Category: N

  • Negative study

    An investigation in which no benefit of a treatment, or no association between a risk factor and an outcome, is demonstrated; also called negative trial. Such studies may be important in disproving misconceptions about a disease, treatment, or presumed associations between risk factors and outcomes.  

  • Negative sign

    Minus sign (-) used in subtraction, to denote something that is below zero, or to indicate a lack.  

  • Negative pressure pulmonary edema

    Pulmonary edema occurring in a patient with upper airway obstruction and negative intrapleural pressures, e.g., in a child with epiglottitis.  

  • Negative crossmatch

    In organ transplantation, a lack of reaction between recipient and donor cells.  

  • Needleholder

    A forceps used to drive a needle with an attached suture into tissue.  

  • Necrophile

    One who is affected with necrophilia.  

  • Necrobiosis lipoidica diabeticorum

    A skin disease marked by necrotic atrophy of connective and elastic tissue. The lesions have a central yellowish area surrounded by a brownish border and telangiectases and usually present on the anterior surface of the legs. The disease is commonly found in people who have had diabetes mellitus for many years. Beginning as 1 to…

  • Neck conformer

    A splint, usually fabricated of thermoplastic material, that positions the neck to prevent flexion contractures due to burns of the anterior neck.  

  • Neck of the tooth

    The constricted area that connects the crown of a tooth to the root of a tooth.  

  • Neck of the mandible

    The constricted area below the articular condyle; the area of attachment for the articular capsule and the lateral pterygoid muscle.