Search PubMed⌕ Search

Biomedical subjects

V Strnad

Publications and source records attributed to V Strnad.

50 records · Page 3Linked to original sources

[Reoxygenation of tumors of the uterine cervix during combined radiotherapy using low dose gamma-neutron irradiation with californium-252].

A polarographic method was used to follow the changes in oxygenation of a tumour of uterus cervix after intracavital irradiation by 252Cf by a physical dose of 2 Gy, applied at the beginning of a therapeutic cycle of combined radiotherapy. The results reached are compared with the results of tumour oxygenation in the course of a conventional therapeutic procedure. It has become apparent that even after the irradiation of a tumour of uterus cervix by a small dose of gamma-neutron radiation with 252Cf there is, beginning with 2nd week of therapy, a significant reoxygenation of the tumour population. The changes of oxygenation after a conventional irradiation have been less marked and reached, in the 4th week of therapy, only marginally significant increase. Differences in reoxygenation of tumours of uterus cervix were confirmed by analysis of the oxygen test. The importance of tumour reoxygenation after the application of 252Cf source of radiation for facilitation of its regression in a combined treatment with Californium-252 and gamma irradiation is discussed.

Brachytherapy↗

[Manual afterloading applicators for intracavitary brachytherapy].

A technical description of uterovaginal and rectal applicator system of manual afterloading is described. A simple solution while using domestic materials covering the requirements of present-day brachytherapy. The applicators proved to be suitable for gamma radiation sources as well as for gamma-neutron radiation of 252Cf sources.

Brachytherapy↗

[Regression of cervix uteri neoplasms in combined radiotherapy using low dose gamma-neutron irradiation].

The authors compared the results in the regression of uterus cervix tumour after intracavital therapy with gamma-neutron irradiation by 252cf and conventional sources of radiation gamma 226Ra in the course of a combined radiotherapy procedure. On the basis of a randomized study in 20 patients for a group it became obvious that due to the irradiation of the tumour in the initial phase of therapeutic cycle by physical dose 2 Gy of neutron component of 252Cf in the point A there was an increased regression of the tumour process causing in the 6th week since the beginning of the therapy a significant difference in the size of the tumours in both groups of patients. The time period required for 50% tumour reduction from the beginning of the therapy proved to be 23 days in patients treated with the 252Cf nuclide as compared with 48 days in the group of patients after conventional therapy.

Brachytherapy↗

Optimization of radiation therapy in prostatic cancer.

The results of a study on the optimization of external irradiation of prostatic cancer are discussed. The study was performed with the aid of an automatic water phantom, an automatic densitometer, and a computerized treatment planning system using an anthropometric phantom Alderson. The following parameters were studied: Dose gradient, the size of areas of selected isodoses, and the shape of the 90% isodose. At present, we consider that the twosector biaxial arc technique characterized by an arc angle of 120 degrees, a distance of the arc axes of 3 cm, employing a 20 MeV X-ray of a linear accelerator is the optimal technique for target irradiation of carcinomas of the prostate.

Humans↗

Reaction of mouse lung tissue on the experimental airborne Klebsiella pneumoniae infection.

There are described the histological changes in the lung tissue of mice after airborne infection with the strains of Klebsiella pneumoniae CNCTC Klp 80/66 and CNCTC 82/67 whose clearance is significantly different. Using the strain Klp 82/67, which is fairly prompt eliminated from lungs, no morphological changes in the mucous membrane of bronchi were found. Using the strain Klp 80/66, which is characterised by a multiplication of organisms in the lungs already in the initial phase of infection without any remarkable adaptative phase, the accumulation of neutrophils in the walls and on the surface of bronchi was observed. The accumulation retarded during 48 hours when mostly the mononuclear cells were present. Uptake of 3H-thymidine in the lung tissue in vivo demonstrated that the proliferation response of bronchial lymphoid tissue is a relatively early reaction. Histological examination of spontaneously died animals revealed the changes characteristic for the purulent bronchopneumonia. The pathogenic activity of various Klebsiella pneumoniae strains is obviously conditioned by at least two factors, i. e. by surface structures determining the rate of bacterial elimination from the lungs and by the lipoprotein components of the cell walls inducing the leucocytes mobilization into bronchial tissue.

Aerosols↗

[Use of respiratory mixture containing 8.0-8.5% of oxygen in hypoxic radiotherapy of cervical neoplasms].

Combined radiotherapy of patients with cervical carcinoma of stages IIb and IIIb was conducted. Hypoxia (8.0-8.5% of O2 in the respiratory mixture) was used in microfractionated (2 Gy) irradiation of metastatic spreading zones. When irradiating under conditions of hypoxia, the number of fractions was brought up to 28 as compared to 20 in control. Despite a 40%-increase of the dose, seriousness of radiation reactions and remote injuries remained at the same level. It is found that patients endure well the respiratory mixture for 6 min. necessary for irradiation.

Combined Modality Therapy↗