Laboratory evaluation of factor VIII and factor IX.

Factor XI or plasma thromboplastin antecedent is one of the enzymes of the coagulation cascade.

Activated XII will in turn activate factor XI, which activates factor IX.

The factor xi gives a measure of the disparity between the received power levels..

Hemophilia C (Rosenthal disease) is a factor XI deficiency.

The most common etiology is due to factor XI deficiency.

Activated XII will in turn activate factor XI, which activates factor IX.

Activation of factor XII allows the activation of factor XI, which then activates factor IX.

The present invention also provides immunoglobulin composition having reduced levels of amidolytic activity, Factor XI, and/or Factor XIa, and/or ACA content.

The present invention concerns the post surgical administration of factor XIII alone or in combination with other haemostatic agents e.g. factor VIIa or factor XI for the treatment of post surgical bleeding episodes.

A blood test is required to diagnose Factor XI deficiency.

The level of Factor XI varies very little during pregnancy.

The peptides are designed by means of an equilibrium conformational model of the factor XI heavy chain.

Each International Unit (IU) of factor XI per kilogram increases the concentration of factor XI in the blood by 2.4%; the level of blood factor drops by half every two days, until it returns to the base level.

The compounds of the invention may be antagonists, or partial antagonist of factor IX and/or factor XI and thus, may be useful for inhibiting the intrinsic pathway of blood coagulation.