One of the most fascinating tools at the disposal of the molecular biologist is the medical clinic. The responsibilities of those who provide health care do not stop when they give optimal care to the individual patient and train their successors adequately. They also are under the obligation to obtain maximal information from every case they treat in order to reach a better understanding of the underlying illness in order to improve therapeutic results in the next patient. Fundamental research in pathological material is therefore a medical must as well as an opportunity for scientific work. The scientist working in this field can profit from nature's unasked for experiments, which are encountered by his medical colleagues in their clinical material. There are many examples of subjects of study - for instance hemoglobins and immunoglobulins - which started in a medical context and gradually developed into a field of prime interest for the molecular biologist. The study of blood coagulation is one of the younger areas of this kind.

Inhalt
One Prothrombin.- Historical development of the prothrombin concept.- The primary structure of prothrombin, the role of vitamin K in blood coagulation and a thrombin-catalyzed 'negative feed-back' control mechanism for limiting the activation of prothrombin.- The conversion of prothrombin into thrombin.- The conversion of prothrombin to thrombin: the function of the propiece of prothrombin.- Discrepancies between the one- and two-stage prothrombin estimations in purified prothrombin preparations.- Preparation of pure prothrombin by the Cd++ method.- Staphylocoagulase.- The interaction between prothrombin and staphylocoagulase.- Inhibition of thrombin.- Two PIVKA-II.- Postribosomal synthesis of prothrombin under the influence of vitamin K.- Structural comparison of normal and dicoumarol-induced prothrombin.- Preliminary studies on human coumarin prothrombin.- Prothrombin metabolism in healthy subjects and in two patients with congenital hypoprothrombinemia.- Metabolism of PIVKA II in man.- Factors influencing prothrombin complex clotting factor synthesis in the rat.- Three Congenital Abnormalities.- A congenitally abnormal prothrombin: prothrombin Barcelona.- Prothrombin San Juan: a complex new dysprothrombinemia.- Prothrombin Padua.- Prothrombin Brussels.- Factor X Friuli.- Four PIVKA VII, IX and X.- Synthesis of factor VII.- Factor VII in patients on oral anticoagulants.- Study of human factor IX variants with an immunoadsorption technique.- Proteins induced by vitamin K antagonists (PIVKAs).- Index of subjects.