| ECFA, ECF-A | eosinophilic chemotactic factor of anaphylaxis |
|---|---|
| PAF-A | platelet-activating factor of anaphylaxis |
| SRF-A | slow-reacting factor-anaphylaxis |
| SRSA, SRS-A | slow-reacting substance of anaphylaxis |
| AAR | active avoidance reaction; acute articular rheumatism; antigen-antiglobulin reaction |
| passive duction | A manoeuver to determine whether a mechanical obstruction is present in the eye; with forceps grasping an eye muscle, an attempt is made to passively move the eyeball in the direction of restricted rotation. Synonym: passive duction. (05 Mar 2000) |
|---|---|
| passive eruption | The apparent continued eruption of the teeth, actually the result of regression of the gingivae and crestal bone. Polymorphous light eruption, a common pruritic papular eruption appearing in a few hours and lasting up to several days on skin exposed to shortwave ultraviolet light; subepidermal oedema and deep perivascular lymphocytic infiltration is seen microscopically. Eruption sequestrum, spicule of bone overlying the central occlusal fossa of an erupting permanent molar. Serum eruption, urticaria seen in serum sickness. Surgical eruption, the uncovering of an unerupted tooth to permit its further eruption into the oral cavity by surgically removing overlying soft tissue, bone, and sometimes teeth. (05 Mar 2000) |
| passive haemagglutination | A kind of passive agglutination in which erythrocytes, usually modified by mild treatment with tannic acid or other chemicals, are used to adsorb soluble antigen onto their surface, and which then agglutinate in the presence of antiserum specific for the adsorbed antigen. Synonym: indirect haemagglutination test. (05 Mar 2000) |
| passive hyperaemia | Hyperaemia due to an obstruction in the flow of blood from the affected part, the venous radicles becoming distended. Synonym: venous hyperaemia. (05 Mar 2000) |
| passive immunity | <immunology> Immunity acquired by the transfer from another animal of antibody or sensitised lymphocytes. Passive transfer of antibody from mother to offspring is important for immune defense during the perinatal period. (18 Nov 1997) |
| passive immunization | The production of passive immunity. (05 Mar 2000) |
| passive immunotherapy | <immunology> A process in which individuals with advanced disease (who have low levels of HIV antibody production) are infused with plasma rich in HIV antibodies or an immunoglobulin concentrate (HIV Ig) from such plasma. The plasma is obtained from asymptomatic HIV-positive individuals with high levels of HIV antibodies. (09 Oct 1997) |
| passive incontinence | Dribbling of urine by reason of inability of the bladder to empty itself and of consequent overdistention. See: overflow incontinence. (05 Mar 2000) |
| passive learning | Learning without a direct attempt. Synonym: passive learning. (05 Mar 2000) |
| passive length-tension curve | The relationship between passive tension and preload (rest length) for a muscle at rest. (05 Mar 2000) |
| passive medium | A medium that produces no change in the specimens placed in it. (05 Mar 2000) |
| passive movement | Movement imparted to an organism or any of its parts by external agency; movement of any joint effected by the hand of another person, or by mechanical means, without participation of the subject himself. (05 Mar 2000) |
| passive prophylaxis | Use of an antiserum from another person or animal to provide temporary (a week to 10 days) protection against a specific infectious or toxic agent. (05 Mar 2000) |
| passive transference | The passage of an immunity or allergic susceptibility by the injection of serum of an animal or individual who has acquired an active immunity to the disease. (05 Mar 2000) |
| passive transport | <biochemistry, physiology> The movement of a substance, usually across a plasma membrane, by a mechanism that does not require metabolic energy. See: active transport, transport protein, facilitated diffusion, ion channels. (18 Nov 1997) |