Half-Life
- Half-Life: C.A.G.E.D. Is a return to the golden age of First Person Shooters. Break from captivity, conquer the facility and discover the secrets of Half-Life: C.A.G.E.D.! Featuring: Full single player campaign. Unlock-able bonus content. Music from artist Lazerhawk. Developer commentary mode.
- Return to City 17 on March 23, 2020.Set between the events of Half-Life and Half-Life 2, Half-Life: Alyx is a new full-length game built from the ground up b.
- Half-life (symbol t 1⁄2) is the time required for a quantity to reduce to half of its initial value.The term is commonly used in nuclear physics to describe how quickly unstable atoms undergo, or how long stable atoms survive, radioactive decay.
Paw paw trees for sale. Half-life T 1/2 The amount of time required for a substance to be reduced to one-half of its previous level by degradation and/or decay–radioactive half-life, by catabolism–biological half-life, or by elimination from a system–eg, half-life in serum Hematology The time that cells stay in the circulation–eg, RBCs 120 days–which ↑ after splenectomy, platelets–4-6 days, eosinophils. Sky haven download free.
Also found in: Dictionary, Thesaurus, Financial, Encyclopedia, Wikipedia.half-life
[haf´līf″
] the time required for the decay of half of a sample of particles of a radionuclide or elementary particle; see also radioactivity. Symbol t½ or T½.
Miller-Keane Encyclopedia and Dictionary of Medicine, Nursing, and Allied Health, Seventh Edition. © 2003 by Saunders, an imprint of Elsevier, Inc. All rights reserved.
half-life
(haf'līf),The period in which the radioactivity or number of atoms of a radioactive substance decreases by half; similarly applied to any substance, such as a drug in serum, whose quantity decreases exponentially with time. Compare: half-time.
half-life
(hăf′līf′, häf′-)n.1. Physics The time required for half the nuclei in a sample of a specific isotopic species to undergo radioactive decay.
2. Biologya. The time required for half the quantity of a drug or other substance deposited in a living organism to be metabolized or eliminated by normal biological processes. Also called biological half-life.
b. The time required for the radioactivity of material taken in by a living organism to be reduced to half its initial value by a combination of biological elimination processes and radioactive decay.
The American Heritage® Medical Dictionary Copyright © 2007, 2004 by Houghton Mifflin Company. Published by Houghton Mifflin Company. All rights reserved.
The amount of time required for a substance to be reduced to one-half of its previous level by degradation and/or decay (radioactive half-life), by catabolism (biological half-life), or by elimination from a system (e.g., serum half-life)Haematology The time that cells stay in the circulation—e.g., red blood cells, 120 days, which increases after splenectomy; platelets, 4–6 days; eosinophils, 3–7 hours; neutrophils, 7 hours
Immunology The time an immunoglobulin stays in the circulation: 20–25 days for IgG, 6 days for IgA, 5 days for IgM, 2–8 days for IgD, 1–5 days for IgE
Nuclear medicine The length of time required for a radioisotope to decay to one-half of the original amount having the same radioactivity; a radioisotope’s effective T1/2 is either the time of decay—physical T1/2—or the time to elimination from a biological system. See Biological half-life
Physiology The time that it takes for half of a molecule’s activity to decay
Research See Cited half-life, Citing half-life
Therapeutics The amount of time it takes for the serum concentration of a drug to fall 50%, which reflects its rate of metabolism and elimination of parent drug and metabolites in the urine and stool
Segen's Medical Dictionary. © 2012 Farlex, Inc. All rights reserved.
half-life
T1/2 The amount of time required for a substance to be reduced to one-half of its previous level by degradation and/or decay–radioactive half-life, by catabolism–biological half-life, or by elimination from a system–eg, half-life in serum Hematology The time that cells stay in the circulation–eg, RBCs 120 days–which ↑ after splenectomy, platelets–4-6 days, eosinophils–3-7 hrs, PMNs–7 hrs Immunology The time an Ig stays in the circulation: 20-25 days for IgG, 6 days for IgA, 5 days for IgM, 2-8 days for IgD, 1-5 days for IgE Therapeutics The time that a therapeutic agent remains in the circulation, which reflects its rate of metabolism and elimination of parent drug and metabolites in the urine and stool. See Effective half-life. Drug Adult Children
Gentamycin 2-3
Phenobarbital 50–150 40–70
Procainamide 2–4
Half-life 2
Theophylline 3–8 1–8
Valproic acid 8–15
McGraw-Hill Concise Dictionary of Modern Medicine. © 2002 by The McGraw-Hill Companies, Inc.
half-life
(
haf'līf) 1. The period in which the radioactivity or number of atoms of a radioactive substance decreases by half; similarly applied to any substance whose quantity decreases exponentially with time.
Compare: half-time
Compare: half-time
Half-life Definition
2. Time required for the serum concentration of a drug to decline by 50%.
Medical Dictionary for the Health Professions and Nursing © Farlex 2012
Fig. 188 Half-life . X = half-life. Note that the time taken to reach zero amount is not 2 x X.
half-life
the time required for half of the mass of a radioactive substance to disintegrate. For example, the half-life of 14C is 5,700 years.Collins Dictionary of Biology, 3rd ed. © W. G. Hale, V. A. Saunders, J. P. Margham 2005
Half-life
The time required for half of the atoms in a radioactive substance to disintegrate.
Gale Encyclopedia of Medicine. Copyright 2008 The Gale Group, Inc. All rights reserved.
half-life
(haf'līf)1. The period in which the radioactivity or number of atoms of a radioactive substance decreases by half; similarly applied to any substance whose quantity decreases exponentially with time.
Compare: half-time
Compare: half-time
2. Time required for the serum concentration of a drug to decline by 50%.
Medical Dictionary for the Dental Professions © Farlex 2012
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