Abstract: The filtering apparatus is used in combination with at least one analytical instrument, especially a particle analyzer and substantially comprises a controlled pump unit having an inlet side and an outlet side. The inlet side of the controlled pump unit is connected to a reservoir for a liquid medium to be filtered. The outlet side is connected to a filtering unit. An intermediate storage unit for intermediately storing the filtered liquid medium is connected to the filtering unit. The filtered liquid medium is fed to the analytical instrument from the intermediate storage unit which contains level detectors for detecting the liquid level in the intermediate storage unit. The level detectors are connected to a control unit for controlling the controlled pump unit.

Abstract: The apparatus for analyzing particles in a particle containing fluid, especially pretreated liquids containing blood samples, contains storage devices and computing sections for determining separation threshold values and the particle distribution as a function of a pretermined particle parameter. The separation threshold values are determined on the basis of measured values of the predetermined particle parameter arranged in individual histograms containing at least two particle population maxima and minima. At least one particle population minimum is determined using an adaptive method. For insufficiently distinct particle population minima, there is first determined, on the basis of histograms containing corresponding distinct particle population minima and maxima, a characteristic difference quotient: ##EQU1## The separation threshold value associated with the insufficiently distinct particle population minimum is determined on the basis of the characteristic difference quotient according to:S.sub.

Abstract: An injection syringe is disclosed which comprises a cylinder equipped at one end with an attachment flange and at the other end, near to an outlet or discharge opening thereof, with a catheter connection. A piston member is insertable into the cylinder, and a container or receptacle is located between the piston member and the outlet or discharge opening. The container is provided with reference fracture locations and is freely displaceable within the cylinder in the lengthwise direction thereof. This container is filled with one of two liquids. After the ejection of the other liquid located within the cylinder externally of the container the container splits open and releases the injection the liquid contained therein. The injection syringe can be used, for instance, for the injection of a contrast agent followed by flushing with a physiological saline or salt solution, but also can be used in all other fields of application where it is desired to apply in timewise succession two liquids.

Abstract: A sensor syringe or hollow needle arrangement for the automatic withdrawal of a liquid sample from a liquid contained within a vessel. A duct is enclosed in a sheath or jacket-like manner by a light conductor possessing an inlet for an optical source and an outlet leading to an optical detector. During sample withdrawal there is utilized the change in the reflection behavior of the lower end of the light conductor upon its immersion in the liquid in order to control sample withdrawal.