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991.
A tight balance between natural selection and gene flow in a southern African arid-zone endemic bird
Ribeiro ÅM Lloyd P Bowie RC 《Evolution; international journal of organic evolution》2011,65(12):3499-3514
Gene flow is traditionally thought to be antagonistic to population differentiation and local adaptation. However, recent studies have demonstrated that local adaptation can proceed provided that selection is greater than the homogenizing effects of gene flow. We extend these initial studies by combining ecology (climate), phenotype (body size), physiological genetics (oxidative phosphorylation genes), and neutral loci (nuclear microsatellites and introns) to test whether selection can counter-balance gene flow and hence promote local adaptation in a bird whose distribution spans an aridity gradient. Our results show that the Karoo scrub-robin's climatic niche is spatially structured, providing the potential for local adaptation to develop. We found remarkably discordant patterns of divergence among mtDNA, morphology, and neutral loci. For the mitochondrial genes, two amino acid replacements, strong population structure and reduced gene flow were associated with the environmental gradient separating western coastal sites from the interior of southern Africa. In contrast, morphology and the neutral loci exhibited variation independent of environmental variables, and revealed extensive levels of gene flow across the aridity gradient, 50 times larger than the estimates for mitochondrial genes. Together, our results suggest that selective pressures on physiology, mediated by the mitochondrial genome, may well be a common mechanism for facilitating local adaptation to new climatic conditions. 相似文献
992.
Julio Cesar S. Sales Aline M. de Castro Bernardo D. Ribeiro 《Biocatalysis and Biotransformation》2020,38(6):457-468
AbstractYarrowia lipolytica is a yeast that presents high biotechnological potential due to its ability to produce many metabolites, among them lipases and esterases, which are important industrial biocatalysts. Since Brazil is an agroindustrial country, it generates an enormous diversity of residues or byproducts that can be used as a platform for biomolecules production. This work aims to evaluate lipase and esterase production by Y. lipolytica via solid-state fermentation using soybean bran and soybean bran supplemented with watermelon peels in different contents, and subsequent use of the enzyme extracts for poly(ethylene terephthalate) (PET) hydrolysis. Supplementation of watermelon peels in the lowest content led to an improvement of lipase activity in almost 31%, reaching 75.22?U g?1. Esterase productivity was 1.5-fold higher when 20?wt% of watermelon peels were added to the media culture. Timecourse evaluation of enzymes production showed a maximum lipase activity in 14?h and similar esterase activity in 14 and 20?h of fermentation. Proteases production were also intensified in supplemented samples. Enzymes produced with 5?wt% watermelon peels supplementation led to higher terephthalic acid concentration (up to 42.02?µmol L?1) during PET depolymerization. Results suggest a great potential of enzyme production in low cost fermentative media to act as biocatalysts in PET hydrolysis reactions. 相似文献
993.
Thaylise de Cassia Santos Przepiura Aryelle M. Navarro Rafaela da Rosa Ribeiro Jos R. Gomes Karina V. Pitthan Maria A. de Miranda Soares 《Cell biology international》2020,44(10):1981-1990
Programmed cell death is involved with the degeneration/remodeling of larval tissues and organs during holometabolous development. The midgut is a model to study the types of programmed cell death associated with metamorphosis because its structure while degenerating is a substrate for the formation of the adult organ. Another model is the salivary glands from dipteran because their elimination involves different cell death modes. This study aimed to investigate the models of programmed cell death operating during midgut replacement and salivary gland histolysis in Bradysia hygida. We carried out experiments of real‐time observations, morphological analysis, glycogen detection, filamentous‐actin localization, and nuclear acridine orange staining. Our findings allow us to establish that an intact actin cytoskeleton is required for midgut replacement in B. hygida and nuclear condensation and acridine orange staining precede the death of the larval cells. Salivary glands in histolysis present cytoplasmic blebbing, nuclear retraction, and acridine orange staining. This process can be partially reproduced in vitro. We propose that the larval midgut death involves autophagic and apoptotic features and apoptosis is a mechanism involved with salivary gland histolysis. 相似文献
994.
Bruno Frederico Aguilar Calegare Augusto Azzolini Julia Ribeiro da Silva Vallim Edson Guimares Lo Turco Priscila Farias Tempaku Vanessa Cavalcante da Silva Sergio Tufik Vnia D'Almeida 《Genesis (New York, N.Y. : 2000)》2020,58(3-4)
A previous animal study by our group found that sleep deprivation during preimplantation was associated with decreased pregnancy maintenance. Given its impact on human society, we aimed in the current study to assess whether sleep deprivation affects blastocyst gene expression and/or the implantation process. For this, pregnant mice (gestational day 0 [GD 0]) were assigned into paradoxical sleep deprivation (SD, 72 hr; multiple platform method) and, a control (CT) group. Animals were euthanized on GD 3.5 and blood, uterus (embryos) and fallopian tube were collected. Then, 89% of CT presented blastocysts in the uterus versus 25% from SD group. Compared to CT, SD presented lighter relative uterus weight, increased plasma concentrations of corticosterone and testosterone, decreased concentrations of progesterone and luteinizing hormone, but no statistical differences in plasma concentrations of 17β‐estradiol and follicle stimulating hormone. There were no differences in uterus and blastocyst gene expression related to embryo implantation and development, and no alteration in blastocysts global DNA methylation. Considering this, the decreased pregnancy maintenance after sleep deprivation seems not to be associated with implantation losses or developmental problems related to the blastocysts. It is likely that complications in morula development and/or its movement through the fallopian tubes affect the pregnancy rate, since only 25% of SD females presented a blastocyst on the GD 3.5. In fact, three out of four females without blastocysts in the uterus presented morula in the fallopian tubes due to a phase delay. Additionally, we suggest that the observed hormonal changes may play a role in this outcome. 相似文献
995.
de Castro e Silva Priscila Pereira Lívio Antônio Silva Lago Amanda Maria Teixeira dos Reis Michele Valquíria de Rezende Édila Maria Carvalho Gabriel Ribeiro Oliveira Juliano Elvis Marconcini José Manoel 《Food biophysics》2020,15(1):153-153
Food Biophysics - The original version of this article unfortunately contained errors. The author name “Michele Valquíria dos Reis” and affiliation were incorrect. 相似文献
996.
Klanovicz Natalia Camargo Aline Frumi Stefanski Fábio Spitza Zanivan Jessica Scapini Thamarys Pollon Rafaela Warken Andressa Paliga Letícia Preczeski Karina Paula Ribeiro Anderson André Genro Alves Garda-Buffon Jaqueline Fongaro Gislaine Treichel Helen 《Bioprocess and biosystems engineering》2020,43(2):261-272
Bioprocess and Biosystems Engineering - Enzymes are becoming tools in industrial processes because of several advantages, including activity in mild environmental conditions, and high specificity.... 相似文献
997.
Rommel Thiago Jucá Ramos Adriana Ribeiro Carneiro Siomar de Castro Soares Anderson Rodrigues dos Santos Sintia Almeida Luis Guimar?es Flávia Figueira Eudes Barbosa Andreas Tauch Vasco Azevedo Artur Silva 《Microbial biotechnology》2013,6(2):150-156
New sequencing platforms have enabled rapid decoding of complete prokaryotic genomes at relatively low cost. The Ion Torrent platform is an example of these technologies, characterized by lower coverage, generating challenges for the genome assembly. One particular problem is the lack of genomes that enable reference-based assembly, such as the one used in the present study, Corynebacterium pseudotuberculosis biovar equi, which causes high economic losses in the US equine industry. The quality treatment strategy incorporated into the assembly pipeline enabled a 16-fold greater use of the sequencing data obtained compared with traditional quality filter approaches. Data preprocessing prior to the de novo assembly enabled the use of known methodologies in the next-generation sequencing data assembly. Moreover, manual curation was proved to be essential for ensuring a quality assembly, which was validated by comparative genomics with other species of the genus Corynebacterium. The present study presents a modus operandi that enables a greater and better use of data obtained from semiconductor sequencing for obtaining the complete genome from a prokaryotic microorganism, C. pseudotuberculosis, which is not a traditional biological model such as Escherichia coli. 相似文献
998.
Dirce Maria Carraro Maria Aparecida Azevedo Koike Folgueira Bianca Cristina Garcia Lisboa Eloisa Helena Ribeiro Olivieri Ana Cristina Vitorino Krepischi Alex Fiorini de Carvalho Louise Danielle de Carvalho Mota Renato David Puga Maria do Socorro Maciel Rodrigo Augusto Depieri Michelli Eduardo Carneiro de Lyra Stana Helena Giorgi Grosso Fernando Augusto Soares Maria Isabel Alves de Souza Waddington Achatz Helena Brentani Carlos Alberto Moreira-Filho Maria Mitzi Brentani 《PloS one》2013,8(3)
999.
Pedro H. N. Aguiar Carolina Furtado Bruno M. Repolês Grazielle A. Ribeiro Isabela C. Mendes Eduardo F. Peloso Fernanda R. Gadelha Andrea M. Macedo Glória R. Franco Sérgio D. J. Pena Santuza M. R. Teixeira Leda Q. Vieira Alessandra A. Guarneri Luciana O. Andrade Carlos R. Machado 《PLoS neglected tropical diseases》2013,7(6)
The main consequence of oxidative stress is the formation of DNA lesions, which can result in genomic instability and lead to cell death. Guanine is the base that is most susceptible to oxidation, due to its low redox potential, and 8-oxoguanine (8-oxoG) is the most common lesion. These characteristics make 8-oxoG a good cellular biomarker to indicate the extent of oxidative stress. If not repaired, 8-oxoG can pair with adenine and cause a G:C to T:A transversion. When 8-oxoG is inserted during DNA replication, it could generate double-strand breaks, which makes this lesion particularly deleterious. Trypanosoma cruzi needs to address various oxidative stress situations, such as the mammalian intracellular environment and the triatomine insect gut where it replicates. We focused on the MutT enzyme, which is responsible for removing 8-oxoG from the nucleotide pool. To investigate the importance of 8-oxoG during parasite infection of mammalian cells, we characterized the MutT gene in T. cruzi (TcMTH) and generated T. cruzi parasites heterologously expressing Escherichia coli MutT or overexpressing the TcMTH enzyme. In the epimastigote form, the recombinant and wild-type parasites displayed similar growth in normal conditions, but the MutT-expressing cells were more resistant to hydrogen peroxide treatment. The recombinant parasite also displayed significantly increased growth after 48 hours of infection in fibroblasts and macrophages when compared to wild-type cells, as well as increased parasitemia in Swiss mice. In addition, we demonstrated, using western blotting experiments, that MutT heterologous expression can influence the parasite antioxidant enzyme protein levels. These results indicate the importance of the 8-oxoG repair system for cell viability. 相似文献
1000.
Xutao Deng Ester C. Sabino Edecio Cunha-Neto Antonio L. Ribeiro Barbara Ianni Charles Mady Michael P. Busch Mark Seielstad the REDSII Chagas study group from the NHLBI Retrovirus Epidemiology Donor Study-II International Component 《PloS one》2013,8(11)