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971.
972.
Sandy ocean beaches are iconic assets that provide irreplaceable ecosystem services to society. Despite their great socioeconomic importance, beaches as ecosystems are severely under‐represented in the literature on climate‐change ecology. Here, we redress this imbalance by examining whether beach biota have been observed to respond to recent climate change in ways that are consistent with expectations under climate change. We base our assessments on evidence coming from case studies on beach invertebrates in South America and on sea turtles globally. Surprisingly, we find that observational evidence for climate‐change responses in beach biota is more convincing for invertebrates than for highly charismatic turtles. This asymmetry is paradoxical given the better theoretical understanding of the mechanisms by which turtles are likely to respond to changes in climate. Regardless of this disparity, knowledge of the unique attributes of beach systems can complement our detection of climate‐change impacts on sandy‐shore invertebrates to add rigor to studies of climate‐change ecology for sandy beaches. To this end, we combine theory from beach ecology and climate‐change ecology to put forward a suite of predictive hypotheses regarding climate impacts on beaches and to suggest ways that these can be tested. Addressing these hypotheses could significantly advance both beach and climate‐change ecology, thereby progressing understanding of how future climate change will impact coastal ecosystems more generally. 相似文献
973.
Santosh Kumar Daizy Bharti Silvia Marinsalti Emilio Insom Antonietta La Terza 《The Journal of eukaryotic microbiology》2014,61(3):247-259
A terrestrial oxytrichid ciliate Paraparentocirrus sibillinensis n. gen., n. sp., which was found in soil samples of a beech forest stand within the National Park of Sibillini Mountains, Italy, was investigated using live observation and protargol impregnation. The morphology of interphase, morphogenesis, and molecular phylogeny inferred from SSU rDNA sequences of this ciliate were studied. Paraparentocirrus n. gen., is mainly characterized by a semirigid body, an undulating membrane in the Oxytricha pattern, six fronto‐ventral (FV) rows, the absence of transverse cirri, one right and one left row of marginal cirri, four dorsal kineties, two dorsomarginal rows, and caudal cirri at the end of dorsal kinety 4. During morphogenesis, oral primordia develop through the proliferation of basal bodies from some cirri of FV rows 4 and 5, and FV row 6 takes part in the anlagen formation of the proter. The dorsal morphogenesis was typical of oxytrichids, with simple fragmentation of dorsal kinety 3, and the dorsomarginal rows developed from the right marginal row. Phylogenetic analyses based on the SSU rDNA sequences support the classification of this new genus in the stylonychines. 相似文献
974.
Two new species, Eotrichocera (Archaeotrichocera) longensis
sp. n. and Eotrichocera (Archaeotrichocera) amabilis
sp. n. of Trichoceridae are described based on a combination of the following characters: Sc ending proximad of the forking of R2, shape of d cell and A2 rather short and bending sharply toward posterior margin. These fossil specimens were collected from the Middle Jurassic Jiulongshan Formation of Daohugou in Inner Mongolia, China. 相似文献
975.
Andrew L. Stewart Theodore W. Pietsch Jon Moore Xiaotong Peng 《Journal of fish biology》2024,104(3):887-891
This note reports on eight observations of inverted swimming behavior by species of ceratioid whipnose anglerfishes in the genus Gigantactis, from the Caribbean, tropical east Atlantic, tropical western Indian Ocean, the north-east and north-west Pacific and south-west Pacific. It covers four putative species and strongly suggests that this is the normal behavior for the genus. A possible reason is briefly discussed. In addition, a new depth record of 5866 m for the ceratioid anglerfish is recorded. 相似文献
976.
Tettigarctidae (Insecta: Hemiptera: Cicadoidea) from the Middle Jurassic of Inner Mongolia, China 总被引:1,自引:0,他引:1
Three new species of Tettigarctidae from the Middle Jurassic of Daohugou, China are described: Shuraboprosbole daohugouensis nov. sp., S. minuta nov. sp., and S. media nov. sp. The revised diagnostic characters of Shuraboprosbole Becker-Migdisova are provided based on well-preserved whole-bodied fossil tettigarctids. So far, only four definitive species of Tettigarctidae are recorded from the Mesozoic of China. The pronotum concealing major of mesonotum seems to be an autapomorphy of Tettigarctinae. The “cicadellid-like tarsi” found in Cicadellidae and Brazilian Tettigarctidae are probably a parallel evolution. 相似文献
977.
978.
Testing the enemy release hypothesis: a review and meta-analysis 总被引:1,自引:0,他引:1
One of the most cited hypotheses explaining the inordinate success of a small proportion of introduced plants that become
pests is the ‘natural enemies hypothesis’. This states that invasive introduced plants spread rapidly because they are liberated
from their co-evolved natural enemies. This hypothesis had not been properly tested until recently. Previous reviews on this
topic have been narrative and vote counting in nature. In this review, we carried out quantitative synthesis and meta-analysis
using existing literature on plants and their herbivores to test the different components of the enemy release hypothesis.
We found supporting evidence in that (1) insect herbivore fauna richness is significantly greater in the native than introduced
ranges, and the reduction is skewed disproportionally towards specialists and insects feeding on reproductive parts; and (2)
herbivore damage levels are greater on native plants than on introduced invasive congeners. However, herbivore damage levels
are only marginally greater for plants in native than in introduced ranges, probably due to the small numbers of this type
of study. Studies quantifying herbivore impacts on plant population dynamics are too scarce to make conclusions for either
comparison of plants in native vs introduced ranges or of co-occurring native and introduced congeners. For future research,
we advocate that more than two-way comparisons between plants in native and introduced ranges, or native and introduced congeners
are needed. In addition, the use of herbivore exclusions to quantify the impacts of herbivory on complete sets of population
vital rates of native vs introduced species are highly desirable. Furthermore, three-way comparisons among congeners of native
plants, introduced invasive, and introduced non-invasive plants can also shed light on the importance of enemy release. Finally,
simultaneously testing the enemy release hypothesis and other competing hypotheses will provide significant insights into
the mechanisms governing the undesirable success of invasive species. 相似文献
979.
A. I. Camacho T. Torres C. J. Puch J. E. Ortiz Antonio G. Valdecasas 《Biodiversity and Conservation》2006,15(11):3527-3541
An analysis was made of the micro-distribution patterns of five phylogenetically closely related species belonging to the
genus Iberobathynella, a group of subterranean aquatic crustaceans (Syncarida, Parabathynellidae). The two-step model of colonization and speciation
seems to provide a valid explanation for the current distribution of a large number of stygobiontic taxa of marine origin
(thalassoid). However, with respect to the Iberobathynella, only the colonization of the subterranean environment at the mesoscale level can be explained. The second phase of the model,
marine regression, can only explain the colonization of the region by the ancestor; the subsequent evolution and speciation
at a smaller scale remain to be explained. Local geological constraints – Upper Triassic gypsiferous mudstone deposits plus
faults and thrusting linked to the Alpine Orogeny – are responsible for the appearance of local palaeogeographic phenomena.
These may have been the vicariant processes responsible for the geographical and genetic isolation of the ancestral populations
of this group, which eventually led to clade divergence. Together with small-scale passive dispersion (11 dispersal events)
and local extinction, these processes could be responsible for the current distribution of the five sister taxa inhabiting
the caves of the Sierra de la Collada, Spain. A plausible palaeogeographical scenario is offered to explain their present
distribution, that clearly came about through chance events. 相似文献
980.
The site of Mansourah (Constantine, Algeria) had yielded to the early authors, and more recently to the late G. Laplace, a lithic industry associated with a fauna of large Mammals, which looks contemporaneous with that of Aïn Hanech, although it is well-distinct ecologically, and might even be slightly older. The lithic assemblage is completely devoid of any bifacial artefact or cleaver and can only be referred to the Oldowan. Thus, the Mansourah site documents a very early human occupation of North Africa, and perhaps one of the earliest. To cite this article: Y. Chaid-Saoudi et al., C. R. Palevol 5 (2006). 相似文献