Abstract: A flow cell for a particle analyzer using an electrical sensing zone method, includes: a detecting member having a through hole; a first cell for supplying a particle containing liquid to the through hole; a second cell for receiving and discharging the particle containing liquid that has passed through the through hole; electrodes provided in the first cell and the second cell respectively, for supplying an electrical current to the liquid passing through the through hole; and a sliding member for sliding at least one of the first and second cells to change a distance therebetween; wherein the first and second cells cooperate with the sliding member to detachably sandwich the detecting member therebetween so that the detecting member is connected to the first and second cells in a watertight state.

Abstract: A particle detector includes: a flow cell having two chambers (A) and (B) communicating with each other via a through-hole, the chamber (A) having an inlet for a sheath liquid and the chamber (B) having an outlet for a waste liquid; a sheath liquid supplier; a nozzle for ejecting a particle-containing specimen with a tip portion of the nozzle being disposed at an appropriate position in the chamber (A), the nozzle being disposed coaxially with the flow cell and movable in an axial direction; an air cylinder for reciprocating the nozzle in the axial direction so as to switch between a sheath flow state for allowing the specimen and the sheath liquid to flow through the through-hole and a non sheath flow state for allowing only the specimen to flow through the through-hole; and a pair of electrodes for detecting a particle in the specimen when the specimen passes through the through-hole. Also, a particle analyzing apparatus including the particle detector is disclosed.

Abstract: The particle measuring apparatus includes a specimen pipetting section for pipetting a specimen liquid, a reagent dispensing section for dispensing a reagent, a mixing section for receiving the specimen liquid supplied by the specimen pipetting section and the reagent dispensed by the reagent dispensing section and a flow cell for receiving the specimen liquid and the reagent transferred from the mixing section and measuring particles therein; the pipet being so constructed as to be positioned in a first state of picking up the specimen liquid as well as in a second state of supplying the specimen liquid into the mixing section, the mixing section being open when the pipet is in the first state, the mixing section being kept closed by the pipet in the second state so that the reagent dispensed by the reagent dispensing section can press and transfer the specimen liquid in the mixing section out toward the particle measuring section.

Abstract: A method which comprises using a specified dye taken up by erythrocytic nucleated cells so that their nuclei are stained and can be readily differentiated from other cells by measurement with a flow cytometer is disclosed. The method relies basically upon flow cytometry by two-step staining that uses a first fluid that is an acidic hypotensive fluorescent dye solution and a second fluid that is a solution that changes the osmorality and pH of the first fluid. The first fluid further contains a fluorescent dye that diffuses into erythroblasts to specifically stain their nuclei, and a group of erythroblasts is separated from other cell groups on the two-dimensional plot constructed with the flow cytometer, whereby the results of erythroblast differentiation are computed.

Abstract: A blood sample is prepared by combining a fluorescently tagged monoclonal antibody with blood cells. The sample is then passed through a flow cytometer and light scattered by each blood cell in two directions is sensed simultaneously by a single sensor. Lymphocytes are discriminated from other cells by using an intensity distribution of the total scattered light. Then, by using a distribution of fluorescent light intensity of each cell thus discriminated, the cells in a lymphocyte subclass of interest are enumerated with a high accuracy. The data acquired are utilized in diagnosing immunological incompetence or the like.