restricted 32P-labeled P3-C1·C+/L to SP2-R and removal of the adsorbed phage heads from cells, 80.3% of the labeled DNA activity sedimented with the cells. Thus restricted P3 DNA …
Antigenic Relationships In Seven Strains Of Tetrahymena, W.E. Engelhard, B.W. Mccashland
Antigenic Relationships In Seven Strains Of Tetrahymena, W.E. Engelhard, B.W. Mccashland
Papers in Microbiology
Tetrahymena, along with other genera of the family Frontoniidae, have been the subject of many scientific investigations concerning problems in protozoan physiology. Unfortunately in many instances, difficulty arises when attempting to identify properly the form that was used in the particular study. Until rather recently, relatively little had been accomplished by way of a comprehensive study of the interrelated genera, and of these very few have dealt with taxonomic problems serologically.
Lysis Of The Rhizobiaceae, Craig Richard Baumrucker
Lysis Of The Rhizobiaceae, Craig Richard Baumrucker
Masters Theses
The following members of the Rhizobiaceae were tested for their lytic response to various treatments: Agrobacterium tumefaciens, Chromobacterium violaceum, Rhizobium phaseoli, Rhizobium trifolii, Rhizobium lupini, and Rhizobium japonicum. Lysis was observed in spent growth media and as a function of saline concentration, pH, buffer composition, disodium (ethylenedinitrilo) tetraacetate (EDTA) concentration, and lysozyme.
Cells were harvested by centrifugation, washed, and resuspended in various treatment solutions. The lytic response was followed spectrophotometrically.
The different responses of the six cultures was applied to a summation of reclassification proposals evolved through modern taxonomic techniques such as DNA homology …
The Lichen Flora Of Rocky Branch Nature Preserve, Clark County, Illinois, James E. Wiedman
The Lichen Flora Of Rocky Branch Nature Preserve, Clark County, Illinois, James E. Wiedman
Masters Theses
No abstract provided.
Characterization Of Deoxyribonucleic Acid From Actinomycetes, Lynn William Enquist
Characterization Of Deoxyribonucleic Acid From Actinomycetes, Lynn William Enquist
Theses and Dissertations
Deoxyribonucleic acid (DNA) analyses were used to assess on a molecular level, the relationships among representatives of the genera Streptomyces, Nocardia and Mycobacterium. The methods developed in this study have been used for routine analysis of DNA from a large number of actinomycetes and have given reliable and reproducible data.
DNA isolated from various actinomycetes was characterized by buoyant density determinations in CsCl from which the mole fraction guanine plus cytosine (GC) content was calculated. All the streptomycete DNA preparations studied had buoyant densities in the range of 1.7287 to 1.7312 g cm-3 which corresponded to GC compositions of …
The Effect Of Immune Igm And Igg On The Infectivity Of Trichinella Spiralis In Mice, Clare K. Kwan
The Effect Of Immune Igm And Igg On The Infectivity Of Trichinella Spiralis In Mice, Clare K. Kwan
Loma Linda University Electronic Theses, Dissertations & Projects
[Abstract Not Included]
Infectivity And Development Of Trichinella Spiralis In Germ-Free, Monocontaminated And Conventional Mice, Daulat Sitanggang
Infectivity And Development Of Trichinella Spiralis In Germ-Free, Monocontaminated And Conventional Mice, Daulat Sitanggang
Loma Linda University Electronic Theses, Dissertations & Projects
The purpose of the experiment was to compare the development of Trichinella spiralis in germ-free, Lactobacillus casei monocontaminated, Escherichia coli monocontaminated and conventional mice. The criteria used in the experiments were the recovery of adults and larvae of T. spiralis after 72 hours and one month post-infection, respectively. which gave an indication of the effects of no bacteria or only a certain, single species of bacterium on the development of this nematode in mice.
Germ-free T. spiralis larvae were obtained by washing them several times with sterile normal saline, and treatment with antibiotics. The gavaging procedure was done without anesthetization …
Lactic Dehydrogenase Isozyme Isolation By Disc Electrophoresis In Eight Species Of Fringillid Birds, Michael Edwin Darling
Lactic Dehydrogenase Isozyme Isolation By Disc Electrophoresis In Eight Species Of Fringillid Birds, Michael Edwin Darling
Dissertations and Theses
Disc electrophoresis of tissue homogenates from eight species of fringillid birds showed five forms of lactic dehydrogenase. The relative amounts of isozymes were characteristic for each species. This paper classifies some members of the families Fringillidae and Carduelidae in terms of lactic dehydrogenase isozymes and compares the results to other methods of classification.
Immune Blocking Of Fluorescent Antibody Staining Of Streptococcus Group A Compared With Anti-Streptolysin O, George K. Peck
Immune Blocking Of Fluorescent Antibody Staining Of Streptococcus Group A Compared With Anti-Streptolysin O, George K. Peck
Loma Linda University Electronic Theses, Dissertations & Projects
The fluorescent antibody blocking antibody (FABA) test has been discribed and compared with the conventional antistreptolysin 0 antibody (ASOA) test in the detection of Streptococcus pyogenes group A antibodies in sera samples.
A slide inhibition test was used to detect the presence of FABA in the following manner; (a) fix group A streptococcal cells to a slide, (b) incubate these cells with the patient's serum for thirty minutes, (c) wash off serum with buffered saline and dry, (d) incubate these same cells with group A streptococcal fluorescent tagged antibody for thirty minutes, (e) wash and dry as before, and (f) …
Description And Seasonal Variation In Incidence Of A New Species Of Myxosporidian Parasite (Class Myxosporidea) Of The Bluegill Sunfish, Lepomis Macrochirus Rafineque, In Kentucky, Stephen Bayes Crider
Description And Seasonal Variation In Incidence Of A New Species Of Myxosporidian Parasite (Class Myxosporidea) Of The Bluegill Sunfish, Lepomis Macrochirus Rafineque, In Kentucky, Stephen Bayes Crider
Masters Theses & Specialist Projects
A new histozoic myxosporidian parasite (Class Mysoxporidea), Myxobolus meglitschi sp. nov., infecting young-of-the-year and yearling bluegill sunfish, Lepomis macrochirus Raf., from Shanty Hollow Lake, Warren County, Kentucky was described. Phenology was investigated from January 20 to December, 1969.
The magnitude of infection varied seasonally in bluegill. Incidence was highest in July and August (43.92) in host populations, declining, but not disappearing from September to December 20, 1969. The infection exhibited a yearly mean incidence of 22.318.
The pattern of distribution of cysts on hosts varied seasonally. During periods of low incidence cysts were confined primarily to a postanal area below …
Taxonomy And Ecology Of Fungi Imperfecti From Four Locations In Utah Lake, Utah Co., Utah, Laird Max Hartman
Taxonomy And Ecology Of Fungi Imperfecti From Four Locations In Utah Lake, Utah Co., Utah, Laird Max Hartman
Theses and Dissertations
Fungi imperfecti were cultured from water and bottom sediment samples collected at four locations of Utah Lake. These study sites included: (a) The mouth of Provo River, the largest fresh-water tributary entering Utah Lake, (b) Mud Lake, a large shallow area known for its high nitrogen content, (c) the entrance of the Spanish Fork River into the lake, a large fresh-water tributary containing wastes from industry and agricultural enterprises, (d) Jordan River, the only natural outlet of Utah Lake. One hundred and thirty-eight species of fungi imperfecti were identified. A total of 89 species were isolated from the Spanish Fork …
The Enterobacteriaceae: A Preliminary Study Of New Methods Of Identification: Rapid Biochemical Testing And Salt Tolerance, William F. Brooks Jr.
The Enterobacteriaceae: A Preliminary Study Of New Methods Of Identification: Rapid Biochemical Testing And Salt Tolerance, William F. Brooks Jr.
MUSC Theses and Dissertations
Commercially available reagent-impregnated paper strip tests and tablet substrate tests were evaluated in comparison to the standard biochemical tests using representative members of the Enterobacteriaceae. For the most part, these tests were found to be unreliable or difficult to interpret. Standard media for key biochemical tests were then modified and a new inoculation procedure developed to allow for test results after four hours incubation. Representative members of the Enterobacteriaceae were tested using the modified standard media and, where a given test was critical for the differentiation of the organisms, the rapid test results were in complete agreement with the control …
Emergency Chlorination Of Farm Water Supplies, H C. Hughes
Emergency Chlorination Of Farm Water Supplies, H C. Hughes
Journal of the Department of Agriculture, Western Australia, Series 4
TOWARDS the end of summer (and especially in a drought) the risk of water in dams, soaks, wells or tanks becoming polluted is increased.
Bore water is much less likely to be affected unless the bore is poorly sited near a farm building, such as a shearing or milking shed, a pig pen, or a septic tank system.
Studies On The Nutritional Aspects Of Tubificid Worms, Thomas Nelson Seng
Studies On The Nutritional Aspects Of Tubificid Worms, Thomas Nelson Seng
Masters Theses
No abstract provided.
The Effectiveness Of Camphorated Paramonochlorophenol, Metacresyl Acetate, And Prednisolone In Combination As An Antimicrobial Agent, Maurice Cutler
The Effectiveness Of Camphorated Paramonochlorophenol, Metacresyl Acetate, And Prednisolone In Combination As An Antimicrobial Agent, Maurice Cutler
Loma Linda University Electronic Theses, Dissertations & Projects
Post-treatment discomfort following endodontic procedures can be caused by inflammation due to injudicious use of intracanal medicaments. Camphorated paramonochlorophenol, metacresyl acetate, and prednisolone in combination is advocated to reduce the inflammatory potential of the germicide and thus reduce the occurrence of post-operative pain. It is imperative that a medicament retain antimicrobial activity while reducing inflammatory potential.
This investigation was undertaken toward determining on an in vitro quantitative bactericidal versus bacteriostatic basis by use of the broth dilution test tube method whether camphorated paramonochlorophenol, metacresyl acetate, and prednisolone in combination retains antimicrobial activity comparable to selected other commonly used nonspecific germicides. …
The Effect Of Gamma Irradiation On Growth Of Seven Strains Of Trypanosoma Avium, Roy Wesley Leid Jr.
The Effect Of Gamma Irradiation On Growth Of Seven Strains Of Trypanosoma Avium, Roy Wesley Leid Jr.
All Master's Theses
The prime motivating factor in the present study was the desire to show significant differences in radio-sensitivities within six strains of Trypanosoma avium. A seventh strain was later added for the last two irradiation treatments. Gross morphology and differences in growth curves associated with varying temperatures suggested that the strains being cultured were not the same. With these differences in mind, the strains were subjected to different dosage levels of gamma irradiation.
The Comparative Morphology Of The Female Gonads Of Two Members Of The Nematode Order Tylenchida, Owen G. Coker
The Comparative Morphology Of The Female Gonads Of Two Members Of The Nematode Order Tylenchida, Owen G. Coker
Masters Theses
No abstract provided.
Ultrastructural Investigations Of Tilletia Caries Teliospores, James Vincent Allen
Ultrastructural Investigations Of Tilletia Caries Teliospores, James Vincent Allen
Theses and Dissertations
The purpose of this study was to investigate the ultrastructure of Tilletia caries teliospores. Specimens were prepared for viewing in the electron microscope by freeze-etching and thin-sectioning techniques. Thin-sectioning techniques gave excellent results with the teliospore walls and the lipid bodies within the teliospore but failed to adequately fix the membranes and internal organelle systems. Micrographs of Tilletia caries teliospores prepared using thin-sectioning show three major wall layers and two partition wall layers and abundant lipid bodies. The freeze-etch method of spore preparation proved superior to the thin-sectioning used in this study to reveal the internal organelle systems of the …
Surface Characteristics Of Conidia From Monosporous Cultures Of Penicillium Digitatum And Aspergillus Nidulans Var. Echinulatus, Raymond Kunito Fuji
Surface Characteristics Of Conidia From Monosporous Cultures Of Penicillium Digitatum And Aspergillus Nidulans Var. Echinulatus, Raymond Kunito Fuji
Theses and Dissertations
The purpose of this investigation was to evaluate the possible taxonomic significance of the "rodlet" patterns and spore wall configurations of conidia from monosporous cultures of Penicillium digitatum Saccardo and Aspergillus nidulans Eidam var. echinulatus Fennell & Raper. Freeze-etching the conidiospores from single spore isolates of these fungi revealed that spore wall patterns and configurations vary much too greatly to be of taxonomic importance on the strain and subspecies level. Environmental factors and genetic influences are discussed as possible mechanisms causing the variations of the spore wall configurations. A membrane-like structure that covers the "rodlet" patterns and which hinders spore …
The Identification Of A Germination Factor For Basidiospores Of Psilocybe Mutans, Neal K. Van Alfen
The Identification Of A Germination Factor For Basidiospores Of Psilocybe Mutans, Neal K. Van Alfen
Theses and Dissertations
Basidiospores of the Basidiomycete Psilocybe mutans have been found to germinate only in the presence of water extracts of animal dung. The chemical nature of the factor present in the dung that induces germination is not known, nor has it ever been isolated· Experiments showed that extracts of bile salts cause the basidiospores to germinate, indicating that since bile salts are found in dung, they may be the factor which stimulates the spores to germinate. Investigations of the properties of the factor in dung show that the factor has solubility properties that are similar to those of the bile acids. …
The Intestinal Flora Of Triatoma Protracta Protracta (Uhler) (Hemiptera: Reduviidae) Including New Bacterial Isolation Techniques, Stephen A. Nyirady
The Intestinal Flora Of Triatoma Protracta Protracta (Uhler) (Hemiptera: Reduviidae) Including New Bacterial Isolation Techniques, Stephen A. Nyirady
Loma Linda University Electronic Theses, Dissertations & Projects
A bacteriological procedure for the removal of the intestinal flora of Triatominae is described. Immersion of Triatoma protracta adults and fifth instar nymphs in 5% aqueous formaldehyde for three hours was sufficient to free the integument of these insects of viable bacteria without penetration into the alimentary tract.
Twenty-two adults and 17 fifth instar nymphs of Triatoma protracta protracta were collected from Neotoma lodges in southern California. Eleven of the 17 nymphs molted into adults in the laboratory. With the use of a 2% peracetic acid sterilized custom built plastic germ-free isolator the Triatoma were dissected and various sections of …
A Comparative Survey Of Soil Microfungi From Three Vegetation Types In Cedar Valley, Utah, Brent T. Wahlquist
A Comparative Survey Of Soil Microfungi From Three Vegetation Types In Cedar Valley, Utah, Brent T. Wahlquist
Theses and Dissertations
Microfungi were isolated from soil samples by the soil plate method. Soil samples were collected at depths of 0-1", 1-4", and 4-8" both between and beneath the canopy of the dominant vegetation in stands of greasewood, sagebrush, and pinyon-juniper. Salinity, pH, and percent organic matter were measured for each soil sample. A total of 148 strains of fungi representing 141 species and 46 genera were isolated and identified from these alkaline soils, Few strains, including some Aspergilli, occurred only in the more saline greasewood soils, while many strains, including several Penicillia, occurred in both sagebrush and piny-on-juniper soils but were …
A Study Of Aquatic Fungi In Powell's Slough, Chao-Chih Hsiao
A Study Of Aquatic Fungi In Powell's Slough, Chao-Chih Hsiao
Theses and Dissertations
Aquatic fungi in-Powell's Slough were.studied in 1967 & 1968. Collections were made and water temperature, oxygen content & pH values were measured at weekly intervals. For collections, wire baskets containing substrata were submerged in water for one month. After collecting, substrata were brought to the laboratory. Identification was based on the keys of Sparrow, 1960. Aquatic fungi identified included seven orders, nine families, fifteen genera, and thirty species, from thirty-three collections of fifteen types of substrata. The substrata used in this study were: (i) fruits: apples, rose hips, plums, pears, haws; (ii) twigs: poplar, weeping willow, river birch, weeping white …
Transferable Drug Resistance Among Enterobacteriaceae Isolated From Human Urinary Tract Infections, Donna G. Sieckmann, Norman D. Reed, Carl E. Georgi
Transferable Drug Resistance Among Enterobacteriaceae Isolated From Human Urinary Tract Infections, Donna G. Sieckmann, Norman D. Reed, Carl E. Georgi
Papers in Microbiology
Fifteen sulfonamide-resistant cultures isolated from urinary tract infections in eastern Nebraska were screened for transferable drug resistance by three methods. Seven of the 15 resistant cultures could transfer resistance of varying levels to two or more chemotherapeutic agents. Transfer of drug resistance occurred without accompanying transfer of chromosomal traits and required cell to cell contact. In mixed culture, the number of drug-resistant recipients increased exponentially, reaching a plateau 2 hr after mixing. Spontaneous or artificial elimination of resistance was found to be a rare event. In addition, several drug-sensitive isolates from urinary tract infections were shown to be competent recipients …
An Epidemiological Survey Of Avian Tuberculosis In Livestock, Poultry, And Wild Birds In Rich County, Utah, Royal Thair Carver
An Epidemiological Survey Of Avian Tuberculosis In Livestock, Poultry, And Wild Birds In Rich County, Utah, Royal Thair Carver
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
A study was conducted in Rich County, Utah to determine the extent of avian tuberculosis in livestock, poultry and wild birds. Sensitivity was elicited in cattle, swine and chickens by tuberculin testing.
The Mycobacterium avium organism was obtained from tissues and specimens of cattle, swine, goats, chickens, magpies and sparrows.
Methods of eradication of avian tuberculosis and the relationship of avian tuberculosis to mammalian tuberculosis are discussed.
Can Mastitis Be Eliminated?, F C. Wilkinson
Can Mastitis Be Eliminated?, F C. Wilkinson
Journal of the Department of Agriculture, Western Australia, Series 4
Can mastitis be eliminated from a dairy herd? The results of a 12-month continuous study of four commercial herds show that it could be done.