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201.
First description of blaNDM-1, blaOXA-48, blaOXA-181 producing Enterobacteriaceae strains in Romania
Edit Székely Ivelina Damjanova Laura Jánvári Krisztina E. Vas Szabolcs Molnár Doina V. Bilca Lilla K. Lőrinczi Ákos Tóth 《International journal of medical microbiology : IJMM》2013,303(8):697-700
We report the first isolation and characterization of several Enterobacteriaceae strains harboring blaNDM-1, blaOXA-48 and/or blaOXA-181 genes in a Romanian emergency teaching hospital. Between January 2010 and September 2012 nine carbapenemase-producing Enterobacteriaceae strains were identified. The blaNDM-1 gene was present in two Enterobacter cloacae strains, an Escherichia coli and two Klebsiella pneumoniae strains. One of these K. pneumoniae strains also harbored the blaOXA-181 gene. Three other K. pneumoniae strains and one Serratia marcescens carried blaOXA-48. 相似文献
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《Saudi Dental Journal》2021,33(7):533-537
Context.Proteins in the saliva are one of the defense mechanism factors that can protect the oral cavity from disease. However, smoking might affect the properties of saliva.AimTo determine the differences in salivary protein profiles and total concentrations in smokers and non-smokers and their correlation with dental caries severity as indicated by the Decayed, Missing, Filled-Teeth (DMF-T) scores.Methods and materialThis cross-sectional study included 25 smokers and 25 non-smokers. The DMF-T scores were recorded. The total salivary protein was measured by the Bradford method, and the profile proteins were determined by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE).ResultsThe average of salivary protein concentration in smokers was lower than that in non-smokers (551.486 µg/mL versus 765.361 µg/mL), but the difference was not statistically significant (P > 0.05). Further correlation analyses showed a negative correlation between the concentration of proteins based on the extent of smoking. A weak negative correlation was found between protein concentration and DMF-T scores (r = −0.239). Dominant salivary protein bands of 11.6 kDa and 54.5 kDa were found in smokers and 27 kDa, 60 kDa, and 94.5 kDa were found in non-smokers.ConclusionDifferent protein bands appeared in smokers and non-smokers. There was a weak correlation between protein concentration, DMF-T scores, and the extent of smoking. 相似文献
205.
Anna Veverkov Dalibor Preisler Mariia Zimina Tereza Koutov Petr Harcuba Milo Jane
ek Josef Strský 《Materials》2021,14(2)
Low-alloyed zirconium alloys are widely used in nuclear applications due to their low neutron absorption cross-section. These alloys, however, suffer from limited strength. Well-established guidelines for the development of Ti alloys were applied to design new two-phase ternary Zr alloys with improved mechanical properties. Zr-4Sn-4Nb and Zr-8Sn-4Nb alloys have been manufactured by vacuum arc melting, thermo-mechanically processed by annealing, forging, and aging to various microstructural conditions and thoroughly characterized. Detailed Scanning electron microscopy (SEM) analysis showed that the microstructural response of the alloys is rather similar to alpha + beta Ti alloys. Duplex microstructure containing primary alpha phase particles surrounded by lamellar alpha + beta microstructure can be achieved by thermal processing. Mechanical properties strongly depend on the previous treatment. Ultimate tensile strength exceeding 700 MPa was achieved exceeding the strength of commercial Zr alloys for nuclear applications by more than 50%. Such an improvement in strength more than compensates for the increased neutron absorption cross-section. This study aims to exploit the potential of alpha + beta Zr alloys for nuclear applications. 相似文献
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Mineral trioxide aggregate enriched with iron disulfide nanostructures: an evaluation of their physical and biological properties
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Liliana Argueta‐Figueroa José J. Delgado‐García René García‐Contreras Omar Martínez‐Alvarez José Santos‐Cruz Carlos Oliva‐Martínez Laura S. Acosta‐Torres Javier de la Fuente‐Hernández Ma C. Arenas‐Arrocena 《European journal of oral sciences》2018,126(3):234-243
The purpose of this study was to characterize mineral trioxide aggregates (MTA) enriched with iron disulfide (FeS2) nanostructures at different concentrations, and to investigate their storage modulus, radiopacity, setting time, pH, cytotoxicity, and antimicrobial activity. Iron disulfide nanostructures [with particle size of 0.357 ± 0.156 μm (mean ± SD)] at weight ratios of 0.2, 0.4, 0.6, 0.8, and 1.0 wt% were added to white MTA (wMTA). The radiopacity, rheological properties, setting time, and pH, as well as the cytotoxicity (assessed using the MTT assay) and antibacterial activity (assessed using the broth microdilution test) were determined for MTA/FeS2 nanostructures. The nanostructures did not modify the radiopacity values of wMTA (~6 mm of aluminium); however, they reduced the setting time from 18.2 ± 3.20 min to 13.7 ± 1.8 min, and the storage modulus was indicative of a good stiffness. Whereas the wMTA/FeS2 nanostructures did not induce cytotoxicity when in contact with human pulp cells (HPCs) and human gingival fibroblasts (HGFs), they showed bacteriostatic activity against Staphylococcus aureus, Escherichia coli, and Enterococcus faecalis. Adding FeS2 nanostructures to MTA might be an option for improving the root canal sealing and antibacterial effects of wMTA in endodontic treatments. 相似文献
208.
L. Yang Y. Huang F. Feyerabend R. Willumeit C. Mendis K.U. Kainer N. Hort 《Acta biomaterialia》2013,9(10):8499-8508
In previous investigations, a Mg–10Dy (wt.%) alloy with a good combination of corrosion resistance and cytocompatibility showed great potential for use as a biodegradable implant material. However, the mechanical properties of Mg–10Dy alloy are not satisfactory. In order to allow the tailoring of mechanical properties required for various medical applications, four Mg–10(Dy + Gd)–0.2Zr (wt.%) alloys were investigated with respect to microstructure, mechanical and corrosion properties. With the increase in Gd content, the number of second-phase particles increased in the as-cast alloys, and the age-hardening response increased at 200 °C. The yield strength increased, while the ductility reduced, especially for peak-aged alloys with the addition of Gd. Additionally, with increasing Gd content, the corrosion rate increased in the as-cast condition owing to the galvanic effect, but all the alloys had a similar corrosion rate (~0.5 mm year?1) in solution-treated and aged condition. 相似文献
209.
Antonio Greco Mariaenrica Frigione Alfonso Maffezzoli Alessandro Marseglia Alessandra Passaro 《Materials》2014,7(7):5385-5402
This work is aimed to present an innovative technology for the reinforcement of beams for urban furniture, produced by in-mold extrusion of plastics from solid urban waste. This material, which is usually referred to as “recycled plastic lumber”, is characterized by very poor mechanical properties, which results in high deflections under flexural loads, particularly under creep conditions. The Prowaste project, founded by the EACI (European Agency for Competitiveness and Innovation) in the framework of the Eco-Innovation measure, was finalized to develop an innovative technology for selective reinforcement of recycled plastic lumber. Selective reinforcement was carried out by the addition of pultruded glass rods in specific positions with respect to the cross section of the beam, which allowed optimizing the reinforcing efficiency. The reinforcement of the plastic lumber beams with pultruded rods was tested at industrial scale plant, at Solteco SL (Alfaro, Spain). The beams obtained, characterized by low cost and weight, were commercialized by the Spanish company. The present paper presents the most relevant results of the Prowaste project. Initially, an evaluation of the different materials candidates for the reinforcement of recycled plastic lumber is presented. Plastic lumber beams produced in the industrial plant were characterized in terms of flexural properties. The results obtained are interpreted by means of beam theory, which allows for extrapolation of the characteristic features of beams produced by different reinforcing elements. Finally, a theoretical comparison with other approaches which can be used for the reinforcement of plastic lumber is presented, highlighting that, among others, the Prowaste concept maximizes the stiffening efficiency, allowing to significantly reduce the weight of the components. 相似文献
210.