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31.
OBJECTIVES: The Computer-Aided System for CArdiovascular Disease Evaluation (CASCADE) has been developed for streamlined, automated analysis of carotid artery magnetic resonance imaging to measure atherosclerotic plaque burden and composition in vivo. The purpose of this investigation was to assess the performance of CASCADE compared with manual outlining. METHODS: Magnetic resonance images were obtained from 26 subjects with 16% to 79% carotid artery stenosis by duplex ultrasound who were imaged twice in a 2-week period with a multiple-slice, multiple-contrast magnetic resonance imaging protocol as part of the Outcome of Rosuvastatin treatment on carotid artery atheroma: a magnetic resonance Imaging ObservatioN trial. Manual outlining was used to identify the boundaries of the lumen, wall, necrotic core (NC), and calcifications. After 6 months, the analysis was repeated using CASCADE. For each data set, the contours were used to compute the maximal normalized wall index (NWI; wall area divided by total vessel area), maximal wall thickness (WT), and the average NC and calcified (CA) areas per slice. Agreement between manual and automated reviews and the scan-scan measurement reproducibilities were evaluated. RESULTS: Pearson correlation between manual and automated analyses was 0.94 for maximal NWI, 0.86 for maximal WT, 0.84 for NC, and 0.96 for CA. Intraclass correlation coefficients for manual and automated analyses were 0.90 and 0.97 for maximal NWI, 0.89 and 0.95 for maximal WT, 0.95 and 0.87 for NC, and 0.96 and 0.94 for CA, respectively. CONCLUSIONS: Automated analysis tools are capable of providing accurate and reproducible measurements of carotid atherosclerotic burden and composition when compared with manually outlined results.  相似文献   
32.
The study examined how nap length, nap timing and sleep quality affect early morning performance (6:00 to 8:00). Twelve students participated in a simulated nightshift schedule (22:00 to 8:00) where the length and timing of nocturnal naps were manipulated (0:00-1:00, 0:00-2:00, 4:00-5:00 and 4:00-6:00). A performance test battery was administered consisting of a psychomotor vigilance test, a logical reasoning test, and a visual analogue scale for subjective fatigue and sleepiness. The results showed that a 120-min nap sustained early morning performance better than a 60-min nap. Taking a nap earlier or later did not affect the neurobehavioral performance tests, although participants slept more efficiently during naps later in the night shift. A negative effect of a nocturnal nap during the night shift on subsequent daytime and nocturnal sleep was not observed in the sleep architecture. It still remains unclear whether slow wave sleep plays an important role in sustaining early morning performance. In terms of work safety and sleep health, the results suggest that a longer and later nap is beneficial during night shifts.  相似文献   
33.
A 29-year old woman developed severe congestive heart failure in the first week after an uneventful full-term delivery. Despite intense medical treatment over the next 6 months, her heart failure symptoms gradually worsened and she eventually developed cardiogenic shock. She successfully underwent the implantation of a left ventricular assist system, but because there was no sign of recovery of ventricular function, she was placed on the waiting list for heart transplantation. After 143 days of support, she suffered from brain hemorrhage, and eventually died after a total of 321 days of left ventricular support. Postmortem examination of the myocardium showed sustained diffuse fibrosis and no inflammatory reaction. This case implies that with severe peripartum cardiomyopathy heart transplantation should be considered without delay even if a mechanical assist system is available.  相似文献   
34.
We report a male case of beta-catenin-activated hepatocellular adenoma (HCA) focusing on findings of gadoxetic-acid-enhanced magnetic resonance imaging (EOB-MRI) and discussing the molecular background and possible clinical significance. The patient was a 31-year-old man in whom computed tomography (CT) showed a large nodule of 14?cm in diameter in the right liver lobe. On dynamic contrast-enhanced CT, heterogeneous and slight to moderate enhancement was observed during the early phase, with washout in the late phase. Focal fat deposits and a scar-like portion in the lesion were also seen. Most of the lesion was slightly hyperintense compared with the background liver on the hepatobiliary phase of EOB-MRI. After operation, this patient was confirmed pathologically as having beta-catenin-activated HCA with a portion suggestive of malignant transformation. In addition, intense organic anion transporter polypeptide 8 expression was observed throughout the tumor by immunohistochemical staining.  相似文献   
35.
A bstract Background : In the repair of total anomalous pulmonary venous return (TAPVR) under cardiopulmonary bypass, esmolol, ultra short acting beta blocker, was applied to obtain low heart rate and weak ventricular contraction under mild hypothermic cardiopulmonary bypass. Methods : Five infants aged from 14 to 158 days with an average of 70 days, underwent a primary or palliative repair of TAPVR. The type of anomalous return was supracardiac type (2), infracardiac (2), and intracardiac (1). A primary repair was done in three for isolated TAPVR with bypass time of 65 to 76 minutes, and a palliative repair for two with complex anomalies with bypass time of 64 and 87 minutes. Results : There was one operative death from cerebral bleeding in an infant with complex TAPVR who underwent simultaneous pulmonary banding. Conclusion : This strategy seems to be applicable in pediatric cardiac surgery when aortic cross-clamping is better to be avoided and the surgery is mainly limited to the atrial level.  相似文献   
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37.
The aim of this study is to evaluate the effects of work improvements in small enterprises (WISE) on workloads and productivity, and managers' satisfaction with those projects. Participating in this study from 1994 to 1996 were 9 small enterprises, 3 metal industries, 1 car parts manufacturing, 1 garment manufacturing, 1 food processing, and a few others. Upon visiting these worksites, we carried out interviews on the implemented WISE improvements and made objective evaluations of their effect on workloads and productivity. Reductions in physical workloads were found in 4 of 6 enterprises where that factor was estimated. Productivity in most of the enterprises increased after WISE improvements. Managers' subjective satisfaction with WISE activity ranged between 50-80% on each technical item. More than 50 percent of managers came to understand the necessity of workers' involvement and understanding of the activities in order to sustain activity for improvement. WISE activity can exert a beneficial influence on workload and productivity. Most of the managers were satisfied with the results. It is presumed that follow-up visits with objective estimation will provide both managers and workers with encouragement to maintain their efforts.  相似文献   
38.
Most synovial cysts of the lumbar spine appear as intraspinal extradural masses adjacent to the facet joint. Almost all symptomatic synovial cysts are located within the spinal canal and or the neural foramen. To our knowledge, only 6 cases of symptomatic extraspinal synovial cysts have been described in the literature. The authors report a case of lumbar radiculopathy caused by a synovial cyst located in the far lateral extraforaminal area. The patient underwent decompression of the L5 nerve root with recapping right isthmectomy and facetectomy. Postoperative recovery was uneventful, and the patient was totally pain free with no motor deficit. Symptomatic synovial cysts are uncommon lesions that are associated with degenerative disease of the spine. Juxtafacet cysts should be considered in the differential diagnosis of space-occupying lesions at the extraforaminal areas. Recapping isthmectomy and facetectomy are useful procedures for a synovial cyst located in the far lateral extraforaminal area.  相似文献   
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40.
The occurrence of pelvic insufficiency fractures in patients with rheumatoid arthritis has not previously been well emphasized. These fractures are difficult to detect clinically, and appropriate radiological investigation is necessary for diagnosis. A 72-year-old woman with rheumatoid arthritis presented with severe left groin pain. Pelvic radiographs showed parasymphyseal fractures, and marked instability of these fractures was observed at the follow-up 2 weeks later. Computed tomographic scan of the sacrum showed a widened linear fracture gap in the left sacral ala. Because the patient's pain was so severe that she could not change position, external fixation was performed to achieve rapid pain relief and early mobilization. Although most patients with these fractures respond well to simple conservative treatments, parasymphyseal fractures combined with sacral fractures may cause disruption of the pelvic ring and occasionally need operative management.  相似文献   
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