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91.
S. Fox I. Foisy R. De La Parra Venegas B. E. Galván Pastoriza R. T. Graham E. R. Hoffmayer J. Holmberg S. J. Pierce 《Journal of fish biology》2013,83(3):574-587
There were 479 reported whale shark Rhincodon typus encounters between 1999 and 2011 at the island of Utila, which forms part of the Meso‐American Barrier Reef System (MBRS) in the western Caribbean Sea. The majority of R. typus were found to feed on small bait fish associated with various tuna species. Ninety‐five individual R. typus, ranging from 2 to 11 m total length (LT), were identified through their unique spot patterns. A significant male bias (65%) was present. There was no significant difference between the mean ± s.d . LT of female (6·66 ± 1·65 m) and male (6·25 ± 1·60 m) R. typus. Most R. typus were transient to Utila, with 78% sighted only within a single calendar year, although some individuals were sighted in up to 5 years. Mean residency time was modelled to be 11·76 days using maximum likelihood methods. 相似文献
92.
Glen E. Mellor Thomas E. Besser Margaret A. Davis Brittany Beavis WooKyung Jung Helen V. Smith Amy V. Jennison Christine J. Doyle P. Scott Chandry Kari S. Gobius Narelle Fegan 《Applied and environmental microbiology》2013,79(16):5050-5058
Escherichia coli O157 is a food-borne pathogen whose major reservoir has been identified as cattle. Recent genetic information has indicated that populations of E. coli O157 from cattle and humans can differ genetically and that this variation may have an impact on their ability to cause severe human disease. In addition, there is emerging evidence that E. coli O157 strains from different geographical regions may also be genetically divergent. To investigate the extent of this variation, we used Shiga toxin bacteriophage insertion sites (SBI), lineage-specific polymorphisms (LSPA-6), multilocus variable-number tandem-repeat analysis (MLVA), and a tir 255T>A polymorphism to examine 606 isolates representing both Australian and U.S. cattle and human populations. Both uni- and multivariate analyses of these data show a strong association between the country of origin and multilocus genotypes (P < 0.0001). In addition, our results identify factors that may play a role in virulence that also differed in isolates from each country, including the carriage of stx1 in the argW locus uniquely observed in Australian isolates and the much higher frequency of stx2-positive (also referred to as stx2a) strains in the U.S. isolates (4% of Australian isolates versus 72% of U.S. isolates). LSPA-6 lineages differed between the two continents, with the majority of Australian isolates belonging to lineage I/II (LI/II) (LI, 2%; LI/II, 85%; LII, 13%) and the majority of U.S. isolates belonging to LI (LI, 60%; LI/II, 16%; LII, 25%). The results of this study provide strong evidence of phylogeographic structuring of E. coli O157 populations, suggesting divergent evolution of enterohemorrhagic E. coli O157 in Australia and the United States. 相似文献
93.
Capsule: Feather stable isotope analysis suggests summering of so‐called ‘northern trumpeting’ Bullfinches in Denmark. 相似文献
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95.
We have examined the properties of intramolecular G-quadruplexes in which the G3 tracts are separated by single base loops. The most stable complex contained 1',2'-dideoxyribose in all three loops, while loops containing T and C were slightly less stable (by about 2 degrees C). Quadruplexes containing loops with single A residues were less stable by 8 degrees C for each T to A substitution. These folded sequences display similar CD spectra, which are consistent with the formation of parallel stranded complexes with double-chain reversal loops. These results demonstrate that loop sequence, and not just length, affects quadruplex stability. 相似文献
96.
The spectacled flying fox, Pteropus conspicillatus, is listed as vulnerable in Australia and is under threat from numerous impacts. Primers to amplify eight co-dominant microsatellite
loci were designed for Pteropus conspicillatus, based on an enriched genomic library. Four loci were monomorphic in this species while the remaining four loci were highly
polymorphic with 16–23 alleles. Two of the four monomorphic loci were found to be polymorphic in Pteropus alecto, a closely related congener. All but one of the six polymorphic loci were in Hardy Weinberg equilibrium. Additionally, six
microsatellite loci isolated for Pteropus rodricensis were tested against individuals of P. conspicillatus with all loci amplifying reliably. These loci will be used to investigate population genetic structure in the vulnerable
spectacled flying fox. 相似文献
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99.
Gavin J Knott Yee Seng Chong Daniel M Passon Xue-hai Liang Evelyne Deplazes Maria
R Conte Andrew
C Marshall Mihwa Lee Archa
H Fox Charles
S Bond 《Nucleic acids research》2022,50(1):522
The Drosophila behaviour/human splicing (DBHS) proteins are a family of RNA/DNA binding cofactors liable for a range of cellular processes. DBHS proteins include the non-POU domain-containing octamer-binding protein (NONO) and paraspeckle protein component 1 (PSPC1), proteins capable of forming combinatorial dimers. Here, we describe the crystal structures of the human NONO and PSPC1 homodimers, representing uncharacterized DBHS dimerization states. The structures reveal a set of conserved contacts and structural plasticity within the dimerization interface that provide a rationale for dimer selectivity between DBHS paralogues. In addition, solution X-ray scattering and accompanying biochemical experiments describe a mechanism of cooperative RNA recognition by the NONO homodimer. Nucleic acid binding is reliant on RRM1, and appears to be affected by the orientation of RRM1, influenced by a newly identified ‘β-clasp’ structure. Our structures shed light on the molecular determinants for DBHS homo- and heterodimerization and provide a basis for understanding how DBHS proteins cooperatively recognize a broad spectrum of RNA targets. 相似文献
100.
José Manuel Fernández-Ábalos Helen Fox Chris Pitt Brian Wells & John H. Doonan 《Molecular microbiology》1998,27(1):121-130
Green fluorescent protein (GFP) is a useful reporter to follow the in vivo behaviour of proteins, but the wild-type gfp gene does not function in many organisms, including many plants and filamentous fungi. We show that codon-modified forms of gfp , produced for use in plants, function effectively in Aspergillus nidulans both as gene expression reporters and as vital reporters for protein location. To demonstrate the use of these modified gfp s as reporter genes we have used fluorescence to follow ethanol-induced GFP expression from the alcA promoter. Translational fusions with the modified gfp were used to follow protein location in living cells; plant ER-retention signals targeted GFP to the endoplasmic reticulum, whereas fusion to the GAL4 DNA-binding domain targeted it to the nucleus. Nuclear-targeted GFP allowed real-time observation of nuclear movement and division. These modified gfp genes should provide useful markers to follow gene expression, organelle behaviour and protein trafficking in real time. 相似文献