title: Haemopoietic stem-cell kinetics during continuous irradiation.
abstract: Analysis of the kinetics of the biphasic response of haemopoietic stem cells to chronic low dose-rate irradiation indicates that a highly radiosensitive delay of entry into cell-cycle by Go cells may be responsible for the initial, apparently dose-rate-independent, phase of the dose-response curve. The second component of the curve appears to be the result of a combination of two factors: a relatively decreased differentiation demand on stem cells due to increased amplification in the transit-committed precursor cells, and a uniform shortening of the cell-cycle--including the S period--in the stem cells.
mesh_terms: D000818:Animals; D002587:Cesium Isotopes; D002999:Clone Cells; D004307:Dose-Response Relationship, Radiation; D004912:Erythrocytes / Q000378:metabolism; D005260:Female; D005720:Gamma Rays; D006412:Hematopoietic Stem Cells / Q000528:radiation effects*; D007501:Iron / Q000378:metabolism; D007504:Iron Radioisotopes; D008297:Male; D051379:Mice; D008938:Mitosis / Q000528:radiation effects; D011830:Radiation Effects; D013154:Spleen / Q000166:cytology; D013997:Time Factors
chemical_list: D002587:Cesium Isotopes; D007504:Iron Radioisotopes; D007501:Iron