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Full-Text Articles in Life Sciences

A Comparative Electrophoretic Study Of The Triatoma Rubida Complex (Hemiptera: Reduviidae: Triatominae), Robert R. Adams Sep 1966

A Comparative Electrophoretic Study Of The Triatoma Rubida Complex (Hemiptera: Reduviidae: Triatominae), Robert R. Adams

Loma Linda University Electronic Theses, Dissertations & Projects

A taxonomic study of the Triatoma Rubida Complex was conducted at the subspecific and hybrid levels using cellulose acetate electrophoresis to differentiate proteins in the hemolymph.

The following studies were conducted and results obtained: Laboratory-induced bleeding over a 4-week period markedly lowers the total protein of the bugs studied. Patterns obtained from chicken-fed and rabbit-fed bugs, although similar, showed some noticeable differences. Pathological-appearing bugs demonstrated protein patterns that varied greatly from the patterns obtained of normal bugs. The protein patterns obtained from hemolymph of 4th and 5th instar nymphs were quite similar, except for distance of migration. The computer was …


The Fecal Shedding Of Listeria Monocytogenes By Conventional And "Germ Free" Mice, Margaret Joyce Ramsay Sep 1966

The Fecal Shedding Of Listeria Monocytogenes By Conventional And "Germ Free" Mice, Margaret Joyce Ramsay

Loma Linda University Electronic Theses, Dissertations & Projects

A series of experiments involving Listeria monocytogenes was undertaken to study first the fecal shedding of Listeria by conventional mice challenged intraperitoneally with Listeria and second the fecal shedding and ability to survive of germ free mice with similar challenge. In addition, mites infesting Listeria infected mice were cultured for their possible contamination by Listeria.

Conventional mice were challenged intraperitoneally with a single near LD50 dose of Listeria. Fecal Listeria were detected by collecting specimens from each mouse daily for the first 4 days and every second day thereafter. The feces was held at 7°C for 14 …


Host And Prophage Modifications Of Ultraviolet Induction In Salmonella Potsdam, Bela B. Toth Sep 1966

Host And Prophage Modifications Of Ultraviolet Induction In Salmonella Potsdam, Bela B. Toth

Loma Linda University Electronic Theses, Dissertations & Projects

In induction experiments with naturally occurring and artificially lysogenic strains of S. potsdam, cells were irradiated in buffer, transferred to complete medium, and then assayed for free phage. Irradiation was followed by half hourly samples for free phage from the growing populations of irradiated cells. For an estimation of burst sizes, the irradiated cells were diluted out to a final concentration of 1 cell per ml and distributed to tubes in 0.5 ml quantities. All assays were done by the top-layer method with streptomycin incorporated in the top-layer and SP2-strr as the bacterial indicator. The non-lysogenic strain S. …


Biochemical Properties Of Salmonella Potsdam Bacteriophage P4/2, Clyde L. Roggenkamp Sep 1966

Biochemical Properties Of Salmonella Potsdam Bacteriophage P4/2, Clyde L. Roggenkamp

Loma Linda University Electronic Theses, Dissertations & Projects

Over 90% recovery of phage P4/2 was realized with differential centrifugation concentration and purification, whereas only about 16% was recovered from the aqueous two-phase polymer - Genetron - ECTEOLA-cellulose column system. Purity of preparations was greatest with the density gradient centrifugation (A260 = 2.66 and A280 = 1.80 per 1012 plaque-forming units). With the chemical system of concentration and purification followed by an ECTEOLA anion exchange run, the A260 was 6.6 and the A280 was 4.3.

Three tests were employed to determine the configuration of P4/2 DNA: (1) a formalin denaturation test, (2) a thermal …


Isolation Of A Toxic Substance From Centaurea Repens, Merton E. Sprengel Aug 1966

Isolation Of A Toxic Substance From Centaurea Repens, Merton E. Sprengel

Loma Linda University Electronic Theses, Dissertations & Projects

A poisonous steroid-type compound was isolated from Centaurea repens. After extraction with absolute ethanol, removal of the solvent, addition of 2% HCl to precipitate the pigments, and filtering, the pH was adjusted to 9 with aqueous anunonia. This solution was exhaustively extracted with chloroform, evaporated to dryness, and extracted with ethyl ether.

This fraction was chromatographed on silica-gel plates, using 10:1 1,2-dichloroethane-methanol as the developer. The band at Rf 4.2 was removed and found toxic to mice. Labored, slow, gasping respiration and frequent involuntary muscular contractions became apparent within a few minutes following the intraperitoneal injection into each animal. Death …


Molecular Taxonomy Of Triatominae, Henry D. Brodie Jun 1966

Molecular Taxonomy Of Triatominae, Henry D. Brodie

Loma Linda University Electronic Theses, Dissertations & Projects

A taxonomic study of the subfamily Triatominae was conducted to determine systematic relationships using agar gel diffusion methods in the differentiation of ova antigens and electrophoresis to differentiate hernolymph proteins.

Agar gel diffusion methods indicated that two distinctive Triatominae species from South America could be distinguished from typical North American species; it was also possible to distinguish the monotypic genus Dipetalogaster from other North American populations.

A total of 180 electrophoretic tracings of Triatominae hernolyrnph were made from 18 populations of kissing bugs. Closely related populations of the Triatoma Protracta, Triatoma Rubida, and Paratriatoma Hirsuta Complexes showed group relationships within …


Biosystematics And Life Histories Of The Peromyscus Guardia Group Of Mice And Peromyscus Eremicus (Rodentia: Cricetidae), Leonard R. Brand Jun 1966

Biosystematics And Life Histories Of The Peromyscus Guardia Group Of Mice And Peromyscus Eremicus (Rodentia: Cricetidae), Leonard R. Brand

Loma Linda University Electronic Theses, Dissertations & Projects

The purpose of this project was to investigate the taxonomic relationship and the biology of Peromyscus eremicus, and the Peromyscus guardia group of mice from islands in the Gulf of California.

Hybridization experiments were conducted between P. eremicus and P. interparietalis ryckmani. They were interfertile and produced fertile hybrids. Peromyscus guardia did not breed in the laboratory.

Body and skull measurements for P. eremicus, P. interparietalis ryckmani, and their F1 hybrids were analyzed by computing the discriminant functions and plotting a canonical scattergram. Peromyscus interparietalis ryckmani is quite distinct from P. eremicus. The hybrids were larger than either parent …


Influence Of Caloric Distribution On Weight Loss, Georgia E. Hodgkin Jun 1966

Influence Of Caloric Distribution On Weight Loss, Georgia E. Hodgkin

Loma Linda University Electronic Theses, Dissertations & Projects

The purpose of this study was to determine the effect timing of meals has on the rate of weight loss. Five hospitalized obese adults were placed on a 1200 Calorie reducing diet for approximately eight weeks.

For about a four-week period the 1200 Calories were divided into six meals per day of 200 Calories each. These same patients were given the 1200 Calories in three meals per day approximately another four-week period. With three meals per day, the calories were divided into 200 Calories for breakfast and lunch and 800 Calories for the evening meal. The former pattern represents ad …


A Growth Study On Phenylketonurics, Emma Johnson Aitken Jun 1966

A Growth Study On Phenylketonurics, Emma Johnson Aitken

Loma Linda University Electronic Theses, Dissertations & Projects

Data from forty-eight medical records of phenylketonuria children under treatment were investigated to determine if growth, as measured by stature, was normal; and to determine if the state of control or the age at beginning of treatment had an effect on growth. Mean intakes of phenylalanine, protein, and calories were obtained on the nutritional data only if the simultaneous serum phenylalanine was equal to or less than 6 milligrams per cent. These means were grouped according to the age of the children into 7 groups (0

The height at beginning of treatment and the last measured height was compared with …


A Comparative Study Of The 5- And 3-Meal Plans In Six Convalescent Hospitals In San Bernardino County, Donna J. Meek Jun 1966

A Comparative Study Of The 5- And 3-Meal Plans In Six Convalescent Hospitals In San Bernardino County, Donna J. Meek

Loma Linda University Electronic Theses, Dissertations & Projects

A study comparing the 3- and 5-meal plans of food service, as used in long-stay geriatric units in San Bernardino County, have been compared. Three homes utilizing the 5-meal plan and three utilizing the 3-meal plan, to serve as controls, were chosen. A random sample of ten patients from each home was observed for three days to find the daily average nutrients in the foods served, eaten, and wasted. Also, interviews to compare factual information and attitudes were utilized for sample patients and personnel. The nutritional data was analyzed on the computer.

The results indicated that those on the 5-meal …


An Organ Culture Technique For Maintaining The Pulp Tissue Of Intact Human Teeth, John P. Devincenzo Jun 1966

An Organ Culture Technique For Maintaining The Pulp Tissue Of Intact Human Teeth, John P. Devincenzo

Loma Linda University Electronic Theses, Dissertations & Projects

The size of explants in organ culture is limited by their ability to feed, respire, and excrete by diffusion. The perfusion procedure described in this report is not limited to a particular explant size. The test tissue was the adult human tooth.

In order to maintain the pulp tissue of the intact human tooth in organ culture, special precautions were taken to prevent internal necrosis and to allow diffusion of nutrients and waste products. Using aseptic technique, a standard tissue culture medium plus appropriate antibiotics were delivered to a glass manifold housed in an incubator with an atmosphere at 100% …