Abstract: The cutting edge of a scalpel blade is resistively heated to a preselected constant temperature range by conduction of high frequency electrical currents within variable skin depths of a ferromagnetic conductor that is disposed on the blade in the region of the cutting edge.

Abstract: An improved catheter oximeter operates on radiation at three or more different wavelengths applied to and scattered back from blood under test to provide an indication of oxygen saturation and is considerably less sensitive to accuracy-degrading variations in the blood and its environment and in the oximeter measuring system.

Abstract: The extent, location, and severity of stenotic atherosclerotic lesions in the coronary arteries are determined by intravenous injection into the circulating blood of a number of small, discrete positron-emitting particles and by tracking the particles in three dimensions in the region of the heart using suitable gamma detectors disposed external to the patient's chest. The resolution and counting rates of the gamma detectors permit the sequence of positions of each particle to be recorded as a function of time as each particle flows through a coronary vessel. Data analysis of these recordings of particle position provide information about the velocity of blood flow through the course of each coronary artery. This velocity information is used to determine the extent, severity, and location of stenotic lesions of the coronary arteries.

Abstract: The cutting edge of a scalpel blade is heated to a preselected constant temperature range by conduction of high frequency current through the blade of ferromagnetic material in a region thereof which is in close proximity to a conductor positioned along the cutting edge. Selective heating of regions of the cutting edge that are locally cooled by the tissue contact during surgical cutting is provided by constructing the blade of ferromagnetic materials that have a Curie point in the operating temperature range and that provide large increases in magnetic permeability for temperature decrements below the Curie point.

Abstract: A surgical cutting instrument includes an electrically heated cutting edge and an automatic control system for maintaining the cutting edge at a constant high temperature for sterilizing the blade, cutting tissue, and cauterizing the incised tissue to reduce hemorrhage from the cut surfaces of the tissues (hemostasie).

Abstract: A photocell includes a metallic base electrode, a continuous, crystalline P-type semiconductive selenium layer less than about 50 microns thick, a thin tellurium layer interposed therebetween to metallurgically bond the base electrode to the selenium layer and to form an ohmic contact between the base electrode and the selenium layer, a thin N-type semiconductive cadmium selenide layer contiguous with the selenium layer and forming a photovoltaic heterojunction therebetween, a pellucid layer of at least one cadmium chalcogenide contiguous with the cadmium selenide layer and forming an ohmic contact therewith and a current collecting electrode on the cadmium chalcogenide layer. The sunlight conversion efficiency of the cell is at least about 3.0%. The efficiency can be further improved by doping the selenium layer to improve its conductivity and by providing an N-type layer of cadmium selenide and N.sup.+ cadmium oxide. This can be done by continuously varying the oxygen content of the N-type layer.

Abstract: Perivascular infiltration of liquid being administered to a patient is detected by the method of altering the temperature of a region of the patient's skin adjacent the site of a transcutaneous puncture and providing an output indicative of the difference between the altered skin temperature and the temperature of the infiltrated liquid.

Abstract: An improved method and means for preventing the intravascular needle of liquid infusion apparatus from clogging uses a delivery control means which operates in two modes at two liquid delivery rates. In the first operating mode, the delivery control means may be set to deliver liquid to a patient at a selected rate. In the second operating mode, the delivery control means supplies liquid at a slower rate which is sufficient to flush the needle. The transition from operation in the first mode to operation in the second mode is initiated in various ways in response to the volume of liquid delivered to a patient.

Abstract: A surgical cutting instrument includes an electrically heated cutting edge and a power supply system for maintaining the cutting edge at a constant high temperature for sterilizing the blade, cutting tissue, and cauterizing the incised tissue to reduce hemorrhage from the cut surfaces of the tissues (hemostasis). .Iadd.

Abstract: A surgical cutting instrument includes an electrically heated cutting edge and an automatic control system for maintaining the cutting edge at a constant high temperature for sterilizing the blade, cutting tissue, and cauterizing the incised tissue to reduce hemorrhage from the cut surfaces of the tissues (hemostasis).