laboratory diagnostic - coagulation - Factor XI, Rosenthal, activity, citrated plasma 2ml. The plasma must be frozen within 1 hour after collection and must be sent in the frozen samples container. The factors VIII, IX, XI,XII (aPTT factors) assay requires at least 2 mL of citrated plasma frozen at -20°C. Attach the clinical data relating to the patient (major inflammatory syndrome, pregnancy, etc.) and the circumstances (bleeding, thrombosis, preoperative evaluation, etc.), Chronometric, ssso, todylaboratories®, bmn, code L16LD1567