Abstract: A line voltage monitor which can measure d.c. and RMS a.c. voltage and frequency, maximum and minimum RMS voltage, which displays input voltage, and computes and displays % regulation from the measured maximum and minimum voltage values. Analog input circuitry attenuates and squares the input voltage. A voltage-to-frequency converter produces logic pulses at a rate proportional to the squared signal. A 16-bit counter integrates V.sup.2 by accumulating pulses from the voltage-to-frequency converter. A second 16-bit counter increments at a 1 MHz rate to determine the cycle period T of the input. A microcomputer divides the .intg.V.sup.2 value by the period T and then takes the square root, yielding the RMS value of the input voltage. The microcomputer can be switched to determine the % regulation and the input frequency, and can be used to enable display of V.sub.max, V.sub.RMS (t) or V.sub.min, as well as the regulation.

Abstract: A system for monitoring low molecular weight compounds in blood plasma in the body by optical means includes a chamber which can be inserted into the blood stream and which contains specific receptor sites for the plasma constituent to be analyzed. The chamber interior is isolated from the blood by a dialysis membrane which permits the plasma constituents to diffuse into the chamber. A competing ligand for the receptor sites is placed within the chamber, but due to its relatively large molecular size the competing ligand cannot escape through the dialysis membrane into the bloodstream. Light emitted or absorbed by the competing ligand gives a measure of the concentration of the selected low molecular weight compounds in the blood.

Abstract: A medical implement and more particularly a surgical retractor or speculum having an improved functional configuration and further provided with means for illuminating the interior of a natural body cavity or a cavity formed by incision or a wound.

Abstract: A flow-through continuous countercurrent extraction system consisting of a coiled tube or spiral coplanar channel revolving around a main axis and rotating around its own axis at the same angular velocity and in the same direction. With two solvent phases A and B, there are 5 flow tubes: (1) a feed tube for phase B located at the head end of the column, (2) a return tube for phase A located at the head end, (3) a feed tube for phase A located at the tail end, (4) a return tube for phase B located at the tail end, and (5) a sample feed tube located at the middle portion of the column. The column is mounted on a hollow rotary shaft and the axis of revolution is defined by a stationary hollow central shaft. The 5 flow tubes are led through the hollow rotary shaft, and then through the stationary central shaft. In this way, the flow tubes from the rotary shaft are allowed to rotate freely without interference or twisting.

Abstract: A flow-through coil planet centrifuge mechanism with variable rotation-revolution (r/R) speed ratios, which does not employ rotating seals. The rotation and revolution rates are continuously adjustable by using separate variable-speed drive motors. A system of gearing and belts compensates for the rotation and revolution of the centrifuge column relative to a stationary supporting frame structure to avoid twisting of the flow tubes. A first motor drives a pair of spider assemblies arranged coaxially with a column-supporting spool. One spider assembly has planetary gearing cooperating with a fixed gear belt to rotate the column relative to the spool. The other spider assembly has planetary gearing driven by a second motor and coupled to the column support spool so that the spool revolves relative to the stationary frame structure and simultaneously the column rotates relative to the spool.

Abstract: A clot lysing timing device consisting of a thermostatically controlled assembly including heated blocks formed with wells to receive precooled test tubes containing liquid with clots formed by the addition of thrombin to plasma (or to a mixture of fibrinogen and plasminogen) containing varying quantities of urokinase, streptokinase or plasmin. The blocks are maintained at 37.degree. C. when a precooled test tube with such contents is placed in one of the 37.degree. C. wells it activates a microswitch which starts a corresponding timer channel. An opaque sphere is placed on top of the clot. As the clot dissolves (at a rate depending on the quantity of lytic agent incorporated in the clot) the sphere travels to the bottom of the test tube, interrupting an infra red light beam, which stops the corresponding timer channel. The time counts from the respective timer channels can be selectively displayed on an LED digital readout device.

Abstract: Seven-membered heterocyclic nucleosides used to inhibit the deamination enzyme responsible for the inactivation of arabinosylcytosine (ara--C). Preferred nucleosides containing a seven-member aglycone are as follows: ##STR1## Preferred aglycones are as follows: ##STR2## Active components utilized against pyrimidine deaminases from mammalian tissues (mouse kidney and human liver) showed optimum advantage when compared with tetrahydrouridine (THU).

Abstract: Analogs of 3'-phosphoadenosine 5'-phosphosulfate, also known as PAPS, are useful in establishing sulfate transfer mechanisms in animals and may be produced by a chemical process yielding an analog B of a pure adenosine 2',3'-cyclic phosphate 5'-phosphate, which compound is initially prepared from the reaction of adenosine and pyrophosphoryl chloride. In the present process an analog B is selected from 8-bromoadenine, purine, hypoxanthine, 4-aminopyrrolo[2,3-d]pyrimidine (tubercidin), and 7-amino-pyrazolopyrimidine (formycin). In the pilot procedure the pure cyclic phosphate is reacted with triethylamine-N-sulfonic acid to produce 2',3'-cyclic phosphate 5'-phosphosulfate. Subsequently, by hydrolysis with the enzyme ribonuclease-T.sub.2, the desired compound, an analog of PAPS, is produced. Alternatively, the 2'-phosphoadenosine 5'-phosphosulfate, known as iso-PAPS, may be produced from 2',3'-cyclic phosphate 5'-phosphosulfate by treatment with a different enzyme, PDase II or spleen phosphodiesterase.

Abstract: An artificial heart valve comprising a semi-rigid framework having three projecting symmetrical struts and open axially therethrough, as well as a polyurethane elastomeric membrane attached to the struts and constituting three leaflets, is formed by molding the framework, including the base and strut, using polyurethane resin; forming the elastomeric membrane, of polyurethane resin which is thin relative to the framework, and forming a thickened commissure along the leading edge of the membrane as well as reinforcing lines radiating from its base; then joining the framework with the elastomeric membrane using an adhesive cement so as to permanently bond the membrane to the framework.

Abstract: A cold stage for an electron microscope, said cold stage being arranged to reduce relative motion between the sample holder and the objective lens. The cold stage consists of an annular stainless steel body on which is coaxially bolted a plastic insulator ring with a plurality of spaced upstanding short vertical posts. A central arbor of gold-plated copper has outwardly projecting radial lugs engaged on and bolted to said posts. Connected to another radial lug projecting from the arbor is a laminated thermally conducting strap member consisting of 40 superposed thin flexible leaves of heat-softened copper, with a 180.degree. blend to absorb vibrations from the associated cold finger, or heat transfer rod, leading from a liquid nitrogen cooling source.

Abstract: In an elegant stepwise process for the production of intermediates of thromboxanes such as TXB.sub.2 from a chiral glucose starting material such as .alpha.-methylglucoside, those steps comprising: ##STR1## A key modification introduced in this synthetic sequence is the use of 4-dimethylaminopyridine for the selective alkylation of primary alcohols in the presence of unprotected secondary alcohols and for the controlled acylation of methylglucoside. The former application has large potential use in the synthesis of nucleosides, polynucleotides, and carbohydrate derivatives.

Abstract: A single-lumen, one piece catheter approximately 0.04 inch in diameter with an integral balloon at its end having a wall thickness of 0.005 inch or less, sufficiently small to be retractible by suction into the catheter and to be extensible at a desired site by fluid pressure. The balloon may have a calibrated restricted leak aperture. The balloon portion of the catheter is made by heating a portion of the catheter tubing, stretching the tubing lengthwise, and applying fluid pressure to the tubing. The apparatus for forming the balloon includes a spring-loaded clamp to hold the tubing at one end, a capstan to hold the tubing at the other end, a heating coil wrapped around the tubing near the clamped end thereof and mounted with the clamp, and a mechanism for controlling the pressure and volume of the pressurizing gas entering the lumen of the tube in accordance with the retractile movement of the spring-loaded clamp.

Abstract: Homocysteine thiolactone perchlorate is prepared from the corresponding homocysteine thiolactone hydrochloride and optimally about two equivalents of perchloric acid as reactants. A preferred solvent utilized is chloroform-methanol (4:1) solution and a preferred temperature range is 0.degree.-85.degree. C. with the lower limit dependent upon the particular solvent and the upper limit of about 186.degree. C. dependent upon the melting point of the product crystals. The preferred perchloric acid reactant may be replaced with perchlorate salts such as AgClO.sub.4 or KClO.sub.4. The product perchlorate salt is soluble in organic solvents, whereas other known salts such as the hydrochloride are only water soluble. This property is thought to influence the growth effect of the perchlorate salt in animals, such as rabbits, and to influence the unique effect of the perchlorate salt on the growth of malignant tumors in animals, such as mice.

Abstract: A finger tip sensitivity-testing instrument consisting of a tunnel-shaped track member used as a support for the hand and forearm of a patient, the track member having a longitudinal cavity slidably receiving a feeler bar which is formed on its top surface with surface profile structure varying progressively longitudinally in sensible magnitude. The patient's finger is received in a notch in the edge of the tunnel top wall so as to allow the finger to engage the surface profile bar as it is extended from the tunnel. Graduations are inscribed along the side margin of the feeler bar which represent specific increments of differential surface profile relative to the mouth of the tunnel. The feeler bar rests slidably on a spring-supported plastic thin plate, thus simulating a floating support surface for the feeler bar.

Abstract: Laboratory apparatus for cloning mammalian cells includes a support plate and a plurality of tubular cylinders fixedly secured within the plate and projecting from one face thereof. All of the cylinders, with the exception of one pair, are disposed within a concentrated array defined within a predetermined sector region of the plate, the remaining pair of cylinders being located remote from the sector array yet equidistantly spaced from each other and from the sector array so as to complete the distribution pattern. A substantially C-shaped ring member is fixedly secured to, or integrally formed with, the opposite face of the support plate, in order to facilitate maneuverability of the assemblage when placing the same onto a Petri dish for isolating the colonies developing thereon. The plate and ring member are fabricated from transparent polycarbonate in order to permit the colonies to be identified or viewed by background lighting techniques.

Abstract: A system for reproducibly aiming an X-ray source array to provide substantial registration of exposure geometry through an organ or a portion of tissue from one examination to the next. The system derives functions or signals based on computer controlled X-ray source point geometries to create multiple images produced from known positions via a detector array which feeds this information to a computer image storage system and which provides for comparison of the detected signals with reference signals originally stored in a memory; the comparison yields correction signals which act to shift the X-ray raster toward restoration of the original effective geometry.

Abstract: A dual-energy detector system for use in computer assisted tomography. This system produces two independent sets of information from one scan, namely, high-energy and low-energy data. The system employs two cooperating detectors. The first one responds primarily to low-energy photons, allowing most high-energy photons to pass through. The second detector lies behind the first and detects the remaining photons. Thus, two electrical signals are generated which contain information in two different energy ranges, which signals can be computer-processed. The attenuation coefficients at these two energies are sufficiently different so that differential diagnosis and chemical identification may be aided. The computer-processed signals may be employed to provide any of (a) beam-hardening correction, (b) chemical identification and composition of tissues, such as lesions, bone, etc., (c) localization of injected contrast material, or (d) attenuation coefficients for radiation therapy planning.

Abstract: Steroidal cyclotriphosphazenes of the formula ##STR1## wherein R is the residue of a 3- or 17-hydroxysteroid and R.sub.2 is alkyl, are hydrolytically labile compounds adapted for slow release in vivo of active steroidal compounds of the formula ROH.

Abstract: An apparatus for the continuous production of high-purity water includes a distillation flask, a carboy and a condenser unit, all of borosilicate glass. A respective filter, preferably in the form of a polytetrafluoroethylene sheet, is provided between the ambient atmosphere and the interiors of the flask, the carboy and the condenser unit to remove airborne bacteria and dust particles. An inlet valve is provided for feeding water to be purified into the flask, all water-contacting parts of this valve being of polytetrafluoroethylene. The open parts are interconnected with flexible, polytetrafluoroethylene tubing. A two-way, stopcock allows high-purity water to be removed from the carboy. The flask is provided with a glass overflow trap. In one variant, the water is fed into the flask via members between the trap and the flask.

Abstract: A horizontal flow-through coil planet centrifuge wherein flow-through separation columns are rotatably mounted on both sides of a rotor formed by a pair of spaced parallel rotary wings, with suitable intercoupling to avoid the need for rotary seals. Fluid circuit and adjustable valving arrangements are provided for (1) allowing two separations to be simultaneously performed, (2) for connecting the two columns in series to double the partition efficiency, or (3) using one column to separate samples in an ordinary manner while a desired portion of the eluate can be introduced into the second column to recycle.