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Sonographic breast imaging has been useful in the differentiation of cystic from solid masses. It has also been helpful in the characterization of palpable breast masses in the absence of corresponding abnormalities. The authors undertook a prospective study that incorporated pulsed Doppler analysis into sonographic real-time imaging of solid breast masses. Thirty-eight patients were examined. In 12 of the patients there were positive Doppler signals, while in 26 patients there were no Doppler signals. The 12 patients showing positive Doppler signals proved to have infiltrating ductal carcinoma, while the 26 patients with negative Doppler signals proved to have benign breast disorders. Pulsed Doppler analysis as a supplement to sonographic real-time imaging shows promise for the identification of breast carcinoma. 相似文献
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J T Baker A E Nicogossian G W Hoffler R L Johnson 《Aviation, space, and environmental medicine》1976,47(4):400-402
A generalized hyperreflexia was observed in Skylab 2 crewmembers during the immediate postflight clinical evaluations. Unfortunately, no provisions had been made to quantitate the observed phenomenon. The cause of the hyperreflexia was not readily apparent at the time of the observation. Reflex changes have been noted in several of the Russian cosmonauts after extended spaceflight. Prior to the launch of Skylab 3, it was decided to measure and record a single tendon reflex and, if possible, the associated muscle potential. Duration of the Achilles reflex immediately postflight showed a significant (p greater than 0.01) shortening for all three crewmen. The reflex duration exhibited further significant shortening from preflight values on the fourth day after recovery. At the 16th day measurement, there was a signficant lengthening of the reflex for crewmenber 2 and 3 while crewmember 1 showed some lengthening which was not significant. By 29 d postrecovery, the reflex time of crewmember 1 had returned to his preflight value while the other two crewmen continued to show a significant lengthening of the reflex, although both were showing trends toward their preflight values. The muscle potential intervals were shortened immediately postflight and remained shortened during the 29 d of postflight evaluation. Currently, work is in progress to correlate these findings with other observed anatomical, physical, and biochemical changes. Final conclusions and an in-depth statistical analysis will be presented at a later date. 相似文献
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Preliminary experimental results in humans and animals with a superconducting, whole-body, nuclear magnetic resonance scanner 总被引:3,自引:0,他引:3
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