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81.
The nymphalid butterfly tribe Preponini includes some of the Neotropical region's most spectacular and familiar butterflies, but the taxonomy of the group nevertheless remains unstable. Several recent studies of Nymphalidae phylogeny have suggested that both the tribe itself and several genera might not be monophyletic, but to date taxon sampling has not been sufficiently comprehensive to allow informed revision of the group's systematics. We therefore conducted the first complete species‐level phylogenetic study of the tribe to establish a firm higher classification. We used DNA sequence data from three genes, the two mitochondrial genes cytochrome oxidase subunits I and II (COI and COII), and the nuclear gene elongation factor‐1α (EF‐1α), to reconstruct the phylogeny of the tribe using maximum likelihood (ML), maximum parsimony (MP) and Bayesian inference (BI). We included 48 individuals representing the 22 recognised Preponini species, and an additional 25 out‐group taxa to explore taxonomic limits at different levels. Firstly, we found that Anaeomorpha splendida Rothschild never grouped with remaining Preponini, so that maintaining monophyly of the tribe requires the taxon to be excluded, and we thus reinstate the tribe Anaeomorphini stat.rev. Secondly, we investigated generic limits, in particular the relationship of Noreppa Rydon to Archaeoprepona Fruhstorfer, and that of Agrias Doubleday to Prepona Boisduval. The molecular results coupled with previous morphological studies suggest that Noreppa syn.n should be synonymised with Archaeoprepona, and that Agrias syn.n should be synonymised with Prepona. We found Prepona pheridamas (Cramer) to be sister to all other Prepona, and markedly divergent from them in both morphology and DNA sequences, suggesting the possibility that it should be placed in a separate genus. We also found a number of cases of significant DNA sequence divergence and paraphyly or polyphyly within putative species that require further taxonomic attention, including Prepona claudina (Godart) stat.n. and Prepona narcissus (Staudinger) stat.n., Prepona pylene Hewitson and Prepona deiphile (Godart). Future research should focus on a broader population sampling of widespread, polymorphic Preponini species to thoroughly revise the current species‐level taxonomy, thus creating a solid foundation for studies in ecology and conservation. 相似文献
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MERCIVAL R. FRANCISCO PEDRO M. GALETTI H. LISLE GIBBS 《Molecular ecology resources》2004,4(4):758-760
We designed primers for amplifying 11 polymorphic microsatellite loci in the blue manakin, Chiroxiphia caudata, a neotropical passerine bird which inhabits a critically endangered tropical ecosystem, the Brazilian Atlantic forest. Based on genotypes from 24 individuals from a single population, we detected between four and 22 alleles per locus with observed heterozygosities ranging from 0.54 to 0.92. These highly variable loci will be useful for determining levels of population differentiation and assessing the impact of habitat fragmentation on levels of genetic variation in isolated populations of these birds. 相似文献
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The goal of the present study was to obtain valuable microsatellite markers useful in genetic approaches of the shrimp Litopenaeus vannamei, an important aquaculture species of the world. Eight loci produced suitable polymorphic patterns with allele number ranging from two to 12 and expected heterozygosity from 0.18 to 0.89. Cross‐species amplification was successfully performed in five other penaeid species (Litopenaeus schmitti, Farfantepenaeus brasiliensis, Farfantepenaeus paulensis, Xiphopenaeus kroyeri and Rimapenaeus constrictus), indicating that some these loci can be useful in studies of other related species. 相似文献
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LUIS PALAZZESI MARC GOTTSCHLING VIVIANA BARREDA MAXIMILIAN WEIGEND 《Biological journal of the Linnean Society. Linnean Society of London》2012,107(1):67-85
The origin of Geraniales (approximately 900 species in three families: Geraniaceae, Melianthaceae, and Vivianiaceae) is traced back to the Cretaceous of Gondwana, yet their geotemporal history is largely unknown because of a limited fossil record and incomplete phylogenies. In the present study, we provide the first fossil record of Vivianiaceae and a highly resolved molecular phylogeny for all extant Geraniales genera. Our results support the hypothesis that five (instead of three) families should be recognized in the order Geraniales: Francoaceae A. Juss. (Francoa, Greyia, Tetilla), Geraniaceae Juss. (Erodium, Geranium, Monsonia, Pelargonium), Hypseocharitaceae Wedd. (monogeneric), Melianthaceae Horan. (Bersama, Melianthus), and Vivianiaceae Klotzsch (Balbisia, Rhynchotheca, Viviania). The four major lineages (i.e. Geraniaceae, Francoaceae + Melianthaceae, Hypseocharitaceae, Vivianiaceae) all originated within a narrow time frame during the Eocene (36.9–49.9 Mya) based on the five fossil calibration points. The divergence of most of the extant genera occurred much later, from the Miocene onwards. The South American–South African disjunction in Francoaceae apparently goes back to long distance dispersal with an estimated divergence time of the lineages in the Middle Miocene [11.2 (5.9–17.7) Mya]. Diversification in Melianthus appears to be much more recent than previously assumed [starting approximately 3.4 (1.9–5.2) Mya rather than approximately 8–20 Mya]. However, divergence of the Andean Hypseocharis lineage [36.9 (31.9–42.8) Mya] significantly predates the main Andean uplift: Current distributions likely go back to northward migrations and subsequent extinctions in Patagonia. Similarly, Rhynchotheca, Balbisia, and Viviania have a current southern distribution limit > 10°N of the fossil finds, indicating a massive northward displacement. The present evidence suggests that niche conservatism likely played a major role in the historical biogeography of Geraniales. © 2012 The Linnean Society of London, Biological Journal of the Linnean Society, 2012, ?? , ??–??. 相似文献
87.
SANTIAGO MERINO RODRIGO A. VÁSQUEZ JAVIER MARTÍNEZ JUAN LUIS CELIS-DIEZ LETICIA GUTIÉRREZ-JIMÉNEZ SILVINA IPPI INOCENCIA SÁNCHEZ-MONSALVEZ JOSUÉ MARTÍNEZ-DE LA PUENTE 《Biological journal of the Linnean Society. Linnean Society of London》2009,98(3):568-576
The Microbiotheriid Dromiciops gliroides , also known as 'Monito del Monte', is considered to be a threatened species and the only living representative of this group of South American marsupials. During the last few years, several blood samples from specimens of 'Monito del Monte' captured at Chiloé island in Chile have been investigated for blood parasites. Inspection of blood smears detected a Hepatozoon species infecting red blood cells. The sequences of DNA fragments corresponding to small subunit ribosomal RNA gene revealed two parasitic lineages belonging to Hepatozoon genus. These parasite lineages showed a basal position with respect to Hepatozoon species infecting rodents, reptiles, and amphibians but are phylogenetically distinct from Hepatozoon species infecting the order Carnivora. In addition, the Hepatozoon lineages infecting D. gliroides are also different from those infecting other micro-mammals living in sympatry, as well as from some that have been described to infect an Australian species of bandicoot. The potential vector of this parasite appears to be the host-specific tick Ixodes neuquenensis because the sequencing of a long amplicon determined the presence of one of the two lineages found in the marsupial. © 2009 The Linnean Society of London, Biological Journal of the Linnean Society , 2009, 98 , 568–576. 相似文献
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IVÁN DE LA HERA JAVIER PÉREZ-TRIS JOSÉ LUIS TELLERÍA 《Biological journal of the Linnean Society. Linnean Society of London》2009,97(1):98-105
Migratory birds have less time for moulting than sedentary birds, which may force them to produce their feathers faster at the expense of reducing feather quality. However, the effects of migration on the trade-off between moult speed and plumage quality remain to be studied in natural populations. We analysed the relationship between growth rate and quality of individual feathers, taking advantage of natural variation between migratory and sedentary populations of blackcaps Sylvia atricapilla . As predicted by life-history theory, individual blackcaps showed variable individual quality, which was revealed by positive correlations between feather growth rate and feather mass within populations. However, migrants grew up their feathers faster, producing lighter feathers than sedentary blackcaps. These results support the idea that feather growth rate and feather quality are traded against each other in blackcaps. Such a trade-off is apparently caused by different selection associated to migratory and sedentary life styles, which opens new insights into the diversification of moult patterns in birds. © 2009 The Linnean Society of London, Biological Journal of the Linnean Society , 2009, 97 , 98–105. 相似文献
90.
1. Food webs represent the paths of material and energy flow through organisms in an ecosystem. Anuran larvae are important components of pond food webs: they are abundant, consume large quantities of food and serve as prey for many organisms. However, there are very basic uncertainties about the feeding ecology of anuran larvae; for instance, as to which trophic level they belong and whether species differ in resource use. Because anuran larvae have been employed in model systems in experimental ecology for decades, these uncertainties could lead to misinterpretation of published experiments, or inadequate designs of experiments directed at general, conceptual issues in ecology.
2. Using13 C and 15 N stable isotope and gut content analyses of free-ranging and enclosed tadpoles of four ranid species ( Lithobates sylvaticus , L. pipiens , L. clamitans , L. catesbeianus ) in the food webs of six wetlands, we tested the following null hypotheses: (i) that anuran larvae are strict primary consumers; (ii) that they are non-selective feeders and therefore exhibit little feeding niche differentiation; (iii) that they are opportunistic consumers and (iv) that their diet remains unchanged through ontogeny.
3. All four species consumed and assimilated substantial amounts of animal food; bullfrog larvae, in particular, appear to be predatory. Significant feeding niche differentiation among species occurred with respect to the sources of carbon, consumption of animal matter and nutritional quality of food ingested. We further documented opportunistic feeding habits and ontogenetic shifts in diet.
4. Collectively, these studies revealed complex trophic relationships that might require a reconsideration of the role of anuran larvae in pond food webs, as well as a reinterpretation of results of previous studies employing anuran larvae in model experimental systems. 相似文献
2. Using
3. All four species consumed and assimilated substantial amounts of animal food; bullfrog larvae, in particular, appear to be predatory. Significant feeding niche differentiation among species occurred with respect to the sources of carbon, consumption of animal matter and nutritional quality of food ingested. We further documented opportunistic feeding habits and ontogenetic shifts in diet.
4. Collectively, these studies revealed complex trophic relationships that might require a reconsideration of the role of anuran larvae in pond food webs, as well as a reinterpretation of results of previous studies employing anuran larvae in model experimental systems. 相似文献