Abstract: Microspheres are permanently marked with non-radioactive stable isotopes of elements suitably detected by neutron activation analysis. The marked microspheres are suitable to permanently label diverse things. For example, families of stable-multiple-isotope-marked microspheres injected into an animal become lodged by the circulating blood within selected tissues of an animal during blood flow analysis experimentation. Absolute and relative abundances of these stable-isotope-marked microspheres residing within harvested tissues are readily accurately automatically measured in situ within the harvested tissue samples by neutron activation analysis. The quantitatively measured abundance of the isotopes, and associated microspheres, are accurately indicative of the former flow of blood containing the microspheres to the tissue.

Abstract: Microspheres are permanently marked with non-radioactive stable isotopes of elements suitably detected by neutron activation analysis. The marked microspheres are suitable to permanently label diverse things. For example, families of stable-multiple-isotope-marked microspheres injected into an animal become lodged by the circulating blood within selected tissues of an animal during blood flow analysis experimentation. Absolute and relative abundances of these stable-isotope-marked microspheres residing within harvested tissues are readily accurately automatically measured in situ within the harvested tissue samples by neutron activation analysis. The quantitatively measured abundance of the isotopes, and associated microspheres, are accurately indicative of the former flow of blood containing the microspheres to the tissue.

Abstract: A flexible elastomeric annulus-shaped membrane having a shape-retentive memory and exerting a force so as to assume and to maintain a predetermined closed-loop geometric shape, normally a circle, fits circumferentially about the cervix os of a human female so as to hold and retain medical instrumentation probes, preferably two opposed wire-connected ultrasonic transducers of a real-time transit-time ultrasonic monitor of cervical dilatation and effacement. The annular membrane may optionally extend as a tube downwards in the vaginal canal, in the manner of a female diaphragm, as to shield the wires from the walls of the vagina. The membrane expands and contracts with such cyclical variation in the dilatation and effacement of the cervix os as occurs from the earliest onset of labor until imminent childbirth.

Abstract: The onset of spontaneous abortion or premature labor of a pregnant human female is continuously monitored, potentially for periods of several months and longer, by a real-time transit-time ultrasonic monitor of the dilatation and/or effacement of the cervix os, preferably by a computerized ambulatory monitor. The preferred computerized monitor sounds an alarm upon the detection of variably present conditions, normally the compound conditions of five or more 10% cyclical variations in the dilatation or effacement of the cervix os within a period of one hour, coupled with a greater than 1 centimeter increase over baseline of either dilatation or effacement, which compound conditions normally indicate the early onset of labor. The monitor connects to an infusion pump, likewise preferably ambulatory, for directing and controlling the infusion of one or more tocolytic, labor-preventing, drugs if labor continues.

Abstract: Preferred transducers in the substantial shapes of a three-dimensional bodies, normally spheres or cylinders, emit ultrasound omni-directionally. The transducers are secured to the wall of the cervix uteri of human female, preferably by a barb or corkscrew coil, so that a straight line ultrasonic acoustic path exists between them. An ultrasonic transit time sonomicrometer detecting a variable propagation delay between the transducers dependent upon the dilatation or effacement of the cervix uteri serves as a ultrasonic cervimeter. Cervical dimension, and changes in dimension, developed by the ultrasonic cervimeter directly in millimeters are (i) validated for reasonableness, (ii) monitored so as to generate several alarms upon the occurrence(s) of several predetermined conditions, (iii) displayed, and (iv) archived all in a battery-powered ambulatory instrument.

Abstract: Microspheres labeled with a dye for which the absorption spectra is known permit the measurement of blood flows, particularly regional myocardial blood flow (RMBF), without radiation safety concerns and radioactive waste disposal problems. Polystyrene spheres, nominally of diameter 15.+-.0.1 [SD] um and density 1.09 g/ml, are dyed with a fixed quantity, nominally 30 picograms per microsphere, with one of several, nominally 5, colored dyes. The colored microspheres (CM) are injected into the left atrium or into a coronary perfusion. The CM are extracted from myocardium and blood by digestion with KOH and subsequent microfiltration. The dyes are then recovered from the CM within a defined volume of a solvent, and their concentrations are determined by spectrophotometry. The composite absorbance or emission spectra of several dyes are mathematically resolved using matrix inversion. Leaching of dye from the CM was less than 0.