Abstract:
:Fission fragment tracks from uranium-stained biological preparations have been observed in the electron microscope in a study of the feasibility of their use as tracers. Virus, DNA, and tissue sections were stained with uranium, prepared for electron microscopy, irradiated in the high thermal neutron flux of a nuclear reactor, and examined without further treatment in the electron microscope. Support films of 50 to 100 A of silicon monoxide and a conventional shadow layer of chromium revealed distinct fission fragment tracks with no other discernible damage to the specimen. Virus and DNA specimens were irradiated to 3 x 10(18) n/cm(2) (thermal) and tissue sections to 3 x 10(16) n/cm(2) (thermal). About (1/4) of the calculated number of fissions left detectable tracks. It is estimated that the position of a uranium atom on a DNA fibril may be determined to 50 A, and a uranium atom in a virus preparation or tissue section to about (1/2) micron
journal_name
Biophys Jjournal_title
Biophysical journalauthors
MALMON AGdoi
10.1016/s0006-3495(64)86765-5subject
Has Abstractpub_date
1964-01-01 00:00:00pages
1-10eissn
0006-3495issn
1542-0086pii
S0006-3495(64)86765-5journal_volume
4pub_type
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journal_title:Biophysical journal
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更新日期:2006-03-15 00:00:00
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pub_type: 杂志文章
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更新日期:2001-11-01 00:00:00