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981.
Cinara L. Gonçalves Gislaine T. Rezin Gabriela K. Ferreira Isabela C. Jeremias Mariane R. Cardoso Samira S. Valvassori Bruna J. P. Munhoz Gabriela D. Borges Bruno N. Bristot Daniela D. Leffa Vanessa M. Andrade João Quevedo Emilio L. Streck 《Molecular and cellular biochemistry》2013,380(1-2):171-176
Obesity is a chronic and multifactorial disease, whose prevalence is increasing in many countries. Pharmaceutical strategies for the treatment of obesity include drugs that regulate food intake, thermogenesis, fat absorption, and fat metabolism. Fenproporex is the second most commonly consumed amphetamine-based anorectic worldwide; this drug is rapidly converted in vivo into amphetamine, which is associated with neurotoxicity. In this context, the present study evaluated DNA damage parameters in the peripheral blood of young and adult rats submitted to an acute administration and chronic administration of fenproporex. In the acute administration, both young and adult rats received a single injection of fenproporex (6.25, 12.5 or 25 mg/kg i.p.) or vehicle. In the chronic administration, both young and adult rats received one daily injection of fenproporex (6.25, 12.5, or 25 mg/kg i.p.) or Tween for 14 days. 2 h after the last injection, the rats were killed by decapitation and their peripheral blood removed for evaluation of DNA damage parameters by alkaline comet assay. Our study showed that acute administration of fenproporex in young and adult rats presented higher levels of damage index and frequency in the DNA. However, chronic administration of fenproporex in young and adult rats did not alter the levels of DNA damage in both parameters of comet assay. The present findings showed that acute administration of fenproporex promoted damage in DNA, in both young and adult rats. Our results are consistent with other reports which showed that other amphetamine-derived drugs also caused DNA damage. We suggest that the activation of an efficient DNA repair mechanism may occur after chronic exposition to fenproporex. Our results are consistent with other reports that showed some amphetamine-derived drugs also caused DNA damage. 相似文献
982.
Cibelle Mariano Inês Palmela Pedro Pereira Adelaide Fernandes Ana Sofia Falcão Filipa Lourenço Cardoso Ana Rita Vaz Alexandre Rainha Campos António Gonçalves-Ferreira Kwang Sik Kim Dora Brites Maria Alexandra Brito 《Cell and tissue research》2013,351(3):397-407
Tricellulin is a tight junction (TJ) protein, which is not only concentrated at tricellular contacts but also present at bicellular contacts between epithelial tissues. We scrutinized the brain for tricellulin expression in endothelial and neural cells by using real-time polymerase chain reaction, Western blot and immunohistochemical and immunocytochemical analysis of cultured brain cells and paraffin sections of brain. Tricellulin mRNA was detected in primary cultures and in a cell line of human brain microvascular endothelial cells. Protein expression was confirmed by Western blot and immunofluorescence analysis, which further highlighted the localization of tricellulin in the cell membrane at tricellular and along bicellular contacts, and in the nucleus and perinuclear region. Compared with the well-studied TJ protein, zonula occludens-1, tricellulin expression was less marked at the cell membrane but more evident in the nuclear and perinuclear regions. The presence of tricellulin in cultured endothelial cells was corroborated by immunohistochemical and immunofluorescence staining in brain blood vessels, where it was colocalized with another TJ protein, claudin-5. Tricellulin mRNA was detected in neurons and astrocytes, whereas protein expression was observed in astrocytes but not in neurons, as shown by immunofluorescence analysis. This study reveals the presence and subcellular distribution of tricellulin in brain endothelial cells, both in vitro and in situ and its colocalization with other relevant TJ proteins. Moreover, it demonstrates the expression of the protein in astrocytes opening new avenues for future research to establish the biological significance of tricellulin expression in glial cells. 相似文献
983.
Tatiana Tavares Carrijo Mário Luís Garbin Wellerson Picanço Leite Cláudia Barbieri Ferreira Mendonça Roberto Lourenço Esteves Vania Gonçalves-Esteves 《Plant Systematics and Evolution》2013,299(7):1275-1283
Pollen morphology is an important source of information to increase systematic resolution in Asteraceae, especially in Vernonieae. Aiming to investigate if palynological traits give support to Caatinganthus, Strophopappus and Xiphochaeta as separate genera from Stilpnopappus, we used cluster analysis followed by a test of group sharpness. Further, ordination analysis was applied to detect informative pollen traits associated with the revealed groups. The analyses evidenced five groups: (G1) Caatinganthus rubropappus as a single-species group; (G2) species of Stilpnopappus; (G3) Xiphochaeta aquatica as a single-species group; (G4) Strophopappus bicolor, S. glomeratus, S. villosus, S. ferrugineus, S. pohlii and S. speciosus; (G5) Strophopappus bullatus and S. regnelli. The interruption in the middle of the muri in apertural lacunae explains the single-species group Caatinganthus rubropappus. The thickness of sexine, the type of apertures (porate or colporate), and spine dimensions (length, thickness and distance from each other) are the traits explaining differences between species of Stilpnopappus and Strophopappus. Equatorial lacunae give support to Xiphochaeta aquatica as a single-species group, despite the smaller size of pollen grains of this species as compared to the others species analyzed. The differences among pollen morphology give support to Caatinganthus, Stilpnopappus, Strophopappus and Xiphochaeta as genera according to the taxonomic classification currently accepted. The used approach was efficient to reveal individual pollen traits informative to explain the sharp groups, and was an effective alternative to the use of “pollen types”. 相似文献
984.
Residual dipolar couplings (RDCs) were used as restraints in fully solvated molecular dynamics simulations of reduced substrate- and carbonmonoxy-bound cytochrome P450(cam) (CYP101A1), a 414-residue soluble monomeric heme-containing camphor monooxygenase from the soil bacterium Pseudomonas putida. The (1)D(NH) residual dipolar couplings used as restraints were measured in two independent alignment media. A soft annealing protocol was used to heat the starting structures while incorporating the RDC restraints. After production dynamics, structures with the lowest total violation energies for RDC restraints were extracted to identify ensembles of conformers accessible to the enzyme in solution. The simulations result in substrate orientations different from that seen in crystallographic structures and a more open and accessible enzyme active site and largely support previously reported differences between the open and closed states of CYP101A1. 相似文献
985.
Almeida Júnior Edivan S. Martínez Aingeru Gonçalves Ana Lúcia Canhoto Cristina 《Hydrobiologia》2020,847(16):3427-3435
Hydrobiologia - Freshwater salinization is a matter of major global concern due to its consequences on the aquatic biota and ecosystems functioning. Salt contamination negatively affects the leaf... 相似文献
986.
987.
de Freitas Maria de Fátima Matos Hortêncio Lucas C. de Albuquerque Tiago Lima Rocha Maria Valderez Ponte Gonçalves Luciana Rocha Barros 《Bioprocess and biosystems engineering》2020,43(4):711-722
Bioprocess and Biosystems Engineering - β-Galactosidase was produced by the yeast Kluyveromyces lactis NRRL Y1564 in cheese whey supplemented with yeast extract under the optimal temperature... 相似文献
988.
Fabrício R. Lopes Daudi Jjingo Carlos R. M. da Silva Alan C. Andrade Pierre Marraccini Jo?o B. Teixeira Marcelo F. Carazzolle Gon?alo A. G. Pereira Luiz Filipe P. Pereira André L. L. Vanzela Lu Wang I. King Jordan Claudia M. A. Carareto 《PloS one》2013,8(11)
Plant genomes are massively invaded by transposable elements (TEs), many of which are located near host genes and can thus impact gene expression. In flowering plants, TE expression can be activated (de-repressed) under certain stressful conditions, both biotic and abiotic, as well as by genome stress caused by hybridization. In this study, we examined the effects of these stress agents on TE expression in two diploid species of coffee, Coffea canephora and C. eugenioides, and their allotetraploid hybrid C. arabica. We also explored the relationship of TE repression mechanisms to host gene regulation via the effects of exonized TE sequences. Similar to what has been seen for other plants, overall TE expression levels are low in Coffea plant cultivars, consistent with the existence of effective TE repression mechanisms. TE expression patterns are highly dynamic across the species and conditions assayed here are unrelated to their classification at the level of TE class or family. In contrast to previous results, cell culture conditions per se do not lead to the de-repression of TE expression in C. arabica. Results obtained here indicate that differing plant drought stress levels relate strongly to TE repression mechanisms. TEs tend to be expressed at significantly higher levels in non-irrigated samples for the drought tolerant cultivars but in drought sensitive cultivars the opposite pattern was shown with irrigated samples showing significantly higher TE expression. Thus, TE genome repression mechanisms may be finely tuned to the ideal growth and/or regulatory conditions of the specific plant cultivars in which they are active. Analysis of TE expression levels in cell culture conditions underscored the importance of nonsense-mediated mRNA decay (NMD) pathways in the repression of Coffea TEs. These same NMD mechanisms can also regulate plant host gene expression via the repression of genes that bear exonized TE sequences. 相似文献
989.
Ana Maria Baptista Menezes Joseph Murray Mitzi László Fernando C. Wehrmeister Pedro C. Hallal Helen Gon?alves Maria Cecilia F. Assun??o Carolina Baptista Menezes Fernando C. Barros 《PloS one》2013,8(11)