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Daytime sleep tendency was assessed in 10 drug-free patients with narcolepsy-cataplexy and 10 normals matched for age and gender. Following nocturnal polysomnography, the alpha attenuation test (AAT) and the multiple sleep latency test (MSLT) were administered during five sessions occurring at 2-hour intervals beginning at 0900 and 1000 hours, respectively. For the AAT, participants were polysomnographically recorded for 8 minutes while seated in an illuminated room with their eyes alternately opened and closed. Power spectral analyses of electroencephalograph (EEG) activity at 02-A1 (10 second epochs) were calculated using fast Fourier transformations (FFT) within the alpha frequency range (8-12 Hz) to obtain ratios of mean eyes-closed to mean eyes-open alpha power (i.e. the alpha attenuation coefficient, AAC). The narcoleptics were sleepier than the normals as indicated by a significantly smaller mean AAC and a significantly shorter mean latency to stage 1 on the MSLT. These findings suggest that the AAT may provide a quick and practical objective assessment of the excessive daytime sleepiness (EDS) associated with narcolepsy. 相似文献
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RD Barr T Simpson CE Webber GJ Gill J Hay M Eves AC Whitton 《Canadian Metallurgical Quarterly》1998,34(6):873-877
Mature and post-translational precursor gastrin forms are growth factors for colorectal tumours. The immunogen Gastrimmune is composed of the amino terminus of gastrin-17 linked to diphtheria toxoid and raises antibodies in situ which neutralise amidated and glycine-extended gastrin-17. The aim of the study was to determine the effect of treatment with 5-fluorouracil(5-FU)/leucovorin on the antibody titres induced by Gastrimmune and the effect of combination therapy on the growth of the rat colon tumour DHDK12. Gastrimmune was administered to rats s.c. at 3 weekly intervals. The rat colon tumour line DHDK12 was injected into the abdominal wall of BDIX rats. Combinations of 5-FU/leucovorin were injected i.v. on days 1, 3 and 5, with the cycle repeated every 4 weeks. Antibody titres were measured by an ELISA technique. Antibody titres were followed for 40 weeks after Gastrimmune (500 microg.ml(-1)) immunization, with titres peaking between 10 and 20 weeks after a single immunisation and falling by week 30. At termination, no effect was observed on either the histological appearance of the gastro-intestinal tract or the proliferation of the colonic mucosa. Pre- and post-treatment with 5-FU/leucovorin (30 mg.kg(-1)) had no effect on the kinetics and level of antibody response to Gastrimmune. Gastrimmune (200 microg.ml(-1)) and 5-FU/leucovorin combinations (12.5 and 20 mg.kg(-1)) increased the therapeutic effects on the in vivo growth of DHDK12 tumors when compared to the agents given singly. Gastrimmune immunisation may be a therapeutic option for the treatment of colorectal cancer in combination with 5-FU/leucovorin. 相似文献
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OBJECTIVE: To determine if either dopamine or dobutamine would counteract the deleterious effect that positive end-expiratory pressure (PEEP) has on cardiac output and mesenteric blood flow in a rat model of acute lung injury. DESIGN: Prospective, randomized, controlled trial in a clinically relevant model of acute lung injury. SETTING: Microcirculation research laboratory. SUBJECTS: Male Sprague-Dawley rats. INTERVENTIONS: The animals were anesthetized with pentobarbital (30 mg/kg) by intraperitoneal injection. They underwent tracheostomy, jugular and femoral vein cannulation, femoral artery cannulation, carotid artery thermistor placement, and bowel preparation for in vivo video microscopy. Acute lung injury was created by administering 0.1 N hydrochloric acid (1 mL/kg) via the tracheostomy. Dopamine or dobutamine (2.5 or 12.5 microg/kg/min), followed by two intravenous fluid boluses, was administered to rats ventilated with 5, 10, 15, and 20 cm H2O of PEEP. MEASUREMENTS AND MAIN RESULTS: Mean arterial pressure, thermodilution cardiac output, mesenteric arteriolar diameter, and red blood cell velocity were measured and mesenteric blood flow was calculated. Cardiac output was depressed in rats exposed to 20 cm H2O of PEEP by 32+/-2%. The corresponding values for cardiac output depression at 20 cm H2O of PEEP in rats receiving 2.5 and 12.5 microg/kg/min of dopamine and 2.5 and 12.5 microg/kg/min of dobutamine were 31+/-1%, 21+/-1%, 29+/-0%, and 24+/-2%, respectively. Mesenteric blood flow was depressed in rats ventilated with 20 cm H2O of PEEP by 74+/-3%, while the corresponding values in rats exposed to 20 cm H2O of PEEP and receiving 2.5 or 12.5 microg/kg/min of dopamine or 2.5 or 12.5 microg/kg/min of dobutamine were 86+/-3%, 77+/-3%, 73+/-3%, and 66+/-3%, respectively. Fluid boluses did not correct the deficits in cardiac output or mesenteric blood flow caused by the combination of acute lung injury and PEEP. CONCLUSIONS: The higher doses of dopamine and dobutamine partially, but insignificantly, corrected the cardiac output depression caused by PEEP in a model of acute lung injury. Neither dose of dopamine nor dobutamine was able to improve PEEP-induced mesenteric blood flow depression. 相似文献