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131.
Helical CT of the liver: value of an early hepatic arterial phase   总被引:9,自引:0,他引:9  
Bonaldi  VM; Bret  PM; Reinhold  C; Atri  M 《Radiology》1995,197(2):357
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Correlation of magnetic resonance (MR) images with cryomicrotome sections and formalin-fixed sections of human brain documents that spin-echo MR imaging with short repetition time/short echo time pulse sequences can display the surface gyri of the inferomedial temporal lobe, including the temporal pole, the parahippocampal gyrus, the isthmus of the cingulate gyrus, the lateral and medial occipitotemporal gyri, and the inferior temporal gyrus; the associated sulci including the rhinal and collateral sulci, the occipitotemporal sulcus, and the anterior calcarine sulcus; the components and fiber tracts of the hippocampal formation including the pes hippocampi, the hippocampus, the subiculum, the dentate gyrus, the subsplenial gyri, the alveus, the fimbria, and the fornix; the fissures and sulci associated with the hippocampal formation, including the hippocampal fissure, dentatofimbrial fissure, and the choroidal fissure; the continuity between the cingulate gyrus and the parahippocampal gyrus through the isthmus of the cingulate gyrus; and the continuity between the callosal sulcus and the hippocampal fissure.  相似文献   
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BACKGROUND: Platelet concentrates and apheresis platelets must be maintained at a temperature as close as possible to 20 to 24 degrees C during transport. To improve temperature control, ensure component quality, and meet handling and freight carrier needs, a new insulated shipping container system was developed and evaluated. STUDY DESIGN AND METHODS: Molded polyurethane-insulated shipping containers were loaded with different payloads of simulated platelet components, with or without gel-based temperature stabilizing packs (TSPs). The containers were subjected to constant ambient temperature of 37, 4 or -10 degrees C. Payload temperatures were continuously monitored, in situ, for 24 hours. RESULTS: Temperature data are reported as the mean number of hours needed for components to warm or cool by 1 degree C. The temperature of payloads exposed to a constant 37 degrees C ambient temperature increased by 1 degree C in 2.5 to 3.8 hours when no TSPs were included in the shipment and in 6.1 to 6.9 hours when TSPs were used. Exposure to a constant 4 degrees C ambient temperature resulted in a 1 degree C temperature decrease in 1.8 to 3.4 hours without TSPs and in 4.6 to 5.6 hours with TSPs. At a -10 degrees C ambient temperature, there was a 1 degree C drop within 1.0 to 1.6 hours without TSPs and within 2.7 to 2.9 hours with TSPs. CONCLUSION: The container and packing methods described moderate the rate of change in the temperature of platelet components during their exposure to challenging ambient conditions. The use of TSPs substantially improves the performance of the system. In addition, the system meets freight carrier requirements and is easy to use, environmentally friendly, and durable.  相似文献   
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The cervical aortic arches   总被引:2,自引:0,他引:2  
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This paper assesses the impact of medical care on changes in mortality in east Germany and Poland before and after the political transition, with west Germany included for comparison. Building upon Rutstein's concept of unnecessary untimely deaths, we calculated the contribution of conditions considered responsive to medical care or health policy to changes in life expectancy between birth and age 75 [e(0-75)] for the periods 1980/1983-1988 and 1991/1992-1996/1997.Temporary life expectancy, between birth and age 75, has been consistently higher in west Germany, intermediate in east Germany and lowest in Poland. Although improving in all three regions between the early 1980s and the late 1990s, the pace of change differed between countries, resulting in a temporary widening of an initial east-west gap by the late 1980s and early 1990s. In the 1980s, in east Germany, 50-60% of the improvement was attributable to declining mortality from conditions responsive to medical care (west Germany: 30-40%). A net positive effect was also observed in Poland, although counterbalanced by deterioration in ischaemic heart disease mortality.In the former communist countries, improvements attributable to medical care in the 1980s were due, largely, to declining infant mortality. In the 1990s, they benefited also adults, specifically those aged 35+ in Poland and 55+ in Germany. A persisting east-west gap in temporary life expectancy in Germany was due, largely, to higher mortality from avoidable conditions in the east, with causes responsive to health policy contributing about half, and medical care 16% (men) to 24% (women) to the differential in 1997.The findings indicate that changes in the health care system related to the political transition were associated with improvements in life expectancy in east Germany and, to a lesser extent, in Poland. Also, differences in the quality of medical care as assessed by the concept of "unnecessary untimely deaths" appear to contribute to a persisting east-west health gap. Especially in Poland and the former German Democratic Republic there remains potential for further progress that would narrow the health gap with the west.  相似文献   
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