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排序方式: 共有204条查询结果,搜索用时 15 毫秒
1.
Accelerated tissue expansion with the "overfilling" technique 总被引:3,自引:0,他引:3
J P Pietil? R E Nordstr?m P J Virkkunen P E Voutilainen A E Rintala 《Plastic and reconstructive surgery》1988,81(2):204-207
Temporary overexpansion of the tissues at each filling session increased the actual inflation volume by about 59 percent. This shortened the process of tissue expansion considerably. "Overexpansion" means that the pressure in the expander is increased to a point where the dermal capillary flow is zero or the patient experiences so much discomfort that inflation cannot be carried out any further. The pressure in the expander is thereafter gradually decreased by taking out saline until both the capillary refill and all other clinical criteria are sufficient for safe dermal circulation. Comparison of the expander volume at the final pressure to the initial filling volume at the same pressure before the "overfilling" confirmed an average gain of about 59 percent in 14 patients. 相似文献
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Acetate Degradation at 70°C in Upflow Anaerobic Sludge Blanket Reactors and Temperature Response of Granules Grown at 70°C 下载免费PDF全文
Anaerobic acetate degradation at 70°C and at 55°C (as a reference) was studied by running laboratory upflow anaerobic sludge blanket (UASB) reactors inoculated with mesophilic granular sludge. In UASB reactors fed with acetate-containing media (3 g of chemical oxygen demand [COD] per liter, corresponding to 47 mM acetate) approximately 50 days was needed at 70°C and less than 15 days was needed at 55°C to achieve an effluent COD of 500 to 700 mg/liter. In the UASB reactors at both 70 and 55°C up to 90% of the COD was removed. Batch assays showed that sludges from two 70°C UASB reactors, one run at a low effluent acetate concentration and the other run at a high effluent acetate concentration, exhibited slightly different responses to temperatures in the range from 37 to 70°C. Both 70°C sludges, as well as the 55°C sludge, produced methane at temperatures of 37 to 73°C. The 55°C sludge exhibited shorter lag phases than the 70°C sludges and higher specific methane production rates between 37 and 65°C. 相似文献
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This study focused on the use of thermophilic anaerobic granulae in the start-up of 70°C acetate-fed upflow anaerobic sludge-blanket (UASB) reactors and the kinetics of granulae grown at 70°C. In the UASB reactors, chemical oxygen demand removal commenced within 48 h of the start-up. The maximum reduction in chemical oxygen demand was 84% with the feed containing yeast and 71% without a yeast supplement. In the bioassays, the yeast-grown sludge converted 98% of the acetate consumed to methane as compared to 92% for the sludge grown without yeast. The highest initial specific methane production rate (µCH
4) of the UASB sludges grown at 70°C was 0.088 h–1 at an acetate concentration of 4.6 mM. The higher initial acetate concentration was found to prolong the lag-phase in methane production significantly and to decrease the µCH
4. The half-saturation constant (K
s), the inhibition constant (K
i), the inhibition response coefficient (n), and the µCH
4
max, calculated according to a modified Haldane equation, were 1.5 mM, 2.8 mM, 0.8, and 0.28 h–1, respectively. The prolonged starvation of the 70°C sludge (15 days) decreased the µCH
4 from about 0.022 h–1 to 0.011 h–1 and increased the lag phase in methane production from 6 h to 24 h as compared to non-starved sludge. 相似文献
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C Crone J Frokjaer-Jensen JJ Friedman O Christensen 《The Journal of general physiology》1978,71(2):195-220
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Hannu Pöysä Jukka Rintala Aleksi Lehikoinen Risto A. Väisänen 《European Journal of Wildlife Research》2013,59(2):245-256
Populations of migratory species have undergone dramatic changes in recent decades, but little is known about the factors actually driving those changes. Of particular concern are quarry species such as migratory ducks (Anatidae), many of which have an unfavourable conservation status in Europe. By including both quarry and non-quarry species, as well as habitat preference and life history characteristics of the species, we investigated the relative importance of hunting pressure, both in Finland and at the European level, in explaining population changes of 16 species of migratory waterbirds in Finland during 1986–2011. Ban of lead shot in 1996 resulted in considerably lower annual hunting bags in Finland thereafter. Species which had the highest hunting pressure had the most negative slopes in population trends from 1986 up to 1997, suggesting that hunting probably limited those populations. However, in general population trends of the species were not strongly associated with hunting pressure in Finland or in Europe. Nor were basic life history characteristics (body mass and clutch size) associated with population trends of the species. In contrast, recent population declines were associated with habitat preferences of the species: those breeding mainly in eutrophic lakes had more negative population trends than those breeding in oligotrophic lakes or generalist species. Reasons for the relatively poor status of species preferring eutrophic lakes probably include over-eutrophication of nutrient-rich lakes, resulting in less abundant food resources, and increased nest depredation. 相似文献