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991.
For decades, lichenologists have developed numerous and varied methods to isolate lichen photobionts. Most procedures are tedious, slow, and require several months after the initial isolation to obtain clones. Furthermore, the purity of the isolated photobionts obtained by more rapid methods is not sufficient to establish phycobiont axenic cultures. We have developed a new method for isolating lichen photobionts from fruticose, foliose and crustose lichens. Basically, it involves homogenization of lichen thalli (from 15 mg to 2 g), a one-step centrifugation through Percoll ®, followed by washing with Tween 20 and sonication. With this simple and rapid method (which takes less than 2 h), photobiont cells are obtained in sufficient quantity and purity to obtain dozens of axenic algal cultures. 相似文献
992.
de Carvalho KI Fernandes HB Machado FD Oliveira IS Oliveira FA Nunes PH Lima JT Almeida JR Oliveira RC 《Biological research》2010,43(4):459-465
This study evaluated the antiulcer activity of an ethanolic extract of Encholirium spectabile (ES-EtOH) by using different standard experimental models of induced acute gastric ulceration. ES-EtOH (100 mg/kg p.o) protected the gastric mucosa against ulceration that was induced by absolute ethanol (53%), ethanol/HCl (75%), ibuprofen (52 %) and ischemia/reperfusion (43 %). It also restored catalase activity and non-protein sulfhydryl group concentration in the gastric wall of mice that had been treated with ethanol. The pre-treatment of mice with N-nitro-L-arginine (70 mg/kg i.p.) abolished the protective activity of ES-EtOH, which indicates that prostaglandins, antioxidant compounds and nitric oxide synthase activity are involved in the gastroprotective activity of the extract. 相似文献
993.
994.
Cleiton Diniz Barros Angélica Amorim Amato Tiago Bento de Oliveira Karime Bicas Rocha Iannini Anekécia Lauro da Silva Teresinha Gonçalves da Silva Elisa Soares Leite Marcelo Zaldini Hernandes Maria do Carmo Alves de Lima Suely Lins Galdino Francisco de Assis Rocha Neves Ivan da Rocha Pitta 《Bioorganic & medicinal chemistry》2010,18(11):3805-3811
Eight new 5-arylidene-3-benzyl-thiazolidine-2,4-diones with halide groups on their benzyl rings were synthesized and assayed in vivo to investigate their anti-inflammatory activities. These compounds showed considerable biological efficacy when compared to rosiglitazone, a potent and well-known agonist of PPARγ, which was used as a reference drug. This suggests that the substituted 5-arylidene and 3-benzylidene groups play important roles in the anti-inflammatory properties of this class of compounds. Docking studies with these compounds indicated that they exhibit specific interactions with key residues located in the site of the PPARγ structure, which corroborates the hypothesis that these molecules are potential ligands of PPARγ. In addition, competition binding assays showed that four of these compounds bound directly to the ligand-binding domain of PPARγ, with reduced affinity when compared to rosiglitazone. An important trend was observed between the docking scores and the anti-inflammatory activities of this set of molecules. The analysis of the docking results, which takes into account the hydrophilic and hydrophobic interactions between the ligands and the target, explained why the 3-(2-bromo-benzyl)-5-(4-methanesulfonyl-benzylidene)-thiazolidine-2,4-dione compound had the best activity and the best docking score. Almost all of the stronger hydrophilic interactions occurred between the substituted 5-arylidene group of this compound and the residues of the binding site. 相似文献
995.
Ricardo Sánchez David Pantoja-Uceda Jesús Prieto Tammo Diercks María J. Marcaida Guillermo Montoya Ramón Campos-Olivas Francisco J. Blanco 《The Journal of biological chemistry》2010,285(29):22196-22201
Gadd45α is a nuclear protein encoded by a DNA damage-inducible gene. Through its interactions with other proteins, Gadd45α participates in the regulation of DNA repair, cell cycle, cell proliferation, and apoptosis. The NMR structure of human Gadd45α has been determined and shows an α/β fold with two long disordered and flexible regions at the N terminus and one of the loops. Human Gadd45α is predominantly monomeric in solution but exists in equilibrium with dimers and other oligomers whose population increases with protein concentration. NMR analysis shows that Aurora A interacts through its N-terminal domain with a region of human Gadd45α encompassing the site of dimerization, suggesting that the oligomerization of Gadd45α could be a regulatory mechanism to modulate its interactions with Aurora A, and possibly with other proteins too. However, Gadd45α appears to interact only weakly with PCNA through its flexible loop, in contrast with previous and contradictory reports. 相似文献
996.
997.
Javier Delgado-Lista Francisco Perez-Jimenez Juan Ruano Pablo Perez-Martinez Francisco Fuentes Juan Criado-Garcia Laurence D Parnell Antonio Garcia-Rios Jose M Ordovas Jose Lopez-Miranda 《Journal of lipid research》2010,51(1):63-73
The APOA1/C3/A4/A5 gene cluster encodes important regulators of fasting lipids, but the majority of lipid metabolism takes place in the postprandial state and knowledge about gene regulation in this state is scarce. With the aim of characterizing possible regulators of lipid metabolism, we studied the effects of nine single nucleotide polymorphisms (SNPs) during postprandial lipid metabolism. Eighty-eight healthy young men were genotyped for APOA1 -2630 (rs613808), APOA1 -2803 (rs2727784), APOA1 -3012 (rs11216158), APOC3 -640 (rs2542052), APOC3 -2886 (rs2542051), APOC3 G34G (rs4520), APOA4 N147S (rs5104), APOA4 T29T (rs5092), and A4A5_inter (rs1263177) and were fed a saturated fatty acid-rich meal (1g fat/kg of weight with 60% fat, 15% protein and 25% carbohydrate). Serial blood samples were extracted for 11 h after the meal. Total cholesterol and fractions [HDL-cholesterol, LDL-cholesterol, trifacylglycerols (TGs) in plasma, TG-rich lipoproteins (TRLs) (large TRLs and small TRLs), apolipoprotein A-I and apolipoprotein B] were determined. APOA1 -2803 homozygotes for the minor allele and A4A5_inter carriers showed a limited degree of postprandial lipemia. Carriers of the rare alleles of APOA4 N147S and APOA4 T29T had lower APOA1 plasma concentration during this state. APOC3 -640 was associated with altered TG kinetics but not its magnitude. We have identified new associations between SNPs in the APOA1/C3/A4/A5 gene cluster and altered postprandial lipid metabolism. 相似文献
998.
Mónica Fernández Ma. ángeles Rojo Patricia Casanueva Silvia Carrión Ma. ángeles Hernández Francisco Campos 《Journal of Ornithology》2010,151(1):27-32
Apicomplexan blood parasites (genera Haemoproteus, Plasmodium and Leucocytozoon) prevalence in two related species (Reed Warbler Acrocephalus scirpaceus and Sedge Warbler A. schoenobaenus) was studied in 2006 at the Natural Reserve of Castronu?o-Vega del Duero, Western Spain, a stopover area during the autumn
migration. A fragment of the mitochondrial cytochrome b gene of the parasites was amplified, using a nested PCR assay, from avian blood samples. High prevalence of malaria parasites
was found in both species, 84.6% in Reed Warbler and 71.8% in Sedge Warbler, and the degree of infection reach 100% of the
population that breed at the Reserve, suggesting good conditions for the development of dipteran vectors in this area. By
sequencing 464 nucleotides of the obtained fragments, we found four different mitochondrial haplotypes of Haemoproteus or Plasmodium in the two species analysed. Leucocytozoon infection was not detected, in contrast to the high prevalence of this parasite in other avian species in Spain, probably
because the water course studied is not an adequate habitat for its vectors. 相似文献
999.
Carla V. Galmozzi Lorena Saelices Francisco J. Florencio M. Isabel Muro-Pastor 《Journal of bacteriology》2010,192(18):4701-4711
1000.
Raphael Ligeiro Marcelo S. Moretti José Francisco GonçalvesJr. Marcos Callisto 《Hydrobiologia》2010,654(1):125-136
The objective of this study was to evaluate the influences of detritus from the leaves of different species, and of exposure
time on invertebrate colonization of leaves in a shaded Cerrado stream. We hypothesized that the exposure time is the main
factor that influences the colonization of leaves by invertebrates. We used leaves of five tree species native to the Brazilian
Cerrado: Protium heptaphyllum and Protium brasiliense (Burseraceae), Ocotea sp. (Lauraceae), Myrcia guyanensis (Myrtaceae), and Miconia chartacea (Melastomataceae), which are characterized by their toughness and low-nutritional quality. Litter bags, each containing leaves
from one species, were placed in a headwater stream and removed after 7, 15, 30, 60, 90, and 120 days. The dominant taxon
was Chironomidae, which comprised ca. 52% of all organisms and ca. 20% of the total biomass. The taxonomic richness of colonizing
organisms did not vary among the leaf species. However, the density and biomass of the associated organisms varied differently
among the kinds of detritus during the course of the incubation. The collector-gatherers and shredders reached higher densities
in the detritus that decomposed more rapidly (Ocotea sp. and M. guyanensis), principally in the more advanced stages of colonization. The collector-filterers reached higher densities in the detritus
that decomposed more slowly (P. heptaphyllum, P. brasiliense, and M. chartacea), principally in the initial stages of incubation. A cluster analysis divided the detritus samples of different leaf species
according to the exposure time (initial phase: up to 7 days; intermediate phase: 7–30 days; advanced phase: 30–120 days),
suggesting some succession in invertebrate colonization, with differences in taxon composition (indicator taxa analysis).
These results suggest that regardless of the leaf-detritus species, exposure time was the main factor that influenced the
colonization process of aquatic invertebrates. 相似文献