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In an open, randomized cross-over study in 124 patients, we compared the efficacy, safety and patient preference of oral and subcutaneous sum triptan in the acute treatment of migraine. Patients were treated for 3 attacks or 3 months and then crossed over. Primary clinical efficacy was defined as a reduction in headache severity on a four-point self-rating scale from severe (3) or moderate (2) to mild (1) or none (0), or mild (1) to none (0). Efficacy was evaluated 2 h after the administration of subcutaneous and 4h after the administration of oral sumatriptan. Subcutaneous sumatriptan was significantly more effective than oral sumatriptan in relieving headache (over all three attacks 78% vs 61% improvement), improving clinical disability (55% vs 41 % improvement) and relieving nausea (69% vs 53%), vomiting (72% vs 32%) and phono- or photophobia (67% vs 49%). Median time to recurrence was shorter after subcutaneous (12.5 h) than after oral sumatriptan (18 h); the number of patients experiencing a recurrence was similar Patients reported more adverse events after subcutaneous sumatriptan (1.32 per attack) than after the oral form (0.85 per attack), but all adverse events were mild to moderate in intensity and of short duration. Patient opinion was more often positive after subcutaneous sumatriptan. These results may be useful in counselling patients to choose between the available marketed formulations of sumatriptan.  相似文献   
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Abnormal pressor responses are known to occur in the maternal circulation in pregnancy-induced hypertension (PIH), but little is know of the response of the foetal circulation. The responsiveness of umbilical arteries in PIH can be studied after delivery, and this is a useful model to explore the pathophysiological mechanisms involved. In the present experiments, the in vitro response of umbilical artery rings to bradykinin and 5-hydroxytryptamine (5-HT) was tested and ultrastructural changes investigated. Umbilical arteries from 48 cords were studied. Fifteen of the mothers had PIH, five had essential hypertension pre-dating the pregnancy and five had diabetes. Twenty-three women had pregnancies uncomplicated by hypertension or serious medical or obstetric problems and these served as controls. Umbilical arteries from the severe proteinuric PIH group were significantly more responsive to 5-HT as assessed by affinity constants (P less than 0.05). The responsiveness of arteries from all other groups did not differ from the normal cases. A probable mechanism for the findings is endothelial damage as a result of pre-eclamptic disease. This was substantiated by ultrastructural evidence.  相似文献   
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A retrospective study was performed on 160 patients admitted to the University Surgical Unit between July 1975 and November 1989 with haemorrhoidal disease. Patients' records were analysed with respect to predisposing factors, inpatient management, postoperative analgesia, hospital stay and post-management complications. One hundred and nineteen patients had haemorrhoidectomy (low ligation combined with an anal stretch). Of these, 1.6% developed urinary retention and 4.2% bled postoperatively but did not require surgical intervention. Ten patients were found to have tight anal canals post surgery and required outpatient anal dilatation. In no case was dilatation necessary for more than 3 months. Three patients required a therapeutic course of antibiotics. Of the 119 patients, 60 required narcotic analgesia for less than 24 hours. Hospital stay was 1-4 nights.  相似文献   
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The Studies of Left Ventricular Dysfunction (SOLVD) trials were designed to evaluate the effects of enalapril on long-term mortality in patients with severe left ventricular (LV) dysfunction. Patients with LV ejection fractions less than or equal to 0.35 and symptoms of congestive heart failure (CHF) were enrolled in the treatment trial, whereas those with no history of overt CHF and taking no treatment directed for LV dysfunction were enrolled in the prevention trial. The baseline clinical characteristics of SOLVD patients were compared to characterize differences between patients in these 2 separate but concurrent trials. From over 70,000 patients screened with LV dysfunction, 4,228 patients were enrolled in the prevention trial and 2,569 patients in the treatment trial. Ischemic heart disease was the primary cause of LV dysfunction in both prevention (83%) and treatment (71%) trial patients. Prior myocardial infarction was present in 80% of the prevention and 66% of the treatment trial patients (p less than 0.001). In the prevention trial, infarction was recent (less than or equal to 6 months) in 27% patients and remote (greater than 6 months) in 57% patients. Treatment trial patients had proportionately more women (20 vs 13%; p less than 0.001) and non-Caucasians (20 vs 14%; p less than 0.001), as well as the coexisting risk factors of hypertension (42 vs 37%; p less than 0.001) and diabetes (26 vs 15%; p less than 0.001) than did prevention trial patients. Clinical characteristics of patients in both trials were influenced by the gender and race of enrolled patients. Similarly, coronary artery bypass surgery was performed less often in women and non-Caucasians.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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目的:制备分散性良好的超细β-磷酸三钙(β-TCP)/聚-L-乳酸(PLLA)复合材料及新型可吸收骨折内固定器。方法:通过研磨方法制备β-TCP超细粒子,用一缩二乙二醇作分散剂研磨β-TCP后,再将β-TCP与PLLA超声混合,制得复合材料,经注塑加工制成可吸收骨钉,并采用扫描电镜等方法进行表征。结果与结论:用一缩二乙二醇作分散剂研磨β-TCP后再经超声混合,可以使β-TCP超细粒子在复合材料中分散均匀,粒子大小仅为300nm左右,β-TCP与PLlA基体之间结合良好。超细β-TCP/PLLA复合材料可加工成可吸收骨钉,弯曲强度达到100MPa左右,完全满足松质骨内固定的要求。  相似文献   
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BACKGROUND: The aim of the study was to investigate the inhibitory control of an ongoing motor response and to identify underlying neural deficiencies, manifested in event-related potentials, that cause poorer inhibitory performance in children with attention-deficit/hyperactivity disorder. METHODS: A stop-signal paradigm with a primary visual task and auditory stop signal was used to compare performance in 13 children with attention-deficit/hyperactivity disorder and 13 control children, while event-related potentials were recorded simultaneously. RESULTS: Children with attention-deficit/hyperactivity disorder showed poorer inhibitory performance through a slower inhibitory process. Inhibitory processing of auditory stop signals was marked by a frontal N2 component that was reduced in the attention-deficit/hyperactivity disorder group relative to controls. A central positive component (P3) was associated with the success of inhibiting a response, but there were no group differences in its amplitude or latency. CONCLUSIONS: Findings support the hypothesis of deficient inhibitory control in children with attention-deficit/hyperactivity disorder. Slower inhibitory processing appears to be due to a specific neural deficiency that manifests in the processing of the stop signal as attenuated negativity in the N2 latency range.  相似文献   
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