초록 ▼

A blood clotting end point detector which includes means for monitoring an electrical signal representing the value A of one or more optical properties of a blood plasma sample to which a coagulating agent has been added, means for deriving the first and the second differentials with respect to time

A blood clotting end point detector which includes means for monitoring an electrical signal representing the value A of one or more optical properties of a blood plasma sample to which a coagulating agent has been added, means for deriving the first and the second differentials with respect to time of the value A, means for detecting the moment Ta when the second differential changes from negative to positive or becomes positive, means for detecting the moment Tb when the second differential next changes from positive to negative, means for deriving the difference (R) between the tangent to the curve A at the moment Ta and the curve A, means for determining whether the difference (R) or the integral, with respect to time from moment Ta to moment Tb, of the difference (R) exceeds a predetermined threshold value, in which case moment Tb is taken as the true clotting end point.

대표청구항 ▼

A method of detecting the blood clotting end point of a blood plasma sample to which a coagulating agent has been added, which includes: monitoring an electrical signal representing the value A of one or more optical properties of the sample, substantially continuously deriving the first and second

A method of detecting the blood clotting end point of a blood plasma sample to which a coagulating agent has been added, which includes: monitoring an electrical signal representing the value A of one or more optical properties of the sample, substantially continuously deriving the first and second differentials with respect to time of the electrical signals representing the value A, detecting the moment Ta when the second differential changes from negative to positive or becomes positive, detecting the moment Tb when the second differential next changes from positive to negative, and identifying the moment Tb as the true clotting end point only if at least one of the following two conditions are satisfied: (i) the difference (R) between the tangent to the electrical signals representing the value A at moment Ta and the value of said value A signals exceeds a first predetermined threshold value; and (ii) the integral, with respect to time from the moment Ta to the moment Tb, of said difference (R) exceeds a second predetermined threshold value.