Big Chemical Encyclopedia

Chemical substances, components, reactions, process design ...

Articles Figures Tables About

Oxygen enhancement ratio

In vitro clonal tumor cell studies have demonstrated the severe cytotoxicity of a-particles delivered by At single exponential cell survival-dose curves were obtained, with (37% survival) values of 29-48 cGy and 57-73 cGy for Chinese hamster V-79 (5J ) and HEp2 cells, respectively (55). In both studies the oxygen enhancement ratio (OER) was found to be slightly greater than unity, probably resulting from the low-LET components of At decay (see Fig. 5). In biological systems, such a-particle emissions enable comparable cytotoxicities to be effected in both hypoxic and euoxic tumor cell populations. [Pg.82]

A reduction in the oxygen enhancement ratio (OER) with increasing LET... [Pg.756]

OER, Oxygen enhancement ratio MER misonidazole enhancement ration Cya, cysteamine... [Pg.437]

FIGURE 7. Dependence of relative biological effect (RBE) and of oxygen enhancement ratio (OER) on the linear energy transfer (LET) of radiation. Reprinted from Brown, Appl. Radiat. Isot., 37, 789 (1986) (Reference 84) by kind permission of Elsevier Science Ltd, The Boulevard, Langford Lane, Kidlington, OX5 1GB... [Pg.808]

Figure 18.S.B illustrates a matrix effect during irradiation in air and in an oxygen deficient hypoxic) system. OER, the oxygen enhancement ratio, is the relative dose increase needed to produce the same biological effect in the hypoxic as the oxic case. For X-rays and 7, cell survival increases when oxygen is reduced the addition of oxidants has the opposite effect. This indicates that it is the oxidative radiolysis products of water which are most damaging to the cell. However, no oxygen effect is se for a radiation, thereby supporting the model of double strand breaks by direct hits of the a s. Figure 18.S.B illustrates a matrix effect during irradiation in air and in an oxygen deficient hypoxic) system. OER, the oxygen enhancement ratio, is the relative dose increase needed to produce the same biological effect in the hypoxic as the oxic case. For X-rays and 7, cell survival increases when oxygen is reduced the addition of oxidants has the opposite effect. This indicates that it is the oxidative radiolysis products of water which are most damaging to the cell. However, no oxygen effect is se for a radiation, thereby supporting the model of double strand breaks by direct hits of the a s.
A reduction in the oxygen enhancement ratio (OER) with increasing LET A reduction of the differences in radiosensitivity related to the position of the cell in... [Pg.755]

Frankenberg-Schwager M, Frankenberg D, Harbich R (1991) Different oxygen enhancement ratios for induced and unrejoined DNA double-strand breaks in eukaryotic cells. Radial Res 128 243-250... [Pg.269]

Fig. 8.1. A typical survival curve for CHO cells in O2 and N2 fitted using the a model and showing the oxygen enhancement ratio. From Reference 8. Fig. 8.1. A typical survival curve for CHO cells in O2 and N2 fitted using the a model and showing the oxygen enhancement ratio. From Reference 8.
Fig. 24. Dependence of oxygen enhancement ratio on LET for different particles. (Data redrawn from [79,80])... Fig. 24. Dependence of oxygen enhancement ratio on LET for different particles. (Data redrawn from [79,80])...
See other pages where Oxygen enhancement ratio is mentioned: [Pg.488]    [Pg.18]    [Pg.2]    [Pg.432]    [Pg.473]    [Pg.268]    [Pg.590]    [Pg.5]    [Pg.1687]    [Pg.184]    [Pg.97]    [Pg.111]   
See also in sourсe #XX -- [ Pg.432 , Pg.437 , Pg.440 ]

See also in sourсe #XX -- [ Pg.4 ]

See also in sourсe #XX -- [ Pg.1687 ]



SEARCH



© 2024 chempedia.info