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Platelet biology

Charles S Abrams, MD
Section Editor
Lawrence LK Leung, MD
Deputy Editor
Jennifer S Tirnauer, MD


The platelet is a circulating anucleate disc-shaped cell, responsible for initiation of the hemostatic mechanisms that repair injury to the vascular endothelium. The four major platelet functions include the following (figure 1):

Platelet adherence

Platelet activation and secretion

Platelet aggregation [1]

Interaction with coagulation factors

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Literature review current through: Dec 2017. | This topic last updated: Aug 18, 2017.
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