[Enhancement of the effect of radiotherapy of Guerin's carcinoma by tinidazole]. / Usilenie luchevogo vozdeistviia na kartsinomu Gerena s pomoshch'iu tinidazola.

Tinidazol, an electron-acceptor compound, was studied for its influence on the effectiveness of radiation treatment of Guerin's carcinoma. It was shown in terms of tumour regression, percentage of inhibition, time of tumour volume doubling, rate of the tumour growth renewal and average survival that in the presence of tinidazol, the antitumour effectiveness of radiation treatment is 1.6-2.0 times as high as radiation alone. Morphologic studies confirm the ability of tinidazol to enhance the radiation damage.

[Accumulation and localization of 67Ga citrate in cancerous lung tissue during diagnostic use of the preparation]. / Nakoplenie i lokalizatsiia 67Ga-tsitrata v opukholevoi tkani legkikh pri diagnosticheskom ispol'zovanii preparata.

Altogether 89 patients were examined using scintigraphy with 67Ga-citrate. Radiometric, scintigraphic, radioautographic and histological investigation of the operation material of 15 patients was conducted. The diagnostic accuracy was 92.1%, sensitivity 98.6%, specificity 75%. The investigation of the operation material showed that RP accumulation in the peripheral part of tumor was 4-4.5 times higher and in its central part 2-3 times higher than in the unaffected pulmonary tissue. Elevated RP accumulation was found in the capsular wall in inflammatory processes as well as in lymph nodes with anthracosis. Recovered silver grains on histoautoradiograms of tumor tissue zones were mainly localised around isolated cells and their groups in the intercellular space.

[Prospects for using the cryogenic factor in the radiation therapy of tumors]. / Perspektivy ispol'zovaniia kriogennogo faktora pri luchevoi terapii opukholei.

Experimental studies with 640 mongrel male rats with transplants of Guerin carcinoma and DMBA-induced tumours were performed. Separate groups of animals were subjected to isolated effects of cryodestruction, radiation therapy with total doses of 60 or 30 Gy and combined cryoradiation treatment by different schedule. The study revealed that an enhanced efficiency of combined treatment is achieved essentially by a two-fold decrease in the total irradiation dose in combination with tumour focal cryodestruction.

[Cell viability after cryodestruction of the tumor]. / Zhiznesposobnost' kletok posle kriodestruktsii opukholi.

By histoautoradiography DNA was determined in the Heren carcinoma cells during the first 6 days after cryosurgery of the tumor. During 2.5 days after cryosurgery no labeled cells in the cryodestructed tissue were detected. The DNA synthesizing cells were revealed in separate portions of some tumors 66 hours and longer following cryosurgery. The absence of labeled cells during 66 hours since the moment of cryoexposure indicates the block of DNA synthesis in cryoresistant tumor cells. It evidences that the cells which remained viable after cryosurgery were the cause of the recurrences observed.