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Nocturnal urinary melatonin excretion was significantly decreased throughout an ovarian cycle in 12 migraine without aura patients compared to 8 healthy controls. Normal increases in urinary melatonin excretion during the luteal phase was less pronounced in the migraine patients. Melatonin excretion was further decreased during headache. The data indicate impaired pineal function in migraine.  相似文献   
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Fifty-one patients (42 men; 60 +/- 12 years of age) who had previous stent implantation underwent multislice computed tomographic coronary angiography. All coronary branches > or = 2.0 mm were independently evaluated by 2 observers and screened for in-stent restenosis (> or = 50%) and occlusion. The consensus reading was compared with the quantitative coronary angiogram. Six of the 74 (8.1%) evaluated stents (3 restenoses and 3 occlusions) were significantly diseased. The sensitivity, specificity, and positive and negative predictive values to identify restenosis were 83.3% (95% confidence interval [CI] 35.9 to 99.6), 98.5% (95% CI 92.1 to 100), 83.3% (95% CI 35.9 to 99.6), and 97.3% (95% CI 92.1 to 100), respectively. One in-stent restenosis remained undetected.  相似文献   
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Background Colorectal cancer (CRC) is one of the most common types of cancer in European countries and associated with a high mortality rate. A 16% relative risk reduction (RRR) of mortality was found in a meta‐analysis based on four randomized controlled trials (RCT) on CRC screening. The aim of this paper was to scrutinize these trials for potential biases and assess their influence on the screening trials. Methods The four RCTs were reviewed based on the principles of ‘Critical Appraisal of the Medical Literature’. Principal investigators of the four RCTs were contacted to clarify uncertainties in their study. Data were collected from The Danish Data Archives. Authors of the Cochrane review were contacted. Results Six biases were identified, of which five favour screening. Three of the biases identified were specific to CRC screening: type of diagnostic method, place of surgery and diagnostic delay. Conclusion The 16% RRR in CRC mortality found in the updated Cochrane review's meta‐analysis is overestimated.  相似文献   
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In a population-based study of 3962 community-dwelling nondemented elderly we investigated the relation of age, sex, cardiovascular risk factors, and the presence of infarcts with cerebellar volume, and its interrelationship with cerebral volumes. Cerebellar and cerebral gray and white matter were segmented using Freesurfer version 4.5 (http://surfer.nmr.mgh.harvard.edu/). We used linear regression analyses to model the relationship between age, sex, cardiovascular risk factors, brain infarcts, white matter lesions (WMLs) and cerebellar and cerebral volume. Smaller cerebellar volumes with increasing age were mainly driven by loss of white matter. Diabetes, higher serum glucose and lower cholesterol levels were related to smaller cerebellar volume. No association was found between hypertension, smoking, apolipoprotein E (ApoE) genotype, and cerebellar volume. Supratentorial lacunar infarcts and WMLs were related to smaller cerebellar volume. Infratentorial infarcts were related to smaller cerebellar white matter volume and total cerebral volume. This study suggests that determinants of cerebellar volume do not entirely overlap with those established for cerebral volume. Furthermore, presence of infarcts or WMLs in the cerebrum can affect cerebellar volume.  相似文献   
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