Under consideration are the problems of preoperative radiotherapy for breast cancer patients with the use of 27 Mev electron beams and 17.5 and 27.5 Mev accelerator LUE-25 braking radiation. The methods for shaping figure fields was elaborated taking into account some individual anatomical features to provide simultaneous irradiation of all areas of regional metastases. Clinical testing of the suggested method for fast electron beams has demonstrated the treatment to be adequately tolerated and also the absence of grave reactions during it as well as of the immediate and early radiation complications. The time of preoperative radiotherapy was made twice shorter.

The data of dosimetry are reported as well as the technic of irradiation of patients with lymphogranulomatosis by 60Co gamma-quanta after the schedule involving large size figure fields on the national gamma-therapeutic machine "Rokus". Thirty two patients with the disease in stage I--III have been treated. It is shown that patients quite satisfactory undergo irradiation after a large-field variant of radical radiation therapy which, if necessary, may be associated with polychemotherapy according to MOPP schedule.

Some characteristics of detectors of bremsstrahlung and electron radiation of a DBM-I dosimeter which was used for the registration of absorbed doses on a new serial B5M-25 betatron are presented. The dependence of sensitivity of gallium-arsenide detectors upon the maximal energy of bremsstrahlung radiation spectra, rate of the absorbed dose and the temperature of the detector is defined. An assessment of the stability of operation of the dosimeter was made. (auth)

A scintillation telescope was used in investigating photoproton yield from C/sup 12/ as a function of bremsstrahlung energy. Simultaneous yield curves were plotted for energy rimges from 18.6 to 24.2, 24.2 to 29.9, and 29.9 to 38.7 Mev. with mean energies of 21.4, 27.0, and 34.3 Mev, respectively. All measurements were made at theta = 57.5 deg to the gamma beam with maximum telescope angular resolution plus or minus 6.0 deg . (R.V.J.)