On the mechanism of reactive oxygen species generation in tumour cells subjected to the phototoxic action of haematoporphyrin derivative : effect of heatingTšekulajeva, Ludmilla; Ševtšuk, Igor; Tšekulajev, Vladimir; Oginskaja, JelenaProceedings of the Estonian Academy of Sciences. Chemistry2007 / 1, p. 14-37 : ill