Fe3O4 nanoparticles were coated with a layer of citric acid, forming coordination bonds between citrate ions and iron ions. The resulting aqueous citrate ferrite colloid was used as a T2-weighted MRI negative contrasting agent. Sequential i.v. doses of citrate ferrite and Magnevist led to increases in MRI image contrast for 40 h and brightness for 30 min; scanning using a Bruker Biospec BC 70/30 USR biospectrotomograph yielded enhanced MRI images. This enhancement of MRI images was used to monitor oncogenesis during magnetohydrodynamic thermochemotherapy (MT) of mammary adenocarcinoma Ca 755 in female C57Bl/6j mice. Dextran ferrite colloid containing cyclophosphamide was tested as a magnetically directed antitumor agent using MT. Treatment of non-infiltrating tumors of volume ≈ 30 mm3 with six sessions of MT each lasting 30 min at 46°C led to 40% tumor regression and 300% increases in survival time. Treatment of infiltrating tumors of volume ≈ 300 mm3 in the same conditions yielded a 200% increase in survival time.

Intravenous administration of dextran-ferrite sol was used to amplify T 2 -weighed echo gradient (500/15) scanning MR images with visualization of the invasion margins of tumor cells into healthy tissues, along with macro-and micrometastases, in animals with lymphocytic leukemia and Ehrlich and Lewis carcinomas. Magnetohydrodynamic thermochemotherapy (MTCT) using a cyclophosphamide-containing magnetic fluid (saturation magnetization (M s ) 8.6 kA/m, pH 7.4, ζ + 13 mV) at 46°C for 30 min in an alternating magnetic field (0.88 MHz, 7.2 kA/m, 0.15 kW) with aspiration of necrotic material (ANM) produced regression of P388 tumors of volume ∼110 mm 3 in BDF1 mice prior to metastasis by 40%, with an increase in lifetime (ILT) of 310%; in tumors of volume ∼330 mm 3 after metastasis and MTCT-ANM with cyclophosphamide pretreatment, ILT was 220%.

This article is devoted to the thermal radio emission of the disturbed water surface in a small-scale approximation. It describes the numerical calculation method of surface emittance with an arbitrary number of surface waves based on the small perturbation method and boundary conditions of Leontovich.There are description and some results of the experimental test of this method as well.