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报道新化合物A-失碳-17β-羟基-17α-乙炔基-Δ3(5),9(10)-雌甾二烯-2-酮2的合成。文中探讨了用炔钾粗品对A-失碳-Δ3(5),9(10)-雌甾二烯-2,17-二酮1和A-失碳-6β,19-环氧-Δ3-雄甾-2,17-二酮3的选择性炔化,分别得标题化合物2(44%)及A-失碳-17β-羟基-17α-乙炔基-6β,19-环氧-Δ3雄甾-2-酮4(65%),4经还原性破开环氧、去羟甲基和去醋酰氧基合成了标题化合物2。四步总收率为34%。 相似文献
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Two modified helical basket extractors are described that have increased the success rate of removing ureteral calculi using fluoroscopy from 63% to 92%. Initially a rather stiff and expandable basket with a 20-cm filiform tip is used with coaxial catheters and sheath (stage 1). If this procedure is unsuccessful, a basket with two long cable ends is passed from the nephrostomy out through the urethra (stage 2). When used with coaxial bladder catheters, this technique allows dilatation of the vesicoureteric junction and retrograde catheterization and injection of fluids or gas to dislodge the stone prior to extraction. In a series of 38 patients, stones were removed in all but three (a success rate of 92%). In five cases small stones (less than 5 mm) were not retrieved but subsequent studies were normal. Ureteral stones were found in the abdominal ureter in 28 cases, in the pelvic ureter in seven cases, and in multiple sites in three cases. Stones were larger than 1 cm in 27.7% of cases. Postextraction mucosal edema with reduced ureteral patency was common but usually cleared in 2-3 days. Occasional complications were related to the nephrostomy. 相似文献
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E W Richards M Abu Khaled C L Watkins C L Long 《Nutrition (Burbank, Los Angeles County, Calif.)》1991,7(5):344-346
Nuclear magnetic resonance (NMR) spectroscopy has been reported as an alternative method for quantitating deuterium oxide concentrations in the evaluation of total-body-water in humans. However, the presence of dissolved plasma proteins results in an underestimation of deuterium NMR (2H-NMR) intensity ratios, thereby causing an overestimation (5-6%) of total-body-water (TBW) values determined from nonsublimed patient plasma samples. We demonstrate that plasma samples must be corrected for the volume percentage of water in plasma. Correction of initial 2H-NMR intensity ratios with a factor of 0.93 results in intensity ratios comparable to those determined from plasma samples subjected to vacuum sublimation to remove all plasma solutes. 相似文献
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Spatial summation of thermal pain has recently been reported when stimulus presentations were restricted within a single dermatome. The present study examined whether the magnitude of spatial summation of human thermal pain perception would vary when stimuli were presented within vs. between adjacent dermatomes. Noxious contact heat stimuli from 43 degrees C to 51 degrees C (5 sec duration) were applied to the forearm using areas of 0.21-2.10 cm2. Subjects rated the intensity and unpleasantness of pain using visual analog scales. For stimuli from 45 degrees C to 51 degrees C, there was a significant increase in ratings with increasing stimulus area for both intensity and unpleasantness. When two thermodes were used simultaneously in adjacent dermatomes, the ratings did not differ significantly from those for the same stimulus area in a single dermatome. We conclude that spatial summation both within and between dermatomes plays a significant role in thermal pain perception across the range from threshold to tolerance. 相似文献
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Improved survival rates for patients with major burn injuries and the consistent finding of significant long-term psychologic disability among survivors of burn trauma call for a redefinition of the role of the psychiatric consultant in the care of patients with burns. In addition to the traditional functions of diagnosis and treatment of discrete psychiatric disorders in patients with burns, this expanded role includes assisting the patient's normal process of psychologic adaptation after injury, assessing and managing burn pain, and facilitating communication among all members of the burn team. The functions of the psychiatrist are most effectively carried out when the psychiatrist is able to participate on a regular basis in the care of every patient as a member of the burn team. 相似文献
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Summary A retrospective study of 61 patients with glomus jugulare tumours treated at the National Hospital for Neurology and Neurosurgery, and at the Royal National Throat, Nose and Ear Hospital, London. The average age at presentation was 41.7 years. The patients were mainly treated by a posterolateral combined otoneurosurgical approach. 42/61 of the patients had total or subtotal excision of their tumours, 7/61 had partial removal and the remaining 11/61 had no operation. Only one case required a 2-staged procedure. There were two deaths in the postoperative period, one from intracerebral haemorrhage and the other from the left hemisphere infarction.Postoperative radiotherapy was given to 5/7 of the patients who had partial removal. 3/40 of the patients with total removal had postoperative radiotherapy, and a further 3/40 had received radiotherapy pre-operatively.Of the 11 patients who did not undergo surgery, 7/11 were treated with radiotherapy and 4/11 had embolisation only. 相似文献