ammonium (redirected from Siwa Oasis)

ammonium /am·mo·ni·um/ (ah-mo´ne-um) the hypothetical radical, NH4, forming salts analogous to those of the alkaline metals.

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ammonium carbonate  a mixture of ammonium bicarbonate (NH4HCO3) and ammonium carbamate (NH2CO2NH4), used as a stimulant, as in smelling salts, and as an expectorant.

ammonium chloride  a systemic and urinary acidifying agent and diuretic, also used orally as an expectorant.

ammonium lactate  lactic acid neutralized with ammonium hydroxide, applied topically in the treatment of ichthyosis vulgaris and xerosis.

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am·mo·ni·um (-mn-m)

n.

The univalent radical NH₄⁺, that is derived from ammonia and that reacts as a univalent metal in forming ammonium compounds.

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ammonium (NH₄⁺),

an ion formed by the reaction of ammonia (NH₃) with a hydrogen ion (H⁺). The ammonium ion is highly soluble in water but does not pass easily through cell membranes, as does the ammonia molecule, and its rate of excretion is influenced in part by the acidity of urine. The lower the pH, the greater the proportion of ammonium ions present, assuming a constant level of ammonia production from amino acid metabolism.

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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.

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ammonium

a hypothetical radical, NH₄, forming salts analogous to those of the alkaline metals. See also ammonia.

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ammonium acetate

a weak diuretic and feed supplement.

ammonium bifluoride

wood preservative; causes diarrhea and fall in milk yield in cattle.

ammonium carbonate, ammonium chloride

saline expectorants used for the purpose of liquefying pulmonary secretions. Effectiveness has not been proven. They are sometimes used as a reflex stimulant because of the strong ammonia given off. The chloride salt is used mainly as a urinary acidifier. Excessive dosage may produce acidosis.

ammonium magnesium phosphate

see magnesium ammonium phosphate.

ammonium metavanadate

experimentally causes vanadium poisoning.

ammonium nitrate

causes nitrate poisoning.

ammonium oxalate

causes oxalate poisoning.

ammonium phosphate

a feed additive for cattle. The monobasic salt provides 27% phosphorus and 13% nitrogen, while the dibasic salt provides 23% phosphorus and 21% nitrogen.

ammonium sulfamate

used as a herbicide; cattle and deer eating treated plants may be poisoned.

ammonium sulfate

causes ammonia poisoning.

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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