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91.
Amanda Santos Gusmão Lucas Silva Abreu Josean Fechine Tavares Humberto Fonseca de Freitas Samuel Silva da Rocha Pita Elda Gonçalves dos Santos Ivo Santana Caldas André Alexandre Vieira Eliane Oliveira Silva 《化学与生物多样性》2021,18(10):e2100493
Hundreds of millions of people worldwide are affected by Chagas’ disease caused by Trypanosoma cruzi. Since the current treatment lack efficacy, specificity, and suffers from several side-effects, novel therapeutics are mandatory. Natural products from endophytic fungi have been useful sources of lead compounds. In this study, three lactones isolated from an endophytic strain culture were in silico evaluated for rational guidance of their bioassay screening. All lactones displayed in vitro activity against T. cruzi epimastigote and trypomastigote forms. Notably, the IC50 values of (+)-phomolactone were lower than benznidazole (0.86 vs. 30.78 μM against epimastigotes and 0.41 vs. 4.88 μM against trypomastigotes). Target-based studies suggested that lactones displayed their trypanocidal activities due to T. cruzi glyceraldehyde-3-phosphate dehydrogenase (TcGAPDH) inhibition, and the binding free energy for all three TcGAPDH-lactone complexes suggested that (+)-phomolactone has a lower score value (−3.38), corroborating with IC50 assays. These results highlight the potential of these lactones for further anti-T. cruzi drug development. 相似文献
92.
Olwen M. Grace Oscar A. Pérez-Escobar Eve J. Lucas Maria S. Vorontsova Gwilym P. Lewis Barnaby E. Walker Lúcia G. Lohmann Sandra Knapp Peter Wilkie Tiina Sarkinen Iain Darbyshire Eimear Nic Lughadha Alexandre Monro Yannick Woudstra Sebsebe Demissew A. Muthama Muasya Sandra Díaz William J. Baker Alexandre Antonelli 《Trends in plant science》2021,26(5):433-441
93.
Calmasini Fabiano B. Alexandre Eduardo C. Oliveira Mariana G. Silva Fábio H. Soares António G. Costa Soraia K.P. Antunes Edson 《Journal of physiology and biochemistry》2021,77(4):557-564
Journal of Physiology and Biochemistry - Lipopolysaccharide (LPS) is a component of gram-negative bacteria wall that elicits inflammatory response in the host through the toll-like receptor 4... 相似文献
94.
Joseana Vieira Flávia Cristina de Paula Freitas Alexandre Santos Cristino Daniel Guariz Pinheiro Luiz Roberto Aguiar Marcela Aparecida Framartino Bezerra Laure Lívia Maria Rosatto Moda Zilá Luz Paulino Simões Angel Roberto Barchuk 《Biochimica et Biophysica Acta (BBA) - Gene Regulatory Mechanisms》2021,1864(9):194732
Brain differential morphogenesis in females is one of the major phenotypic manifestations of caste development in honey bees. Brain diphenism appears at the fourth larval phase as a result of the differential feeding regime developing females are submitted during early phases of larval development. Here, we used a forward genetics approach to test the early brain molecular response to differential feeding leading to the brain diphenism observed at later developmental phases. Using RNA sequencing analysis, we identified 53 differentially expressed genes (DEGs) between the brains of queens and workers at the third larval phase. Since miRNAs have been suggested to play a role in caste differentiation after horizontal and vertical transmission, we tested their potential participation in regulating the DEGs. The miRNA-mRNA interaction network, including the DEGs and the royal- and worker-jelly enriched miRNA populations, revealed a subset of miRNAs potentially involved in regulating the expression of DEGs. The interaction of miR-34, miR-210, and miR-317 with Takeout, Neurotrophin-1, Forked, and Masquerade genes was experimentally confirmed using a luciferase reporter system. Taken together, our results reconstruct the regulatory network that governs the development of the early brain diphenism in honey bees. 相似文献
95.
Vincent A. Stadelmann Jean Hocké Jensen Verhelle Vincent Forster Francesco Merlini Alexandre Terrier 《Computer methods in biomechanics and biomedical engineering》2013,16(1):95-100
A combined experimental/numerical study was performed to calculate the 3D octahedral shear strain map in a mouse tibia loaded axially. This study is motivated by the fact that the bone remodelling analysis, in this in vivo mouse model should be performed at the zone of highest mechanical stimulus to maximise the measured effects. Accordingly, it is proposed that quantification of bone remodelling should be performed at the tibial crest and at the distal diaphysis. The numerical model could also be used to furnish a more subtle analysis as a precise correlation between local strain and local biological response can be obtained with the experimentally validated numerical model. 相似文献
96.
Alexandre Terrier Marjan Sedighi-Gilani Alireza Roshan Ghias Line Aschwanden Dominique P. Pioletti 《Computer methods in biomechanics and biomedical engineering》2013,16(3):333-339
Tibial bone defect is a critical problem for revision knee arthroplasty. Instead of using metallic spacer or cement, biodegradable scaffolds could be an alternative solution. A numerical model of a revision knee arthroplasty was thus developed to estimate the mechanical resistance of the scaffold in this demanding situation. The tibia, scaffold, and prosthesis were represented by simplified parameterised geometries. The maximal gait cycle force was applied asymmetrically to simulate a critical loading. Several parameters were analysed: 1) inter-individual variability, 2) cortical bone stiffness, 3) cortical bone thickness, 4) prosthesis fixation quality, and 5) scaffold thickness. The calculated scaffold strain was compared to its experimental ultimate strain. Among the tested parameters, failure was only predicted with scaffold thickness below 5 mm. This study suggests that biodegradable bone scaffolds could be used to fill bone defects in revision knee arthroplasty, but scaffold size seems to be the limiting factor. 相似文献
97.
J. A. C. Alexandre B. Roy D. Topalis C. Périgaud D. Deville-Bonne 《Nucleosides, nucleotides & nucleic acids》2013,32(10-12):1375-1379
Over recent years, there has been a renewed interest in the development of l-nucleosides as safe and efficacious drugs for the treatment of viral infections. Biological activity of these compounds requires phosphorylation to their triphosphate form, involving nucleoside monophosphate kinases in the second step. In order to characterize the activation pathway of l-nucleosides of the pyrimidine series, we studied the enantio-selectivity of human uridylate-cytidylate and thymidylate kinases. The results showed that these enzymes are only weakly enantio-selective and are thus probably involved in the activation of l-nucleosides in vivo. An activation pathway for telbivudine (l-dT) was therefore proposed. 相似文献
98.
99.
Fernanda R. da Silva Bernardo Erdtmann Tiago Dalpiaz Emilene Nunes Alexandre Ferraz Tales L.C. Martins Johny F. Dias Darlan P. da Rosa Marilene Porawskie Silvia Bona Juliana da Silva 《Genetics and molecular biology》2013,36(2):269-275
Tobacco farmers are routinely exposed to complex mixtures of inorganic and organic chemicals present in tobacco leaves. In this study, we examined the genotoxicity of tobacco leaves in the snail Helix aspersa as a measure of the risk to human health. DNA damage was evaluated using the micronucleus test and the Comet assay and the concentration of cytochrome P450 enzymes was estimated. Two groups of snails were studied: one fed on tobacco leaves and one fed on lettuce (Lactuca sativa L) leaves (control group). All of the snails received leaves (tobacco and lettuce leaves were the only food provided) and water ad libitum. Hemolymph cells were collected after 0, 24, 48 and 72 h. The Comet assay and micronucleus test showed that exposure to tobacco leaves for different periods of time caused significant DNA damage. Inhibition of cytochrome P450 enzymes occurred only in the tobacco group. Chemical analysis indicated the presence of the alkaloid nicotine, coumarins, saponins, flavonoids and various metals. These results show that tobacco leaves are genotoxic in H. aspersa and inhibit cytochrome P450 activity, probably through the action of the complex chemical mixture present in the plant. 相似文献
100.
José Alexandre F. Diniz-Filho Thannya N. Soares Jacqueline S. Lima Ricardo Dobrovolski Victor Lemes Landeiro Mariana Pires de Campos Telles Thiago F. Rangel Luis Mauricio Bini 《Genetics and molecular biology》2013,36(4):475-485
The comparison of genetic divergence or genetic distances, estimated by pairwise FST and related statistics, with geographical distances by Mantel test is one of the most popular approaches to evaluate spatial processes driving population structure. There have been, however, recent criticisms and discussions on the statistical performance of the Mantel test. Simultaneously, alternative frameworks for data analyses are being proposed. Here, we review the Mantel test and its variations, including Mantel correlograms and partial correlations and regressions. For illustrative purposes, we studied spatial genetic divergence among 25 populations of Dipteryx alata (“Baru”), a tree species endemic to the Cerrado, the Brazilian savannas, based on 8 microsatellite loci. We also applied alternative methods to analyze spatial patterns in this dataset, especially a multivariate generalization of Spatial Eigenfunction Analysis based on redundancy analysis. The different approaches resulted in similar estimates of the magnitude of spatial structure in the genetic data. Furthermore, the results were expected based on previous knowledge of the ecological and evolutionary processes underlying genetic variation in this species. Our review shows that a careful application and interpretation of Mantel tests, especially Mantel correlograms, can overcome some potential statistical problems and provide a simple and useful tool for multivariate analysis of spatial patterns of genetic divergence. 相似文献