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991.
John Lennon Silva-Cunha Israel Leal Cavalcante Caio Csar da Silva Barros Fernanda Arago Felix Luan Borges Venturi Larissa Santos Amaral Rolim Csar Luis Porpino Santos da Silva-Júnior Emanuel Mendes Sousa ricka Janine Dantas da Silveira Michelle Agostini Mrio Jos Romanach Oslei Paes de Almeida Sílvia Ferreira de Sousa Bruno Augusto Benevenuto de Andrade 《Medicina oral, patología oral y cirugía bucal》2022,27(1):e35
992.
Ericles Otvio Santos Pedro Lima Emmerich Oliveira Thaís Pereira de Mello Andr Luis Souza dos Santos Carlos Nelson Elias Sung-Hwan Choi Amanda Cunha Regal de Castro 《Materials》2022,15(2)
The wide application of additive manufacturing in dentistry implies the further investigation into oral micro-organism adhesion and biofilm formation on vat-photopolymerization (VP) dental resins. The surface characteristics and microbiological analysis of a VP dental resin, printed at resolutions of 50 μm (EG-50) and 100 μm (EG-100), were evaluated against an auto-polymerizing acrylic resin (CG). Samples were evaluated using a scanning electron microscope, a scanning white-light interferometer, and analyzed for Candida albicans (CA) and Streptococcus mutans (SM) biofilm, as well as antifungal and antimicrobial activity. EG-50 and EG-100 exhibited more irregular surfaces and statistically higher mean (Ra) and root-mean-square (rms) roughness (EG-50-Ra: 2.96 ± 0.32 µm; rms: 4.05 ± 0.43 µm/EG-100-Ra: 3.76 ± 0.58 µm; rms: 4.79 ± 0.74 µm) compared to the CG (Ra: 0.52 ± 0.36 µm; rms: 0.84 ± 0.54 µm) (p < 0.05). The biomass and extracellular matrix production by CA and SM and the metabolic activity of SM were significantly decreased in EG-50 and EG-100 compared to CG (p < 0.05). CA and SM growth was inhibited by the pure unpolymerized VP resin (48 h). EG-50 and EG-100 recorded a greater irregularity, higher surface roughness, and decreased CA and SM biofilm formation over the CG. 相似文献
993.
Betina Santos Tomaz Gabriela Carvalho Gomes Juliana Arcanjo Lino David Guabiraba Abitbol de Menezes Jorge Barbosa Soares Vasco Furtado Luiz Soares Júnior Maria do Socorro Quintino Farias Debora Lilian Nascimento Lima Eanes Delgado Barros Pereira Marcelo Alcantara Holanda 《Jornal brasileiro de pneumologia》2022,48(1)
994.
995.
Manda Sathish Akash P. Sakla Fabiane M. Nachtigall Leonardo S. Santos Nagula Shankaraiah 《RSC advances》2021,11(27):16537
Multi-reactive centered reagents are beneficial in chemical synthesis due to their advantage of minimal material utilization and formation of less by-products. Trichloroisocyanuric acid (TCCA), a reagent with three reactive centers, was employed in the synthesis of spirooxindoles through the oxidative rearrangement of various N-protected tetrahydro-β-carbolines. In this protocol, low equivalents of TCCA were required to access spirooxindoles (up to 99% yield) with a wide substrate scope. Furthermore, the applicability and robustness of this protocol were proven for the gram-scale total synthesis of natural alkaloids such as (±)-coerulescine (1) and (±)-horsfiline (2) in excellent yields.Three-reactive centered reagent (TCCA) mediated construction of spirooxindoles through an oxidative rearrangement of various N-protected tetrahydro-β-carbolines and total synthesis of natural alkaloids (±)-coerulescine and (±)-horsfiline. 相似文献
996.
Ananda da Silva Antonio Davi Santos Oliveira Gustavo Ramalho Cardoso dos Santos Henrique Marcelo Gualberto Pereira Larissa Silveira Moreira Wiedemann Valdir Florêncio da Veiga-Junior 《RSC advances》2021,11(40):25096
Untargeted metabolomics is a powerful tool in chemical fingerprinting. It can be applied in phytochemistry to aid species identification, systematic studies and quality control of bioproducts. This approach aims to produce as much chemical information as possible, without focusing on any specific chemical class, thus, requiring extensive chemometric effort. This study aimed to evaluate the feasibly of an untargeted metabolomics method in phytochemistry by a study case of the Copaifera genus (Fabaceae). This genus contains significant medicinal species used worldwidely. Copaifera exploitation issues include a lack of chemical data, ambiguous species identification methods and absence of quality control for its bioproducts. Different organs of five Copaifera species were analysed by UHPLC-HRMS/MS, GNPS platform and chemometric tools. Untargeted metabolomics enabled the identification of 19 chemical markers and 29 metabolites, distinguishing each sample by species, plant organs, and biome type. Chemical markers were classified as flavonoids, terpenoids and condensed tannins. The applied method provided reliable information about species chemodiversity using fast workflow with little sampling size. The untargeted approach by UHPLC-HRMS/MS proved to be a promising tool for species identification, pharmacological prospecting and in the future for the quality control of extracts used in the manufacture of bioproducts.UHPLC-HRMS/MS untargeted metabolomics enabled distinction of Copaifera extracts by species, vegetative parts, and biome of origin based on 19 chemical markers. 相似文献
997.
Maicon Oliveira Miranda Wesley Eullio Cabral Cavalcanti Felipe Fernandes Barbosa Jos Antonio de Sousa Francisco Ivan da Silva Sibele B. C. Pergher Tiago Pinheiro Braga 《RSC advances》2021,11(44):27720
The present work studied ibuprofen degradation using titanium dioxide as a photocatalyst. Mechanistic aspects were presented and the preferred attack sites by the OH˙ radical on the ibuprofen molecule were detailed, based on experimental and simple theoretical-computational results. Although some previous studies show mechanistic proposals, some aspects still need to be investigated, such as the participation of 4-isobutylacetophenone in the ibuprofen degradation and the preferred regions of attack by OH˙ radicals. The photodegradation was satisfactory using 0.03 g of TiO2 and pH = 5.0, reaching 100% decontamination in 5 min. The zeta potential curve showed the regions of attraction and repulsion between TiO2 and ibuprofen, depending on the pH range and charge of the species, influencing the amount of by-products formed. Different by-products have been identified by GC-MS, such as 4-isobutylacetophenone. Ibuprofen conversion to 4-isobutylacetophenone takes place through decarboxylation reaction followed by oxidation. The proposed mechanism indicates that the degradation of ibuprofen undergoes a series of elementary reactions in solution and on the surface. Three different radicals (OH˙, O2−˙ and OOH˙) are produced in the reaction sequence and contribute strongly to the oxidation and mineralization of ibuprofen and by-products, but the hydroxyl radical has a greater oxidation capacity. The simple study using the DFT approach demonstrated that the OH˙ radical attacks preferentially in the region of the ibuprofen molecule with high electronic density, which is located close to the aromatic ring (C C bond). The presence of the OH˙ radical was confirmed through a model reaction using salicylic acid as a probe molecule.The degradation of ibuprofen undergoes a series of elementary reactions, generating different radicals which attack preferentially in the region of the ibuprofen with high electron density. 相似文献
998.
Daniela S. Camilo Fernando Pradella Maria Fernanda Paulino Emilio C. E. Baracat Sofia H. Marini Gil Guerra Elizabeth J. Pavin Candida Parisi Ana Leda F. Longhini Silvia B. Marques Edilaine G. Guariento Sofia R. Lieber Carlos Fernando Macedo Letícia Gama e Silva Alessandro S. Farias Leonilda M. B. Santos Walkyria M. G. Volpini 《Pediatric diabetes》2020,21(4):606-614
999.