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Serological Relationships of Azotobacter Species (open access)

Serological Relationships of Azotobacter Species

In order to clarify the taxonomic problems which exist among the group azotobacter by serological method, 24 cultures of Azotobacter including 9 species were tested as antigens in Ouchterlony plates against 3 different antisera obtained from rabbits immunized with A. chroococcum ACl6, A. macrocytogenes St.M. and A. vinelandii 12837, respectively. The results showed more cross reactivity in intraspecies reactions than in interspecies ones and indicated the presence of a common immunogenic determinant. This work presents the results which suggest the effecient classification of Azotobacter by Ouchterlony comparisons of corresponding antigens in different species.
Date: December 1976
Creator: Chang, Chyan-chuu
System: The UNT Digital Library
The Effects of Diphenylhydantoin on the Lymphoreticular Tissues of the Rat (open access)

The Effects of Diphenylhydantoin on the Lymphoreticular Tissues of the Rat

A study was made of the effects of diphenylhydantoin (DPH) and the carrier solution on the spleen, lymph node, and thymus. DPH was injected i.p. at concentrations of 5 and 10 mg./100 gm. for 30 and 60 days. Hematologic effects observed were leucocytosis, neutrophilia, eosinophilia, and lymphopenia. Respiratory measurements of lymph node tissue slices were made using the oxygen electrode method. The carrier solution was found to cause a marked increase in oxygen consumption. A DPH effect on lymph tissue respiration was not observed. The carrier alone caused an atrophy of the lymph nodes and thymus, as well as an increase in the total body weight. Histological examination revealed that the 5 mg./100 gm. DPH injected for 60 days and the 10 mg./100 gm. DPH injected for 30 or 60 days produced a histiocytic cell type lymphoma, resembling Hodgkin's disease in the lymph node, thymus, and spleen in rats. The data indicated that DPH may not be a direct carcinogen, but it may interfere with the normal immune mechanism to produce the changes observed.
Date: August 1976
Creator: Gordon, Charles K.
System: The UNT Digital Library
The Effect of Ethanol on Cardiac Activity and Brain Respiration in Chick Embryos (open access)

The Effect of Ethanol on Cardiac Activity and Brain Respiration in Chick Embryos

This study concerned the effect of ethanol on cardiac activity and brain respiration in chick embryos. Ethanol dosages tested ranged from 1.0 mg to 4.0 mg/g weight. Each experiment lasted at least 150 minutes. Cardiac activity in terms of total waveform energies was integrated and printed out for plotting and analysis. The embryonic heart rates were simultaneously determined from physical graph tracings. The embryonic brain respiration was measured using a differential microrespirometer. The effect of ethanol on cardiac activity was one of slight (10 to 13), but statistically significant (p<.05) rate depression. The brain slices exhibited a marked, immediate, and irreversible decrease (39 to 89%) in oxygen consumption at both ethanol dosages. The data indicated that chick embryonic brain tissues were more susceptible to alcohol effects than cardiac tissue. Therefore, the mental abnormalities seen in the offspring of alcoholic mothers may be more cerebral in nature than cardiovascular.
Date: August 1976
Creator: Newman, James J.
System: The UNT Digital Library