fluid ounce

ounce

 (oz) [owns]

1. in the apothecaries' system, a unit of weight equal to ¹⁄₁₂ of a pound or 480 grains (31.103 grams); symbol ℥. See also Table of Weights and Measures in the Appendix.

2. in the avoirdupois system, a unit of weight equal to ¹⁄₁₆pound (28.3495 grams).

fluid ounce in the apothecaries' system, a unit of liquid measure equal to 8 fluid drams (29.57 ml). See also Table of Weights and Measures in the Appendix.

a unit of capacity (liquid measure) of the apothecaries' system. In the United States, it is 8 fluid drams, one sixteenth of a pint, or the equivalent of 29.57 mL. In Great Britain, it is an imperial ounce and is 8 (imperial) fluid drams but is one twentieth of an (imperial) pint, or 28.41 mL. See also Table of Weights and Measures in the Appendix.

fluid ounce (fl. oz.)

a measure of liquid volume in the apothecaries' system, which is equal to 8 fluid drams or 29 mL, 480 minims, ¹⁄₂₀ imperial pint, or the volume occupied by 437.5 grains of distilled water at a temperature of 16.7° C. See also apothecaries' measure, metric system.

fluid

1. a liquid or gas; any liquid of the body.

2. composed of molecules which freely change their relative positions without separation of the mass.

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allantoic fluid

the fluid contained within the allantois.

amniotic fluid

the fluid within the amnion that bathes the developing fetus and protects it from mechanical injury.

ascitic fluid

see ascites.

fluid balance

a state in which the volume of body water and its solutes (electrolytes and nonelectrolytes) are within normal limits and there is normal distribution of fluids within the intracellular and extracellular compartments. The total volume of body fluids should be about 60% of the body weight, and it should be distributed so that one-third is extracellular fluid and two-thirds intracellular fluid. Although this distribution remains constant in a healthy animal, there is continuous movement of fluid into and out of the various compartments. See also dehydration, water intoxication.

body f's

the fluids within the body, composed of water, electrolytes and nonelectrolytes. The volume and distribution of body fluids vary with age, sex and amount of adipose tissue. Throughout life there is a slow decline in the volume of body fluids; obesity decreases the relative amount of water in the body.

Although the body fluids are continuously in motion, moving in and out of the cells, tissue spaces and vascular system, physiologists consider them to be 'compartmentalized'. Fluid within the cell membranes is called intracellular fluid and comprises about two-thirds of the total body fluids. The remaining one-third is outside the cell and is called extracellular fluid. The extracellular fluid can be further divided into tissue fluid (interstitial fluid), which is found in the spaces between the blood vessels and surrounding cells, and intravascular fluid, which is the fluid component of blood.

The maintenance of a proper balance between the intracellular and extracellular fluid volumes is essential to health. In patients with heart failure and renal failure the balance becomes upset, producing either localized or generalized edema. Excessive fluid loss produces fluid volume deficit causing cellular dehydration and impaired cellular function.

Bouin's fluid

a histological fixative.

cerebrospinal fluid

the fluid contained within the ventricles of the brain, the subarachnoid space, and the central canal of the spinal cord. See also cerebrospinal fluid.

fluid dram

see fluid dram.

fluid extract

a liquid preparation of a vegetable drug, containing alcohol as a solvent or preservative, or both, of such strength that each milliliter contains the therapeutic constituents of 1 gram of the standard drug it represents.

fetal fluid

allantoic plus amniotic fluids.

interstitial fluid

the extracellular fluid bathing the cells in most tissues, excluding the fluid within the lymph and blood vessels.

isotonic fluid

having the same tonicity or osmotic pressure as blood.

lacrimal fluid

aqueous fluid secreted by the lacrimal glands; called also tears.

fluid line

in radiographs, the interface between fluid and gas, as in the gastrointestinal tract, will show as a straight line.

fluid loss

by vomiting, diarrhea, polyuria, water deprivation. See dehydration.

fluid mosaic model

the modern concept of the structure of a biological membrane developed by S.J. Singer and G.L. Nicolson. In it the membrane consists of protein molecules partly embedded in a discontinuous bilayer of phospholipids that form the matrix of a mosaic of functional cell units.

fluid ounce

see fluid ounce.

pericardial, pleural, peritoneal fluid

normally present in amounts sufficient only to lubricate the movement of viscera within the respective cavities. Composition similar to blood serum.

fluid replacement

see fluid therapy (below).

fluid restriction

the limitation of oral fluid intake to a prescribed amount for each 24-hour period.

fluid retention

see edema.

spinal fluid

the fluid within the spinal canal.

fluid splashing sounds

audible when gas and fluid are free in a cavity, e.g. abomasum in cases of abomasal displacement; can be elicited by shaking a small animal or part of a large animal (i.e. succussion) or by simultaneous percussion and auscultation.

synovial fluid

synovia.

fluid therapy

aims to replace fluids lost by disease process or by restriction of intake, or to maintain a high rate of fluid excretion to ensure removal of toxins, or to administer therapeutic or anesthetic agents slowly over a long period. The amounts and route of administration vary with the need of the patient. Normal solutions include 5% dextrose and Ringer's solution; alkalinizing fluids include lactated Ringer's and 1.3% sodium bicarbonate; acidifying solutions include isotonic saline and 1.9% ammonium chloride.

fluid thrill

see thrill.

fluid volume deficit

an imbalance in fluid volume in which there is loss of fluid from the body not compensated for by an adequate intake of water. The major causes are: (1) insufficient fluid intake, and (2) excessive fluid loss from vomiting, diarrhea, suctioning of gastric contents, or drainage through operative wounds, burns or fistulae. Decreased volume in the intravascular compartment is called hypovolemia. Because water moves freely between the compartments, extracellular fluid deficit causes intracellular fluid deficit (cellular dehydration), which leaves the cells without adequate water to carry on normal function.

fluid volume excess

an overabundance of water in the interstitial fluid spaces or body cavities (edema) or an excess of fluid within the blood vessels (hypervolemia) and water intoxication.

Factors that contribute to the accumulation of edematous fluid are: (1) dilatation of the arteries, as occurs in the inflammatory process; (2) reduced effective osmotic pressure, as in hypoproteinemia, lymphatic obstruction and increased capillary permeability; (3) increased venous pressure, as in congestive heart failure, thrombophlebitis and cirrhosis of the liver; and (4) retention of sodium due to increased reabsorption of sodium by the renal tubules.

fluid wave

see thrill.

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ounce

1. a measure of weight in both the avoirdupois and the apothecaries' system; abbreviation oz. The ounce avoirdupois is 28.3495 g, 1/16 lb, or 437.5 gr. The apothecaries' ounce is 31.103 g, 1/12 lb, or 480 gr.; . See also Tables 4.1 and 4.2.

2. See snow leopard.

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fluid ounce

a unit of liquid measure of the apothecaries' system, being 8 fluid drams, or the equivalent of 29.57 ml.