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Digestive Diseases and Sciences - Acute kidney injury is seen in approximately 30% of patients with severe alcohol-associated hepatitis (AH) and is associated with increased mortality. Controversy...  相似文献   
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Diurnal variations of neurocardiac rhythms in acute myocardial infarction.   总被引:2,自引:0,他引:2  
To determine the diurnal pattern of cardiac autonomic tone in acute myocardial infarction (AMI), this study examined the power spectrum of heart rate (HR) variability in 24 patients during a single 24-hour segment within 4 days of AMI. Patients were nonrandomly allocated to a group (n = 14) without autonomic drugs and to a group (n = 10) already receiving beta blockers at the time of AMI. With use of autoregressive modeling, the power spectrum of HR variability was computed from continuous 1-hour electrocardiographic segments recorded at equally spaced intervals; 7 to 8 A.M., 3 to 4 P.M., and 11 to 12 P.M. All patients were supine, awake and pain free during recordings. There were no differences in HR, HR variance or the low-frequency peak power (0.06 to 0.1 Hz) from one temporal sequence to another. For the patients not taking beta blockers, the high-frequency peak power (0.2 to 0.36 Hz) or vagal component increased significantly from 3 P.M. to 11 P.M. (28 +/- 11 to 45 +/- 20 beats/min2.Hz-1, p less than 0.01). There was a significant decrease in the low- to high-frequency peak power and area ratios from 3 P.M. to 11 P.M. All power spectral parameters in the patients taking beta blockers remained unchanged over 24 hours. There was significantly heightened vagal modulation of sinus node activity in those receiving beta blockers, especially at 7 A.M. and 3 P.M. The data suggest that under steady-state wakeful conditions in the early recovery phase after an AMI, vagal tone is more pronounced during the late evening hours with a possible shift to relative sympathetic dominance during early morning and midafternoon hours.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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The role of endoscopic ultrasound (EUS) in the diagnosis of biliary strictures is well established, and emerging evidence suggests it may also play a therapeutic role. Differentiating between benign and malignant causes of biliary strictures can be challenging, but EUS can aid in their diagnosis and may predict resectability. The diagnostic yield of EUS combined with fine-needle aspiration (FNA) is excellent, especially in distal bile duct strictures, and far surpasses endoscopic retrograde cholangiopancreatography (ERCP) with brushings. Intraductal ultrasound may add to the diagnostic sensitivity of ERCP with brushings when no mass is seen on cross-sectional imaging or EUS, or when EUS with FNA is negative and suspicion of cancer persists. EUS-guided cholangiography is an emerging technique that may aid biliary decompression when ERCP has failed or is not possible; however, new therapeutic echoendoscopes or accessories are needed before the use of this technique can become more widespread.  相似文献   
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With increasing life expectancy and the older mean age of the general population, the prevalence of atrial fibrillation is likely to increase, making this arrhythmia an even more important public health problem, especially in the elderly. While atrial fibrillation is increasingly common in the elderly, paradoxically, the data on intervention trials in atrial fibrillation among the elderly are limited. When considering anticoagulation in the elderly patient with atrial fibrillation, the following five questions should be addressed. 1) Is there a definite indication (for example, atrial fibrillation plus risk factor[s])? 2) Is there a high risk of bleeding or strong contraindication against anticoagulation? 3) Will concurrent medication or disease states significantly increase bleeding risk or interfere with anticoagulation control? 4) Is drug compliance and attendance at anticoagulant clinic for monitoring likely to be a problem? 5) Will there be regular review of the patient, especially with regard to risks and benefits of anticoagulation? Careful and continuing evaluation of the elderly patient with atrial fibrillation is necessary to ensure that the risks of bleeding do not outweigh the benefits from anticoagulation.  相似文献   
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