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1.
Initial 31P spectroscopy results from a 4-T whole-body system are reported. Localized spectra from the human head, liver, and calf were obtained using DRESS, slice-interleaved DRESS, and volume 3DFT spectroscopic imaging techniques. Substantial reductions in data acquisition times to 10 s-4 min were achieved relative to previous similar experiments at 1.5 T. Some gain in spectral resolution (as measured in ppm) was also realized in the head.  相似文献   
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BACKGROUND: We have seen several patients with itchy lichenified plaques located bilaterally on the elbows and/or knees and have named this condition 'psoriatic neurodermatitis' (PN). OBJECTIVE: The purpose of this study was to compare clinical and histopathological characteristics of these patients to those of patients with typical lichen simplex chronicus (LSC). METHODS: Nineteen patients with PN and 34 patients with typical LSC were included. Besides clinical dermatological evaluation, the prick test was carried out on 49 patients; the Phadiatop test on 40 patients; the patch test with European standard series on 47 patients; histopathological evaluation on 39 patients; and clinical psychiatric examination on 38 patients. RESULTS: Almost exclusively, PN was seen in females and was located on the extremities. It caused more plaques than typical LSC did. In PN, the plaques were smaller, sharper, more keratotic and less excoriated, and had fewer lichenoid papules around them. Itching was usually more severe in the evening, while resting and in a hot environment in typical LSC, but not in PN. In plaques of PN, microabscesses in the horny layer, hypogranulosis, regular acanthosis and thinning of the suprapapillary plates were more frequent, and hyperpigmentation in the basal layer was less. In patients with PN, depressive disorder was found more frequently; and generalized anxiety disorder or psychosomatic characteristics, less. There were no significant differences in the results of prick, Phadiatop and patch tests between patients with PN and those with typical LSC. CONCLUSION: In our opinion, it is most likely that the so-called PN is itchy psoriasis superimposed by LSC.  相似文献   
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Narrowband irradiation of water protons with a surface coil yields significant nuclear Overhauser enhancement (nOe) of phosphocreatine (PCr) and some adenosine triphosphate (ATP) moieties in localized and unlocalized phosphorus (31P) NMR spectra from chest and heart muscle. In seven normal subjects at 1.5 T the nOe values were 0.6 +/- 0.3, 0.6 +/- 0.3, 0 +/- 0.3, and 0.3 +/- 0.2 for myocardial PCr, gamma-ATP, alpha-ATP, and beta-ATP, respectively, not significantly different from those in chest muscle. Distortion of the measured PCr/ATP ratios due to differences in the nOe may require accurate correction to realize the full benefit of the effect in studies involving quantitative intergroup comparisons.  相似文献   
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Cerebrospinal fluid (CSF) was allowed to drop straight into Hanks's balanced salt solution. After centrifugation the pellet was resuspended and mixed with sheep erythrocytes. The mixture was further handled as in the E-rosette test with peripheral blood lymphocytes. CSF from 20 individuals were investigated, and rosette-forming cells (RFC) were found in all. Six patients with normal fluid had between 46% and 83% RFC. Four patients with multiple sclerosis had increased numbers of RFC (94%-96%). Low numbers of RFC were found in one patient with cerebellar ataxia and in one of two patients with acute viral meningitis. With this technique RFC can be counted even in normal CSF with a 3-ml sample.  相似文献   
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A novel and versatile instrument for producing high quality monochrome and colour hard-copy of medical images from an array of digital information is described. Images are produced on standard photographic print paper mounted on the bed of a conventional X-Y plotter by scanning a time-modulated light source over the paper using a computer driven raster. A matrix board gives control of both greyscale and colour attribution. Examples of NMR images produced by the system are presented. A refinement of the technique which allows two variables to be displayed on one image is also described.  相似文献   
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