Given an abstract, generate a keyword (a noun phrase) that best describes the focus or contribution of the paper. Such keywords can be directly from the given abstract or outside it.

Q: Abstract: An orientated substratum has been implicated in the development and regeneration of axons and synapses. We prepared a basement membrane matrix from autogenous striated muscle, used it to repair the sciatic nerve in rats, then investigated the results by histology and electrophysiology. When treated grafts were coaxially aligned with the nerve fascicles functional recovery appeared within 30 days, with good growth of axons into the distal nerve. Grafts with myotubes at right angles to the nerve fascicles supported nerve regeneration but at a slower rate. Grafts of coaxially aligned but untreated muscle allowed axon penetration only through naturally degenerated muscle fibres, with minimal axon penetration of the distal nerve. It is concluded that in the rat a treated graft with correctly orientated empty myotubes can facilitate and guide the regeneration of peripheral nerve after injury and so lead to recolonisation of the distal stump with functional recovery.

A: Animal
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Q: Abstract: For the treatment of familial hypercholesterolemia, Liposorber LA-40 was clinically applied. The Liposorber is a commercially developed affinity adsorbent for plasma perfusion which selectivity adsorbs low density lipoproteins and very low density lipoproteins and is specially designed for plasmapheretic treatment of hypercholesterolemia. The Liposorber column, containing activated cellulose beads having an affinity for lipoprotein containing apolipoprotein-B, has an excellent adsorption capacity, excellent selectivity, minimum albumin loss. This new apheresis system was applied to 2 clinical cases. After seven months of trial perfusion every 2 weeks, patient condition was good, with a level of total cholesterol under 300 mg/dl. No replacement fluids were given during or after treatment. In this paper, clinical results of these patients were shown and the mechanism of adsorption of this specific adsorbent was discussed.

A: Adsorption
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Q: Abstract: Thirty-five patients with complete myelopathies secondary to cervical spine fractures from C-4 to C-7 underwent spinal decompressions and fusions between 1975 and 1981. Twenty-five of these patients underwent simultaneous nerve root decompressions, 23 with an accompanying anterior decompression and fusion and 2 with an accompanying posterior fusion. Substantial recovery of nerve root function occurred in 15 of these patients. A posterior reduction and fusion without nerve root decompression was performed in each of the remaining 10 patients. None of these patients demonstrated a significant improvement neurologically. Operation for nerve root decompression is indicated in selected victims of spinal cord injury.

A:
Cervical Vertebrae
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