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141.
The decrease in the respiratory control ratio of mitochondria is a first order process when these organelles are incubated in isotonic sucrose. Furthermore, the initial respiratory control ratios and the rates of loss in respiratory control in liver mitochondria from rats hosting the Walker 256 carcinoma are not significantly different form the same properties of mitochondria from untreated animals. 相似文献
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143.
Differences in Rh type between age groups of leukaemia patients 总被引:1,自引:0,他引:1
F V De George 《Nature》1970,228(5267):168-169
144.
假设文献[1]中的各个企业之间除了在库存管理方面进行合作外,还没有意识到在市场广告和供应链生产方面的合作,企业处于分别决策状态,每一个企业最大化其自身的利润。在给出考虑广告和产品结构的供应商管理库存系统的Nash非合作博弈模型,分析博弈结果和一些性质。最后给出一个算例说明本文的理论。 相似文献
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147.
George B. Pendlebury 《西北部美国博物学家》2011,36(1)
A second record of the long-nosed snake in Idaho was taken at the entrance to Bruneau Dunes State Park, Owghee County 相似文献
148.
Studies of Great Basin faunas can provide information for landscape-level adaptive management by federal agencies and shed light on potential effects of climate change in continental interior landscapes. To provide such information, we characterized the butterfly fauna of the Toquima Range, a mountain range in the heart of the Great Basin with topography typical of the region. We also compared the butterfly fauna of the Toquima Range to that of the adjacent Toiyabe Range, which is more topographically complex and species rich but less representative of the Great Basin on the whole. We explicitly addressed the effects of area and water availability on butterfly species richness. Butterfly species presence data were compiled for 14 canons and 1 peak in the Toquima Range. Data from 11 canyons that we inventoried systematically were amenable to statistical analysis. Eighty butterfly species (59 residents) have been recorded from the Toquima Range since 1935. By comparison, 99 species have been recorded from the Toiyabe Range. Mean canyon-level butterfly species richness was significantly lower in the Toquima Range than in the Toiyabe Range. This difference cannot be explained by differences in canyon size between mountain ranges. Within the Toquima Range water availability seems to have a dominant effect on butterfly species richness. Between mountain ranges species richness is influenced by interactions among areas, moisture, and topography. These data should assist managers in developing guidelines for conservation planning in the Great Basin. 相似文献
149.
SuiYan Fu QuanQi Shi Chi Wang George Parks Ling Zheng Hao Zheng WeiJie Sun 《科学通报(英文版)》2011,56(12):1182-1187
A research topic of great interest to the space physics community is the observation of plasmas flowing at hundreds of kilometers
per second in the Earth’s plasma sheet. Although considerable effort has been made to understand the source of fast-flowing
plasmas, many questions remain unanswered about the mechanisms that produce high-speed flows and the effects they have on
magnetospheric disturbances, especially their contributions to magnetospheric convection and substorms. In this paper, we
discuss briefly the history of high-speed flows and review the proposed mechanisms, signatures of high-speed flows in auroras
and their interaction with the background plasma. We then summarize the relationships between high-speed flows and magnetic
structures, discuss questions associated with substorms, and finally pose several important scientific questions that need
to be addressed. 相似文献
150.
Somatic coding mutations in human induced pluripotent stem cells 总被引:2,自引:0,他引:2