activated partial thromboplastin timeelevated partial thromboplastin timethromboplastin timepartial thromboplastin time testpartial thromboplastinactivated thromboplastin timelow partial thromboplastin timepartial prothromboplastin timepart thromboplastin timepartial thromboplastin time blood testthromboplastin time testactivated partial thromboplastin