relative biological effectiveness การใช้

• Megavoltage x-rays also have higher relative biological effectiveness than orthovoltage x-rays.
• See relative biological effectiveness for a discussion of this.
• There is no universally applicable conversion constant from rad to rem; the conversion depends on relative biological effectiveness ( RBE ).
• This is due to the high relative biological effectiveness of alpha radiation to cause biological damage after alpha-emitting radioisotopes enter living cells.
• The ICRP has assigned radiation weighting factors to specified radiation types dependent on their relative biological effectiveness, which are shown in accompanying table.
• RBE relative biological effectiveness quantifies the ability of radiation to cause certain biological effects, notably either cancer or beta radiation and ionizing photons.
• Also, neutrons have a higher relative biological effectiveness ( RBE ) for slow-growing tumours than X-rays, allowing for an advantage in tumour cell killing.
• The ratio of a dose of high-LET radiation to a dose of x-rays or gamma rays that produce the same biological effect are called relative biological effectiveness ( RBE ) factors.
• The radiation weighting factor represents the relative biological effectiveness of the radiation and modifies the absorbed dose to take account of the different biological effects of various types and energies of radiation.
• The engineer, whose name was not given, was exposed to 5 RBEs, or relative biological effectiveness units, which is the maximum permissible amount for nuclear workers over one year, the report said.
• Consequently, in living tissue, neutrons have a relatively high relative biological effectiveness, and are roughly ten times more effective at causing biological damage compared to gamma or beta radiation of equivalent energy exposure.
• When alpha particles emitting isotopes are ingested, they are far more dangerous than their half-life or decay rate would suggest, due to the high relative biological effectiveness of alpha radiation to cause biological damage.
• The rad and rem are essentially equivalent for almost all nuclear medicine procedures, and only alpha radiation will produce a higher Rem or Sv value, due to its much higher Relative Biological Effectiveness ( RBE ).
• Relative biological effectiveness ( RBE ) depends on radiation type described by particle charge number, Z, and kinetic energy per amu, E, and varies with tumor type with limited experimental data suggesting leukemia's having the lowest RBE, liver tumors the highest RBE, and limited or no experimental data on RBE available for cancers that dominate human cancer risks including lung, stomach, breast, and bladder cancers.