Abstract: Apparatus and method for modeling of thrombogenesis using haemostasis measuring devices. A sleeve member is provided on a blood-carrying tube to simulate an environment of a human artery. When punctured with a small needle, bleeding is simulated, permitting blood to be trapped between the sleeve and blood-carrying tube. The trapped blood communicates with the blood flowing in the tube, resulting in thrombus formation.

Abstract: A measurement device is provided for determining relative proportions of at least two materials forming a liquid and having different densities and different responses to light. A transparent capillary size cuvette tube confines the sample liquid, and is attached radially on a rotor wheel, preferably by a holder which seals an outer end of the tube and provides a package for manipulation of the tube without exposure to the sample. A motor controlled by a processor turns the rotor wheel, separating the materials by their densities. A linear light source illuminates the tube, and a linear array of photosensors defining pixels produces a signal which varies where the different materials abut. The pixels are counted, to locate the stratum between materials and the result is displayed as a percentage of total volume, suitable for hematocrit measurements. The cuvette tube has a fin for assisting in manipulation, is shaped as an elongated lens, and is cut to a spherical end surface to assist in sample collection.

Abstract: A blood extracting and receiving container assembly (10) having a coating agent (22) disposed on an interior surface of a blood receiving chamber (12) and an extracting apparatus (14) to effectively isolate a blood specimen from contacting surfaces which would initiate clotting. The coating agent contains molecules which inhibit the activation of blood elements responsible for initiating blood clotting processes. A method for manipulating a blood specimen in vitro in association with the subject blood extracting and receiving assembly (10) includes the steps of coating an interior surface of the extracting and receiving container assembly (10) with nonthrombogenic coating agent (22), and, while coating agent (22) adheres to the interior surface of assembly (10), withdrawing a blood specimen (24) into the assembly.

Abstract: The invention relates to a method for the functional determination of von Willebrand factor by determination of the sedimentation rate of platelets in the presence of ristocetin during centrifugation.

Abstract: Tissue damage may be quantified, tissue type identified, neural activity monitored or blood hematocrit determined by measuring the difference between the total tissue sodium and potassium concentrations in the area in question. Comparison of these measurements with standard values permit evaluation of the amount of tissue damage in cells of the same type or the tissue type in non-necrotic cells. Evaluation over time of normal brain cells permit monitoring of neural activity. By directly and simultaneously measuring sodium and potassium ion concentrations, for example, a nuclear magnetic resonance spectrometer can image areas of different tissue type in differing colors. In this manner tumors and lesions can be clearly delineated. Measurement of total potassium concentration of a blood sample and the potassium concentration of the cell-free plasma will permit determination of cellular volume fraction (hematocrit).

Abstract: Quantification of blood plasma fibrinogen content is made in a sample of anticoagulated whole blood contained in a sampling tube. The tube is a transparent centrifuge tube which contains a sample constituent layer-elongating float. The blood sample is centrifuged in the tube containing the float, and various cell constituent measurements are made. The centrifuged sample is then heated and recentrifuged to cause the precipitated fibrinogen to layer out on top of the float remote from the buffy coat band in the plasma layer. The thickness of the fibrinogen band is then measured, whereby quantification of the fibrinogen content of the blood sample can be made by a precalibrated instrument.

Abstract: Blood constituents are separated by centrifugation in a transparent tube which contains a float for physically elongating certain of the constituents. The centrifuged sample in the tube is positioned on a layer measuring device with which red cell and buffy coat constituent band heights can be measured in ambient light. The buffy coat constituent measurements are made under optical magnification. The measuring device has a mathematically derived red cell layer nomogram printed thereon, and a separate scale for measuring buffy coat constituent bands. Conversion tables are provided for converting the measured buffy coat constituent band lengths into constituent cell counts. The measuring device includes tube-engaging portions for properly positioning the tube during the measurements, and the red cell scale automatically compensates for the presence of the float and densification of red cells needed for proper banding.

Abstract: A disposable blood holding cassette for haemostatic measurements. A single unit is provided having a blood sample container with three separate pressurized blood sample reservoirs. A waste blood collection reservoir is connected to the blood sample container, and connected thereto via first, second and third blood sample tubes. A punching station is provided to accurately punch first and second of the blood sample tubes, simulating haemostasis function in vitro. Measurements may be made of the haemostatic and thrombolytic function of recently sampled blood. The entire device is disposable, isolating any contaminated blood from clinical personnel.

Abstract: In a pipe 1 for measuring erythrocyte sedimentation rate, a sealing plug body 3, made of synthetic resin material which passes air but swells when water is absorbed thereby, is inserted into the pipe 1 in such a manner that the lower surface of the plug body 3 may be brought into contact with zero graduation of the pipe 1. The pipe is disposable, and it is possible to measure erythrocyte sedimentation rates easily and at small expense.

Abstract: A dry analysis element for determination of a particular constituent in erythrocyte-containing blood, which comprises at least a water permeable porous spreading layer and a water permeable reagent layer arranged on the side opposite to the liquid accepting face of the porous spreading layer, and which contains a reagent composition capable of producing an optically detectable substance in the presence of an analyte in at least either of the water permeable layers. The porous spreading layer contains cholic acid, deoxycholic acid or salts thereof to enable accurate determination of the constituents in whole blood, irrespective of the hematocrit value.

Abstract: During an initial priming procedure, the blood draw/return needle(s) fluid flow system is primed with a nonblood fluid (e.g. a saline solution) having known fluid viscosity. The pressure drop occurring across the needle orifice(s) is determined at a knonw flow rate for this predetermined fluid of known viscosity. During subsequent blood constitutent processing operations, the pressure drop across the needle orifice is measured for a second known flow rate of blood constituents. From these measured relative values of pressure and flow rates, the blood viscosity value can be calculated and used to estimate (e.g. via a table look-up or analytical calculation procedure) a hematocrit value of the blood constitutents as a function of the measured blood viscosity value.

Abstract: An arrangement for determining the blood cell sedimentation rate, comprising a pipette having at the upper end thereof a levelling device; a tube and a plunger sealingly engaging the outside wall of the pipette and having a diameter generally the same as the inside diameter (d) of the tube. The plunger is inserted in the tube at a distance from the lower end of the pipette such that when the plunger is inserted in the tube until such lower end of the pipette abuts the bottom end of the tube, it displaces blood into the pipette capable of filling the pipette without overflowing from the ensemble formed by the pipette plus the levelling device.

Abstract: A method and apparatus for adsorption and detection of adsorbents or analytes. The method and apparatus can be employed in the field for rapid adsorption of analytes and is particularly useful for detection of mycotoxins. A sample to be analyzed is prepared in solution and placed in a test tube. A tube-like adsorption column having a seal and a valve member is forcefully fed into the test tube to force solutions through the valve member into the column and through a filter and adsorbent to trap interference. The semi-purified solution may then be analyzed for the presence of analytes. The column with the purified solution may be further employed with a second smaller adsorption column similarly equipped with a seal and valve member fitting within the first column. In similar fashion the second column may be forced into the first column to expel the solution therein into the second column and through one or more selective adsorbents for different analytes such as one or more mycotixins.

Abstract: This invention is a semiautomatic hematocrit reader apparatus and method. A microhematocrit capillary tube is positioned under a movable cursor which is then moved along the length of the microhematocrit capillary tube. A switch is depressed to make a data entry at predetermined points along the length of a blood/plasma sample in the microhematocrit capillary tube. The relative distances travelled across the packed cell volume versus the plasma is electronically calculated and displayed automatically.

Abstract: A whole blood sample is placed in a tube such as a capillary tube, with a plastic float. The float is axially elongated and has a specific gravity which causes it to float in the packed red blood cells when the sample is centrifuged in the tube. The hemoglobin concentration of the packed red blood cells is measured by measuring the depth that the float sinks into the red cell layer, and then the hemoglobin concentration of the blood is calculated. The hemoglobin can be measured in this manner because virtually the only red cell component which contributes density to the red cells is the hemoglobin. The hemoglobin concentration of the whole blood is calculated by multiplying the mean corpuscular hemoglobin concentration of the packed red blood cells by the packed cell volume % (hematocrit) of the whole blood. All of the necessary calculations may be performed by a preprogrammed microprocessor.

Abstract: There is described a method and apparatus for the determination of hematocrit levels in which both the conductivity of whole blood and the conductivity of blood plasma are determined together. While a conductivity cell (18) is being used for the determination of the conductivity of whole blood, the conductivity of plasma is calculated in a computer (30) with the aid of ion selective electrodes (14, 16) from the sodium or potassium concentrations.

Abstract: A historical time series analysis is obtained from a single sample of blood by measurement of hemoglobin and an altered hemoglobin, for example, glycohemoglobin, on a cell-by-cell basis. The results are compared by ratio of glycohemoglobin to hemoglobin on a cell-by-cell basis. Since the alteration of hemoglobin is continuous and irreversible, the ordered set of ratios represents a time-series of the cells, and any deviation from normal will be readily apparent A time-series can also be derived for other constituents, the time-series representing historical data of the other constituents in the person from whom the blood sample was taken.

Abstract: A whole blood aggregometer of red blood cells (RBC) consists of a transparent tube containing freshly drawn heparinized blood, and a densitometer head which is attached to the tube. The densitometer head consists of a light source and a light detector to monitor changes in optical density of the blood in the tube. The blood in the tube is first subjected to rapid flow with a solenoid, so that the wall shear rate of the blood approximates to 500 s.sup.-1. The shear gives rise to a rapid increase in optical density of the blood due to dispersion of the blood corpuscles. The blood is then brought abruptly to a full stop. After the flow has stopped, the densitometer head reveals a gradual decrease in optical density in association with RBC aggregate formation. The resultant pattern is termed as an "RBC aggregogram". The RBC aggregogram exhibits a quasi-exponential decay in its initial part, which is followed by an asymptotical decrease.

Abstract: The present invention relates to a method for making liquid analysis and to an analytical element to be used in the method. The method is especially suitable for analysing organic fluids, like blood. The analytical element is of the integrated element type and consists of two parts of certain volume, which parts are connected to each other so that they form a pair of communicating vessels. In the preferred embodiment the element consists of two arms, one is a descending arm and the other is an ascending arm. There is a liquid carrier phase in the end of the descending arm and said phase is dipped into the liquid to be analysed for dosing the liquid in a quantitative manner. An external gravitational field like a centrifugal force is used to move the liquid inside the element through a diffusion zone and a reaction zone to a detection zone for the measurement of the result.

Abstract: The apparatus consists of at least one test-tube carrier defining seats for test tubes. The carrier is moved by oscillation or rotary motion about a horizontal axis under the influence of time control means. A structure which is vertically movable relative to the test tubes is fitted with individual means for the photometric observation of the data relating to each test tube and is controlled by time-control means. Processing and recording means collect data relating to the presence of each test tube, the presence of a sample, and the level of said sample, for each test tube seat.

Abstract: A method of neutralizing the electrostatic forces in liquids or solutions in liquid phase, preferably blood and blood solutions, respectively. The electrostatic forces primarily consist of surface tension and interrepellant forces between particles in the solution.The purpose of the invention is obtained by adding polypropylene glycol H[OCH(CH.sub.3)CH.sub.2 ].sub.n OH to the liquid or solution. Polypropylene glycol possesses properties allowing it to neutralize the electrostatic forces without affecting the red blood cells.

Abstract: A device for sampling blood and measuring erythrocyte sedimentation rate. The device comprises a tube with one end closed, a blood sampling portion on an opened end of the tube and an erythrocyte sedimentation rate measuring portion extending from the blood sampling portion. A stopper is located on the open end of said tube, and may be pierced with a blood drawing needle. Finally a partition member is located within said tube and extends substantially over the entire length of said tube. Blood is directly sampled into the device and the device mixes the sampled blood with a solution of an anticoagulant with a high efficiency in the device. Accordingly, measurement of erythrocyte sedimentation rate can be performed quickly and easily.

Abstract: A method for measuring hematocrit is provided. An electrochemically detectable marker is measured before and after the ratio of red cell volume to plasma volume is decreased. The measured concentrations are used in a mathematical formula to determine hematocrit value.

Abstract: Partial thromboplastin time (PTT) is determined for monitoring and controlling heparin therapy with a test kit having increased sensitivity to heparin. Increased sensitivity is obtained by including with reagents in the test kit an organic sulfuric acid or salt thereof such as dodecylbenzenesulfuric acid--sodium salt and/or an organic sulfuric acid ester or salt thereof such as sodium laurylsulfate.

Abstract: A method for determining allergenic sensitivity of a mammal is disclosed. The method involves measuring the time required for hemostasis of a blood sample with an allergen in the presence of a blood clotting inhibitor and comparing the time required for hemostasis in the presence of a blood clotting inhibitor and the absence of the allergen. The sensitivity to the allergen is determined by determining the difference in time required for hemostasis.

Abstract: A method for measuring hematocrit is provided. An electrochemically detectable marker is measured before and after the ratio of red cell volume to plasma volume is decreased. The measured concentrations are used in a mathematical formula to determine hematocrit value.

Abstract: Apparatus for determining sedimentation rates including a first support means having a plurality of tubes, held vertically and spaced, and a second support means having a plurality of tubes, of larger diameter than the tubes mounted on the first support means, and each able to receive a blood sample, the tubes being vertical and spaced on the said second support means, and a single suction device mounted at the upper end of the first support means, the support means being movable with respect to each other between a first position in which the tubes of the first support means are separated from the tubes of the second support means, a second position in which the lower ends of the tubes of the first support means dip into the tubes of the second support means, and a third position in which the sedimentation of the red blood corpuscles takes place.

Abstract: A complex liquid, such as a biological liquid, is stratified, as by centrifugation in a tube, into constituent layers. The most dense or heaviest constituent layer is measured volumetrically by physically expanding the entire layer with a cylindrical float which is inserted in the tube and which occupies the portion of the tube also occupied by the constituent layer being measured. The axial extent of the expanded layer is measured to provide an indication of the volume of the layer being measured. The end of the tube proximate to the layer being measured contains a plug of a more dense material which is immiscible with the subject liquid and into which the float will settle during centrifugation. The float thus settles into the plug of dense material and "floats" therein so as to extend through the entirety of the layer being measured.

Abstract: An apparatus for blood analysis to determine the rate of corpuscle sedimentation. The apparatus has a first support (1) with several graduated tubes (4) open at both ends and held vertically in spaced relation on the first support. The tubes (4) have enlarged lower ends (4b) which can diverge. A second support (2) has blood sample containers (13) of larger diameter than the vertical tubes on the first support. The containers (13) are spaced apart on the said second support, the same distance as the tubes on the first support so the containers are respectively, vertically below the tubes. Sealing and flow inducing members engage in the diverging lower ends (4b) of the respective tubes. The support means (1, 2) are movable with respect to each other between a first position in which the tubes are vertically above the containers, and a second position in which the lower ends of the tubes are immersed in the containers.

Abstract: A method and means for measuring erythrocyte deformability is provided comprising an absorbent strip and a filter membrane, the membrane characterized by pores having a mean pore size in the range of 3.0 to 8.0 microns, the membrane and the strip being in at least partial cofacial contact. A 10 microliter sample of blood is drawn through the membrane by capillary action and flows along the absorbent strip. The time required for the blood to traverse a predetermined lateral distance along the strip is recorded.

Abstract: In a time-marking sedimentation process where two or more fractions in a sample containing liquid are to be separated entirely or partially by their specific weights in a tube or corresponding structure, a plug (2) of a hydrophilic plastic substance is brought into contact with the sample. The plug (2) has original dimensions smaller than the inner diameter of the tube (1) and has a specific weight lying between the specific weights of the fractions. The plug is adjusted with respect to its dimensions and/or substance so as to attain a swelling degree sufficient for the plug to jam in the tube (1), to mark the separation line between the fractions (3,4) after a certain predetermined period. Thereafter the position of the plug (2) in the tube is read. The method and device are particularly advantageous in medical connections, especially in the determination of the sedimentation reaction of blood, in which blood corpuscles are separated from plasma.