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991.
JUAN ARMANDO SÁNCHEZ 《Zoological Journal of the Linnean Society》2009,157(2):237-263
Candelabrum gorgonian corals (genus Eunicea Lamouroux, 1816 ), with 15 valid species, comprise the most diverse and abundant group of octocorals in Caribbean coral reefs. The systematics of Eunicea was estimated based on 17 discrete morphological characters, mostly from sclerite morphology. Club sclerites, found on the surface of gorgonian tissue, provided the largest number of informative characters. A maximum parsimony analysis corroborated the monophyletic status of the group and the two internal groups (subgenera Eunicea s.s. and Euniceopsis Verrill). Differentiation based on the distribution and architecture of modules (e.g. polyps and calyces), as well as colony size and fecundity in females, was consistent amongst sister species (e.g. the new species and their closest morphological sister species) but not within species [e.g. amongst Eunicea succinea (Pallas) morphotypes], suggesting species boundaries for this group. Candelabrum gorgonian corals seem to be distributed indistinctively throughout the Caribbean province, where habitat requirements are met. One new species widely distributed in the Caribbean was described ( Eunicea tayrona sp. nov. ) using electron microscopy. Eunicea tayrona is externally similar to Eunicea fusca but there are numerous morphological and ecological differences between them. The morphotypes and phenotypic plasticity from Eunicea clavigera Bayer, Eunicea calyculata (Ellis & Solander), and Eunicea tourneforti Milne Edwards & Haime still deserve further study and might clarify the presence of additional new Eunicea species. 相似文献
992.
A.M Jordan 《Trends in parasitology》2001,17(11):553-554
993.
ROBERT J. SWAP THOMAS A. SZUBA MICHAEL GARSTANG HAROLD J. ANNEGARN† LACKSON MARUFU‡ STUART J. PIKETH§ 《Global Change Biology》2003,9(3):336-345
The primary source of the annual austral spring mid‐tropospheric ozone maxima over the tropical South Atlantic has generally been assumed to be biomass burning. However, ozone precursor emissions from biogenic, lightning, and anthropogenic sources in subequatorial Africa before and during the ozone peak are shown to be comparable, if not greater, in magnitude to regional biomass burning production. Moreover, an investigation of the spatial and temporal characteristics of these ozone precursor sources (i.e. vegetative and microbial activity, lightning‐induced generation, and anthropogenic emissions) suggests that these alternative sources can potentially make a substantial contribution to the seasonal ozone peak. This argument is supported by the practical limitations of atmospheric transport available to regionally produced ozone and ozone precursors. 相似文献
994.
995.
Amy R. Bentley Jasmin Divers Daniel Shriner Ayo P. Doumatey Orlando M. Gutiérrez Adebowale A. Adeyemo Barry I. Freedman Charles N. Rotimi 《BMC genomics》2015,16(1)
Background
Despite evidence of an association between variants at the apolipoprotein L1 gene (APOL1) locus and a spectrum of related kidney diseases, underlying biological mechanisms remain unknown. An earlier preliminary study published by our group showed that an APOL1 variant (rs73885319) modified the association between high-density lipoprotein cholesterol (HDLC) and estimated glomerular filtration rate (eGFR) in African Americans. To further understand this relationship, we evaluated the interaction in two additional large cohorts of African Americans for a total of 3,592 unrelated individuals from the Howard University Family Study (HUFS), the Natural History of APOL1-Associated Nephropathy Study (NHAAN), and the Atherosclerosis Risk in Communities Study (ARIC). The association between HDLC and eGFR was determined using linear mixed models, and the interaction between rs73885319 genotype and HDLC was evaluated using a multiplicative term.Results
Among individuals homozygous for the risk genotype, a strong inverse HDLC-eGFR association was observed, with a positive association in others (p for the interaction of the rs73885319 × HDLC =0.0001). The interaction was similar in HUFS and NHAAN, and attenuated in ARIC. Given that ARIC participants were older, we investigated an age effect; age was a significant modifier of the observed interaction. When older individuals were excluded, the interaction in ARIC was similar to that in the other studies.Conclusions
Based on these findings, it is clear that the relationship between HDLC and eGFR is strongly influenced by the APOL1 rs73885319 kidney risk genotype. Moreover, the degree to which this variant modifies the association may depend on the age of the individual. More detailed physiological studies are warranted to understand how rs73885319 may affect the relationship between HDLC and eGFR in individuals with and without disease and across the lifespan.Electronic supplementary material
The online version of this article (doi:10.1186/s12864-015-1645-7) contains supplementary material, which is available to authorized users. 相似文献996.
997.
998.
Chen Chen Deping Hua Jingxuan Shi Zheng Tan Min Zhu Kun Tan Lilin Zhang Jinhai Huang 《中国病毒学》2021,36(2):207-219
African swine fever virus(ASFV) infects domestic pigs and European wild boars with strong, hemorrhagic and high mortality. The primary cellular targets of ASFV is the porcine macrophages. Up to now, no commercial vaccine or effective treatment available to control the disease. In this study, three recombinant Saccharomyces cerevisiae(S. cerevisiae) strains expressing fused ASFV proteins-porcine Ig heavy chains were constructed and the immunogenicity of the S. cerevisiae-vectored cocktail ASFV feeding vaccine was further evaluated. To be specific, the P30-Fcc and P54-Fca fusion proteins displaying on surface of S. cerevisiae cells were produced by fusing the Fc fragment of porcine immunoglobulin Ig G1 or IgA1 with p30 or p54 gene of ASFV respectively. The recombinant P30-Fcc and P54-Fca fusion proteins expressed by S. cerevisiae were verified by Western blotting, flow cytometry and immunofluorescence assay.Porcine immunoglobulin Fc fragment fused P30/P54 proteins elicited P30/P54-specific antibody production and induced higher mucosal immunity in swine. The absorption and phagocytosis of recombinant S. cerevisiae strains in IPEC-J2 cells or porcine alveolar macrophage(PAM) cells were significantly enhanced, too. Here, we introduce a kind of cheap and safe oral S. cerevisiae-vectored vaccine, which could activate the specific mucosal immunity for controlling ASFV infection. 相似文献
999.
Lina Vanesa Garzón-Peña Angelica Barrera-García Antonio Delgado-Huertas Carlos Julio Polo-Silva 《Journal of fish biology》2021,98(5):1456-1458
Isotopic values of two Caribbean sharpnose shark Rhizoprionodon porosus litters (Poey, 1861) with two and three embryos and one litter of 11 smalltail shark Carcharhinus porosus embryos showed enriched 15N and 13C compared to their mothers. In R. porosus, embryonic isotope values were 3.06 ± 0.07‰ and 0.69 ± 0.15‰ greater than their mothers' for δ15N and δ13C, respectively, whereas in C. porosus, δ15N and δ13C were 1.79 ± 0.09‰ and 1.31 ± 0.17‰ greater in embryos than their mothers. 相似文献
1000.
Adam P. Van Arsdale Milford H. Wolpoff 《Evolution; international journal of organic evolution》2013,67(3):841-850
The relationship between Homo habilis and early African Homo erectus has been contentious because H. habilis was hypothesized to be an evolutionary stage between Australopithecus and H. erectus, more than a half‐century ago. Recent work re‐dating key African early Homo localities and the discovery of new fossils in East Africa and Georgia provide the opportunity for a productive re‐evaluation of this topic. Here, we test the hypothesis that the cranial sample from East Africa and Georgia represents a single evolutionary lineage of Homo spanning the approximately 1.9–1.5 Mya time period, consisting of specimens attributed to H. habilis and H. erectus. To address issues of small sample sizes in each time period, and uneven representation of cranial data, we developed a novel nonparametric randomization technique based on the variance in an index of pairwise difference from a broad set of fossil comparisons. We fail to reject the hypothesis of a single lineage this period by identifying a strong, time‐dependent pattern of variation throughout the sequence. These results suggest the need for a reappraisal of fossil evidence from other regions within this time period and highlight the critical nature of the Plio‐Pleistocene boundary for understanding the early evolution of the genus Homo. 相似文献