Author: Glossary

  • Hyperglycaemi

    Elevated plasma concentration of glucose, caused by a failure of the normal hormonal mechanisms of blood glucose control.  

  • Hypercholesterolaemia

    Abnormally high blood concentrations of cholesterol. Generally considered to be a sign of high risk for atherosclerosis and ischaemic heart disease. Hypercholesterolemia is a condition characterized by elevated cholesterol levels in the blood. This condition is believed to be linked to high levels of low-density lipoprotein (LDL) in the bloodstream. It can be caused by…

  • Hyperchlorhydria

    Excess secretion of hydrochloric acid in the stomach due to secretion of a greater volume of gastric juice rather than to a higher concentration. Excess hydrochloric acid in stomach juice. An excess of hydrochloric acid in the stomach. Excessive secretion of hydrochloric acid into the stomach by the gastric cells. An insufficient secretions is termed…

  • Hypercalcaemia, idiopathic

    Elevated plasma concentrations of calcium believed to be due to hypersensitivity of some children to vitamin D toxicity. There is excessive absorption of calcium, with loss of appetite, vomiting, constipation, flabby muscles, and deposition of calcium in the soft tissues and kidneys. It can be fatal in infants.  

  • Hyperalimentation

    Provision of unusually large amounts of energy, either intravenously (parenteral nutrition) or by nasogastric or gastrostomy tube (enteral nutrition). Infusion of life-sustaining fluids, electrolytes, and elements of nutrition intravenously or via the gastrointestinal tract. The feeding of large amounts of nutrients by mouth or intravenously to someone with serious nutritional deficiency. Early term for parenteral…

  • Hyper

    Prefix meaning above the normal range, or abnormally high. Beyond normal limits, excessive.  

  • 25-hydroxyvitamin D

    The most abundant vitamin D derivative, found mainly in blood serum (plasma), which is usually measured so as to define vitamin D status. It is the precursor of the hormone, 1,25-dihydroxyvitamin D, which is formed in the kidney, by an enzyme which is homeostatically controlled so as to liberate the appropriate amount of the hormone…

  • Hydroxyproline index

    Urinary excretion of hydroxyproline is reduced in children suffering protein energy malnutrition. The index is the ratio of urinary hydroxyproline to creatinine per kg of body weight, and is low in malnourished children. A ring-structured nonessential amino acid.  

  • Hydroxyapatite

    The calcium phosphate complex which is the main mineral of bones and teeth. The crystalline forms make up dental enamel. Calcium and phosphate salts that are responsible for the hardness of the bone matrix. The mineral complex that is deposited in the ground substance and provides hardness to bones and teeth. An inorganic compound, Ca5(PO4)3(OH),…

  • Hydrolyse (hydrolysis)

    To split a complex compound into its constituent parts by the action of water, either enzymically or catalysed by the addition of acid or alkali.