Results 261 to 270 of about 72,751 (304)

The purine metabolism of human erythrocytes

Biochemistry (Moscow), 2006
This review summarizes currently available information about a crucial part of erythrocyte metabolism, that is, purine nucleotide conversions and their relationships with other conversion pathways. We describe the cellular resynthesis, interconversion, and degradation of purine compounds, and also the regulatory mechanisms in the conversion pathways ...
W, Dudzinska, A J, Hlynczak, E, Skotnicka, M, Suska   +3 more
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Purine metabolism in human lymphocytes

Blut, 1979
In peripheral human blood lymphocytes the uptake and metabolism of adenine, guanine, and hypoxanthine was investigated. This was achieved by incubation of purified lymphocytes with 14C-purine bases, separation of cells from the incubation medium by a rapid filtration technique, and subsequent separation of the acid soluble material by thin-layer ...
M M, Müller, G, Pischek, O, Scheiner, H, Stemberger, G, Wiedermann   +4 more
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Purine metabolism in primitive erythrocytes

Comparative Biochemistry and Physiology Part B: Comparative Biochemistry, 1973
Abstract 1. 1. The activities of AMP kinase, GMP kinase, NDP kinase, PNPase and HGPRTase were determined in the erythrocytes of seal, eel, hagfish and dogfish. 2. 2. Erythrocytic NDP kinase activities were high and electrophoretically heterogeneous in all species examined. 3. 3.
R E, Parks, P R, Brown, Y C, Cheng, K C, Agarwal, C M, Kong, R P, Agarwal, C C, Parks   +6 more
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Metabolism and Ecology of Purine Alkaloids

Frontiers in Bioscience, 2006
In this review, the biosynthesis, catabolism, ecological significance, and modes of action of purine alkaloids particularly, caffeine, theobromine and theophylline in plants are discussed. In the biosynthesis of caffeine, progress has been made in enzymology, the amino acid sequence of the enzymes, and in the genes encoding N-methyltransferases.
Ana Luisa, Anaya, Rocio, Cruz-Ortega, George R, Waller   +2 more
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Purine metabolism in Trypanosoma cruzi

Molecular and Biochemical Parasitology, 1981
Culture forms of Trypanosoma cruzi are incapable of synthesizing purines de novo from formate, glycine, or serine and require an exogenous purine for growth. Adenine, hypoxanthine, guanine, xanthine and their respective ribonucleosides are equal in their abilities to support growth.
R L, Berens, J J, Marr, S W, LaFon, D J, Nelson   +3 more
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Enzymes of purine metabolism in cancer

Clinical Biochemistry, 1983
In cancer cells, a marked imbalance in the enzymic pattern of purine metabolism is linked with transformation and/or progression. In chemically-induced, transplantable hepatomas in rat, the specific activities of the anabolic enzymes, IMP dehydrogenase, GMP synthetase, adenylosuccinate synthetase, adenylosuccinase, AMP deaminase and ...
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Disorders of purine and pyrimidine metabolism

Molecular Genetics and Metabolism, 2005
The disorders of purine and pyrimidine metabolism are unusual in their variety of clinical presentations and in the mechanisms by which these presentations result from the fundamental mutations. In the most common of the hyperuricemic metabolic disorders, deficiency of hypoxanthine phosphoribosyl transferase, the fundamental deficiency in the activity ...
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Purine and Pyrimidine Metabolism in Leishmania

2008
Purines and pyrimidines are indispensable to all life, performing many vital functions for cells: ATP serves as the universal currency of cellular energy, cAMP and cGMP are key second messenger molecules, purine and pyrimidine nucleotides are precursors for activated forms of both carbohydrates and lipids, nucleotide derivatives of vitamins are ...
Nicola S, Carter, Phillip, Yates, Cassandra S, Arendt, Jan M, Boitz, Buddy, Ullman   +4 more
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Purine Metabolism in Rat Macrophages

1984
The association of deficiencies of purine metabolic enzymes with immunodeficiency diseases has stimulated research in purine metabolism of lymphoid cells. Up to now our knowledge about purine metabolism of other cells of the immune system, e.g., macrophages, is relatively limited.
J, Barankiewicz, A, Cohen
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Immunological Aspects of Purine Metabolism

1977
The development of our knowledge of the immune system has been reviewed and evidence presented of the need for a rapid rate of purine synthesis de novo for the proliferative events in this process. The mechanism of the inhibition of the immune system in a model of ADA deficiency has been studied intensively and considerable indirect evidence obtained ...
J E, Seegmiller, T, Watanabe, M H, Shreier, T A, Waldmann   +3 more
openaire   +2 more sources