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P Calzolari

Publications and source records attributed to P Calzolari.

23 records · Page 2Linked to original sources
PubMed1987

Effects of split-dose irradiation on survival and oncogenic transformation induced by 31 MeV protons in C3H10T1/2 cells.

Survival and oncogenic transformation were studied in C3H10T1/2 cells exposed to 31 MeV protons. Total doses of 0.5, 1 and 7 Gy were delivered as single and two equal fractions with various time intervals up to 10 h between doses. With split doses as compared with single doses to a total dose of 7 Gy, survival increased by a factor of 2.5 +/- 0.2, whereas the frequency of transformation per surviving cell declined by a factor of 3.1 +/- 0.5. Maximal split-dose recovery occurred within the first 5 h for both endpoints. Further, the transformation frequency decreased by factors of 3.1 +/- 0.6 and 1.5 +/- 0.3 respectively for total doses of 0.5 and 1.0 Gy split into two equal fractions. The data for 1 and 7 Gy are compatible with data in the literature for other low LET radiations.

Animals↗
PubMed1985

In vitro cell transformations induced by 31 MeV protons.

Experimental data are presented on the frequencies of transformations in C3H10T1/2 cells exposed to 31 MeV protons (LET = 1.83 +/- 0.02 keV/mum in tissue) in a dose interval between 0.25 and 7.0 Gy. The transformation frequency per surviving cell curve showed a marked change in slope over the dose range used. At higher doses, above about 2 Gy, it steepened very sharply in comparison with the lower dose range. If fitted to a power of the dose, the power in the higher range was about five times that in the lower range.

Animals↗
PubMed1984

[Radiosensitivity and effect of dose fractionation in cultured cells].

Survival, division delay and repair of sublethal damage were studied as a function of the cellular age in cells of EUE line exposed to 31 MeV protons, (LET of 1.83 keV/micron in tissue). The findings are compared with data reported in the literature on various mammalian cell lines exposed to X and gamma rays, common behaviours are pointed out and the characteristics parameters quantified. Survival varies with cell age and reaches a maximum value at mid S and its minimum at late G1; the ratio between maximum and minimum ranges between 1.5 and 15 depending on the survival level. Division delay resulted to be equal to 6 and 12% of the generation time per Gy for mid G1 and mid-late S respectively. All the investigated lines are able to repair as much as 50% of the sublethal damage within one hour.

Cell Division↗