(ri-dŭk′shŏn) [L. reductio, leading back] 1. Restoration to a normal position, as a fractured bone, dislocated joint, or a hernia. 2. In chemistry, a type of reaction in which a substance gains electrons and positive valence is decreased. SEE: oxidation.
breast r. Reduction mammaplasty.
closed r. of fractures The treatment of bone fractures by placing the bones in their proper position without surgery.
fat r. Elimination or limitation of greasy, fatty, or oily foods from the diet, as by substituting vegetables or legumes for cheeses and meats. Fat reduction is thought by some nutritionists to help reduce the risk of cancer.
leukocyte r. The removal of white blood cells from blood before transfusion to decrease the likelihood of transfusion reactions or infection of the recipient with viral diseases.
mindfulness-based stress r. The use of meditation and self-awareness to enhance one’s ability to cope with challenging circumstances and psychological tensions.
multifetal pregnancy r. In multiple pregnancies (as for triplets or quadruplets), the procedure for reducing the number of fetuses, to minimize the risk of maternal and fetal complications later in the pregnancy.
open r. of fractures The treatment of bone fractures by the use of surgery to place the bones in their proper position.
pathogen r. Reduction or removal of potentially infectious agents from donated blood by chemical or physical techniques.
pocket r. Surgery to eliminate deep periodontal spaces that have formed around teeth. Periodontal pockets are colonized and/or infected by numerous disease-causing bacteria. The periodontist peels away and surgically removes infected gum tissue surrounding the tooth, smooths uneven dental surfaces, and removes tartar before suturing healthy gum back onto the affected tooth.
pregnancy r. The intentional elimination of one or more fetuses carried by a woman with a multifetal pregnancy. SYN: fetal r.
risk r. 1. A decrease in the probability of an adverse outcome. 2. In biostatistics, the formula 1 – HR (the hazard ratio). 3. Any lowering of factors considered hazards for a specified disease, such as wearing a condom to lower the risk for sexually transmitted diseases, ceasing smoking to prevent lung cancer or emphysema, or lowering the intake of dietary cholesterol and fats to prevent heart disease.
salt r. Limiting the quantity of sodium chloride in the diet, usually to lower blood pressure or prevent fluid retention.
selective r. 1. In radiography, the reduction of exposed silver halide crystals to black metallic silver, creating a visible image. 2. In oncology, killing or destroying tumor cells or their products with relatively little damage to healthy cells.