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Fishberg concentration test

[fĭsh′bərg]
n.
  1. A test of renal water conservation in which urine samples are collected after the individual has abstained from fluids overnight and the specific gravity of the urine is measured.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.