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951.
Detection of Viral DNA Sequences in Adenovirus-Transformed Cells by In Situ Hybridization 总被引:1,自引:1,他引:0
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![点击此处可从《Journal of virology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Cytological preparations of cells transformed by members of three groups of human adenoviruses, adenovirus 12, 7, and 2, were annealed with radioactive complementary RNA (cRNA) (4 x 10(7) to 4.5 x 10(7) dpm/mug) prepared by copying viral DNA with the Escherichia coli DNA-directed RNA polymerase. These in situ hybridizations detected adenovirus-specific DNA sequences in interphase nuclei when transformed cells were annealed with homologous viral cRNA, but not with heterologous viral cRNA. The highest autoradiographic grain counts were found over adenovirus 7-transformed cell nuclei, next over adenovirus 12-, and the lowest over adenovirus 2-transformed cell nuclei. This is the same order as found by reassociation kinetic measurements (K. Fujinaga and M. Green, unpublished data). 相似文献
952.
953.
Nicolas Brucato Veronica Fernandes Stéphane Mazières Pradiptajati Kusuma Murray P. Cox Joseph Wainaina Ng’ang’a Mohammed Omar Marie-Claude Simeone-Senelle Coralie Frassati Farida Alshamali Bertrand Fin Anne Boland Jean-Francois Deleuze Mark Stoneking Alexander Adelaar Alison Crowther Nicole Boivin Luisa Pereira François-Xavier Ricaut 《American journal of human genetics》2018,102(1):58-68
954.
Pia Gruber Filipe Carvalho Marco P. C. Marques Brian O'Sullivan Fabiana Subrizi Dragana Dobrijevic John Ward Helen C. Hailes Pedro Fernandes Roland Wohlgemuth Frank Baganz Nicolas Szita 《Biotechnology and bioengineering》2018,115(3):586-596
955.
Ananza M. Rabello Catherine L. Parr Antônio C. M. Queiroz Danielle L. Braga Graziele S. Santiago Carla R. Ribas 《Biotropica》2018,50(1):39-49
Changes in land use strongly influence habitat attributes (e.g., herbaceous ground cover and tree richness) and can consequently affect ecological functions. Most studies have focused on the response of these ecological functions to land‐use changes within only a single vegetation type. These studies have often focused solely on agricultural conversion of forests, making it nearly impossible to draw general conclusions across other vegetation types or with other land‐use changes (e.g., afforestation). We examined the consequences of agricultural conversion for seed removal by ants in native grassland, savanna, and savanna‐forest habitats that had been transformed to planted pastures (Brachiaria decumbens) and tree plantations (Eucalyptus spp.) and explored if changes in seed removal were correlated with differences in habitat attributes between habitat types. We found that land‐use changes affected seed removal across the tree cover gradient and that the magnitude of impact was influenced by similarity in habitat attributes between native and converted habitats, being greater where there was afforestation (Eucalyptus spp in grassland and savanna). Herbaceous ground cover, soil hardness, and tree richness were the most important habitat attributes that correlated with differences in seed removal. Our results reveal that the magnitude of impact of land‐use changes on seed removal varies depending on native vegetation type and is associated with the type of habitat attribute change. Our findings have implications for biodiversity in tropical grassy systems: afforestation can have a greater detrimental impact on ecological function than tree loss. 相似文献
956.
Primary familial brain calcification with a novel SLC20A2 mutation: Analysis of PiT‐2 expression and localization
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![点击此处可从《Journal of cellular physiology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
957.
Cynthia Fernandes Pinto da Luz Adriana de Oliveira Fidalgo Shirley Ambrosia Yovetti Silva Sandra dos Santos Rodrigues Roberta Cornélio Ferreira Nocelli 《Grana》2018,57(5):377-400
Honey and bee bread samples from storage pots of Melipona quadrifasciata anthidioides were collected monthly from April 2015 to May 2016 in the Mogi Guaçu Biological Reserve (22º 10? S, 47º 11? W). The flora in the site is characteristic of the Atlantic Forest with preserved areas of savanna-like vegetation surrounded by commercial forests, orchards and various crops of exotic and native plants. Samples were analysed with the use of melissopalynological methodology and 46 pollen types from 38 genera and 30 families were identified in 25 honey samples. Fabaceae, Asteraceae, Myrtaceae, Sapindaceae showed the greatest pollen richness in honey. Predominant nectariferous pollen types were Anadenanthera, Cordia, Eucalyptus, Mimosa scabrella, Schefflera, Sida, Serjania and Vernonia. Twenty-eight types of pollen from 21 genera and 19 families were identified in 22 bee bread samples. Fabaceae, Asteraceae and Myrtaceae showed the highest pollen richness. Anadenanthera, Cecropia, Eucalyptus, Melastomataceae, Mimosa scabrella, Mimosa verrucosa and Myrcia were the most frequent polliniferous pollen types. Principal component analysis (PCA) demonstrated that honey and pollen samples formed two main groups of similarity, mainly due to Eucalyptus’ nectar and pollen of Melastomataceae, respectively. Melipona quadrifasciata anthidioides collected nectar and pollen from the preserved areas as well as in the secondary and ‘ruderal’ vegetation and in cultivated forests/fields, suggesting their importance as pollinators both of native flora and exotic species. The use of trophic resources of plants grown with pesticides is a concern for the conservation of these species of bee and should be better studied. 相似文献
958.
959.
Interference with ethylene perception at receptor level sheds light on auxin and transcriptional circuits associated with the climacteric ripening of apple fruit (Malus x domestica Borkh.)
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![点击此处可从《The Plant journal : for cell and molecular biology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Marco Moretto Alberto Ferrarini Paola Tononi Brian Farneti Nicola Busatto Urska Vrhovsek Alessandra dal Molin Carla Avanzato Franco Biasioli Luca Cappellin Matthias Scholz Riccardo Velasco Livio Trainotti Massimo Delledonne Fabrizio Costa 《The Plant journal : for cell and molecular biology》2016,88(6):963-975
960.
Ancient DNA reveals differences in behaviour and sociality between brown bears and extinct cave bears
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![点击此处可从《Molecular ecology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Gloria G. Fortes Aurora Grandal‐d'Anglade Ben Kolbe Daniel Fernandes Ioana N. Meleg Ana García‐Vázquez Ana C. Pinto‐Llona Silviu Constantin Trino J. de Torres Jose E. Ortiz Christine Frischauf Gernot Rabeder Michael Hofreiter Axel Barlow 《Molecular ecology》2016,25(19):4907-4918
Ancient DNA studies have revolutionized the study of extinct species and populations, providing insights on phylogeny, phylogeography, admixture and demographic history. However, inferences on behaviour and sociality have been far less frequent. Here, we investigate the complete mitochondrial genomes of extinct Late Pleistocene cave bears and middle Holocene brown bears that each inhabited multiple geographically proximate caves in northern Spain. In cave bears, we find that, although most caves were occupied simultaneously, each cave almost exclusively contains a unique lineage of closely related haplotypes. This remarkable pattern suggests extreme fidelity to their birth site in cave bears, best described as homing behaviour, and that cave bears formed stable maternal social groups at least for hibernation. In contrast, brown bears do not show any strong association of mitochondrial lineage and cave, suggesting that these two closely related species differed in aspects of their behaviour and sociality. This difference is likely to have contributed to cave bear extinction, which occurred at a time in which competition for caves between bears and humans was likely intense and the ability to rapidly colonize new hibernation sites would have been crucial for the survival of a species so dependent on caves for hibernation as cave bears. Our study demonstrates the potential of ancient DNA to uncover patterns of behaviour and sociality in ancient species and populations, even those that went extinct many tens of thousands of years ago. 相似文献