nation of total selenium in lyophilized human blood serum. Pure

2.5 years, requests for Se determinations have originated mainly for patients on parenteral or other nutrition, but have also included monitoring industrial exposure and investigating a deliberate overdose. In all these applica-tions, this method has proved simple and reliable, requir-ing no undue operator time and giving acceptable results within a working day. We are grateful to our colleagues Dr. Stanley S. Brown and Dr. Robin A. Braithwaite for their advice and encouragement, and t