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Related to microparticle: Endothelial microparticles
1. A very small particle, especially one that can pass through a filter of specified fineness.
2. A vesicle, ranging in size from 5 to 100 mcm, released from the membrane of a cell into the circulation. Microparticles are immunologically unique to their cells of origin and may play a role in antigen presentation. Increased numbers of certain kinds of microparticle may be found in the circulation in vascular and thrombotic disorders.
[micro- + particle]
microparticle(mī″krō-part′ĭ-kĕl) [ micro- + particle],
1. A microscopic particle.
2. A fragment of cytoplasm and cell membrane, released into the circulation when the cell is injured.