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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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The role of growth factors and cytokines in the impaired healing of chronic leg ulcers remains uncertain. The aim of this study was to determine whether changes in the amount and location of cytokines and growth factors may be associated with impaired healing in chronic leg ulcers. Biopsies from leg ulcers of 21 patients and from normal skin of nine healthy volunteers were examined immunohistochemically for selected growth factors and cytokines. Greater staining intensity was found in keratinocytes at the edges of ulcers compared to normal skin, or skin adjacent to the ulcers. Staining at the ulcer edge was more intense in nonhealing ulcers for only vascular endothelial growth factor and platelet-derived growth factor, whereas staining in the adjacent skin was more intense for all factors in the nonhealing phase. For all factors staining was cytoplasmic, suggesting production in these areas. This study shows up-regulation of the production of cytokines and growth factors in keratinocytes of chronic leg ulcers that is greater when the ulcers are nonhealing. 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
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Lawrence Watkins Richard Hayward Unday Andar William Harkness 《Child's nervous system》1994,10(2):87-90
A prospective study was undertaken of all children referred to the Hospital for Sick Children with a provisional diagnosis of shunt blockage over a 5-month period. Fifty-two admissions were recorded, relating to 45 children, 5 of whom had multiple admissions. Only 19 of the 52 admissions led to a final diagnosis of shunt malfunction. No source of referral, whether by the child's general practitioner or from another hospital, was found to be more accurate than direct referral by the parents to the neurosurgical ward. Headache, vomiting and irritability were not significant indicators as to whether the child's shunt was actually blocked, and nor was the duration of the symptoms. Drowsiness was a significant, but not definite, indicator of shunt blockage, while pyrexia made it more likely that the patient had an alternative diagnosis. In 35 of the admissions a computed tomographic scan was performed: a normal scan, unchanged from previous scans, did not reliably exclude the diagnosis of shunt blockage. Percutaneous manometry via the reservoir of the shunt system was performed during 26 admissions: this investigation produced no false positives nor false negatives, but was equivocal in 5 cases, all of which were found at surgery to have a definite shunt blockage. The accuracy of the diagnosis of shunt blockage made prior to referral to a neurosurgical unit is discussed, together with the implications for resource use. 相似文献