BRIGHT OTF 5000, Инструкция по эксплуатации

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OTF 5000/HS/LS-001/2/3/4 Iss 4 June 2012
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3.3 TRIMMING THE SPECIMEN
1. Fit a sharp knife in position. Allow the knife to equilibrate to chamber temperature.
2. Lock the handwheel with the specimen holder in the top position.
FIG 24
3. Fit the specimen into the microtome.
4. Release the knife block clamp locking lever and turn the coarse
advance control to bring the knife towards the specimen.
5. Either rotate or rock the handwheel while using the knife carriage
feed control or use the section thickness mechanism (at 10-20µm)
and rotate the handwheel to trim the tissue.
NB: If rocking the handwheel, ensure trimming is done on the downstroke (handwheel knob in 1
o’clock round to 5 o’clock position). Trimming on the upward (retraction) stroke will result in a
subsequent very thick section and may damage the specimen.
3.4 SECTION CUTTING AND COLLECTION
1 After trimming, lock the knife block clamp locking lever FIG 16(3) firmly downwards. Set
the section thickness control to the desired position.
2
It may be necessary to cut a few sections off first to clear trimming marks.
3
Once sections are seen to be cut, place the anti-roll FIG 16(15) plate against the knife
and proceed to cut sections. if adjustments to the anti-roll plate are required, see
section 2.2.8.
4
To collect sections, have a clean microscope slide ready at ambient temperature. Bring
the slide towards the knife, swing the anti-roll plate out of the way, and move the slide
very close to the section(s). The section(s) should jump across the gap and stick to the
slide.
NB: Keep the knife clear of debris and frost by brushing upwards with the knife cleaning
brush. Never brush along or down the knife, always brush upwards.
•
Beware of debris build-up on the back of the knife.
•
Cut with a slow, steady movement.
•
Sometimes, especially with soft tissue such as brain, the best results can be obtained
with a very slow approach to the knife and then accelerating through the cut.
3.5 HINTS ON SECTIONING
1 Always start by turning the hand wheel slowly to cut the first sections. Later it may be
found that the best sections are obtained by varying the speed of cut.
2
Don’t trim too thickly - you might damage the tissue internally.
3 If the anti-roll plate seems to be giving problems, first make sure that you can cut good
sections of embedding compound without the anti-roll plate by teasing off sections using
a fine brush.
4 Make sure that the knife and the anti-roll plate are suitably cold. It can often help to use a
short blast of Cryospray 134 if this is in doubt. If Cryospray 134 is used, make sure that