Carbon-13 NMR data of [iilmetacyclophane (la), its 8,ll-dihalosubstituted derivatives lb-ld and of some model compounds are reported and discussed. A remarkable downfield shift is observed for the aromatic carbon between the bridging carbons; this is tentatively ascribed to long-range effects of the
13C NMR investigation of synovial fluids
✍ Scribed by Klaus Albert; Sabine Michele; Ulrich Günther; Manfred Fial; Hugo Gall; Johannes Saal
- Publisher
- John Wiley and Sons
- Year
- 1993
- Tongue
- English
- Weight
- 356 KB
- Volume
- 30
- Category
- Article
- ISSN
- 0740-3194
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✦ Synopsis
Abstract
^13^C NMR spectra of synovial fluids from 20 patients suffering from rheumatic diseases have been recorded. Structural changes in hyaluronic acid, the main carrier of the viscoelastic properties of synovial fluid, could be observed in the NMR spectra of the native biological fluid. By comparing these spectra with those of purified hyaluronic acid, a rough estimation of the degree of depolymerization of synovial hyaluronlic acid was possible. The patients with rheumatoid arthritis appeared to have a lower degree of polymerization compared to patients with osteoarthrosis. Thus, ^13^C NMR spectroscopy prolvides useful information about biophysical properties of sartorial fluid.
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