Contents

04 January 1985
Vol 227, Issue 4682

About The Cover

Microscopic image of a fully hydrated and live human platelet obtained by x-rays. A freshly prepared platelet suspension was exposed to a flash x-ray source of high intensity which produced a bas-relief impression on a photon-sensitive resist. The latter was examined by scanning electron microscopy. The live platelet was in a state of activation. Intracellular organelles are seen here contracted in one core of photon-dense material from which pseudopods originate. See page 63. [Photo digitizing by A. Appel and A. Stein, IBM, Yorktown Heights, New York 10598; image produced with Maxwell Laboratories Low Energy X-ray Illumination Source, San Diego, California 92123]