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Hoffmann M Hilton-Taylor C Angulo A Böhm M Brooks TM Butchart SH Carpenter KE Chanson J Collen B Cox NA Darwall WR Dulvy NK Harrison LR Katariya V Pollock CM Quader S Richman NI Rodrigues AS Tognelli MF Vié JC Aguiar JM Allen DJ Allen GR Amori G Ananjeva NB Andreone F Andrew P Aquino Ortiz AL Baillie JE Baldi R Bell BD Biju SD Bird JP Black-Decima P Blanc JJ Bolaños F Bolivar-G W Burfield IJ Burton JA Capper DR Castro F Catullo G Cavanagh RD Channing A Chao NL Chenery AM Chiozza F Clausnitzer V 《Science (New York, N.Y.)》2010,330(6010):1503-1509
Using data for 25,780 species categorized on the International Union for Conservation of Nature Red List, we present an assessment of the status of the world's vertebrates. One-fifth of species are classified as Threatened, and we show that this figure is increasing: On average, 52 species of mammals, birds, and amphibians move one category closer to extinction each year. However, this overall pattern conceals the impact of conservation successes, and we show that the rate of deterioration would have been at least one-fifth again as much in the absence of these. Nonetheless, current conservation efforts remain insufficient to offset the main drivers of biodiversity loss in these groups: agricultural expansion, logging, overexploitation, and invasive alien species. 相似文献
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Prodip K. Roy Wilmar Maarisit Michael C. Roy Junsei Taira Katsuhiro Ueda 《Marine drugs》2012,10(12):2741-2748
Five new diterpenoids 1–5 were isolated from an Okinawan soft coral, Cespitularia sp., together with the known diterpenoid, alcyonolide (6). New diterpenoid structures were elucidated by spectroscopic methods and by comparison of their NMR data with those of related compounds. Alcyonolide (6) was cytotoxic against HCT 116 cells (IC50 5.85 μM), while these new diterpenoids 1–5 were much less active (IC50 28.2–91.4 μM). 相似文献
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Summary A technique for the in vitro culture of embryos of Brussels sprouts (Brassica oleracea L. var. gemmifera) is described. It has been possible to grow the material at all embryonic stages, ranging from the Pre-heart to Mature, into normal seedlings. Pre-heart and Heart-stage embryos require coconut milk for growth. After a short period of growth on a medium containing coconut milk, the embryos have to be transferred to a simpler medium.Growth substances as well as sucrose are needed for the growth of Torpedo and Walking-stick embryos. When the embryos have sufficiently advanced in differentiation (Mature I and older) to germinate (i.e. to form roots) they can grow on a simple inorganic medium. The uniformity of the plants grown from in vitro embryo cultures and the percentage of success are generally high. The usefulness of the technique for obtaining seedlings early in spring for breeding purposes is discussed. 相似文献
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