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in publisher: "Rochester Univ., NY USA. Dept. of Radiation Biology and Biophysics"  
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Purification of phospholamban, a 22,000 dalton protein from cardiac sarcoplasmic reticulum that is specifically phosphorylated by cyclic AMP-dependent protein kinase

Description: Very low concentrations deoxycholate (DOC) were used to isolate two proteins from canine cardiac sarcoplasmic reticulum. These two proteins are phospholamban, a 22,000 dalton protein, and the Ca/sup 2 +/ + Mg/sup 2 +/-ATPase, the major protein of the sarcoplasmic reticulum, responsible for the active transport of calcium. The 22,000 dalton protein is first solubilized in a very low concentration of DOC and then subjected to column chromatography. After molecular weight sieving on a Sephadex G-7… more
Date: January 1, 1979
Creator: Bidlack, J. M. & Shamoo, A. E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Molecular mechanism by which cyclic amp regulates myocardial contractility

Description: From these experiments, it appears that the phosphorylated 22,000 dalton protein does not regulate the transport properties of the ATPase. Instead phosphorylation of the 22,000 dalton protein causes it to become buried in the membrane, transporting Ca/sup 2 +/ into the sarcoplasmic reticulum and thereby, elevating the Ca/sup 2 +/ concentration in the sarcoplasmic reticulum available for release to the myofibrils.
Date: January 1, 1979
Creator: Bidlack, J. M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Study on the induction of thyroid tumors in rats using x irradiation in conjunction with a goitrogen. [1 methyl--2 mercaptoimidazole (methimazole)]

Description: The influence of acute localized thyroid x irradiation and chronic goitrogen administration, separately or combined, on thyroid tumor formation in mature female rats was studied. In the first experiment, the radiation doses were 0, 80, 160, 320, or 640 rads, and the dosages of goitrogen were 0, 4, or 40 parts per million (ppM) of 1 methyl - 2 mercaptoimidazole (MMI). The incidence of rats with thyroid tumors in any treated group receiving 0 or 4 ppM MMI was not significantly greater than the in… more
Date: January 1, 1979
Creator: Mahler, P.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Biomembrane modeling: molecular dynamics simulation of phospholipid monolayers

Description: As a first step toward a computer model of a biomembrane-like bilayer, a dynamic, deterministric model of a phospholipid monolayer has been constructed. The model moves phospholipid-like centers of force according to an integrated law of motion in finite difference form. Forces on each phospholipid analogue are derived from the gradient of the local potential, itself the sum of Coulombic and short-range terms. The Coulombic term is approximated by use of a finite-difference form of Poisson's eq… more
Date: January 1, 1979
Creator: Thompson, T. R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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I. Use of m- and p-azidobenzamidines, 4-fluoro-3-nitro-phenylazide, and 3-azido-1,2,4-triazole as photoaffinity probes of tryptic binding site conformation. II. Analysis of tryptophan in proteins by an acidic reaction of 3-diazonium-1,2,4-triazole

Description: Meta- and para-azidobenzamidine have been prepared and evaluated as photoaffinity labels. The compounds inhibit trypsin reversibly in the dark and are competitive with substrate binding. Upon photolysis, irreversible noncompetitive inhibition is observed and is dependent upon concentration, photolysis time, and pH. Specificity of the probes is indicated by experiments in which p-tosyl-L-arginine methyl ester, a trypsin substrate, is used to protect against photoinactivation.
Date: January 1, 1979
Creator: DeTraglia, M.C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Developmental changes in mouse: mercury retention, metabolism, and excretion after methylmercuric chloride administration

Description: The developmental change in Hg retention after MeHgCl administration has been characterized in terms of timing, dosage effects, tissue distribution, routes of Hg excretion, and form of Hg excreted. Age-dependent changes in MeHg demethylation and fecal Hg excretion have been observed. These developmental changes in distribution and excretion affect MeHg risk assessment, and provide insights into possible mechanisms of MeHg metabolism and excretion.
Date: January 1, 1979
Creator: Landry, T.D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Behavioral procedure and 60 Hertz exposure system for determining field detection by rats

Description: A new system has been constructed to determine the threshold for detecting 60 Hertz electric fields by the rat. A variant of the Method of Constant Stimuli, which has been studied intensively by other investigators for determining the thresholds of animals to a variety of stimuli, will be used in the present study. The present report describes significant features of both the exposure system and behavioral paradigm designed to study the sensitivity of the rat to 60 Hertz electric fields.
Date: January 1, 1979
Creator: Stern, S.; Laties, V. G.; Stancampiano, C.; Inglis, G. B.; Carstensen, E.; Michaelson, S. M. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Microsomal lipid peroxidation as a mechanism of cellular damage. [Dissertation]

Description: The NADPH/iron-dependent peroxidation of lipids in rat liver microsomes was found to be dependent on the presence of free ferrous ion and maintains iron in the reduced Fe/sup 2 +/ state. Chelation of iron by EDTA inhibited peroxidation. Addition of iron, after preincubation of microsomes in the absence of iron, did not enhance the rate of peroxidation suggesting that iron acts by initiating peroxidative decomposition of membrane lipids rather than by catalyzing the breakdown of pre-formed hydro… more
Date: January 1, 1979
Creator: Kornbrust, D.J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Microwaves affect thermoregulatory behavior in rats

Description: Rats, with their fur clipped, pressed a lever to turn on an infrared lamp while in a cold chamber. When 2450 Megahertz continuous wave microwaves were presented for 15 minutes, the rate of turning on the infrared lamp decreased as a function of the microwave power density, which ranged between 5 MW/cm/sup 2/ and 20 MW/cm/sup 2/. This result indicates that behaviorally significant levels of heating occur at exposure durations and intensities that do not produce reliable changes in either colonic… more
Date: January 1, 1979
Creator: Stern, S.; Margolin, L.; Weiss, B.; Lu, S.T. & Michaelson, S.M.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Effects of the rad52 gene on recombination in Saccharomyces cerevisiae. [Comparison of. gamma. -, uv-induced meiotic and spontaneous mitotic recombination]

Description: Effects of the rad52 mutation in Saccharomyces cerevisiae on meiotic, ..gamma..-ray-induced, uv-induced, and spontaneous mitotic recombination were studied. The rad52/rad52 diploids undergo premeiotic DNA synthesis; sporulation occurs but inviable spores are produced. Intra- and intergenic recombination during meiosis were examined in cells transferred from sporulation medium to vegetative medium at different time intervals. No intragenic recombination was observed at the hisl-1/hisl-315 and tr… more
Date: January 1, 1979
Creator: Prakash, Satya; Prakash, Louise; Burke, William & Montelone, Beth A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Absorption, distribution and excretion of inhaled hydrogen fluoride in the rat

Description: Rats were subjected to whole body HF exposure for 6 hrs or to nose-only HF exposure for 1 hr. Total and/or ionic fluoride concentrations in selected tissues were determined at various times following exposure. In rats sacrificed 6 hrs after whole body exposure, dose-dependent increases in lung, plasma, and kidney total and ionic fluoride concentration occurred. Rats excreted more fluoride in the urine after whole body exposure than could be explained by the amount of HF inhaled. Considerable ev… more
Date: January 1, 1979
Creator: Morris, J. B.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Renal effects of inhaled carbon tetrachloride and the influence of inhaled isopropanol: a comparison with the hepatic effects

Description: These experiments suggest that direct interaction of CC1/sub 4/ in the kidney leading to a toxic response via the peroxidative mechanism proposed for its hepatotoxicity probably does not occur in rats and mice. Although the kidney does contain lipid peroxidizable in vitro, renal metabolism of CC1/sub 4/ initiating membrane lipid peroxidation as monitored by loss G-6-Pase activity cannot be detected in vivo following exposures which cause severe peroxidation in liver. Like liver, kidney tissue c… more
Date: January 1, 1979
Creator: Henry, Ellen C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Metabolic and physical scaling in microwave/radiofrequency bioeffects studies

Description: Research on the biological effects of microwaves is primarily related to the problem of hazard assessment for exposure of man. To reach an objective, scientifically valid solution to the hazard assessment problem, two complex, integrative tasks must be systematically accomplished. One of these is the determination of the absorbed energy required to cause deleterious changes in body functions of experimental animals; this requires a quantitative evaluation and comparison of the many experiments … more
Date: January 1, 1979
Creator: Michaelson, Sol M. & Lu, Shin-Tsu
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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