myelosuppression

suppression

 [sŭ-presh´un]

the act of holding back or checking.

1. the stopping or inhibition of something, such as a secretion, excretion, normal discharge, or other function.

2. in psychiatry, conscious inhibition of an unacceptable impulse or idea as contrasted with repression, which is unconscious.

3. in genetics, a second mutation occurring at a site different from the first mutation site and able to mask or suppress the phenotypic expression of the first mutation; the organism appears to be reverted but is in fact doubly mutant.

4. inhibition of the erythrocytic stage of Plasmodium to prevent clinical attacks of malaria; used for prophylaxis.

5. cortical inhibition of perception of objects in all or part of the visual field of one eye during binocular vision.

bone marrow suppression reduction of the cell-forming functions of bone marrow, such as by a drug or because of replacement of the marrow by a disease process. Called also myelophthisis and myelosuppression.

labor suppression in the nursing interventions classification, a nursing intervention defined as controlling uterine contractions prior to 37 weeks of gestation to prevent preterm birth. See also labor.

lactation suppression in the nursing interventions classification, a nursing intervention defined as facilitating the cessation of lactation and minimizing breast engorgement after childbirth.

overdrive suppression the suppression of intrinsic cellular automaticity by a rapid outside stimulus. In cardiology this refers to the inhibitory effect of a faster pacemaker on a slower pacemaker. The faster rate causes an accumulation of intracellular sodium, stimulating the sodium-potassium pump, which hyperpolarizes the cell so that it takes longer to reach threshold potential. This phenomenon is present in healthy His-Purkinje cells but decreases with a decrease in membrane potential and loss of fast sodium channels.

Miller-Keane Encyclopedia and Dictionary of Medicine, Nursing, and Allied Health, Seventh Edition. © 2003 by Saunders, an imprint of Elsevier, Inc. All rights reserved.

myelosuppression

Oncology The suppression–usually an undesired side effect–of normal BM activity, often the result of RT, chemotherapy, or various toxins. Cf Myelosuppressive therapy.

McGraw-Hill Concise Dictionary of Modern Medicine. © 2002 by The McGraw-Hill Companies, Inc.

my·e·lo·sup·pres·sion

(mī'ĕ-lō-sŭ-presh'ŭn)

A reduction in the ability of the bone marrow to produce blood cells: platelets, red blood cells, and white blood cells. Typically caused by cancer chemotherapy and radiation therapy. During the period of myelosuppression, patients may be at an increased risk of infection or bleeding or may experience symptoms of anemia.

[G. myelos, marrow, + L. suppressio, pressing under]

Medical Dictionary for the Health Professions and Nursing © Farlex 2012

my·e·lo·sup·pres·sion

(mī'ĕ-lō-sŭ-presh'ŭn)

A reduction in the ability of the bone marrow to produce blood cells: platelets, red blood cells, and white blood cells.

[G. myelos, marrow, + L. suppressio, pressing under]

Medical Dictionary for the Dental Professions © Farlex 2012