Beckman Coulter COULTER LH 750 System, Справочник

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PN 4277248DD
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USE AND FUNCTION
METHOD HISTORY
by size.
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Electronic refinements in the Model S-PLUS enhanced the accuracy of the
hydrodynamic method. Von Behrens and Paulus have also cited the feasibility of counting
thrombocytes by the Coulter method.
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Corrected WBC Counts
White Blood Cell count results from the CBC analysis. The WBC count may be adjusted for
interfering substances when appropriate. If there is a population of cells in the far left of the
WBC histogram, the number of cells is derived and the WBC count is corrected. No further
correction of WBC is required.
Figure 1.2 Corrected WBC
When WBC correction has occurred, the uncorrected WBC will appear in the printout
Comments field as UWBC = "value". The "Cellular Interference" suspect message is
displayed and the corrected WBC count is reported. The uncorrected WBC can be found on
the CBC data tab. When the separation between the WBC populations is poorly defined on
the histogram, WBC correction will be performed and the corrected WBC will have an R flag.
Hemoglobinometry
The lytic reagent used for the complete blood count (CBC) parameters prepares the blood so
the system can count leukocytes and measure the amount of hemoglobin. The lytic reagent
rapidly and simultaneously destroys the erythrocytes and converts a substantial proportion of
the hemoglobin to a stable pigment while it leaves leukocyte nuclei intact. The absorbance of
the pigment is directly proportional to the hemoglobin concentration of the sample.
The accuracy of this method equals that of the hemiglobincyanide method, the reference
method of choice for hemoglobinometry recommended by the International Committee for
Standardization in Hematology.
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Differential Measurement
The COULTER VCS established WBC differential technology using three measurements:
individual cell volume, high-frequency conductivity and laser-light scatter.
The combination of low-frequency current, high-frequency current and light-scattering
technology provides abundant cell-by-cell information that is translated by the instrument
into conventional stained-film leukocyte categories.
Volume Analysis
Electronic leukocyte volume analysis, using low-frequency current, has been used since 1967.
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It has been evaluated as a possible adjunct to the differential white cell count.
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