Factor XI, unlike factor XII, prekallikrein (PK) and high molecular weight kininogen (HK), is
essential for normal hemostasis. This can be inferred from the observation that patients with …

Platelet activation and blood coagulation are essential for hemostasis and contribute to a
variety of other biological processes such as inflammation, complement activation and tissue …

The relationship of clinical bleeding tendency and factor XI antigen (XI: Ag) in factor XI
deficiency was studied in 78 members of 25 factor Xl-deficient kindreds. Factor XI: Ag was …

Methods The patient's plasma is re-calcified afterthe addition of different preparations
derived from normal blood. Instead of relying on the walls of glass tubes as the activating …

Factor XI deficiency has previously been observed mainly in Jews. For 34 of 36 probands
with factor XI deficiency in Israel, reliable information on ethnic background was obtained. Of …

MATERIALS AND METHODS Unless otherwise noted, all studies were performed with
blood, plasma or plasma fractions which had been collected or prepared in silicone-coated …

METHODS Unless otherwise stated all operationsinvolving blood and its components were
carried out at room temperature (approx. 200 C) using siliconed or'Polythene'apparatus …

Plasma thromboplastin antecedent (PTA) activity was measured with a quantitative assay in
the available members of the families of eight propositi with severe PTA deficiency. PTA …

Aged solutions of tannic acid and of certain o-dihydroxyl compounds similar in structure to its
gallic acid moiety accelerated clotting. One of many compounds tested, ellagic acid (4, 4 …

The observation that blood clots much more rapidly in untreated than in paraffin-coated
glass containers established that a glass surface actively promotes clotting. The major part …