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排序方式: 共有401条查询结果,搜索用时 15 毫秒
31.
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The incidence of adenocarcinoma and dysplasia in Barrett''s esophagus 总被引:17,自引:0,他引:17
J. Barry O''Connor M.D. Gary W. Falk M.D. Joel E. Richter M.D. 《The American journal of gastroenterology》1999,94(8):2037-2042
OBJECTIVE: The reported incidence of adenocarcinoma in Barrett's esophagus is variable. The aim of this study was to determine the incidence of dysplasia and adenocarcinoma in a population of patients with Barrett's esophagus followed prospectively and to compare these findings with other series. METHODS: All patients enrolled in the Cleveland Clinic Foundation's Barrett's esophagus registry from 1979 to 1995 were followed. Barrett's esophagus was defined as intestinal metaplasia anywhere in the tubular esophagus. The incidence of dysplasia and adenocarcinoma in these patients was recorded systematically. RESULTS: A total of 136 patients (91 male, 45 female) were followed in an endoscopic surveillance program for a mean of 4.2 yr and a total of 570 patient-years of follow-up. Thirty patients (22%) had short segment Barrett's esophagus. Two adenocarcinomas developed during follow-up, yielding an incidence of one per 285 patient-years of follow-up. Low grade dysplasia developed in 24 patients, whereas high grade dysplasia developed in four patients. CONCLUSIONS: Our study suggests that the incidence of adenocarcinoma in Barrett's esophagus is lower than initially thought. However, large multicenter studies are required to clarify the epidemiological and clinical factors related to the development of dysplasia and adenocarcinoma in Barrett's esophagus. 相似文献
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L S Teh G M O''Connor M M O''Sullivan J C Pandit L Beck B D Williams 《Annals of the rheumatic diseases》1990,49(6):410-411
Two patients with Behçet''s syndrome and intracranial hypertension are reported. One developed a recurrence of papilloedema while receiving treatment but eventually made a full recovery, whereas the other developed optic atrophy within three months of onset despite treatment. 相似文献
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J Yasky MD M Verho MD TP Erasmus MMedSc HG Luus PhD M Angela MD L Grandin MD MA Akbary MD B Rangoonwala PhD 《International journal of clinical practice》1996,50(6):302-310
SUMMARY This double-blind, randomised, cross-over study investigated the antihypertensive efficacy of ramipril and enalapril was completed by 30 patients with mild-to-moderate essential hypertension. After a four-week placebo run-in phase, the patients received either 2.5mg ramipril or 10mg enalapril once daily for four weeks. The dosages were increased to 5mg ramipril and 20mg enalapril for a further four weeks. After a placebo washout phase of four weeks, the patients were crossed over to the alternative treatment. The decrease in average 24-hour ambulatory diastolic blood pressure from week 0 to week 8 was 1.6mmHg greater with ramipril than enalapril (90% confidence interval 0.6-2.7mmHg). The corresponding reduction in for systolic blood pressure was also greater with ramipril than enalapril by 2.4mmHg (90% confidence interval: 0.5-4.2mmHg). For the difference in the drop of 24-hour ambulatory diastolic blood pressure between ramipril and enalapril the lower level of the 90% confidence interval (CI) is above the clinically relevant difference of -3mmHg. This is an indication that ramipril (2.5 and 5mg dose) is at least as effective as enalapril (10 and 20mg dose) in decreasing blood pressure in patients with mild-to-moderate essential hypertension. The duration of adequate antihypertensive effect was relatively long for both ramipril and enalapril; however, ramipril tended to have a more prolonged antihypertensive effect. Ramipril had a higher diastolic and systolic trough/peak ratio than enalapril, resulting in a more uniform antihypertensive effect over the 24-hour treatment period. Both ramipril and enalapril were well tolerated and the two treatment groups had similar safety profiles. 相似文献
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The Viral Activation Transfusion Study (VATS): rationale, objectives, and design overview 总被引:1,自引:0,他引:1
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Although reactions to granulocyte transfusions in neonates are rarely reported, we observed a near-fatal pulmonary reaction, presumably due to white cell antibodies, in a neonate with Rh hemolytic disease. The hemolytic disease was being treated with exchange transfusions, and at 2 days after the infant's birth, bacterial sepsis was suspected and granulocyte transfusions were begun. The first granulocyte transfusion (Day 3) was uneventful. Five minutes after the beginning of the second granulocyte transfusion (Day 4), severe respiratory distress, hypotension, bradycardia, cyanosis, and acidosis suddenly occurred. The infant's serum obtained after the reaction contained granulocytotoxic and B-lymphocytotoxic antibodies that reacted with leukocytes from the second granulocyte donor. Antibodies could not be detected either in the initial infant serum or in maternal serum. However, an antileukocyte antibody was present in the serum of a parous woman donor. We used plasma from this woman to prepare reconstituted whole blood for the exchange transfusion that we performed immediately preceding the second granulocyte transfusion. Despite the sequence of events, an irrefutable cause-and-effect mechanism could not be established because the properties of the donor and neonatal antibodies were similar, but not identical. However, this catastrophic event emphasizes both the potential for adverse effects of granulocyte transfusions in neonates and the need for caution when transfusing blood from parous women. 相似文献
39.
随着检测技术进步,含7个跨膜α螺旋结构的受体性质已渐为人们所了解。7次跨膜(7TM)受体不仅具有开关功能,更类似于信息微处理器;特定配体只能参与特定受体介导的部分信号机制,这就为药物发现开拓了一个新领域。为进一步发现7TM受体与配体间的新行为并量化评价药物对这一复杂系统的作用效能,进而指导药物化学研究,药理学检测已成为关注焦点。本文阐述从还原重组体到整体系统测定方法的回归,讨论药物效价与评价其效应的特定检测方法间的联系,强调新的检测方法在药物发现过程中的价值。 相似文献
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