Abstract：
:The effects of single pulses and multiple pulses of 7 MV electrons on micronuclei (MN) induction in cytokinesis-blocked human peripheral blood lymphocytes (PBLs) were investigated over a wide range of dose rates per pulse (instantaneous dose rate). PBLs were exposed to graded doses of 2, 3, 4, 6, and 8 Gy of single electron pulses of varying pulse widths at different dose rates per pulse, ranging from 1 × 10(6) Gy s(-1) to 3.2 × 10(8) Gy s(-1). Different dose rates per pulse were achieved by changing the dose per electron pulse by adjusting the beam current and pulse width. MN yields per unit absorbed dose after irradiation with single electron pulses were compared with those of multiple pulses of electrons. A significant decrease in the MN yield with increasing dose rates per pulse was observed, when dose was delivered by a single electron pulse. However, no reduction in the MN yield was observed when dose was delivered by multiple pulses of electrons. The decrease in the yield at high dose rates per pulse suggests possible radical recombination, which leads to decreased biological damage. Cellular response to the presence of very large numbers of chromosomal breaks may also alter the damage.
journal_name
Radiat Environ Biophysjournal_title
Radiation and environmental biophysicsauthors
Acharya S,Bhat NN,Joseph P,Sanjeev G,Sreedevi B,Narayana Ydoi
10.1007/s00411-011-0353-1subject
Has Abstractpub_date
2011-05-01 00:00:00pages
253-63issue
2eissn
0301-634Xissn
1432-2099journal_volume
50pub_type
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journal_title：Radiation and environmental biophysics
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journal_title：Radiation and environmental biophysics
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