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41.
G. Ragone R. Caizzi R. Moschetti P. Barsanti V. De Pinto C Caggese 《Molecular genetics and genomics : MGG》1999,261(4-5):690-697
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Carsten Nesshöver Marie Vandewalle Heidi Wittmer Estelle V. Balian Esther Carmen Ilse R. Geijzendorffer Christoph Görg Rob Jongman Barbara Livoreil Luis Santamaria Stefan Schindler Josef Settele Isabel Sousa Pinto Katalin Török Jiska van Dijk Allan D. Watt Juliette C. Young Klaus Peter Zulka the KNEU Project Team 《Biodiversity and Conservation》2016,25(7):1215-1233
The absence of a good interface between scientific and other knowledge holders and decision-makers in the area of biodiversity and ecosystem services has been recognised for a long time. Despite recent advancements, e.g. with the Intergovernmental Platform on Biodiversity and Ecosystem Services (IPBES), challenges remain, particularly concerning the timely provision of consolidated views from different knowledge domains. To address this challenge, a strong and flexible networking approach is needed across knowledge domains and institutions. Here, we report on a broad consultation process across Europe to develop a Network of Knowledge on biodiversity and ecosystem services (NoK), an approach aiming at (1) organising institutions and knowledge holders in an adaptable and responsive framework and (2) informing decision-makers with timely and accurate biodiversity knowledge. The consultation provided a critical analysis of the needs that should be addressed by a NoK and how it could complement existing European initiatives and institutions at the interface between policy and science. Among other functions, the NoK provides consolidated scientific views on contested topics, identification of research gaps to support relevant policies, and horizon scanning activities to anticipate emerging issues. The NoK includes a capacity building component on interfacing activities and contains mechanisms to ensure its credibility, relevance and legitimacy. Such a network would need to ensure credibility, relevance and legitimacy of its work by maximizing transparency and flexibility of processes, quality of outputs, the link to data and knowledge provision, the motivation of experts for getting involved and sound communication and capacity building. 相似文献
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De Luca A Gallo M Aldinucci D Ribatti D Lamura L D'Alessio A De Filippi R Pinto A Normanno N 《Journal of cellular physiology》2011,226(8):2131-2138
Increasing evidence suggests that bone marrow-derived mesenchymal stem cells (MSCs) are recruited into the stroma of developing tumors where they contribute to cancer progression. MSCs produce different growth factors that sustain tumor-associated neo-angiogenesis. Since the majority of carcinomas secrete ligands of the epidermal growth factor receptor (EGFR), we assessed the role of EGFR signaling in regulating the release of angiogenic factors in MSCs. Treatment of human primary MSCs and of the human osteoblastic cell line hFOB with transforming growth factor α (TGF-α), one of the main ligands of the EGFR, significantly induced activation of this receptor and of different intracellular signaling proteins, including the PI3K/AKT and the MEK/MAPK pathways. TGF-α induced a significant increase in the levels of secretion of vascular endothelial growth factor in both MSCs and hFOB. Conditioned medium from TGF-α treated MSCs showed an higher in vivo angiogenic effect as compared with medium from untreated cells. Treatment of MSCs with TGF-α also produced a significant increase in the secretion of other angiogenic growth factors such as angiopoietin-2, granulocyte-colony stimulating factor, hepatocyte growth factor, interleukin (IL)-6, IL-8, and platelet-derived growth factor-BB. Using selective MEK and PI3K inhibitors, we found that both MEK/MAPK and the PI3K/AKT signaling pathways mediate the ability of TGF-α to induce secretion of angiogenic factors in MSCs. Finally, stimulation with TGF-α increased the ability of MSCs to induce migration of MCF-7 breast cancer cells. These data suggest that EGFR signaling regulates the ability of MSCs to sustain cancer progression through the release of growth factors that promote neo-angiogenesis and tumor cell migration. 相似文献
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A new, simple and rapid procedure for the purification of high amounts of mitochondrial porins from different tissues of mammalia is described. The method consists in a single step hydroxyapatite / celite chromatography of Triton X-100 solubilized mitochondrial membranes. For optimal purification several factors are critical such as the absence of salts, a low protein / detergent ratio and an exact hydroxyapatite / celite ratio of 2:1. 相似文献
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Isolated rat hearts perfused with Chenoweth-Koelle solution exhibit tachyphylaxis to tyramine. This tachyphylaxis was prevented if tyrosine was included in the perfusion solution. Other amino acids, including glycine, serine, phenylalanine, valine, tryptophan, glutamate, aspartate, arginine, lysine and
-tyrosine, failed to prevent the tyramine-induced tachyphylaxis. Hearts from reserpinized animals showed increased chronotropy after tyramine only when tyrosine was present in the medium. This response could be blocked by
, m-hydroxybenzyl-hydrazine and d,l-propanolol, indicating that it was mediated by the synthesis and release of catecholamines. These experiments suggest that sympathetic nerves in the isolated rat heart exhibit a requirement for tyrosine when catecholamine release is enhanced. 相似文献
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Phytoplankton morphological response to the underwater light conditions in a vegetated wetland 总被引:2,自引:3,他引:2
This study analyses the influence of the underwater light climate on the morphometric characteristics of the phytoplankton
at the population and community levels. The differences in light conditions across the floodplain were mainly defined by the
patchiness of floating macrophytes and humic acids concentration. A morphometric response at the community level to the underwater
PAR was registered. Sites with strong light constraints were characterised by non-flagellated organisms or with a small proportion
of unicellular flagellates. Short organisms (<10 μm) with a unit volume of less than 1,000 μm3 and a high surface:volume ratio (S/V >2) were the morphotypes related to poorly illuminated environments. Moreover, the organisms
showed forms more slender under these limiting conditions. This pattern was different to that registered in well-illuminated
sites where longer and larger organisms, with a smaller S/V and frequently flagellated, coexisted with the previously mentioned
organisms. The autotrophic picoplankton, the smallest phytoplankton fraction, revealed lower abundances at sites with higher
humic substances. Short term morphological changes were additionally studied for the dominant species by means of mesocosm
experiments simulating different light climates. Intraspecific morphological plasticity was observed with respect to the filament
length and the vacuolization of cells.
Electronic Supplementary Material Supplementary material is available for this article at and is available to authorized users. 相似文献
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