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71.
BACKGROUND/AIMS: Free radical-mediated oxidative stress has been implicated in the pathogenesis of acute liver injury. The aim of our study was to investigate whether melatonin, a potent free radical scavenger could prevent fulminant hepatic failure in rats. METHODS: Liver damage was induced by two consecutive injections of thioacetamide (TAA, 300 mg/kg/i.p.) at 24 h intervals. Treatment with melatonin (3 mg/kg/daily, i.p) was initiated 24 h prior to TAA. RESULTS: Twenty-four h after the second TAA injection, serum liver enzymes and blood ammonia were lower in rats treated with TAA+melatonin compared to TAA (P<0.001). Liver histology was significantly improved and the mortality in the melatonin-treated rats was decreased (P<0.001). The increased nuclear binding of nuclear factor kappa B in the livers of the TAA-treated rats, was inhibited by melatonin. The hepatic levels of thiobarbituric acid reactive substances, protein carbonyls and inducible nitric oxide synthase were lower in the TAA+melatonin-treated group (P<0.01), indicating decreased oxidative stress and inflammation. CONCLUSIONS: In a rat model of TAA-induced fulminant hepatic failure, melatonin improves survival and reduces liver damage and oxidative stress. The results suggest a causative role of oxidative stress in TAA-induced hepatic damage and suggest that melatonin may be utilized to reduce liver injury associated with oxidative stress.  相似文献   
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This study examined associations between three parent–child engagement states and social communication, expressive language, and receptive language at 8 month follow-up, in 63 preschool-age children with autism spectrum disorder. We extend the literature on supported joint engagement by dividing this state into higher order (HSJE) and lower order types, with HSJE involving greater reciprocity in toy play. We also examined parents’ follow-in utterances that co-occurred with each state. We found that only HSJE predicts later social communication and expressive language, while object engagement predicts receptive language. HSJE combined with follow-in utterances (HSJE+FI) predicts all three outcomes when controlling for HSJE+FI in other engagement states. When controlling for total HSJE, HSJE+FI is predictive of receptive language.  相似文献   
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The aim of this study was to review the life of Mary E. O'Sullivan and to summarize her important contributions to the study of migraine. Mary E. O'Sullivan underwent extensive training to become a neurologist at a time when only 5% of women in America were physicians. She published five papers on migraine. In a 1936 Journal of the American Medical Association article, she described a patient with ergotamine overuse headache and recommended that daily doses of oral ergotamine should be avoided. Three years later she described migraine as a 'complex' syndrome with multiple causes and multiple cures. Mary E. O'Sullivan, an ambitious female headache specialist of the 1930s, was an early advocate of the use of ergotamine to treat migraine, yet she was one of the first to report ergotamine overuse headache. Although her life was short, her research, knowledge and ambition at a time when women had limited opportunities in medicine have left a mark.  相似文献   
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Indium-111 leukocyte scintigraphy in suspected bowel ischemia   总被引:1,自引:0,他引:1  
OBJECTIVE: The purpose of this study was to evaluate the utility of indium-111 leukocyte (In-111 WBC) scintigraphy in a large number of patients with suspected bowel ischemia. METHODS: All patients who underwent In-111 WBC scintigraphy for possible bowel ischemia over a 4-yr period and had subsequent endoscopic or surgical biopsy were retrospectively evaluated. Early (1-4 h postinjection) and late (18-24 h postinjection) images were obtained. Any study with tracer activity in the bowel on early or late images was considered positive for bowel ischemia. RESULTS: Fifty-nine patients were included in the analysis. In-111 WBC scintigraphy detected 23 of 24 cases of bowel ischemia (sensitivity = 96%). Of 35 cases without ischemia, 16 had a negative In-111 WBC scintiscan (specificity = 46%). Negative and positive predictive values for the diagnosis of bowel ischemia were 94% and 55%, respectively. Of the 19 cases without bowel ischemia and a positive scintiscan, 15 had another intraabdominal process responsible for the patients' symptomatology. CONCLUSIONS: In-111 WBC scintigraphy is a highly sensitive diagnostic tool for bowel ischemia. A normal In-111 WBC scintiscan strongly suggests that this disease is not present.  相似文献   
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