INVESTIGATIONS INTO HYPERLIPIDEMIA AND ITS POSSIBLE ...

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Two filters k matching the excitation (blue-violet filter centered at 407 nm) and
emission (a yellow emission long pass filter with a cut-on wavelength of 515 nm)
characteristics of NBD C 6 -cermide were used. A gain of 1.0000, a target intensity of
30%, and an exposure time of 53.3 ms were selected. In order to be analyzed, the image
of the each tube following ultracentrifugation was converted to a density profile using a
commercially available software program. l
A tube coordinate scale was established
where 0.0 mm was the top of the tube and 34.0 mm was the bottom of the tube. 281 The
average intensity was then plotted as a function of tube coordinate.
The ultracentrifugation method described above is able to identify 11 separate
density lipoprotein fractions (TRL, 5 LDL fractions, and 5 HDL fractions). This
separation is based solely on the density characteristics of the lipoprotein fractions and
not on their functional properties. Therefore, this method was used to develop
lipoprotein fingerprinting in canine serum based on lipoprotein densities alone. Density
ranges were based on those previously published by several authors. 282 Specifically, the
11 fractions and their corresponding densities (d) were as follows: chylomicrons and
VLDL (d