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121.
Carotid and vertebral artery dissections typically occur in young adults after major trauma, although they can arise spontaneously or after trivial injury. Many patients with carotid dissections have minor symptoms such as a subject bruit or Horner's syndrome. Cephalic pain is also frequent and often inaugural in carotid dissection. However, extracranial dissection is a well recognised cause of ischaemic stroke. The diagnosis of dissection was based on angiographic findings. Noninvasive imaging also allows prompt and reliable diagnosis. Our goal was to demonstrate the spectrum of neuroradiologic (CT, MR and angiographic) findings in craniocervical arterial dissection and compare the diagnostic utility of CT, MR, MR angiography. Clinical data imaging studies, and outcome were reviewed and compared with the results in four patients with carotid artery dissection. 相似文献
122.
123.
Klaus Fröhlich Öve Gerfried Zeichen 《e & i Elektrotechnik und Informationstechnik》1998,115(4):226-226
Ohne Zusammenfassung 相似文献
124.
P. Bruelemans P. Janssen K. D. Möller 《Journal of Infrared, Millimeter and Terahertz Waves》1996,17(1):51-59
The construction of a Fourier transform spectrometer to study magnetic resonances in solids is described. The spectrometer operates in the Far Infrared (maximum frequency of 500 cm?1) and is based on a wavefront dividing interferometer with circular geometry. To illustrate the performance, a water vapour spectrum is given. 相似文献
125.
Ricardo Garcia-Padron Dan Loyd Stefan Sjökvist 《Subsurface Sensing Technologies and Applications》2002,3(2):125-150
One promising method of locating buried objects, such as land mines, is to use optical systems for detecting contrasts in surface temperature. With enhanced knowledge about the interacting physical processes behind these temperature contrasts, it is possible to improve detection precision. In such a context, moisture movement in the soil and moisture evaporation from the surface have been found to be of particular interest. This study was based on indoor experiments on wet and dry sand exposed to radiation from a solar panel. Simulations of heat and moisture transfer conducted with a one-dimensional model are also presented for the experiments. The calculations were successful in accurately predicting surface temperatures for both wet and dry sand, making it possible to predict surface temperatures under different conditions. These findings will contribute to increasing the probability of successful detection of buried objects under real conditions using optical methods. 相似文献
126.
127.
128.
S. Brabetz R. Weidl F. Klemm L. Dörrer F. Schmidl P. Seidel 《Journal of Low Temperature Physics》1997,106(3-4):527-532
We investigated different types of high-Tc DC-SQUID gradiometers with the aim to develop an one-channel heart monitoring system for non-invasive measurements in unshielded
environment. This system could be used to obtain information about the patients condition in serial examinations and in emergency
cases fast and stable. Step-edge and bicrystal Josephson junctions were used to prepare planar galvanically coupled thin film
gradiometers and magnetometers. These sensors were used to carry out measurements in well-shielded and non-shielded environment
and we compared the different noise properties and field gradient resolutions. With different types and sizes of high-Tc DC-SQUID sensors magnetocardiograms were measured in a magnetically shielded room. The influence of antenna configurations,
SQUID parameters, and cooling conditions on the measurement of magnetocardiograms will be discussed. We investigated possibilities
to suppress the earth magnetic field (with pairs of Helmholtz coils) and for noise field compensation in unshielded environment. 相似文献
129.
Analysis of lipid classes by solid-phase extraction and high-performance size-exclusion chromatography 总被引:1,自引:0,他引:1
Anu I. Hopia Vieno I. Piironen Pekka E. Koivistoinen Lea E. T. Hyvönen 《Journal of the American Oil Chemists' Society》1992,69(8):772-776
An improved method to analyze lipid classes of edible oils and fats by solid-phase extraction (SPE) and high-performance size-exclusion chromatography (HPSEC) is presented. A mixture of lipid standards was fractionated by the solid-phase extraction procedure (NH2 phase) into polar and nonpolar fractions; these were then submitted to analysis by HPSEC. The size-exclusion chromatographic columns were three styrene/divinylbenzene columns with pore sizes of 100 Å and 50 Å. Light-scattering was used for the detection system, and the parameters of the detector were optimized to minimize the difference between the responses of the compounds studied. With this procedure it was possible to separate the following lipid classes: triacylglycerols, diacylglycerols, monoacylglycerols and free fatty acids, sterols, sterol esters, tocopherols and carotenoids. Quantitative analysis was studied for a light-scattering detector with several lipid standards of different molecular weights and unsaturation levels. 相似文献
130.