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排序方式: 共有2610条查询结果,搜索用时 15 毫秒
81.
Caroline E. Dale Jaroslav A. Hubacek Tom M. Palmer Hynek Pikhart Anne Peasey Annie Britton Pia Horvat Ruzena Kubinova Sofia Malyutina Andrzej Pajak Abdonas Tamosiunas Aparna Shankar Archana Singh‐Manoux Mikhail Voevoda Mika Kivimaki Aroon D. Hingorani Michael G. Marmot Juan P. Casas Martin Bobak 《Addiction (Abingdon, England)》2014,109(9):1462-1471
82.
Mikhail N. Khrizanforov Svetlana V. Fedorenko Asia R. Mustafina Vera V. Khrizanforova Kirill V. Kholin Irek R. Nizameev Tatyana V. Gryaznova Valeriya V. Grinenko Yulia H. Budnikova 《RSC advances》2019,9(39):22627
The present work introduces a facile synthetic route for efficient doping of [NiII(bpy)x] into silica nanoparticles with various sizes and architectures. Variation of the latter results in different concentrations of the NiII complexes at the interface of the composite nanoparticles. The UV-Vis analysis of the nanoparticles reveals changes in the inner-sphere environment of the NiII complexes when embedded into the nanoparticles, while the inner-sphere of NiII is invariant for the nanoparticles with different architecture. Comparative analysis of the electrochemically generated redox transformations of the NiII complexes embedded in the nanoparticles of various architectures reveals the latter as the main factor controlling the accessibility of NiII complexes to the redox transitions which, in turn, controls the electrochemical behavior of the nanoparticles. The work also highlights an impact of the nanoparticulate architecture in catalytic activity of the NiII complexes within the different nanoparticles in oxidative C–H fluoroalkylation of caffeine. Both low leakage and high concentration of the NiII complexes at the interface of the composite nanoparticles enables fluoroalkylated caffeine to be obtained in high yields under recycling of the nanocatalyst five times at least.The present work introduces a facile synthetic route for efficient doping of [NiII(bpy)x] into silica nanoparticles with various sizes and architectures. 相似文献
83.
Kieran F. Docherty Pardeep S. Jhund Olof Bengtsson David L. DeMets Silvio E. Inzucchi Lars Kber Mikhail N. Kosiborod Anna Maria Langkilde Felipe A. Martinez Marc S. Sabatine Mikaela Sjstrand Scott D. Solomon John J.V. McMurray 《Diabetes care》2020,43(11):2878
OBJECTIVETo determine whether the benefits of dapagliflozin in patients with heart failure and reduced ejection fraction (HFrEF) and type 2 diabetes in the Dapagliflozin And Prevention of Adverse-Outcomes in Heart Failure trial (DAPA-HF) varied by background glucose-lowering therapy (GLT).RESEARCH DESIGN AND METHODSWe examined the effect of study treatment by the use or not of GLT and by GLT classes and combinations. The primary outcome was a composite of worsening heart failure (hospitalization or urgent visit requiring intravenous therapy) or cardiovascular death.RESULTSIn the 2,139 type 2 diabetes patients, the effect of dapagliflozin on the primary outcome was consistent by GLT use or no use (hazard ratio 0.72 [95% CI 0.58–0.88] vs. 0.86 [0.60–1.23]; interaction P = 0.39) and across GLT classes.CONCLUSIONSIn DAPA-HF, dapagliflozin improved outcomes irrespective of use or no use of GLT or by GLT type used in patients with type 2 diabetes and HFrEF. 相似文献
84.
Georgii A. Illarionov Denis S. Kolchanov Oleg A. Kuchur Mikhail V. Zhukov Ekaterina Sergeeva Vladimir V. Krishtop Alexandr V. Vinogradov Maxim I. Morozov 《RSC advances》2019,9(62):35998
In this study we address a novel design of a planar memristor and investigate its biocompatibility. An experimental prototype of the proposed memristor assembly has been manufactured using a hybrid nanofabrication method, combining sputtering of electrodes, patterning the insulating trenches, and filling them with a memristive substance. To pattern the insulating trenches, we have examined two nanofabrication techniques employing either a focused ion beam or a cantilever tip of an atomic force microscope. Inkjet printing has been used to fill the trenches with the functional titania ink. The experimental prototypes have qualitatively demonstrated memristive current–voltage behavior, as well as high biocompatibility.A planar memristor was fabricated by a hybrid method combining AFM patterning and inkjet printing. 相似文献
85.
86.
Objective
The aim of this study is to confirm the theoretical colour predictions for single and double layers of dental composite materials on an opaque backing.Methods
Single and double layers of composite resins were fabricated, placed in optical contact with a grey backing and measured for spectral radiance. The spectral reflectance and colour were directly determined. Absorption and scattering coefficients as previously reported, the measured thickness of the single layers and the effective reflectance of the grey backing were utilized to theoretically predict the reflectance of the single layer using corrected Kubelka–Munk reflectance theory. For double layers the predicted effective reflectance of the single layer was used as the reflectance of the backing of the second layer and the thickness of the second layer was used to predict the reflectance of the double layer. Colour differences, using both the CIELAB and CIEDE2000 formulae, measured the discrepancy between each directly determined colour and its corresponding theoretical colour.Results
The colour difference discrepancies generally ranged around the perceptibility threshold but were consistently below the respective acceptability threshold.Conclusion
This theory can predict the colour of layers of composite resin within acceptability limits and generally also within perceptibility limits.Clinical significance
This theory could therefore be incorporated into computer-based optical measuring instruments that can automate the shade selections for layers of a more opaque first layer under a more translucent second layer for those clinical situations where an underlying background colour and a desirable final colour can be measured. 相似文献87.
Pierre H. Mangin Elizabeth E. Gardiner Warwick S. Nesbitt Steven W. Kerrigan Netanel Korin Wilbur A. Lam Mikhail A. Panteleev 《Journal of thrombosis and haemostasis》2020,18(3):748-752
Experimental videomicroscopic in vitro assays of thrombus formation based on blood perfusion are instrumental in a wide range of basic studies in thrombosis, screening for hereditary or acquired plateletrelated pathologies, and assessing the effectiveness of novel anti‐platelet therapies. Here, we discuss application of the broadly used “in vitro thrombosis model”: a frequently used assay to study the formation of 3D aggregates under flow, which involves perfusing anticoagulated whole blood over fibrillar collagen in a flow geometry of rectangular cross‐section, such as glass microcapillaries or parallel‐plate flow chambers. Major advantaged of this assay are simplicity and ability to reproduce the four main stages of platelet thrombus formation, i.e. platelet tethering, adhesion, activation and aggregation under a wide range of hemodynamic conditions. On the other hand, these devices represent, at best, simple reductive models of thrombosis. We also describe how blood flow assays can be used to study various aspects of platelet function on adhesive proteins and discuss the relevance of such flow models. Finally, we propose recommendations for standardization related to the use of this assay that cover collagen source, coating methods, micropatterning, sample composition, anticoagulation, choice of flow device, hemodynamic conditions, quantification challenges, variability, pre‐analytical conditions and other issues. 相似文献
88.
Vassiliy A. Medvedev Ilya E. Kolesnikov Pavel K. Olshin Mikhail D. Mikhailov Alina A. Manshina Daria V. Mamonova 《Materials》2022,15(7)
Optical materials doped with several lanthanides are unique in their properties and are widely used in various fields of science and technology. The study of these systems provides solutions for noncontact thermometry, bioimaging, sensing technology, and others. In this paper, we report on the demonstration of YVO4 nanoparticles doped with one, two, and three different rare earth ions (Tm3+, Er3+, and Nd3+). We discuss the morphology, structural properties, and luminescence behavior of particles. Luminescence decay kinetics reveal the energy transfer efficiency (up to 78%) for different ions under the selective excitation of individual ions. Thus, we found that the energy transition from Tm3+ is more favorable than from Er3+ while we did not observe any significant energy rearrangement in the samples under the excitation of Nd3+. The observed strong variation of REI lifetimes makes the suggested nanoparticles promising for luminescent labeling, anticounterfeiting, development of data storage systems, etc. 相似文献
89.
Marine E. Bozdaganyan Konstantin V. Shaitan Mikhail P. Kirpichnikov Olga S. Sokolova Philipp S. Orekhov 《Viruses》2022,14(2)
Currently, SARS-CoV-2 causing coronavirus disease 2019 (COVID-19) is responsible for one of the most deleterious pandemics of our time. The interaction between the ACE2 receptors at the surface of human cells and the viral Spike (S) protein triggers the infection, making the receptor-binding domain (RBD) of the SARS-CoV-2 S-protein a focal target for the neutralizing antibodies (Abs). Despite the recent progress in the development and deployment of vaccines, the emergence of novel variants of SARS-CoV-2 insensitive to Abs produced in response to the vaccine administration and/or monoclonal ones represent a potential danger. Here, we analyzed the diversity of neutralizing Ab epitopes and assessed the possible effects of single and multiple mutations in the RBD of SARS-CoV-2 S-protein on its binding affinity to various antibodies and the human ACE2 receptor using bioinformatics approaches. The RBD-Ab complexes with experimentally resolved structures were grouped into four clusters with distinct features at sequence and structure level. The performed computational analysis indicates that while single amino acid replacements in RBD may only cause partial impairment of the Abs binding, moreover, limited to specific epitopes, the variants of SARS-CoV-2 with multiple mutations, including some which were already detected in the population, may potentially result in a much broader antigenic escape. Further analysis of the existing RBD variants pointed to the trade-off between ACE2 binding and antigenic escape as a key limiting factor for the emergence of novel SAR-CoV-2 strains, as the naturally occurring mutations in RBD tend to reduce its binding affinity to Abs but not to ACE2. The results provide guidelines for further experimental studies aiming to identify high-risk RBD mutations that allow for an antigenic escape. 相似文献
90.
Anastasiya S. Babkina Irina V. Ostrova Mikhail Ya Yadgarov Artem N. Kuzovlev Andrey V. Grechko Alexey V. Volkov Arkady M. Golubev 《Viruses》2022,14(2)
The increased plasma levels of von Willebrand factor (VWF) in patients with COVID-19 was reported in many studies, and its correlation with disease severity and mortality suggest its important role in the pathogenesis of thrombosis in COVID-19. We performed histological and immunohistochemical studies of the lungs of 29 patients who died from COVID-19. We found a significant increase in the intensity of immunohistochemical reaction for VWF in the pulmonary vascular endothelium when the disease duration was more than 10 days. In the patients who had thrombotic complications, the VWF immunostaining in the pulmonary vascular endothelium was significantly more intense than in nonsurvivors without thrombotic complications. Duration of disease and thrombotic complications were found to be independent predictors of increased VWF immunostaining in the endothelium of pulmonary vessels. We also revealed that bacterial pneumonia was associated with increased VWF staining intensity in pulmonary arterial, arteriolar, and venular endothelium, while lung ventilation was an independent predictor of increased VWF immunostaining in arterial endothelium. The results of the study demonstrated an important role of endothelial VWF in the pathogenesis of thrombus formation in COVID-19. 相似文献