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61.
This report describes the production and characterization of 13 rodent monoclonal antibodies to the human erythrocyte anion transport protein AE1 (syn. band 3). Eleven antibodies (4 murine and 7 rat) recognize epitopes dependent on the integrity of the third extracellular loop of the protein. Two antibodies (1 murine and 1 rat) recognize epitopes on the N-terminal cytoplasmic domain. Quantitative binding studies using radioiodinated IgG and Fab fragments of antibodies to extracellular epitopes on AE1 ranged from 77,000 to 313,000 (IgG) and from 241,000 to 772,000 (Fab) molecules bound at saturation. The results indicate that the epitopes recognized by different antibodies vary in their accessibility and suggest that there is heterogeneity in the organization of individual AE1 molecules in the red blood cell membrane. Quantitative binding studies on South East Asian ovalocytes using several antibodies to AE1 and an anti-Wrb show a marked reduction in the number of antibody molecules bound at saturation. These results are consistent with the existence of highly cooperative interactions between transmembrane domains of AE1 in normal erythrocytes and the disruption of these interactions in the variant AE1 found in South East Asian ovalocytes. 相似文献
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Rabia Shahswar Gernot Beutel Piroska Klement Alina Rehberg Razif Gabdoulline Christian Koenecke Dominik Markel Hendrik Eggers Matthias Eder Michael Stadler Lothar Hambach Steve Ehrlich Gudrun Göhring Brigitte Schlegelberger Elke Dammann Marlene Reuter Martin Wichmann Blerina Neziri Arnold Ganser Felicitas Thol Michael Heuser 《British journal of haematology》2020,188(3):e11-e15
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Bloom of resident antibiotic-resistant bacteria in soil following manure fertilization 总被引:2,自引:0,他引:2
Nikolina Udikovic-Kolic Fabienne Wichmann Nichole A. Broderick Jo Handelsman 《Proceedings of the National Academy of Sciences of the United States of America》2014,111(42):15202-15207
The increasing prevalence of antibiotic-resistant bacteria is a global threat to public health. Agricultural use of antibiotics is believed to contribute to the spread of antibiotic resistance, but the mechanisms by which many agricultural practices influence resistance remain obscure. Although manure from dairy farms is a common soil amendment in crop production, its impact on the soil microbiome and resistome is not known. To gain insight into this impact, we cultured bacteria from soil before and at 10 time points after application of manure from cows that had not received antibiotic treatment. Soil treated with manure contained a higher abundance of β-lactam–resistant bacteria than soil treated with inorganic fertilizer. Functional metagenomics identified β-lactam–resistance genes in treated and untreated soil, and indicated that the higher frequency of resistant bacteria in manure-amended soil was attributable to enrichment of resident soil bacteria that harbor β-lactamases. Quantitative PCR indicated that manure treatment enriched the blaCEP-04 gene, which is highly similar (96%) to a gene found previously in a Pseudomonas sp. Analysis of 16S rRNA genes indicated that the abundance of Pseudomonas spp. increased in manure-amended soil. Populations of other soil bacteria that commonly harbor β-lactamases, including Janthinobacterium sp. and Psychrobacter pulmonis, also increased in response to manure treatment. These results indicate that manure amendment induced a bloom of certain antibiotic-resistant bacteria in soil that was independent of antibiotic exposure of the cows from which the manure was derived. Our data illustrate the unintended consequences that can result from agricultural practices, and demonstrate the need for empirical analysis of the agroecosystem.Agriculture affects human health through both the consumption and production of food for the human diet. Manure from pig and cattle farms is commonly used as a substitute for inorganic nitrogen and phosphorus fertilizers for agricultural crops worldwide, especially in organic farming practices (1–6). With the increasing consumer demand for organically produced food, the use of animal manure, which conforms to organic conventions, will likely increase in the future. According to the National Organic Program, raw manure may be used up to 90–120 d before harvest, depending on the crop, and composted manure may be applied at any time. There are no restrictions on the source of manure (1).Animal manure is an important reservoir of antibiotic-resistant bacteria, antibiotic-resistance genes (collectively known as the “resistome”), and pathogens (2, 7–12). Although antibiotic use increases antibiotic-resistance genes and resistant bacteria in manure (13–16), antibiotic-resistant bacteria are also abundant in manure from animals with no history of antibiotic treatment, indicating the natural presence of bacteria intrinsically resistant to antibiotics in animal gastrointestinal tracts (2, 17, 18).There is increasing concern about the use of manure as an agricultural amendment because of its possible contribution to the pool of resistance genes to resident soil bacteria and pathogens (2, 19). Antibiotic-resistance genes from the soil resistome can enter the food chain via contaminated crops or groundwater (5, 20), and have potential consequences for human health if transferred to human pathogens. Studies assessing the impact of fertilization with pig manure on the soil resistome have shown that excessive application of manure from farms with intensive sulfonamide use can lead to an increase of antibiotic-resistance genes in soil (2, 3); however, most studies have found that such increases are transient when the manure is applied at recommended rates (2, 21, 22). Cow manure from dairy farms, which use β-lactam antibiotics predominantly to prevent and treat diseases (23), is commonly used in crop production, but its impact on the soil resistome has yet to be investigated.Along with its impact on the soil resistome, the application of manure can affect the composition and functional properties of soil microbial communities, as has been demonstrated by community fingerprinting (21, 24). Recent advances in DNA-based analysis, such as metagenomics and quantitative PCR (qPCR), offer greater precision in such studies, enabling identification of affected community members (25) and their resistance genes (4).In the present study, we assessed the impact of cow manure on the composition and resistance profiles of bacterial communities in soil. Our results show that manure from cows that had not been treated with antibiotics increased the populations of resident soil bacteria harboring genes for resistance to β-lactam antibiotics, whereas inorganic fertilizers did not. These results demonstrate the complexity, and at times nonintuitive consequences, of agricultural practices. 相似文献
66.
Incidence of invasive meningococcal disease is low in Germany at 0.5 cases/100,000 inhabitants. Serogroup B (MenB) is most common, causing 70% of cases, with highest incidence in infants (5.9/100,000). In 2013, a MenB vaccine was licensed in Europe. To assess pediatricians’ attitudes towards MenB vaccination and its potential use in Germany we conducted a nationwide cross-sectional survey among 5677 pediatricians. Of 3107 participants (response: 55%), 79.1% would recommend a MenB vaccination to parents, with 66.7% favoring a schedule at 6, 8 and 12 months over 2, 3, 4 and 12 months (13.4%). Administration separately from other vaccines was preferred (63.2%); 38.5% feared that a recommendation would lead to refusal of other recommended vaccinations. In conclusion, pediatricians showed distinct preferences regarding possible integration of MenB vaccination into the existent immunization schedule. As physicians play a crucial role in the implementation, findings will be useful in decision-making regarding potential introduction. 相似文献
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Alban Flachot Arash Akbarinia Heiko H. Schütt Roland W. Fleming Felix A. Wichmann Karl R. Gegenfurtner 《Journal of vision》2022,22(4)
Color constancy is our ability to perceive constant colors across varying illuminations. Here, we trained deep neural networks to be color constant and evaluated their performance with varying cues. Inputs to the networks consisted of two-dimensional images of simulated cone excitations derived from three-dimensional (3D) rendered scenes of 2,115 different 3D shapes, with spectral reflectances of 1,600 different Munsell chips, illuminated under 278 different natural illuminations. The models were trained to classify the reflectance of the objects. Testing was done with four new illuminations with equally spaced CIEL*a*b* chromaticities, two along the daylight locus and two orthogonal to it. High levels of color constancy were achieved with different deep neural networks, and constancy was higher along the daylight locus. When gradually removing cues from the scene, constancy decreased. Both ResNets and classical ConvNets of varying degrees of complexity performed well. However, DeepCC, our simplest sequential convolutional network, represented colors along the three color dimensions of human color vision, while ResNets showed a more complex representation. 相似文献
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Felix G. Meinel Julian L. Wichmann U. Joseph Schoepf Francesca Pugliese Ullrich Ebersberger Gladys G. Lo Yeon Hyeon Choe Yining Wang Christian Tesche Sabrina Segreto Wolfgang G. Kunz Kolja M. Thierfelder Fabian Bamberg Carlo N. De Cecco 《Journal of Cardiovascular Computed Tomography》2017,11(1):16-24