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JAMA. 1938;111(24):2211. doi:10.1001/jama.1938.02790500049013.
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The recent demonstration of a head-specific and a tail-specific antigenic fraction in mammalian spermatozoa, with a third or species-specific antigen common to the heads and the tails, is of basic biologic and immunochemical interest. Separation of spermatozoa into head and tail fractions was attempted forty years ago by Miescher.1 He found that if fish spermatozoa are suspended in distilled water the relatively heavy heads can be broken off by carefully graduated centrifugation. Mammalian spermatozoa, however, cannot be broken up by this technic. Henle and his colleagues 2 of the Johnson Foundation for Medical Physics, University of Pennsylvania, have recently attempted such fragmentation by the modern technic of supersonic vibration. They found that bull, dog or rabbit spermatozoa were fairly completely broken up into head and tail fractions by exposure for seven minutes to vibrations of 9,000 cycles per second. Guinea pig spermatozoa required fifteen minutes and human spermatozoa twenty minutes


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