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101.
102.
J J Phillips S L Chang H I Vargas P S Dickman J A Butler J D Lipcamon 《Magnetic resonance imaging》1991,9(2):201-204
To characterize the radiographic appearance of liver lesions over time following ethanol injection, seven New Zealand white rabbits underwent surgical implantation of small fragments of VX-2 carcinoma within the liver. Upon reaching 1 cm in diameter, a tumor nodule was directly injected with absolute ethanol. Another nodule in the same animal was injected with saline as a control. Imaging was performed 6-24 days after the injections by high resolution CT and MRI, and correlation obtained with the pathologic specimens. Long TR spin-echo MR sequences were found to characterize the ethanol-treated regions of liver most accurately. Liver tissue infarcted by alcohol could be differentiated from tumor and necrosis by virtue of its short T2 relaxation value. There were no distinguishing features by other imaging techniques between the ethanol-treated and control tumor nodules. Peripheral contrast enhancement was demonstrated in both, corresponding to fibrous tissue around the ethanol-injected regions, and to viable tumor in the case of controls. 相似文献
103.
Stephen Kishner Paul J. Fitzatrick Keith R. Plowman Ian S. Butler 《Journal of Molecular Structure》1981,74(1):29-37
Laser Raman spectra of solid dodecacarbonyl-triangulo-ruthenium(0) and -osmium(0), M3(CO)12 (M = Ru, Os), have been recorded at 295, 200, 100 and 15 K using a surface scanning technique to avoid sample decomposition. The data indicate that neither compound undergoes a phase change throughout the temperature range investigated. Contrary to earlier measurements at room temperature only, site-symmetry and correlation effects are more widespread than hitherto suspected. 相似文献
104.
Kim Ki-Hang Butler 《Semigroup Forum》1971,3(1):74-79
In this paper we count the number of elements and idempotents in certainD-classes of the semigroup Bn of all binary relations on a set of n elements, namely whose those row and column rank do not exceed 3. This is an announcement
of the results; detailed proofs of all results are contained in [2].
The author presented the abstract of this paper in person at Tacoma, Washington, the 676 Meeting of the Amer. Math. Soc.,
June 20, 1970. 相似文献
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The spectral response of a copper-doped germanium photo-conductive detector has been examined. Two series of sharp photo-thermal neutral acceptor excitations are observed; one is identified with copper impurities while the other is of unknown origin. 相似文献
110.