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Predicate | Object |
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rdf:type | |
lifeskim:mentions | |
pubmed:issue |
1 Pt 1
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pubmed:dateCreated |
1992-2-21
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pubmed:abstractText |
Important syntheses in living systems occur by condensation reactions of the type nA----1B (where n is the number of A molecules needed to synthesize 1 molecule of B). Quantitative relationships for estimating the rate of synthesis of B from radioactive and stable isotope tracers are compared. With radioisotope tracers, only a single quantity is detected, the amount of radioactivity in B. In contrast, isotopes of varying mass produce multiple mass isotopomers B that are detected using mass spectrometry. The analysis demonstrates that the rate of synthesis of B is identifiable from stable isotope data but not from radioisotope data. This results because the isotopomer distribution of B at any time after tracer addition is a function of only the multinomial distribution representing the synthesis of B from n molecules of A and two parameters representing the fractional fluxes of isotopically enriched molecules to the sampled compartment of B. The model considers the possibility that the sampled compartment of B may not reach isotopic steady state during the experiment. A graphical method for obtaining initial estimates of the two parameters is presented.
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pubmed:grant | |
pubmed:language |
eng
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pubmed:journal | |
pubmed:citationSubset |
IM
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pubmed:chemical | |
pubmed:status |
MEDLINE
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pubmed:month |
Jan
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pubmed:issn |
0002-9513
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pubmed:author | |
pubmed:issnType |
Print
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pubmed:volume |
262
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pubmed:owner |
NLM
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pubmed:authorsComplete |
Y
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pubmed:pagination |
E118-25
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pubmed:dateRevised |
2007-11-14
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pubmed:meshHeading |
pubmed-meshheading:1733242-Acetates,
pubmed-meshheading:1733242-Animals,
pubmed-meshheading:1733242-Drug Stability,
pubmed-meshheading:1733242-Humans,
pubmed-meshheading:1733242-Isotopes,
pubmed-meshheading:1733242-Metabolism,
pubmed-meshheading:1733242-Models, Biological,
pubmed-meshheading:1733242-Palmitates,
pubmed-meshheading:1733242-Radioisotopes
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pubmed:year |
1992
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pubmed:articleTitle |
Model equations for condensation biosynthesis using stable isotopes and radioisotopes.
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pubmed:affiliation |
Department of Physiology, George Washington University Medical Center, Washington, DC 20037.
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pubmed:publicationType |
Journal Article,
Research Support, U.S. Gov't, P.H.S.
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