horiba ABX MICROS ES60, Руководство пользователя

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ABX Micros ES60 OT/CT
3–10 User Manual - RAB237AEN
3.3.8. PDW
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The PDW (Platelet Distribution Width) is calculated from the platelet histogram/distribution
curve.
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The PDW is represented by the width of the curve between 15% of the number of platelets starting
from the low threshold 2fl (S1) and 15% of the number of platelets begining with the variable
high threshold (S2). The PDW determination area is shown by the distribution curve below.
3.3.9. WBC
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The WBC measurement principles are based upon the same as the RBC/PLT measuring principles.
The WBC count is performed in the WBC/HGB chamber. The electronic signal processing device
places an electronic threshold between the WBCs and the PLTs. The electronic pulses are then
placed into 256 channels according to pulse size. The pulses are then thresholded, grouped, then
mathematically calculated to create a numerical value for the determination of WBCs.
WBC histogram
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The WBC histogram is a distribution study that reveals the following 3 types of white blood cell
sub-populations: lymphocytes, monocytes and granulocytes. The diluent and lyse of the ABX
Micros
ES60 OT/CT play a very important part when sizing the WBC subpopulations in the WBC
distribution curve.
Differential measuring principles
Diluent and lysing action
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The diluent preserves and prepares the WBC cell membrane for the differential reaction. The lysing
reagent has a differential mode of action on the WBC cytoplasmic membranes.
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When the ABX Lyse reagent reacts with the lymphocytes, the cytoplasm and the membrane are
destroyed. At the end of the lysing action, it only remains the nucleous, who has a small volume.
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When the ABX Lyse reagent reacts with the monocyte cytoplasmic membrane, it has an
intermediate reaction who empties cytoplasm from the cell. At the end of the lysing action, the
monocyte cells obtained have an intermediate size between the lymphocytes and the
granulocytes.
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When the ABX Lyse reagent reacts with the granulocytes, it has a limited reaction due to a
molecule in their cytoplasmic structure which protects them from the shrinking action of the lyse.
This in turn makes the granulocytes the larger of the WBC sub-populations in the cell
differentiation.
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After the differential lysing action, the ABX Micros ES60 OT/CT analyses the height of each
electronic pulse as the WBCs pass through the micro-aperture. The pulses are then channeled,
thresholded, grouped according to their size from 30fl to 450fl and calculated mathematically to
create the WBC distribution curve which inturn is known as the WBC histogram.
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The 3 sub-populations of WBCs are placed accordingly as to the number of cells and size of the
cells in each group.
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The distribution of the WBC sub-populations are as followed:
The lymphocytes are between 30 - 100fl.
The monocytes are between 100 - 150fl.
The granulocytes are between 150 - 450fl.
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This in turn creates the term (LMGs) for a 3 part WBC differential on the ABX Micros ES60 OT/CT.
Diag.3-14 Platelet distribution curve
PDW and PCT have not been established as indications for this product, in the
United States. The use of PDW and PCT should be restricted to research and
Investigational measurements only.
S1 S2