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991.
Phylogeographical patterns in Coenosia attenuata (Diptera: Muscidae): a widespread predator of insect species associated with greenhouse crops
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![点击此处可从《Biological journal of the Linnean Society. Linnean Society of London》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Sofia G. Seabra Patrícia G. Brás Joana Martins Renata Martins Nigel Wyatt Jalal Shirazi Maria Teresa Rebelo José Carlos Franco Célia Mateus Elisabete Figueiredo Octávio S. Paulo 《Biological journal of the Linnean Society. Linnean Society of London》2015,114(2):308-326
The tiger‐fly Coenosia attenuata is a globally widespread predatory fly which is not only associated with greenhouse crops, but also occurs in open fields. It is a potential control agent against some of the more common pests in these crops. Assessing the genetic structure and gene flow patterns may be important for planning crop protection strategies and for understanding the historical processes that led to the present distribution of genetic lineages within this species. In the present study, the phylogeographical patterns of this species, based on mitochondrial cytochrome oxidase I and nuclear white and elongation factor‐1α genes, are described, revealing relatively low genetic diversity and weak genetic structure associated with a recent and sudden population expansion of the species. The geographical distribution of mitochondrial haplotypes indicates the Mediterranean as the most likely region of origin of the species. Some dispersal patterns of the species are also revaled, including at least three independent colonizations of North and South America: one from Middle East to North America with a strong bottleneck event, another from Europe to South America (Chile), with both likely to be a result of unintentional introduction, and a third one of still undetermined origin to South America (Ecuador). © 2014 The Linnean Society of London, Biological Journal of the Linnean Society, 2015, 114 , 308–326. 相似文献
992.
993.
Assessing the alignment of sexual and natural selection using radiomutagenized seed beetles
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![点击此处可从《Journal of evolutionary biology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
A major unsolved question in evolutionary biology concerns the relationship between natural and sexual selection. Sexual selection might augment natural selection, for example if mutations that harm female fecundity also reduce male mating success. Conversely, sexual selection might favour traits that impair naturally selected fitness components. We induced detrimental mutations in Callosobruchus maculatus beetles using X‐ray irradiation and then experimentally measured the effect of precopulatory sexual selection on offspring number and survival rate. Sexual selection treatment had a negative effect on egg‐to‐adult survivorship, although the number of progeny reaching adulthood was unaffected, perhaps because eggs and juveniles that failed to develop lessened competition on the survivors. We hypothesize that the negative effect of sexual selection arose because sexually competitive males transmitted a smaller nuptial gift or carried alleles that conferred reduced survival. Although we found no evidence that sexual selection on males can purge alleles that are detrimental to naturally selected fitness components, such benefits might exist in other environmental or genetic contexts. 相似文献
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995.
Juan Jimenez Caia D. S. Duncan María Gallardo Juan Mata Antonio J. Perez-Pulido 《DNA research》2015,22(6):439-449
Genome annotation, assisted by computer programs, is one of the great advances in modern biology. Nevertheless, the in silico identification of small and complex coding sequences is still challenging. We observed that amino acid sequences inferred from coding—but rarely from non-coding—DNA sequences accumulated alignments in low-stringency BLAST searches, suggesting that this alignments accumulation could be used to highlight coding regions in sequenced DNA. To investigate this possibility, we developed a computer program (AnABlast) that generates profiles of accumulated alignments in query amino acid sequences using a low-stringency BLAST strategy. To validate this approach, all six-frame translations of DNA sequences between every two annotated exons of the fission yeast genome were analysed with AnABlast. AnABlast-generated profiles identified three new copies of known genes, and four new genes supported by experimental evidence. New pseudogenes, ancestral carboxyl- and amino-terminal subtractions, complex gene rearrangements, and ancient fragments of mitDNA and of bacterial origin, were also inferred. Thus, this novel in silico approach provides a powerful tool to uncover new genes, as well as fossil-coding sequences, thus providing insight into the evolutionary history of annotated genomes. 相似文献
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Gissela Borrego-Soto Rocío Ortiz-López Augusto Rojas-Martínez 《Genetics and molecular biology》2015,38(4):420-432
Breast cancer is the most common malignancy in women. Radiotherapy is frequently used
in patients with breast cancer, but some patients may be more susceptible to ionizing
radiation, and increased exposure to radiation sources may be associated to radiation
adverse events. This susceptibility may be related to deficiencies in DNA repair
mechanisms that are activated after cell-radiation, which causes DNA damage,
particularly DNA double strand breaks. Some of these genetic susceptibilities in
DNA-repair mechanisms are implicated in the etiology of hereditary breast/ovarian
cancer (pathologic mutations in the BRCA 1 and 2 genes), but other
less penetrant variants in genes involved in sporadic breast cancer have been
described. These same genetic susceptibilities may be involved in negative
radiotherapeutic outcomes. For these reasons, it is necessary to implement methods
for detecting patients who are susceptible to radiotherapy-related adverse events.
This review discusses mechanisms of DNA damage and repair, genes related to these
functions, and the diagnosis methods designed and under research for detection of
breast cancer patients with increased radiosensitivity. 相似文献
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N Blavet H Blavet A Muyle J K?fer R Cegan C Deschamps N Zemp S Mousset S Aubourg R Bergero D Charlesworth R Hobza A Widmer GAB Marais 《BMC genomics》2015,16(1)