摘要:In 1961 the WHO Expert Committee on Biological Standardization asked the National Institute for Medical Research, London, to collect and study material to replace the first International Standard for Serum Gonadotrophin, stocks of which were running low. This paper describes the material that was contributed, its distribution into ampoules and the international collaborative assay to compare its biological activity with that of the first International Standard. On the basis of the results obtained the material has been established as the second International Standard for Serum Gonadotrophin, with a potency of 1600 International Units per ampoule. The International Unit for Serum Gonadotrophin is thus defined as the activity contained in 0.003569 mg of the second International Standard for Serum Gonadotrophin. Full text Full text is available as a scanned copy of the original print version. Get a printable copy (PDF file) of the complete article (1.4M), or click on a page image below to browse page by page. Links to PubMed are also available for Selected References . 761 762 763 764 765 766 767 768 769 770 771 772 773