Abstract: A discontinuity detector detects a sudden change or discontinuity in a medium moving relative to the detector such as a liquid plug in a gas flowing along a conduct, an air bubble in a liquid, or a change form one liquid or gas to another. It has a sensor which senses the discontinuity and a circuit which compensates for gradual changes in the medium or sensor, but responds to the sensed discontinuity. The preferred circuit also determines that the sensor is functioning properly and is properly set up for sensing the discontinuity. The preferred circuit is an analog-to-digital delta modulator which periodically resets a clock pulse counter until a discontinuity is sensed. The clock pulses then increment the counter to a higher-than-normal count to signal the discontinuity. The preferred embodiments are intended for detecting discontinuities in patient gas or liquid supplies in a medical diagnostic or therapeutic instrument.

Abstract: A process and reagent for determining the presence of fecal occult blood in a test sample using a guaiac-peroxidase test matrix and a means for inhibiting peroxidase enzyme interferences which combines the partial denaturing of peroxidase enzyme protein using a protein-hydrogen bond cleaving agent, with the removal of metals necessary for efficient peroxidase enzyme activity wherein the improvement comprises dissolving said reagent for cleaving protein-hydrogen bonds in an alcohol-water solvent before adding said reagent to the sample.

Abstract: A sampling system for stool analysis provides an elongated handle and a cylindrical coring device, said handle including means for releasibly holding said coring device. The coring device is inserted into the stool to collect a representative sample. The sample is removed for analysis, as required.

Abstract: A system for measuring the flow rate of electrolytic fluids includes a flow cell which has a cylindrical flow channel receptive of the fluid flow to be measured and a pair of spaced apart electrodes configured to conform to the cylindrical surface of the flow channel and to be flushed therewith. The electrodes are electrically conductive and inert to the fluid of the flow and a channel is configured to effect contact of the electrodes with the fluid flow for a desired range of flow measurement. A monopolar pulse train is applied across the electrodes to effect a cell impedance across the electrodes which is inversely proportional to the rate of flow.

Abstract: A jet ventilator control system produces a periodic pulse signal either asynchronous or synchronous with a patient's pulse rate. It is proportional in frequency to the number of jet ventilation pulses to be applied to the patient per unit time and is digitally programmable to adjust the delay and duty cycle of the pulse signal within the period defined by the produced pulse. The duration and duty cycle adjusted pulse signals effect the application of jet ventilation pulses corresponding thereto to the patient.

Abstract: A delta modulator has its feedback loop components selected to put the delta modulator into slope overload in response to the QRS wave of an EKG signal for detecting the same.

Abstract: A humidifier-injector for use with a jet ventilator.

Abstract: A process and apparatus for measuring the catheter fluid pressure of a patient wherein a pressure transducer is used to convert the pressure into an electrical signal and a pressure indicator indicates the pressure corresponding to the electrical signal. A turnable active filter is disposed in the signal path between the transducer and the pressure indicator and the frequency parameters of the filter are adapted to that of the catheter in real time.

Abstract: A method and a surgical stapling instrument for the stapling together of the free ends of two hollow organs. The instrument comprises an elongated tubular body, a base unit concentrically connected to the body and a head unit mounted to the body and concentric therewith for relative movement with respect to the head unit over a range wherein the inner end thereof is spaced apart from the outer end of the base unit and wherein the inner end of the head unit is substantially adjacent to the outer end of the base unit. Holding elements are mounted on the base and head units and project outwardly from the outer and inner ends thereof respectively to extend between the base and head units and are disposed inwardly from the outer periphery of the ends of the base and head units for holding the free ends of the hollow organs inwardly of actuatable stapling and cutting mechanisms to maintain the free ends in position on the base and head portions while the base and head units are moved towards one another.