[A method of quality assurance of dynamic wedges].

Background: One of the important prerequisites for using a virtual wedge is the availability of an appropriate method for quality assurance. A simple method to determine wedge angles has been developed.

Material And Methods: A formula based on the exponential attenuation curve has been derived, that allows for the calculation of the wedge isodose angles based on 2 measurement points perpendicular to the central ray.

Development of a fast optimization preview in radiation treatment planning.

Purpose: Having the capability of fast previewing an expected optimization result for a defined combination of optimization parameters is essential to reach a better optimization result. In order to achieve this goal, the well-tried Cimmino optimization algorithm requires modification.

Materials And Methods: Usually, the speed of convergence of some iterative algorithms is restricted to a bounded relaxation parameter.

Effects of sulfhydryl-containing compounds on nitroglycerin-induced coronary dilatation in isolated working rat hearts.

The effects of various compounds on the time course of the coronary dilating response to nitrovasodilators were studied in working rat hearts. Continuous administration of 100 microM glyceryl trinitrate (GTN) to the perfusate induced a rapid increase in coronary flow. The flow decreased to about 40% of the initial flow rise within 20 min and remained constant during the following 40 min.