1 Select the Triggers tab, and then select New. 2  Set your time and frequency, and then select OK. 3  Open Windows Defender by clicking the Start button. In the search box, type Defender and then, in the list of results, click Windows Defender.  Click Tools, and then click Options.
â Platelet refractoriness is the inability to get an adequate increase in platelet count after transfusion (Arch Pathol Lab Med 2003;127:409, Haematologica 2005;90:247) â Immune causes: anti-platelet or anti-HLA antibodies after multiple exposures from transfusion, pregnancy or transplantation (Transfusion 2005;45:761)
Platelets (also called thrombocytes) are tiny oval-shaped cells made in the bone marrow. They help in the clotting process. When a blood vessel breaks, platelets gather in the area and help seal off the leak. Platelets survive only about 9 days in the bloodstream and are constantly being replaced by new cells.