222 A. V. LEBEDINSKY, V. M. MASTRYUKOVA AND A. D. STRZHIZHOVSKY 



DISCUSSION 



ARDASHNiKOV : Have yoii got experimental curves that could be conipared to the 

 ealcvilated theoretical one? 



LEBEDINSKY: Ycs, we have. Oiu- curves fit the experimental data. Even with 

 small irradiation doses the probability of recovery is small. Practically any 

 family of curves may be obtained, fitting in with experimental data. 



AKDASHNiKOV: I understand that any ciu've family can be obtained, but it is 

 important that the experimental curve should coincide with the theoretical one. 



meissel: I would like to laiow for how long after the manipulation on the ner- 

 vous system elements there occur the changes in the character of the nucleic 

 acids' fluorescence which you have established? In our experiments this jDhenom- 

 enon was not observed, even when more highly organized systems were used. 



LEBEDINSKY : For 24 to 48 hr. There is an old fluorescence test, known I believe 

 for the last 20 or 30 years, and used also by doctors. The fluorescence of the corneal 

 epithelium manifests itself within 10 to 15 min following surgery on these nervous 

 elements. 



MEISSEL : But in the case when fluorescein is used it is the membrane permeability 

 changes that account for the effect, whereas here the effect should be explained 

 in terms of the considerable changes of the cell metabolism connected with the 

 nucleic acid changes. 



LEBEDINSKY: At the time when a siu-face defect is produced, there are no pev- 

 meability changes as yet. For example, you cannot detect penetration of the 

 fluorescein into the anterior chamber of the eye. At the same time the test, 

 results of which have been reported, testifies to a considerable change in the 

 intermediary conjunctival membrane of the eye, induced by nervous ii'ritation. 



