Recent advances of high voltage electron microscopy in biology.

Recent advances in the understanding of the structure of biological material made possible by the high voltage electron microscope are reviewed by briefly summarizing some of the more important results obtained in the past few years. The examination of thick sections of selectively stained specimens has continued to be the most widely used approach and has yielded information on the three-dimensional organization of a range of organelles, including the Golgi apparatus, neurofibrils and the transverse tubular system of striated muscle. The alternative method of studying intact cells prepared by critical-point drying is becoming increasingly popular, and has already made a significant contribution in demonstrating the microtrabecular systems within the cytoplasm of cultured cells.