ammonium

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ammonium

 [ah-mo´ne-um]
a hypothetical radical, NH4, forming salts analogous to those of the alkaline metals.
ammonium carbonate a mixture of ammonium compounds used as a liquefying expectorant in the treatment of chronic bronchitis and similar lung disorders. It is sometimes used as a reflex stimulant in “smelling salts” because of the strong ammonia odor it gives off.
ammonium chloride colorless or white crystals, with a cool, salty taste, used as an expectorant because it liquefies bronchial secretions. In the body it is changed to urea and hydrochloric acid, and thus is useful in acidifying the urine and increasing the rate of urine flow. Excessive dosage may produce acidosis.
ammonium lactate lactic acid neutralized with ammonium hydroxide, applied topically in the treatment of ichthyosis vulgaris and xerosis.
Miller-Keane Encyclopedia and Dictionary of Medicine, Nursing, and Allied Health, Seventh Edition. © 2003 by Saunders, an imprint of Elsevier, Inc. All rights reserved.

am·mo·ni·um

(ă-mō'nē-yŭm),
An ion, NH4+, formed by combining NH3 and H+ (the pKa value is 9.24); acts as a univalent metal in forming ammonium compounds.
Farlex Partner Medical Dictionary © Farlex 2012

storage lesion

Transfusion medicine The constellation of changes occurring in a unit of packed red cells during storage. See Red cell preservatives.
Storage lesions
Ammonium to 470 µmol/L–US: 800 µg/dL
Free Hb in plasma from 82 to 6580 mg/L–US: 8.2 to 658 mg/dL
K+ from 4.2 to 78.5 mmol/L–US: 4.2 to 78.5 mEq/L
ATP from 100% to 45%
2,3 DPG to < 10% of original levels–replenished within 24 hours of transfusion
Labile proteins, eg complement, fibronectin and coagulation factors ↓ to negligible
Na+ from 169 to 111 mmol/L–US: 169 to 111 mEq/L
pH from 7.6 to 6.7
Adverse physiologic effects of stored blood is negligible in the absence of a previous compromise of the Pt's–recipient's status
McGraw-Hill Concise Dictionary of Modern Medicine. © 2002 by The McGraw-Hill Companies, Inc.

am·mo·ni·um

(ă-mō'nē-ŭm)
The ion, NH4+, formed by combination of NH3 and H+; behaves as a univalent metal in forming compounds.
Medical Dictionary for the Health Professions and Nursing © Farlex 2012
References in periodicals archive ?
In numerous researches for AAEMFC, quaternary ammonium groups were used frequently as ionic conducting groups.
A balance between high ionic conductivity and low methanol permeability was created by highly concentrated quaternary ammonium groups and crosslinked structures [19, 20].
Quaternary ammonium groups have been especially investigated and extensively used as ion-exchanged cationic groups in polymeric electrolytes [7-18].
The spectra showed the following main characteristic absorption bands (in [cm.sup.-1]): 1735 (C=O) of ester bond, 1482 bending band of the quaternary ammonium groups, (-[N.sup.+](C[H.sub.3])), 1175 (C-O) of ester.
This indicates that a longer hydrocarbon chain connecting the two ammonium groups does not provide a firmer anchoring of biquats in the PE.
This effect was attributed to the ammonium groups in the organoclay, which forms Zn-sulfur-amine complex leading to improvement of properties of interests.
Thus, chemical modification of chloromethylated polysulfone by the quaternization of ammonium groups is an efficient method for increasing the hydrophilicity.