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61.
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P. F. Han S. H. Pollock H. W. Matthews J. Johnson Jr 《Cellular and molecular life sciences : CMLS》1979,35(5):586-587
Summary Treatment of turkey liver fructose-1,6-bisphosphatase with penicillin G progressively inactivated the enzyme and desensitized the enzyme toward high substrate inhibition. The treatment also led to reduced sensitivity to AMP inhibition and the loss of cooperative interaction among AMP-binding sites. These altered properties were not reversed by dialysis, but were prevented when treatment with penicillin G was performed in the presence of substrate.This work was in part supported by grant RR-8006 from the General Research Branch, Division of Research Resources, NIH (USA) and in part by Faculty Research Grant from Southern School of Pharmacy, Mercer University, Atlanta (Georgia, USA). 相似文献
63.
D. R. Johnson 《Cellular and molecular life sciences : CMLS》1977,33(4):517-518
Summary In an experiment designed to test the possible correlation between hard water and neural tube anomalies, high calcium intake was found to increase the number of exencephalic foetuses in litters from trypan blue treated mice. This is a reversal of the suggested trend in man where soft water and anencephaly may be correlated. 相似文献
64.
Purification, sequencing and synthesis of natriuretic and vasoactive rat atrial peptide 总被引:3,自引:0,他引:3
S A Atlas H D Kleinert M J Camargo A Januszewicz J E Sealey J H Laragh J W Schilling J A Lewicki L K Johnson T Maack 《Nature》1984,309(5970):717-719
Mammalian atria contain potent natriuretic and diuretic substances which exist in high- and low-molecular-weight forms and which appear to be associated with atrium-specific granules. The natriuretic effect of atrial extract is largely accountable for by its renal haemodynamic effects; atrial extracts also antagonize hormone- and non-hormone-induced contraction of the isolated rabbit aorta and isolated rat kidney vasculature. We have completely purified a low-molecular-weight natriuretic and vasoactive substance from rat atria and characterized it as a 24-amino acid peptide. Synthetic peptide, produced by solid-phase synthesis, mimics biological effects of crude atrial extract and purified peptide; its activity is enhanced by slow oxidation, suggesting a disulphide (Cys 4-Cys 20) configuration for the native peptide. If secreted into blood, this atrial natriuretic peptide (' auriculin B') could be a novel peptide hormone of considerable importance to renal and cardiovascular homeostasis. 相似文献
65.
I. T. Johnson 《Cellular and molecular life sciences : CMLS》1976,32(3):347-348
Summary The total fluid uptake of everted sacs of rat jejunum was compared in animals killed by stunning and decapitation, or anaesthetised with ether. Fluid transport was significantly higher in the tissue prepared from stunned and decapitated animals. It is suggested that etherization may have adverse effects on the physiological viability of subsequently isolated tissues. 相似文献
66.
Résumé L'hydrochlorure de méthylamphétamine, drogue qui était administrée aux rats après qu'ils aient subi une seule expérience d'entrainement, améliorerait la mémoire des animaux testés, mais cet effet se n'est produit que 7 jours après l'expérience. 相似文献
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A stress-sensitive reporter predicts longevity in isogenic populations of Caenorhabditis elegans 总被引:1,自引:0,他引:1
When both genotype and environment are held constant, 'chance' variation in the lifespan of individuals in a population is still quite large. Using isogenic populations of the nematode Caenorhabditis elegans, we show that, on the first day of adult life, chance variation in the level of induction of a green fluorescent protein (GFP) reporter coupled to a promoter from the gene hsp-16.2 predicts as much as a fourfold variation in subsequent survival. The same reporter is also a predictor of ability to withstand a subsequent lethal thermal stress. The level of induction of GFP is not heritable, and GFP expression levels in other reporter constructs are not associated with differences in longevity. HSP-16.2 itself is probably not responsible for the observed differences in survival but instead probably reflects a hidden, heterogeneous, but now quantifiable, physiological state that dictates the ability of an organism to deal with the rigors of living. 相似文献
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