Beckman Coulter COULTER LH 750 System, Справочник

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PN 4277248DD
3-9
OPERATION PRINCIPLES
COUNTING AND SIZING
3
The Manual mode of operation is like the Automatic mode except:
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Before you run the sample, you enter the sample identification number by performing
any of the following--
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Scanning the bar-code label on the tube
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Entering the ID number on the Numeric Keypad
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Entering the ID number in the bar-code field on the LH Workstation from its
keyboard.
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You use an open vial and introduce the sample at the aspirator tip.
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You begin the cycle by obstructing the optical sensor’s beam
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The system aspirates a maximum of 200 µL of sample.
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The blood detectors are not active in the Manual mode.
3.4 COUNTING AND SIZING
Red and White Blood Cell Counting
The RBC and WBC baths each have three discrete apertures that function as independent
systems. The six aperture currents are individually adjusted during calibration. When the
Aperture Current/Signal Generator (API-SIG GEN) card applies current to the apertures,
there is a delay. During this delay, the system conditions the electronics to perform the
counting and sizing of the sample.
Regulated vacuum draws a precise volume of sample dilution through the apertures. At each
aperture, the system gathers pulses for 4 seconds. The RED/WHITE PRE-AMP cards amplify
these pulses and the Analyzer screen displays them.
The system sends these pulses to the RED/WHITE PROCESSOR card. The RED/WHITE
PROCESSOR card counts and sizes the RBC and WBC data. The RBC and WBC raw data
consists of counts, wait time counts, count time, and channelyze time, as well as histograms
for each of the three apertures The Analyzer then sends the raw data to the workstation.
The workstation then:
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Corrects the RBC and WBC raw counts for wait time and coincidence.
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Fit the PLT histogram and corrects the PLT histogram count for coincidence.
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Calculates HGB from the blank and sample readings.
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Scales for calibration and dilution.
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Performs voting on the three apertures for RBC, WBC, PLT.
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Derives the parameters from the RBC histogram; MCV and RDW.
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Derives the MPV and @PDW parameters from the Plt histogram and @Pct and @PDW.
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Derives the calculated parameters.
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Displays results and histograms.