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Ralls PW; Johnson MB; Kanel G; Dobalian DM; Colletti PM; Boswell WD Jr; Radin DR; Halls JM 《Radiology》1986,161(2):451-454
FM sonography - a signal-processing technique that uses frequency and phase information as well as amplitude data - shows promise in evaluation of patients with diffuse liver disease. In a prospective blinded review of 37 patients with biopsy-proved liver disease and 42 healthy volunteers, FM sonography was clearly superior to traditional amplitude-based (AM) sonography in distinguishing healthy from diseased subjects. Statistically significant differences were seen in accuracy (FM, 98.7%; AM, 84.8%), sensitivity (FM, 97.3%; AM, 70.3%), and negative predictive value (FM, 97.7%; AM, 78.8%). Our data also suggest that current FM sonographic techniques cannot differentiate among histologic findings associated with different hepatic parenchymal abnormalities. It is unclear, therefore, whether FM imaging can reduce the numbers of patients who require biopsy for diagnosis or the frequency of biopsy procedures in patients with known disease. 相似文献
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Causes for failure of pregnancy after tubal reconstructive surgery are incompletely understood. The impact of microsurgical resection reanastomosis on ovum recovery was studied in the rabbit oviduct. One hundred sixty rabbits were divided into three groups: one experimental group in which a resection reanastomosis was made in the ampullar or isthmic tubal segment, respectively, and two control groups. After mating, ovum recovery was evaluated. In ampullary operated oviducts the ovum recovery rate was significantly lower compared with recovery rates in isthmically operated and in control oviducts. Furthermore, in ampullary operated oviducts peritoneal transmigration of ova was frequently observed. Disturbances in ovum pickup from the ovarian surface or the peritoneal cavity seem to be responsible for the decrease in recovery rate found in the ampullary operated oviducts. 相似文献
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The effect of laser refractive surgery on the on-field performance of professional baseball players.
BACKGROUND: The aim of this study was to determine the effect of laser refractive surgery on the offensive performance of professional baseball players. METHODS: Extensive search of the public media was conducted to determine which major league baseball players had undergone laser refractive surgery and when the procedure was performed. Baseball performance data were then used to determine presurgery and postsurgery baseball performance averages. A total of 17 position players were identified; however, 5 of these players were not considered in the analysis owing to insufficient playing experience either before or after the laser procedure. RESULTS: No statistically significant or practically significant difference was found between the presurgery and postsurgery means on either on-base percentage (P = 0.31), batting average (P = 0.39), slugging percentage (P = 0.66) or on-base plus slugging (OPS; P = 0.997) of major league baseball players. CONCLUSIONS: These preliminary findings suggest that professional baseball players should not expect a laser refractive surgical procedure to significantly improve their offensive baseball performance, despite the elimination of glasses or contact lens wear. 相似文献