Abstract: A cryosurgical probe having a probe head which is cooled by Joule-Thomson cooling, and is then used to freeze bodily tissue during a surgical procedure. A steerable catheter is connected between the probe head and a probe handle to enable the probe head to be guided with safety and precision along arteries of the body to the target area.
Abstract: A magnetic resonance examining apparatus of heart beat synchronous type in which one heart beat period is substantially equally divided to provide a plurality of phases, and at least some of those phases are selected as imaging phases so as to obtain nuclear magnetic resonance images. In the apparatus, spin excitation is effected at all the phases including those where nuclear magnetic resonance images are obtained and those where nuclear magnetic resonance images are not obtained, so that all the phases have the same longitudinal relaxation time after spin excitation. Therefore, nuclear magnetic resonance signals free from variations of the longitudinal relaxation time can be obtained to provide clear nuclear magnetic resonance images at anyone of the plurality of phases.
Abstract: Electronic filters are applied to analog signals representative of eye movement and head movement, obtained from detectors attached to a simple headgear, to provide satisfactory information for automatically reporting an individual's sleep state. The filters determine whether there has been substantial eye and head movement in a given period. Each filter then generates binary output signals representing movement (or the absence of it). Noise filters and a comparison filter are then applied to the binary output signals to predict sleep state; REM sleep; NREM sleep; or wakefulness.
July 8, 1987
Date of Patent:
June 6, 1989
President & Fellows of Harvard College
J. Allan Hobson, Adam Mamelak, Rita Helfand, Peretz Lavie