Abstract: The present invention provides methods of culturing or storing cells for a prolonged period while suppressing a loss of functions of the cells during storage, by applying centrifugal force or pressure such as hydraulic pressure to the cells to form compact bodies, particularly aggregates, in which a state of high contact or a high contact frequency is maintained between the cells, and then culturing, storing or inducing differentiation in the cells in this aggregate state.

Abstract: The present invention provides a method capable of simultaneous processing of plural test samples for the receptor binding property of a chemical substance, which does not require immobilization of the receptor or a special device, and a reagent to be used for this method. That is a method for assaying the receptor binding property of an assay target substance is provided, the method comprising the steps of (a) competitively reacting a known concentration of a ligand and the assay target substance with a known concentration of the receptor in a solution, (b) measuring, without physically removing the ligand bound with the receptor prior to the assay, the amount of a free ligand in the solution using one or more antibodies against the ligand, and (c) determining the receptor binding property of the assay target substance using the amount of the free ligand as an index.

Abstract: In an expandable part positioned on the tip end side of the catheter, protruding parts are produced in specific regions when the expandable part is expanded through the difference in elasticity between two materials having a different elasticity to one another. The structure is made to be such that low-elasticity regions and high-elasticity regions are disposed in the expandable part, and when pressure is applied the high-elasticity regions expand more than the low-elasticity regions, thus becoming the protruding parts. Alternatively, the structure is made to be such that two materials having a different elasticity to one another are made into a two-layer structure of an inner layer and an outer layer, and voids are provided in the layer formed from the low-elasticity material, so that when pressure is applied, parts of the layer formed from the high-elasticity material corresponding to the void parts become the protruding parts.