Abstract: Reference controls comprised of aldehyde-fixed white blood cells exhibiting a white blood cell histogram profile that is substantially that of whole blood are obtained by the additions of a lipoprotein to the control.

Abstract: A tissue fixative solution and method is disclosed which comprises a histological fixing composition of diazolidinyl urea, 2-bromo-2-nitropropane-1,3-diol and a water-soluble zinc salt such as zinc sulfate dissolved in a solvent such as water, alcohol or dimethylsulfoxide. The fixative solution of the invention is much less toxic than prior art fixatives and thus can be used more safely, conveniently and effectively than previous solutions in histological techniques. In addition, the fixative solution allows good tissue preservation to be obtained, and because tissue antigens are retained, the fixative is useful for all types of immunostaining procedures.

Abstract: A new method for separation of white cells in differential hematology instruments is described. In the method described, white cell shrinkage is controlled by the use of diazolidinyl urea and accelerated with alcohol thereby providing a reproducible method for easy manipulation of the white cells. In addition, it was found that adsorption of blood platelets and red blood cells in the instruments can be prevented by use of a surfactant such as the polyols.

Abstract: Tissue fixatives, such as diazolidinyl urea, which are free of aldehydes and toxic chemicals are described. When used, either in aqueous or alcoholic solutions, good tissue preservation is attained. In addition, tissue antigens are retained which makes the fixative useful for immunostaining procedures.

Abstract: Lysable, blood platelet controls are prepared by treating animal red blood cells larger than or within the size range of human blood platelets with a fixing agent for red blood cells for a time sufficient to partially rigidify the red blood cell membrane enabling shrinking to a permanently shrunk condition, subjecting distinct groups of said partially fixed red blood cells to hemolysis wiht a hemolytic agent to partially remove hemoglobin therefrom, the hemolysis of each distinct group of cells removing a different amount of hemoglobin, subjecting the resulting red blood cells to centrifugation to collapse the red blood cell membrane around the hemoglobin remaining in said cells, said distinct group of cells and the extent of hemolysis being selected so as to provide after said centrifugation a mixture of permanently shrunken lysable cells that simulate in number, size and volume distribution the platelets present in human whole blood.

Abstract: A temperature measuring apparatus includes a tubular bulb thermometer disposed in a receptacle having a liquid isothermal bath therein. The bulb of the thermometer is sealed in the receptacle and a transparent cover member surrounds the receptacle and thermometer to protect the receptacle and thermometer. However, if breakage does occur, the cover member prevents any leakage or pieces of the thermometer or receptacle outside of the cover member. A U-shaped bracket having a magnet thereon is used to attach the cover member to a vertical wall as well as to space the cover member from the wall.

Abstract: A platelet aggregation reagent for EDTA-anticoagulated blood comprises calcium chloride, sodium citrate and a platelet-aggregating agent; the calcium chloride and the sodium citrate being present in a proportion of about 1.5 micromoles: 5 micromoles to about 7.5 micromoles: 2.5 micromoles per at least about a platelet aggregating amount of the agent.A platelet aggregation reagent container for EDTA-anticoagulated blood comprises an elongated container suitable for use in a platelet counter containing a reagent comprising about 1.5 micromoles to 7.5 micromoles of calcium chloride, about 2.5 micromoles to 5.0 micromoles of sodium citrate, and at least about a platelet aggregating amount of a platelet aggregating agent.

Abstract: A stable glucose reference control has been found in which the true value and the measured value of glucose in blood, colorimetrically obtained with glucose test strips, is approximately the same. The glucose reference control comprises an aqueous suspension of:(i) 40 to 500 mg/dL of glucose, and(ii) about 0.1 to 0.3.times.10.sup.12 /dL red blood cells fixed with a fixing agent to render the red blood cells incapable of metabolizing glucose.

Abstract: A lysable, blood platelet reference control comprising a suspension of a mixture of permanently shrunken animal red blood cells in a suspension medium non-deleterious to said cells, said cells having been partially fixed with a fixing agent to reduce cell membrane elasticity prior to being shrunken, and said mixture of permanently shrunken cells in said suspension medium simulating in number, size and volume distribution the platelets present in human whole blood.

Abstract: A platelet reference control and method of preparation in which a minor amount of solid polyethylene glycol is added either to the platelet suspension or the diluent for the platelet suspension whereby time and agitation stabilization are both achieved.

Abstract: A laboratory testing procedure wherein test tubes are uniquely supported under conditions of refrigeration, the test tubes being placed in a generally vertical position with only the test tube bottom portions in contact with the top surfaces of a closed refrigerant reservoir having heat-absorbing means confined therein.