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排序方式: 共有648条查询结果,搜索用时 31 毫秒
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Great tits can reduce caterpillar damage in apple orchards 总被引:3,自引:0,他引:3
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Renaud-Gentié Christel Dieu Valentin Thiollet-Scholtus Marie Mérot Anne 《The International Journal of Life Cycle Assessment》2020,25(7):1307-1322
The International Journal of Life Cycle Assessment - Consumer demand and state incentives in certain EU countries are driving the rapid development of organic viticulture. However, compared with... 相似文献
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The locus (IP2) for the hereditary form of incontinentia pigmenti (IP) has been mapped to Xq28 by linkage analysis. We studied three IP families with polymorphic markers in the Xq28 region. In two families we observed recombination between the marker loci and IP. In the third family no crossing overs were seen and linkage to the Xq28 region could not be excluded. The other IP locus (IP1) has been mapped to Xp 11.21, because of sporadic cases of IP with X-chromosomal alterations involving Xp11.21. To check whether this locus is linked to IP in these families, we used polymorphic markers in the Xp11 region. In all three families recombinations were observed, thus excluding linkage to this locus in these IP families. 相似文献
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Johan Verbeeck Christel Faes Thomas Neyens Niel Hens Geert Verbeke Patrick Deboosere Geert Molenberghs 《Biometrics》2023,79(1):417-425
The Corona Virus Disease (COVID-19) pandemic has increased mortality in countries worldwide. To evaluate the impact of the pandemic on mortality, the use of excess mortality rather than reported COVID-19 deaths has been suggested. Excess mortality, however, requires estimation of mortality under nonpandemic conditions. Although many methods exist to forecast mortality, they are either complex to apply, require many sources of information, ignore serial correlation, and/or are influenced by historical excess mortality. We propose a linear mixed model that is easy to apply, requires only historical mortality data, allows for serial correlation, and down-weighs the influence of historical excess mortality. Appropriateness of the linear mixed model is evaluated with fit statistics and forecasting accuracy measures for Belgium and the Netherlands. Unlike the commonly used 5-year weekly average, the linear mixed model is forecasting the year-specific mortality, and as a result improves the estimation of excess mortality for Belgium and the Netherlands. 相似文献
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Pascal Tomakidi Nicolae Mirancea Norbert E. Fusenig Christel Herold-Mende Franz Xaver Bosch D. Breitkreutz 《Differentiation; research in biological diversity》1999,64(5):263-275
Benign and malignant HaCaT-ras clones, derived from immortalized HaCaT cells were grown as nude mouse surface transplants rendering a human tumor progression model. Searching for malignancy-related alterations, the deposition, localization and mRNA of basement membrane and hemidesmosome components were analysed by immunofluorescence, in situ hybridization and electron microscopy. Initially, at 1 week epithelia of benign and malignant cells revealed a similarly low polarity and an enlarged 'activated basal' compartment, reflected by partial dislocation and extended pericellular staining of the hemidesmosome constituent integrin alpha 6 beta 4 seen by immunofluorescence. Whereas benign grafts eventually normalized, closely resembling grafts of HaCaT cells, malignant growth was correlated with a persisting epithelial activation state and continuing higher expression of alpha 6 (by immunofluorescence and in situ hybridization). The basement membrane components bullous pemphigoid antigen 1, laminin-5 and collagen IV exhibited a largely linear distribution at 1 week. However, in the malignant cell transplants initially minor basement membrane discontinuities became more severe at around 2 weeks, associated with close stromal cell contacts, angiogenesis and invasion. Most striking were basement membrane alterations seen by electron microscopy. At 1 week stretches of basement membrane had developed in malignant transplants, though to a much lesser extent than in benign specimens. With invasion these basement membrane structures mostly disappeared despite persistent although variable immunofluorescence, suggesting high turnover without ultrastructural assembly. The hemidesmosome structures were defective throughout, completely lacking anchoring plaques with keratin filaments, whereas they were still associated with basement membrane deposits. Thus, malignant HaCaT-ras transplants, while initially resembling regenerating wounds, revealed an increasing loss of tissue polarity and basement membrane structures, which seemed to be accelerated upon stromal cell contacts. 相似文献
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Christel Elvestad 《Ocean Development & International Law》2013,44(3):241-255
The European Union Regulation on Illegal, Unreported, and Unregulated (IUU) Fishing, aimed at excluding illegally caught fish from its market, is a comprehensive instrument with strict control measures and the possibility of trade sanctions. It has been criticized as being ineffective due to regulatory shortcomings and a lack of enforcement. This article offers an alternative perspective, focusing on the dynamic relationship between soft and hard forms of enforcement. The regulation has produced important results in the fight against IUU fishing by promoting improved flag state performance. 相似文献