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951.
952.
Silvia Affò Daniel Rodrigo-Torres Delia Blaya Oriol Morales-Ibanez Mar Coll Cristina Millán José Altamirano Vicente Arroyo Joan Caballería Ramón Bataller Pere Ginès Pau Sancho-Bru 《PloS one》2015,10(12)
Chronic liver diseases are characterized by a sustained inflammatory response in which chemokines and chemokine-receptors orchestrate inflammatory cell recruitment. In this study we investigated the role of the chemokine receptor CCR6 in acute and chronic liver injury. In the absence of liver injury Ccr6
-/- mice presented a higher number of hepatic macrophages and increased expression of pro-inflammatory cytokines and M1 markers Tnf-α, Il6 and Mcp1. Inflammation and cell recruitment were increased after carbon tetrachloride-induced acute liver injury in Ccr6
-/- mice. Moreover, chronic liver injury by carbon tetrachloride in Ccr6
-/- mice was associated with enhanced inflammation and fibrosis, altered macrophage recruitment, enhanced CD4+ cells and a reduction in Th17 (CD4+IL17+) and mature dendritic (MHCII+CD11c+) cells recruitment. Clodronate depletion of macrophages in Ccr6
-/- mice resulted in a reduction of hepatic pro-inflammatory and pro-fibrogenic markers in the absence and after liver injury. Finally, increased CCR6 hepatic expression in patients with alcoholic hepatitis was found to correlate with liver expression of CCL20 and severity of liver disease. In conclusion, CCR6 deficiency affects hepatic inflammatory cell recruitment resulting in the promotion of hepatic inflammation and fibrosis. 相似文献
953.
Genetic variants modify the effect of age on APOE methylation in the Genetics of Lipid Lowering Drugs and Diet Network study 下载免费PDF全文
Yiyi Ma Caren E. Smith Chao‐Qiang Lai Marguerite R. Irvin Laurence D. Parnell Yu‐Chi Lee Lucia Pham Stella Aslibekyan Steven A. Claas Michael Y. Tsai Ingrid B. Borecki Edmond K. Kabagambe Silvia Berciano José M. Ordovás Devin M. Absher Donna K. Arnett 《Aging cell》2015,14(1):49-59
Although apolipoprotein E (APOE) variants are associated with age-related diseases, the underlying mechanism is unknown and DNA methylation may be a potential one. With methylation data, measured by the Infinium Human Methylation 450 array, from 993 participants (age ranging from 18 to 87 years) in the Genetics of Lipid Lowering Drugs and Diet Network (GOLDN) study, and from Encyclopedia of DNA Elements (ENCODE) consortium, combined with published methylation datasets, we described the methylation pattern of 13 CpG sites within APOE locus, their correlations with gene expression across cell types, and their relationships with age, plasma lipids, and sequence variants. Based on methylation levels and the genetic regions, we categorized the 13 APOE CpG sites into three groups: Group 1 showed hypermethylation (> 50%) and were located in the promoter region, Group 2 exhibited hypomethylation (< 50%) and were located in the first two exons and introns, and Group 3 showed hypermethylation (> 50%) and were located in the exon 4. APOE methylation was negatively correlated with gene expression (minimum r = −0.66, P = 0.004). APOE methylation was significantly associated with age (minimum P = 2.06E-08) and plasma total cholesterol (minimum P = 3.53E-03). Finally, APOE methylation patterns differed across APOE ε variants (minimum P = 3.51E-05) and the promoter variant rs405509 (minimum P = 0.01), which further showed a significant interaction with age (P = 0.03). These findings suggest that methylation may be a potential mechanistic explanation for APOE functions related to aging and call for further molecular mechanistic studies. 相似文献
954.
Padiglia A Medda R Scanu T Longu S Rossi A Floris G 《Journal of Protein Chemistry》2002,21(7):435-441
A cDNA encoding for a copper containing amine oxidase has been isolated and sequenced from young leaves of Euphorbia characias, a perennial mediterranean shrub. A single long open reading frame of 2068 pb encodes a protein composed of 653 amino acids with a molecular mass of about 74 kDa. A putative 24-aminoacid signal peptide precedes the sequence of the mature protein, with characteristics of a secretion signal peptide. Alignments of Euphorbia amine oxidase cDNA nucleotide sequence with that of amine oxidase from the seedlings of the pulses lentil, pea, and chickpea reveal several conserved regions, especially in the C-terminus, with a homology 90%–97%. The near 5 region shows several insertions, deletions, and different nucleotide sequence with ca. 60% homology. The enzyme contains 1%–2% carbohydrate deduced by deglycosylation experiments. Five cysteine residues are present in the deduced aminoacid sequence with a single disulfide bridge as judged by titration with cysteine reagents. 相似文献
955.
Development of Genus/Species-Specific PCR Analysis for Identification of <Emphasis Type="Italic">Carnobacterium</Emphasis> Strains 总被引:6,自引:0,他引:6
Heterofermentative lactic acid bacteria belonging to the genus Carnobacterium are currently divided into seven different species, C. piscicola, C. mobile, C. gallinarum, C. inhibens, C. divergens, C. funditum, and C. alterfunditum. 16S rDNA-targeted PCR assay was carried out for the identification of the genus Carnobacterium. In addition, type strains of all Carnobacterium species were analyzed by 16S–23S rDNA intergenic spacer analysis in comparison with type strains of phylogenetically related
lactic acid bacteria. These methods enabled the identification and the discrimination among Carnobacterium species and the other phylogenetically related lactic acid bacteria. Likewise, analogous results were obtained by restriction
analysis of amplified 16S rDNA performed with HaeIII and HinfI as restriction enzymes.
Received: 25 July 2001 / Accepted: 19 October 2001 相似文献
956.
Lagarde A Spinelli S Qiao H Tegoni M Pelosi P Cambillau C 《The Biochemical journal》2011,437(3):423-430
Agam (Anopheles gambiae) relies on its olfactory system to target human prey, leading eventually to the injection of Plasmodium falciparum, the malaria vector. OBPs (odorant-binding proteins) are the first line of proteins involved in odorant recognition. They interact with olfactory receptors and thus constitute an interesting target for insect control. In the present study, we undertook a large-scale analysis of proteins belonging to the olfactory system of Agam with the aim of preventing insect bites by designing strong olfactory repellents. We determined the three-dimensional structures of several Agam OBPs, either alone or in complex with model compounds. In the present paper, we report the first three-dimensional structure of a member of the C-plus class of OBPs, AgamOBP47, which has a longer sequence than classical OBPs and contains six disulfide bridges. AgamOBP47 possesses a core of six α-helices and three disulfide bridges, similar to the classical OBP fold. Two extra loops and the N- and C-terminal extra segments contain two additional α-helices and are held in conformation by three disulfide bridges. They are located either side of the classical OBP core domain. The binding site of OBP47 is located between the core and the additional domains. Two crevices are observed on opposite sides of OBP47, which are joined together by a shallow channel of sufficient size to accommodate a model of the best-tested ligand. The binding sites of C-plus class OBPs therefore exhibit different characteristics, as compared with classical OBPs, which should lead to markedly diverse functional implications. 相似文献
957.
958.
959.
In a river, the flow directly affects the physical and chemical properties of its water, with further consequences for aquatic
biota. Land use practices and vegetation cover play a significant role in the water cycle. The wide-spread perception of forest
cover, in terms of hydrology is that forests may reduce water runoff: although in rare instances the contrary has been reported.
Water runoff varies seasonally and depends on the forest tree species. By no means can it be considered constant over large
expanses of area or for various rainfall patterns. In this paper, the results of a long-term hydrological survey conducted
in two experimental microbasins (operated by the Institute of Hydrology SAS, IH SAS) with different land use practices are
presented. The Rybárik microbasin (0.119 km2) is dominated by row crop production. The basin was 70% cultivated by the state farm and 30% by a private farm. The Lesny
microbasin (0.086 km2) is covered by a deciduous hornbeam regrowth forest (Carpinus betulus). The analysis revealed that the difference in the
runoff from the forest and the agricultural land increases with increasing precipitation; however, at some point (extreme
precipitations with low probability) the runoff from these basins is nearly equal. 相似文献
960.
Leoratti FM Trevelin SC Cunha FQ Rocha BC Costa PA Gravina HD Tada MS Pereira DB Golenbock DT Antonelli LR Gazzinelli RT 《PLoS neglected tropical diseases》2012,6(6):e1710