Abstract
Time for the amount of radioactivity in a living organism to be reduced to half of its value existing at an earlier initial time. The amount diminishes due to two concurrent processes: radioactive decay and clearance from the system. If just the former occurs, this effective half-life is independent of initial time and is equal to the isotope’s half-life. When there is biological clearance of a substance, there is also its associated half-life.
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© 2012 Springer-Verlag Berlin Heidelberg
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Thie, J.A. (2012). E. In: Nuclear Medicine Imaging: An Encyclopedic Dictionary. Springer, Berlin, Heidelberg. https://doi.org/10.1007/978-3-642-25035-4_5
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DOI: https://doi.org/10.1007/978-3-642-25035-4_5
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