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The mortality of acute superior mesenteric artery occlusion and mesenteric infarction remains high, in part because of the failure to identify the patients with the disorder. A reliable noninvasive diagnostic study may facilitate earlier definitive diagnosis and therapy. Proton magnetic resonance imaging may offer a noninvasive diagnostic alternative. We examined this possibility by using an experimental rabbit model of acute superior mesenteric artery occlusion in this study. Animals were scanned 1 hour after the ischemic insult. Relative intestinal wall signal intensity was increased in experimental (ischemic) animals when compared to sham operated controls on T2-weighted (4.35 +/- 0.5 vs 2.57 +/- 0.31, p less than 0.02) and proton spin density-weighted images (2.1 +/- 0.2 vs 1.4 +/- 0.21, p less than 0.05). Significant increases in image intensity were found on T2-weighted and proton spin density images when compared to control animals. Differences between groups could be further highlighted after the administration of a paramagnetic contrast agent gadolinium diethyltriamine pentacetic acid on T1-weighted images. The data from this preliminary study demonstrate that proton magnetic resonance imaging may be used to discriminate between ischemic and nonischemic small intestine. This noninvasive tool may someday become clinically useful to enhance our diagnostic capabilities when a diagnosis of acute superior mesenteric artery occlusion is being entertained. 相似文献
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A case of hepatic myelolipoma is described, including the angiographic and computed tomographic appearance. Only three such cases have been reported previously. 相似文献
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Michael B. Maron Steven M. Horvath Dr. James E. Wilkerson 《European journal of applied physiology》1977,36(4):231-238
Summary The occurrence of possible prolonged alterations in plasma levels of cortisol, epinephrine, norepinephrine, selected energy metabolites, and water and electrolyte balance was assessed in six highly trained male marathon runners by measuring blood biochemical constituents on the 10th day before and for the three days following the running of a marathon. Post-race changes in hemoglobin, hematocrit, and protein levels indicated that a hemodilution had occurred, possibly as a result of elevated sodium levels. Epinephrine remained elevated until the second day. Cortisol was depressed on the first and third post-race days while variable levels were observed on the second day. No prolonged alterations were noted in norepinephrine, FFA, glycerol, triglycerides, glucose, lactate, and pyruvate.This work was supported in part by the Air Force Office of Scientific Research, Air Force Systems Command, Grant AFOSR 73-2455 相似文献
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This investigation compared the safety and efficacy of 3- and 5-mg doses of prostaglandin E2 topical gel used for cervical ripening in 60 high-risk obstetric patients before oxytocin induction of labor. Both dosages significantly increased the Bishop score, unrelated to parity or gestational age. Induction time was significantly shortened, and the average maximum amount of oxytocin required was significantly less with the 5-mg dose, but not with the 3-mg dose, when compared with a placebo. Prostaglandin E2 did not influence the cesarean section rate. Uterine contractions were stimulated in 87.5% of the patients who received the drug, and 37.5% went into active labor, suggesting that prostaglandin E2 in these dosages is not an appropriate agent for local cervical ripening. 相似文献