| 摘要 |
1,035,205. Surgical appliances; toys. YEDA RESEARCH & DEVELOPMENT CO., Ltd. Nov. 6, 1963 [Nov. 30, 1962; July 5, 1963 (2); Aug. 26, 1963], No's 45437/62; 26840/63; 26842/63; and 33765/63. Headings A5R and A6S. In order to propel a capsule or similar device through ducts in the body, forward motion is induced by vibration or rotation resulting from interaction between a permanent magnet within the device and an external, alternating magnetic field. The arrangement is illustrated in Figs. 2a and 2b in which a magnet 1 is embedded in a flexible body 4 having a flat tail 5. Oscillation of the magnet by an applied alternating field results in a flailing action of the tail which drives the device forward when immersed in a fluid. Various other forms of tail are also described and one other form of device has a screwlike extension so that by using a transversely placed magnet, which results in continuous rotation of the device a screw action is obtained for the forward movement. Still further forms employ laterally extending, trailing wires which drive the device forward by engaging the walls of the blood vessel &c. Such a device may be introduced into the arterial system and, in order to direct it to a desired location the patient is placed between two assemblies of coils which are suitably energized by switching, the movement of the device being followed by X-rays and a fluorescent screen. One form of device for releasing a drug at a desired location comprises a magnetized, hollow container, which serves as the magnet used for propulsion, having a closure cover made of an alloy which ceases to have magnetic properties at temperatures above 40‹C. This cover is held in position by the magnet until the correct location is reached and then its temperature is raised, by a high frequency field, so that it is no longer attracted. The drug enclosed in the container is thereby allowed to escape and, subsequently, the temperature is reduced to normal so that the cover is again held in position. Apart from administering drugs the device may be employed for the physical removal of obstructions in body ducts. |
