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1. Patterns of species richness and species assemblage composition of ground‐dwelling arthropods in primary successions along glacier forelands are traditionally described using a taxonomic approach. On the other hand, the functional trait approach could ensure a better characterisation of their colonisation strategies in these types of habitat. 2. The functional trait approach was applied to investigate patterns of functional diversity and life‐history traits of ground beetles and spiders on an alpine debris‐covered glacier and along its forefield in order to describe their colonisation strategies. 3. Ground beetles and spiders were sampled at different successional stages, representing five stages of deglaciation. 4. The results show that the studied glacier hosts ground beetle and spider assemblages that are mainly characterised by the following traits: walking colonisers, ground hunters and small‐sized species. These traits are typical of species living in cold, wet, and gravelly habitats. The diversity of functional traits in spiders increased along the succession, and in both carabids and spiders, life‐history traits follow the ‘addition and persistence model’. Accordingly, there is no turnover but there is an addition of new traits and a variation in their proportion within each species assemblage along the succession. The distribution of ground beetles and spiders along the glacier foreland and on the glacier seems to be driven by dispersal ability and foraging strategy. 5. The proposed functional approach improves knowledge of the adaptive strategies of ground‐dwelling arthropods colonising glacier surfaces and recently deglaciated terrains, which represent landforms quickly changing due to global warming.  相似文献   
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In this paper, isozymes have been used for the first time astools to aid identification of someCurcuma L. species that arestill taxonomically confused. These markers were employed toconfirm the taxonomic identification and to distinguish thetaxa analysed; the results were used to describe the relationshipwithin the early-flowering group. Twenty-one isozymes were initiallytested; out of these, eight isozymes showed reliable polymorphismto distinguish between the taxa analysed. Patterns from isozymedata were analysed using cluster analysis and UPGMA to producea dendrogram depicting the degree of relationship among thespecies. Copyright 1999 Annals of Botany Company Curcuma, Zingiberaceae, isozymes, species identification.  相似文献   
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ABSTRACT. The sesquiterpenoid euplotin C is a secondary metabolite produced by the ciliated protist Euplotes crassus and provides a mechanism for damping populations of potential competitors. Indeed, E. crassus is virtually resistant to its own product while different non-producer species representing an unbiased sample of the marine, interstitial, ciliate diversity are sensitive. For instance, euplotin C exerts a marked disruption of different homeostatic mechanisms in Euplotes vannus . We demonstrate by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay that euplotin C quickly decreases viability and mitochondrial function of E. vannus with a very high efficacy and at micromolar potency. In addition, euplotin C induces apoptosis in E. vannus as 4,6-diamino-2-phenylindole and terminal transferase dUTP nick end labeling staining show the rapid condensation and fragmentation of nuclear material in cells treated with euplotin C. These effects occur without detectable permeabilisation or rupture of cell membranes and with no major changes in the overall morphology, although some traits, such as vacuolisation and disorganized microtubules, can be observed by transmission electron microscopy. In particular, E. vannus show profound changes of the mitochondrial ultrastructure. Finally, we also show that caspase activity in E. vannus is increased by euplotin C. These data elucidate the pro-apoptotic role of euplotin C and suggest a mechanism for its impact on natural selection.  相似文献   
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Epidermal levels of enzymatic and non-enzymatic antioxidants such as superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GSH-Px), vitamin E (Vit E), ubiquinol (CoQ10H2), and reduced glutathione (GSH), as well as polyunsaturated fatty acids of phospholipids (PL-PUFA), were evaluated in the affected epidermis of 15 patients with active vitiligo (AVP) and in the corresponding epidermis of 15 healthy phototype matched controls. The epidermal levels of CoQ10H2, Vit E, GSH, and CAT activity were significantly reduced in AVP and were associated with a marked increase of oxidized glutathione, whereas SODs and GSH-Px activities and ubiquinone concentration remained similar to control values. Antioxidant deficiency, in particular the decline of lipophilic antioxidants, i. e., CoQ10H2 and Vit E, accounts well for PL-PUFA reduction observed in vitiligo epidermis, mainly affecting C18: 3 n-3, C20: 3 n-6, C20: 4 n-6, and C22: 6 n-3 fatty acids and suggesting the occurrence of a lipoperoxidative process. In conclusion, both an imbalance of the intracellular redox status and a significant depletion of enzymatic and non-enzymatic antioxidants feature the epidermis of AVP, and represent a fingerprint of an abnormal oxidative stress leading to epidermal cell injury.  相似文献   
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We characterized eight polymorphic microsatellites in the Scotia icefish Chaenocephalus aceratus (Perciformes, Notothenioidei, Channichthyidae) that is endemic of Southern Ocean waters surrounding the tip of the Antarctic Peninsula. Microsatellites were isolated from a partial genomic library enriched for an AC motif. The number of alleles ranged from two to 19 with a mean observed hererozygosity of 0.71. Loci were in Hardy–Weinberg equilibrium and no evidence for linkage disequilibrium was found. These molecular markers will be useful to investigate Scotia icefish genetic structure, possibly providing insights on its effective population size and demographic history.  相似文献   
6.
Seven polymorphic microsatellite loci were isolated and characterized from the grapsid crab Pachygrapsus marmoratus using FIASCO (fast isolation by AFLP of sequences containing repeats) protocol. Twenty‐seven primer pairs were designed, 14 of which worked well in polymerase chain reaction (PCR), amplifying a fragment of the expected size. Variability was tested in 18 specimens collected along the coast of Tuscany (Italy). Five loci were discarded due to stutter products during their amplification, and two resulted to be monomorphic. The remaining seven loci, showed a number of alleles ranging from two to 14 and an observed heterozygosity ranging from 0.12 to 0.67.  相似文献   
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The four existing species of the ascophoran bryozoan Pentapora Fisher, 1807 are revised, and two new fossil species are introduced: Pentapora lacryma sp. nov. from the Pliocene Coralline Crag Formation of Suffolk, and Pentapora clipeus sp. nov. from the Pliocene of Emilia, Italy. The Arctic species Pentapora boreale Kuklinski & Hayward possesses a lyrula, does not belong in Pentapora, and is a junior synonym of Raymondcia rigida (Lorenz). The morphology of the autozooids is relatively uniform within the genus, and the main distinguishing characters are those of the ovicells and, particularly, the giant avicularia that are developed sporadically in all species apart from Pentapora foliacea, popularly known as ‘Ross coral’. A phylogenetic analysis based on skeletal characters returned a single shortest tree in which the three species of Pentapora from the North Atlantic (P. foliacea, Pentapora pertusa, and P. lacryma sp. nov. ) form a clade crownward of the three basal species from the Mediterranean (Pentapora ottomulleriana, Pentapora fascialis, and P. clipeus sp. nov. ). © 2010 The Linnean Society of London, Zoological Journal of the Linnean Society, 2010, 160 , 17–39.  相似文献   
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