Faraday-active Fabry-Perot resonator: transmission, reflection, and emissivity.

The propagation of light within a semiconductor Faraday-active Fabry-Perot resonator is investigated theoretically and experimentally. It is shown that an external magnetic field radically changes the angular and spectral characteristics of transmission, reflection, and emissivity of the resonator not only for polarized, but also for unpolarized, light. Suppression of interference patterns and phase inversion of the interference extrema were observed in both monochromatic and polychromatic light.

[Determination of glomerular filtration in children using 99mTc-DTPA and the sequential gammagraphy method].

The method of sequence scintigraphy of the kidney with 99mTc-DTPA (diethylene triamine pentacetic acid) and subsequent determination of glomerular filtration rate by means of a gamma camera and computer were applied in examining 160 children with different diseases of the kidneys and urinary tract. By modifying the commercial computer program a study with quantitative evaluation of some functional parameters was designed, involving also the determination of the overall and of separate values of GF 99mTc-DTPA according to G. Gates.

Dynamic 99mTc-DTPA renal gammagraphy with glomerular filtration rate determination.

Using the method of 99mTc-DTPA (diethylenetriaminepentaacetic acid), sequential renal gammagraphy with subsequent glomerular filtration rate determination by means of a gamma-camera and computer, a total of 285 patients with suspected renal and urinary tract diseases, subjects after surgery on these organs or those serving as controls after drug therapy were examined. With the help of a modified computer user's program, a study was designed to perform quantitative evaluation of some functional parameters as well as determination of total and separate glomerular filtration rate values by 99mTc-DTPA according to Gates. The benefits of the method employed in our study are that it is non-invasive, rapid, atraumatic, with low exposure to radiation while offering a broad range of applications in routine diagnostic practice of nephrology, and especially so in paediatric patients.

Experiences with bone scanning in differential diagnosis of local bone lesions.

Because some primary tumours often metastasize to the skeleton, their early detection is essential for further therapy and prognosis. Radiographic examination is not sufficiently sensitive for early detection of bone metastases, because it can reveal the typical sign of metastases--decalcification--only after loss of 30-50% of the original amount of calcium from bone tissue (18). Bone scanning with bone-seeking radiopharmaceuticals represents a viable technique for early detection of bone lesions, especially early metastatic disease.