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1. the entire gaseous envelope surrounding the earth and subject to the earth's gravitational field.
2. the air or climate in a particular place. adj., atmospher´ic.
3. a unit of pressure, being that exerted by the earth's atmosphere at sea level; equal to 1.01325 × 105pascals (approximately 760 mm Hg). Abbreviated atm.
Miller-Keane Encyclopedia and Dictionary of Medicine, Nursing, and Allied Health, Seventh Edition. © 2003 by Saunders, an imprint of Elsevier, Inc. All rights reserved.
Symbol for standard atmosphere.
Farlex Partner Medical Dictionary © Farlex 2012
ATMAtaxia telangiectasia mutated. A checkpoint kinase which transduces genomic stress signals to stop cell cycle progression and promote DNA repair, acting via p53, a tumour suppressor protein. Its cognate gene, ATM (see below), is mutated in ataxia telangiectasia, a rare neurodegenerative disease characterised by ataxia telangiectasias, increased chromosome fragility when exposed to ionising radiation and predisposition to lymphomas.
A gene on chromosome 11q22-q23, which encodes a PI3/PI4 cell-cycle checkpoint kinase that phosphorylates, thereby regulating a broad range of downstream proteins—e.g., tumor suppressor proteins p53 and BRCA1, checkpoint kinase CHK2, checkpoint proteins RAD17 and RAD9, and DNA repair protein NBS1.
Segen's Medical Dictionary. © 2012 Farlex, Inc. All rights reserved.
Abbreviation for standard atmosphere.
Medical Dictionary for the Health Professions and Nursing © Farlex 2012