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991.
A new species of deepwater cardinal fish,Epigonus merleni, is described from a specimen found floating at the sea surface as a result of the eruption of Fernandina Volcano, Isla Fernandina,
Galápagos Islands. It differs from all knownEpigonus in having the greatest number of lateral line scales (57) and the fewest gill rakers (17), as well as in several other characters. 相似文献
992.
Living lingulid brachiopods are ubiquitous in low-latitude, marine infaunas. Lingula occurs throughout the Pacific and Indian oceans with the only Atlantic species, L. parva, confined to West Africa. Glottidia is restricted to offshore America from Virginia to California and Peru, and is assumed to have descended from a Pacific Lingula during the early Tertiary. Lingulid organophosphatic shells differ structurally. That of Glottidia is characterizedby trellised rods (baculate); that of Indo-Pacific species of Lingula by spheroidal and rod-like microstructures (virgose); and that of L. parva by apatitic rods arranged as spherulites. A spherulitic fabric is unknown in fossil lingulids, but the distinction between GlottidiaLingula can be traced back to the Carboniferous, which accords with the deep molecular divergence between the two genera. The common occurrence of lingulids with baculate shells in European post-Palaeozoic sediments suggests that ancestral Glottidia entered the Atlantic by the Tethyan Current during the Late Cretaceous/early Cenozoic, and migrated into the Pacific before the formation of the Panama Isthmus. Penecontemporaneously, antecedents of L. parva possibly migrated from east Tethys along the trans-Saharan seaway. 相似文献
993.
Hai Wu Dan Li Yuxi Shan Bo Wan Saiyin Hexige Jinhu Guo Chaoqun Wu Long Yu 《DNA sequence》2007,18(1):73-79
Human EFCBP/NECAB family consists of important participants in neuronal calcium signaling, including EFCBP1/NECAB1, EFCBP2/NECAB2 and EFCBP3/NECAB3. In the present study, we identified the full-length 5229 bp EFCBP1 cDNA which was not described before. Human EFCBP1 encodes a 351 amino acid protein containing two EF-hand motifs and an antibiotic biosynthesis monooxygenase (ABM) domain, sharing 49.9 and 56.8% global homology with human EFCBP2 and EFCBP3. Northern hybridization revealed that EFCBP1 is specifically expressed in brain and its abundance varies in different brain regions. EFCBP1's abundance in temporal lobe, frontal lobe and occipital pole is about 3.4, 1.9 and 1.5 folds of the average abundance in cerebral cortex, respectively. The expression level of EFCBP1 equals in putamen and cerebral cortex, while no hybridization signal was detected in spinal cord. In addition, we found that EFCBP1, EFCBP2 and EFCBP3 share a similar exon distribution mode, though their chromosomal localizations, genomic sizes and intron sizes are diverse. 相似文献
994.
Toxicity in leaves of rice exposed to cadmium is due to hydrogen peroxide accumulation 总被引:4,自引:0,他引:4
The production of H2O2 in detached rice leaves of Taichung Native 1 (TN1) caused by CdCl2 was investigated. CdCl2 treatment resulted in H2O2 production in detached rice leaves. Diphenyleneiodonium chloride (DPI) and imidazole (IMD), inhibitors of NADPH oxidase (NOX),
prevented CdCl2-induced H2O2 production, suggesting that NOX is a H2O2-genearating enzyme in CdCl2-treated detached rice leaves. Phosphatidylinositol 3-kinase inhibitors wortmanin (WM) or LY294002 (LY) inhibited CdCl2-inducted H2O2 production in detached rice leaves. Exogenous H2O2 reversed the inhibitory effect of WM or LY, suggesting that phosphatidylinositol 3-phosphate is required for Cd-induced H2O2 production in detached rice leaves. Nitric oxide donor sodium nitroprusside (SNP) was also effective in reducing CdCl2-inducing accumulation of H2O2 in detached rice leaves. Cd toxicity was judged by the decrease in chlorophyll content. The results indicated that DPI, IMD,
WM, LY, and SNP were able to reduce Cd-induced toxicity of detached rice leaves. Twelve-day-old TN1 and Tainung 67 (TNG67)
rice seedlings were treated with or without CdCl2. In terms of Cd toxicity (leaf chlorosis), it was observed that rice seedlings of cultivar TN1 are Cd-sensitive and those
of cultivar TNG67 are Cd-tolerant. On treatment with CdCl2, H2O2 accumulated in the leaves of TN1 seedlings but not in the leaves of TNG67. Prior exposure of TN1 seedlings to 45oC for 3 h resulted in a reduction of H2O2 accumulation, as well as Cd tolerance of TN1 seedlings treated with CdCl2. The results strongly suggest that Cd toxicity of detached leaves and leaves attached to rice seedlings are due to H2O2 accumulation. 相似文献
995.
R. J. Delahay A. I. Ward N. Walker B. Long & C. L. Cheeseman 《Journal of Zoology》2007,272(3):311-320
Eurasian badgers Meles meles habitually deposit droppings and other scent marks at latrines, which may be associated with territorial defence, and communicate information related to group and individual identity and status, and food resources. Understanding patterns of latrine distribution contributes to our understanding of badger social behaviour, and may be relevant to managing the risks of transmission of bovine tuberculosis from badgers to cattle. We investigated the distribution of badger latrines relative to habitat composition in a high-density badger population occupying a 7 km2 area of diverse landscape in south-west England. Results indicated that the frequency and density of badger latrines varied according to land use, with woodland and linear landscape features (particularly hedges and stone walls) being positively selected. The number of latrines decreased significantly with distance from linear features. Grassland was negatively selected given its availability, but contained the highest number of latrines. The tendency for latrines to be associated with particular habitat types covaried spatially across the study area. We present a habitat selection probability function, based on the output of our analyses, to allow comparison of observed versus expected latrine counts per habitat type at different sites. Habitat manipulation on farmland may offer opportunities to manage exposure of cattle to badger latrines. However, our analyses indicate that other factors (perhaps demographic or environmental) may also exert a substantial local influence on latrine location. 相似文献
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