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R Jaeschke G H Guyatt J Singer J Keller M T Newhouse 《Canadian Medical Association journal》1991,144(1):35-39
OBJECTIVE: To examine the mechanisms through which two bronchodilators (theophylline and salbutamol) influence dyspnea during daily activities. METHODS: Twenty-four patients with chronic airflow limitation participated in a multiple crossover, randomized, placebo-controlled trial. The effect of theophylline and salbutamol, alone or combined, on pulmonary function and dyspnea during daily activities was examined. Correlations of changes in forced expiratory volume in 1 second (FEV1) and maximum expiratory pressures (MIPs) (independent variables) and changes in dyspnea score during daily activities (dependent variable) were also examined. RESULTS: The two drugs proved to be beneficial the effects in general were additive rather than synergistic. The drugs improved the FEV1; theophylline significantly improved the MIPs. The correlation between the changes in FEV1 and those in dyspnea score, after adjustment for the changes in MIPs, was 0.55 (p less than 0.001). The correlation between the changes in MIPs and those in dyspnea score, after adjustment for the changes in FEV1, was 0.39 (p less than 0.001). CONCLUSIONS: Changes in airway calibre and in respiratory muscle strength play an independent and important role in dyspnea during daily activities in patients with chronic airflow limitation. Changes in airway calibre may be of greater importance. 相似文献
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Postencephalitic acquired Tourette-like syndrome in a child. 总被引:1,自引:0,他引:1
We report a 6-year-old girl who developed a Tourette-like syndrome following presumed herpes encephalitis. This case suggests that tics can be acquired in childhood and may be associated with lesions involving basal ganglia or limbic circuitry. 相似文献
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Adam J. Singer MD Steve A. McClain MD Alexander Romanov DVM Jean Rooney BS Tom Zimmerman DVM 《Academic emergency medicine》2007,14(12):1125-1129
Objectives Cutaneous burns are dynamic injuries with a central zone of necrosis surrounded by a zone of ischemia. Conversion of this ischemic zone to full necrosis over the days following injury is due in part to highly reactive oxygen radicals. Curcumin is a component of the Oriental spice turmeric that has been shown to have antioxidant and antiapoptotic properties. The authors hypothesized that treatment of burns with curcumin would reduce the conversion of the ischemic zone to full necrosis. Methods This was a randomized controlled experiment. Twenty Sprague‐Dawley rats were used. Two burns were created on each animal's dorsum using a brass comb with four rectangular prongs preheated in boiling water and applied for 30 seconds, resulting in four rectangular 10 × 20–mm full‐thickness burns separated by three 5 × 20–mm unburned interspaces (zone of ischemia). Animals were randomized to curcumin or vehicle by oral gavage 30 minutes before injury and at 24, 48, and 72 hours after injury. Wounds were observed at one, two, and three days after injury for visual evidence of necrosis in the unburned interspaces. Full‐thickness biopsy specimens from the interspaces were evaluated with hematoxylin and eosin staining seven days after injury for evidence of necrosis. The percentage of interspaces that progressed to necrosis was compared with chi‐square tests. Results Forty comb burns with 120 unburned interspaces were created, evenly distributed between curcumin and vehicle alone. The percentage of interspaces that progressed to full‐thickness necrosis at one, two, three, and seven days after injury in the curcumin and vehicle groups were 30% versus 63% (p = 0.003), 30% versus 70% (p < 0.001), 63% versus 95% (p = 0.02), and 63% versus 95% (p = 0.02), respectively. Conclusions Pretreatment of rats with oral curcumin followed by once‐daily oral treatment for three days reduced the percentage of unburned skin interspaces that progressed to full necrosis. 相似文献
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Jonathan Singer MD 《Academic emergency medicine》2004,11(12):1327-1327
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Jean-Marie Danion Marie-Agathe Zimmermann Dominique Willard-Schroeder Danielle Grangé Marie Welsch Jean-Louis Imbs Léonard Singer 《Psychopharmacology》1990,102(3):422-424
The effects of scopolamine, an anticholinergic drug, of trimipramine, a tricyclic antidepressant with both anticholinergic and sedative properties, of diazepam and a placebo, on explicit memory and repetition priming were assessed using a free-recall task and a word-stem completion task. Forty-eight healthy volunteers took part in this double-blind study. Diazepam provoked a dissociation between free recall, which was profoundly impaired, and word completion, which was spared. No significant changes in memory performances were observed in the scopolamine group; however, a significant correlation between explicit and implicit memory performances was observed in this group. At the low dose used, the effects of trimipramine on memory were mild. The results suggest that the cholinergic system is involved in the priming effect. 相似文献
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