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991.
992.
Luciano Elias Da Cruz Perez Ana Lucia Machado Sebastião Vicente Canevarolo Carlos Eduardo Vergani Eunice Teresinha Giampaolo Ana Cláudia Pavarina 《Gerodontology》2010,27(1):62-69
doi:10.1111/j.1741‐2358.2009.00292.x Effect of reline material and denture base surface treatment on the impact strength of a denture base acrylic resin Objective: In this study, the effect of relining and surface treatment on the impact strength (IS) of a heat‐polymerising denture base acrylic resin (Lucitone 550‐L) was evaluated. Materials and methods: Rectangular bars of L were made (60 × 6 × 2 mm) and relined (2 mm) with the relining resins Ufi Gel Hard (UH) and Tokuso Rebase Fast (TR). Specimens relined with L and intact L, TR and UH specimens were also made (60 × 6 × 4 mm), for comparison. Before relining, the L surface was left untreated or wetted with methyl methacrylate monomer and/or the bonding agents (BA) supplied by manufacturers of the reline resins. V‐notches were machined at the midpoint of the length of all specimens. The notches were made either across the width (Nw) or across the thickness of the specimens (Nth). The Charpy impact test was performed using a 0.5‐J pendulum, which had been specially designed and constructed. Data were analysed separately for each notch position using one‐way analysis of variance and Tukey honestly significant difference post‐hoc test (p = 0.05). Results: The IS of L was similar to that of L/L. For the Nw notch, treating the denture base L with TR BA and relining with TR reline material produced the highest IS. Conclusion: The IS of specimens made from heat polymerising acrylic resin Lucitone 550 was increased after relining using the hard chairside reline resin TR with its proprietary BA. 相似文献
993.
Ian R. Ellis Sarah J. Jones Yvonne Lindsay Go Ohe Ana M. Schor Seth L. Schor Nick R. Leslie 《Cellular signalling》2010,22(11):1655-1659
The protein kinase AKT is activated strongly by many motogenic growth factors, yet has recently been shown capable of inhibiting migration in several cell types. Here we report that treatment with Migration Stimulating Factor (MSF), a truncated form of fibronectin that promotes the migration of many cell types, inhibits AKT activity in human fibroblasts and endothelial cells. In fibroblasts, treatment with either MSF or the AKT inhibitor, Akti-1/2, stimulated migration into 3D collagen gels to a similar extent and the effects of Akti-1/2 on migration could be blocked by the expression of an inhibitor-resistant mutant, AKT1 W80A. These data indicate that MSF promotes fibroblast migration, at least in part, by inhibiting the activity of AKT. 相似文献
994.
In floating soils, organic matter accumulation is the result of the imbalance between decomposition rate and macrophytes’
production, and it can limit nutrient availability. In this study, we determined the percentage of litter that is added to
the floating soil in one year and the nitrogen dynamics of Rhynchospora asperula (Nees) Steud (Cyperaceae), an abundant species in Esteros del Iberá, a South American wetland with extended areas of floating
soils. According to the decomposition rate determined (k = 0.0032 day−1), the annual percentage of mass lost was 69%. Conditions of the floating soil were simulated in a 146-day field experiment.
The results show that the decomposition rate was higher when the litter was in water contact, and the mass loss in the field
sampling at the beginning of the decomposition was similar to that of the treatments that simulated this condition. The nitrogen
concentration in the aboveground biomass was almost constant, and the results indicate that there was translocation from the
senescent leaves, but not a preferential nitrogen translocation from the rhizomes and roots. During summer the maximum biomass
and the low nitrogen concentration in the floating soil coincide, but the nitrogen intake by the aboveground biomass was only
4% of the total nitrogen content of the floating soil. Nitrogen concentration in the litter increased and, though immobilization
cannot be ruled out, there was net mineralization. The nitrogen mineralized in the first decomposition year was 30% of the
nitrogen added to aboveground biomass during the study period. 相似文献
995.
Wilhelm M. Malloni Silvia De Sanctis Ana M. Tomé Elmar W. Lang Claudia E. Munte Klaus Peter Neidig Hans Robert Kalbitzer 《Journal of biomolecular NMR》2010,47(2):101-111
Strong solvent signals lead to a disappearance of weak protein signals close to the solvent resonance frequency and to base
plane variations all over the spectrum. AUREMOL-SSA provides an automated approach for solvent artifact removal from multidimensional
NMR protein spectra. Its core algorithm is based on singular spectrum analysis (SSA) in the time domain and is combined with
an automated base plane correction in the frequency domain. The performance of the method has been tested on synthetic and
experimental spectra including two-dimensional NOESY and TOCSY spectra and a three-dimensional 1H,13C-HCCH-TOCSY spectrum. It can also be applied to frequency domain spectra since an optional inverse Fourier transformation
is included in the algorithm. 相似文献
996.
Stephan Nielen Lucas M. Almeida Vera T. C. Carneiro Ana Claudia G. Araujo 《Sexual plant reproduction》2010,23(1):45-51
Brachiaria (Trin.) Griseb belongs to the family Poaceae, and within the genus, apomixis or sexuality is present in different accessions
of the same species. The majority of Brachiaria species are polyploid and apomictic, making strategies for crop improvement by breeding very intricate. In spite of the high
frequency of apomictic polyploids, the relationship of polyploidy and hybridization with apomixis in Brachiaria is still unclear. Further analysis requires detailed knowledge regarding the genomic composition of the polyploids. The present
work introduces the use of fluorescent in situ hybridization (FISH) into cytogenetic analysis of Brachiaria. Physical mapping of heterologous rDNA sequences, associated with conventional karyotyping of the B. brizantha diploid sexual (BRA 002747) and the tetraploid apomictic (BRA000591) accessions, provided evidence of the latter being of
allopolyploid origin. Based on our results and on previous knowledge on apomixis in B. brizantha, we suggest that the origin of apomixis was probably a consequence of hybridization. 相似文献
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1000.
Sabrina Pinto Salamoni Michele B. Mann Fabrício S. Campos Ana Claudia Franco José C. Germani Sueli T. Van Der Sand 《World journal of microbiology & biotechnology》2010,26(10):1847-1856
The aim of this study was to screen Streptomycetes isolates with antimicrobial and antiviral activity, in a search for new metabolites. The isolates were obtained from a composting process, and identified based on morphological characteristics and molecular biological methods. The antimicrobial activity was determined using the double-layer agar method against 53 test organisms (bacteria, yeasts, and filamentous fungi). All isolates were grown in submerged culture, in mineral salts-starch-casein (SC) broth and ISP2 media, and the filtrate cultures were used in the assays for antibacterial and antiviral activity. Bovine Herpes virus (BoHV-I) was used for the antiviral activity. The morphological and molecular characteristics confirmed that all 25 isolates belonged to the genus Streptomyces. In the assay for antimicrobial activity, 80% of the Streptomyces isolates were able to inhibit at least one of the test organisms. Of these, 80% were active against bacteria and 45% against fungi. Eight of the isolates showed a broad spectrum of inhibitory activity; of these, the isolate Streptomyces spp. 1S was able to inhibit 46 of the test organisms, and, most importantly, the 16 Gram-negative strains were inhibited. Of the 25 isolates, 44.4% of the isolates were able to grow and produce bioactive metabolites when grown in submerged culture. Four extracts showed a cytopathic effect in 10 CCID50 MDBK cell, even though no viricidal effect was observed. The results obtained with these isolates indicated good biotechnological potential of these Streptomyces strains. 相似文献