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Linaria arabiniana sp. nov. is described from coastal sand dunes of a very reduced area in Alicante Province (south-eastern part of the Iberian Peninsula). It is a perennial herb characterized by its 3–4-verticillate leaves, glabrous stems, large violet or rarely yellow flowers, and bicoloured usually flat seeds. Morphological characteristics and taxonomic affinities of this taxon are discussed, as are data on its ecology, phytosociology, and eventual conservation features.  相似文献   
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This paper describes the diet of young Lammergeiers Gypaetus barbatus during the nesting period on the island of Corsica. From 1985 to 1990, food items were collected from 10 nests after the young had fledged. These nests were from five territories where the potential food supply was estimated using a range of 'large mammal' counts. Feathers, bones and isolated hooves were used to identify prey. For each nest, the minimal number of food portions was quantified, ignoring material that provided no food value. The diet consisted mainly of limb extremities of domestic ungulates (c. 36% by number of portions of sheep and goat; 33% of cattle, mostly calves). Pigs, both wild and domestic, yielded c. 16% of the items. Where present on the territory, mouflon occurred frequently in nests (c. 12% of items). Birds and small mammals were scarce in the diet. For three territories, samples varied less among years than among territories. There was a strong association between the diet of the young and the food available in the territories. We examined the possible links between known 20th century changes in stock rearing activities and the Corsican Lammergeier's diet.  相似文献   
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The aim of the present work is to detect possible differencesin the chromatin of plants replicated in the absence of proteinsynthesis. The kinetics of nuclease digestion in Allium cepa L., evaluatedafter making the cells permeable, was faster for the chromatinof meristem cells replicated in the presence of 1.0 µgml–1 cycloheximide than in control cells. In order to have a synchronous population in the meristems,cells were labelled as binucleate by a short treatment with5.0 mM caffeine. Treated cells failed to increase both theircontent in dense chromatin and intranuclear histones. Thesefacts suggest that chromatin replicated in the presence of cycloheximidedid not incorporate histones and was unable to be integratedinto dense chromatin patches. Key words: Allium cepa L., Chromatin replication, Protein synthesis  相似文献   
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