RT Journal A1 Tage-Hansen E T1 SUmmary of some clinical studies on vitamin k JF Journal of the American Medical Association JO Journal of the American Medical Association YR 1939 FD November 18 VO 113 IS 21 SP 1875 OP 1876 DO 10.1001/jama.1939.72800460001008a UL http://dx.doi.org/10.1001/jama.1939.72800460001008a AB In continuation of the work of Dam and Glavind1 I have in the past year carried out a series of investigations on patients with diseases in which lowered prothrombin might be expected. The determination of prothrombin was made by the method described by these authors. It was found to work satisfactorily. In fourteen of the cases in which lowered prothrombin (high R-values) were found, the different ways of administering vitamin K were also studied.Dam and Glavind1 reported the treatment of five cases of obstructive jaundice with K-avitaminosis by intramuscular injections of an emulsion of vitamin K in water and found it possible to restore the blood coagulation to the normal value within a week.Since then I have studied the effect of vitamin K when given perorally, intramuscularly and intravenously.For peroral use gelatin or starch capsules containing the concentrate together with desoxycholic acid were prepared. In