No abstract available

No abstract available

[en] Short communication

No abstract available

[en] Differences of yttrium biokinetics after application to male tumor-bearing mice of ⁸⁷Y-citrate were studied in comparison to a ⁸⁷Y-NTA-EDTMP-Ca mixture after variation of both the manner of application (intraperitoneal vs. intratumoral) and the tumor type (mamma carcinoma vs. melanoma). The application of ⁸⁷Y as NTA-EDTMP-Ca preparation led - in comparison to the citrate form applied so far - to a similar radionuclide tumor accumulation and distinctly lower extratumoral radioactivities in liver, spleen and skeleton with clearly more favorable tumor/background ratios. Melanomas showed a significantly higher radioactivity accumulation (factor 2-3) after injection of ⁸⁷Y-NTA-EDTMP-Ca than mamma carcinomas. Intratumoral application led to high initial radioactivities in the tumors. Radioactivity concentrations which are comparable with those after intraperitoneal application were achieved within 4 h after intratumoral application. The application of the EDTMP-containing mixture promises in comparison to the traditional citrate form higher radiation doses in the tumor related to the whole-body radiation exposure. The consequences for a possible tumor therapy will be further investigated. (orig.)

[en] Brief summaries of the principal accomplishments of this project on the development of quantitative SPECT for high energy photons (87Y, 19F) and stability testing of 87Y-labeled antibodies in the nude mouse model, development of an unified approach to photon and beta particle dosimetry, quantitative SPECT for nonuniform attenuation, and development of patient-specific dosimetry in radioimmunotherapy

[en] The odd-A Y isotopes ⁸⁵Y and ⁸⁷Y are studied in a semimicroscopic model which couples the proton quasiparticle motion to the quadrupole vibrations of the neighboring even core. The calculated results are in good agreement with recent (³He, d) data

[en] Recently, there has been an increasing demand for the use of medical radioisotopes for diagnosis and therapy of certain diseases. To meet the increased demands of radioisotopes for medicine, they need to be produced in larger amounts. We have studied the (p,xn) reactions on all stable isotopes, viz ., ^84;86;87;88Sr. The cross-section data for (p,xn) reactions on ⁸⁴Sr are not available and therefore, we can make a prediction of the same. The methodology is to first predict the total reaction cross section. In the present work, the excitation functions for ^84;86;87;88Sr(p,n)^84;86;87;88Y and ^84;86;87;88Sr(p,2n)^83;85;86;87Y reactions have been calculated within the framework of the nuclear statistical model

[en] The isomer ratio dependence of yields of photonuclear reaction on Bremsstrahlung maximal energy in 23-35 MeV range was studied by the method of induced radioactivity. The gamma spectra of irradiated target was measured by spectrometer on the basis of germanium detector with multichannel analyzer and the identification of population of isomer and ground states was done on gamma levels 381 and 484 keV. (A.A.D.)

[en] The influence of the ligands ethylenediaminetetramethylene phosphonic acid (EDTMP) and citrate (CIT) on the biodistribution of radio-yttrium in rats bearing a DS-carcinosarcoma was compared. ⁸⁸Y-EDTMP and ⁸⁷Y-CIT were i.v. injected into the same animals. Faster blood clearance and higher renal excretion were observed for the EDTMP-ligand. Of high practical interest is the reduced liver uptake of radio-yttrium (by one order of magnitude) with the EDTMP complex. Since bone and tumour accumulation is only weakly influenced, high tumour-to-liver ratios (up to 14) were observed. We propose to use EDTMP or similar complex ligands for liver blocking when radionuclides like ⁹⁰Y, ¹⁶⁹Yb, ²²⁵Ac or other group 3 elements are to be applied in endoradionuclide therapy technique. (Author)