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901.
《Journal of Natural History》2012,46(1-2):129-137
Plants bearing extrafloral nectaries can attract wasps, bugs, and mainly ants. Ants can defend plants against herbivores by treating the plant as an extension of their own territory. We evaluated the efficiency of resting sites built by Dryas iulia alcionea larvae as protection against ant predation on their host plant Passiflora suberosa. The results showed that ants on P. suberosa have significant influence on the survival of D. iulia caterpillars. The use and construction of resting sites was recorded through the fourth larval stadium. A strong inverse relationship between the number of resting sites constructed per larva and the developmental stage of the larvae was observed. Additional results suggest that the efficacy of resting sites against cursorial predators decreases with larval development. The behaviour of constructing resting sites probably evolved by natural selection. It is likely that this behaviour was important for the ancestral lineage that gave origin to Heliconiinae genera Dryas, Dryadula and Phylaethria. 相似文献
902.
《Journal of Natural History》2012,46(21-22):1549-1563
That the ties between any obligate subterranean species and the hypogean environment depend on the interplay of a species' own physiological characteristics and all of the ecological characteristics of the adjacent epigean habitat(s), including biotic factors, has been emphasized. The reasons why troglomorphy cannot be included within criteria for classifying cave dwellers have been demonstrated. After a review of historic classifications, standardized definitions of the most widely used terms are proposed. The most easily recognized are four categories which are terminological approximations of the classic Schiner‐Racovitza terminology: (1) troglobiont is a species or population, strictly bound to a hypogean habitat; (2) eutroglophile is an essentially epigean species, but able to maintain a permanent subterranean population; (3) subtroglophile is inclined perpetually or temporarily to inhabit a subterranean habitat but is bound to the surface for some biological functions (e.g. feeding); (4) trogloxene is a species only occurring sporadically underground. 相似文献
903.
904.
《Journal of Natural History》2012,46(8):597-606
The Gordiida species Chordodes moraisi (Carvalho, ) and C. staviarskii Carvalho and Feio, are re‐described using scanning electron microscopy (SEM). Chordodes moraisi is characterized by four areole types, two of which correspond to tubercle areoles, the crown areoles appear as single structures and occur on both sides along the ventral midline. Chordodes staviarskii is characterized by a polymorphism of crowned areoles which appear as two types with distinct distribution patterns. Two species, Chordodes gestri Camerano, and Pseudochordodes griffinii (Camerano, ), are synonymized with Neochordodes occidentalis (Montgomery, 1898) and Chordodes peraccae (Camerano, 1894). 相似文献
905.
《Journal of Natural History》2012,46(7):539-554
Bryozoans are one of the major macrofaunal groups of the high polar regions. Here we present data on the nature of bryozoan assemblages in the Svalbard Archipelago sampled over 6 years between 1997 and 2002. Samples were collected with use of Van Veen grab, dredge and Scuba diving at depths ranging from 0 to 268?m. Among examined material (5026 items) bryozoans were present on one type of abiotic (stones) and 40 types of biotic substrata. The biotic substrata we investigated included algae (12 taxa) and invertebrates (28 taxa: Hydrozoa, Gastropoda, Bivalvia, Polychaeta, Crustacea, Ascidiacea, other Bryozoa). Both a priori ANOSIM (Global R?=?0.512, P?=?0.001) and cluster analyses reveal differences between the assemblages on different types of substrata. Cluster analyses distinguish two distinct groups of substrata. The first (stable) included stones, molluscs and Balanus balanus whilst the second (flexible) consisted of algae, hydrozoans and bryozoans. Bryozoan assemblages which colonized different substrata, varied in terms of species composition and their dominance. Bryozoan species were categorized as generalists, low‐specificity epibiotic species or locally abundant background species. No species were found to be substratum‐specific to any type. Among substrata with the richest bryozoan fauna were stones (156 taxa), Chlamys islandica (68) and Balanus balanus (62). There were clear patterns in the distribution of substrata colonized by bryozoans within the fjord system: those shallow near the mouth were rich whilst those in deeper water were depauperate. We consider environmental gradients such as siltation and processes related to depth to be responsible for such patterns. 相似文献
906.
《Journal of Natural History》2012,46(27):2483-2514
A faunistic survey of the deep‐sea hyperbenthic copepods in the Sulu Sea, which has a deep basin and is connected via shallow straits with the Pacific and the South China Sea, was carried out in November and December 2002, using beam trawls and a mid‐water trawl. Two new genera and four new species of the primitive calanoid family Arietellidae are described. A new genus Metacalanalis shows intermediate characteristics between those of Metacalanus Cleve, 1901 and Pilarella Alvarez, . Another new genus, Protoparamisophria, is closely related to Paramisophria Scott, 1897, but exhibits more plesiomorphic states in the female genital system and appendages. Two new species of the genera Paraugaptiloides Ohtsuka, Boxshall and Roe, and Sarsarietellus Campaner, 1984 are the second and the third species, respectively, for these genera. This discovery enhances the validity of these rare genera, and sheds light on the geological history of the Sulu Sea and the evolution of the Arietellidae within it. 相似文献
907.
《Journal of Natural History》2012,46(26):2409-2479
The majority of the 58 species discussed, including 10 new species, were collected by scuba divers at 5–10?m in waters around Australia. Species are from Leptoclinides (11), Polysyncraton (11), Didemnum (19), Trididemnum (7), Lissoclinum (8), Clitella (1), and Diplosoma (1), and new species are in all except Trididemnum and Diplosoma. Additional characters (including a pyloric vesicle reported previously in the Holozoidae and several unrelated didemnid taxa) have been detected for the monotypic genus Clitella Kott, , which is recorded for only the second time. A review of known Australian ascidian species confirms the Didemnidae as the most speciose ascidian family in these waters. In this family, there appears not to be appreciable gene flow between tropical and temperate waters and few species have a continuous tropical–temperate range. A preponderance of Western Pacific non‐indigenous species is in the north, while indigenous species, some probably isolated from related tropical ones, are dominant in the temperate waters of the southern half of the continent. Although intraspecific variation and convergence obscures species differences, some aspects of the living organisms detected in in situ photographs contribute to identification. Keys to Australian didemnid species described since the publication of the Australian Ascidiacea part 4, Didemnidae (Kott ) are included. 相似文献
908.
《Journal of Natural History》2012,46(13-16):925-936
Morphological and genetic data for the Iberian golden‐striped salamander, Chioglossa lusitanica, demonstrate the existence of two groups with southern and northern ranges, connected by a zone of intergradation in central Portugal. Because reproductive isolation between them is incomplete we consider the groups to be subspecies. The type locality of C. lusitanica (Buçaco near Lousã) is situated inside the mixed zone. This necessitates identification of the nominotypical subspecies. We sequenced a fragment of mitochondrial DNA from one of the species' syntypes and we determined what position over a latitudinal transect maximizes the morphological discrimination between the groups. Both approaches indicate that C. lusitanica from Buçaco represents the southern subspecies. A new subspecies of C. lusitanica is described from a northern locality (Valongo near Porto in north‐western Portugal). A lectotype is designated for Chioglossa lusitanica. 相似文献
909.
《Journal of Natural History》2012,46(39-40):2585-2591
In the present study, the cloning and sequence analysis of interleukin‐6 (IL‐6) from the giant panda (Ailuropoda melanoleuca) were described. Sequencing revealed that IL‐6 complementary DNA contains a 636 base‐pair open reading frame encoding 211 amino acids. Homology analyses indicated that the identity levels of nucleotide and deduced amino acid sequences of IL‐6 between the giant panda and other species in Carnivora ranged from 90.5% to 85.6% and from 82.9% to 76.5%, respectively. Phylogenetic analyses based on nucleotide and amino acid sequences showed that the harbour seal shared a closer relationship with the giant panda than other carnivores (ursids not included). The functionally important domains and sites that have previously been recognized in other carnivores were all observed in the IL‐6 sequence of the giant panda. These findings suggest that the complementary DNA fragment cloned is indeed the IL‐6 molecule with biological activity and can be used in immunological studies of the giant panda. 相似文献
910.
Observing that a sequence of negative logarithms of 1‐year survival probabilities displays a linear relationship with the sequence of corresponding terms with a time lag of a certain number of years, we propose a simple linear regression to model and forecast mortality rates. Our model assuming the linearity between two mortality sequences with a time lag each other does not need to formulate the time trends of mortality rates across ages for mortality prediction. Moreover, the parameters of our model for a given age depend on the mortality rates for that age only. Therefore, whether the span of the study ages with the age included is widened or shortened will not affect the results of mortality fitting and forecasting for that age. In the empirical testing, the regression results using the mortality data for the UK, USA and Japan show a satisfactory goodness of fit, which convinces us of the appropriateness of the linear assumption. Empirical illustrations further show that our model's performances of fitting and forecasting mortality rates are quite satisfactory compared with the existing well‐known mortality models. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献