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891.
David L. Vergara‐Tabares Javier M. Cordier Marcos A. Landi George Olah Javier Nori 《Global Change Biology》2020,26(8):4251-4262
Human advance on natural habitats is a major cause of biodiversity loss. This transformation process represents a profound change in wooded environments, disrupting original communities of flora and fauna. Many species are highly dependent on forests, especially parrots (Psittaciformes) with almost a third of their species threatened by extinction. Most parrot species occur in tropical and subtropical forests, and given the forest dependence of most species, this is the main reason why habitat loss has been highlighted as the main threat for the group. Such habitat loss acts in synergy with other important threats (e.g., logging and poaching), which become especially problematic in certain developing countries along tropical latitudes. In this study, we used available information on parrot distributions, species traits, IUCN assessment, habitat loss and timber extraction for different periods, and distribution of protected areas, to determine conservation hotspots for the group, and analyze potential changes in the conservation status of these species. We detected four conservation hotspots for parrots: two in the Neotropics and two in Oceania, all of them facing different degrees of threat in regard of current habitat loss and agricultural trends. Our results suggest that the future of the group is subject to policymaking in specific regions, especially in the northeastern Andes and the Atlantic Forest. In addition, we predicted that agricultural expansion will have a further negative effect on the conservation status of parrots, pushing many parrot species to the edge of extinction in the near future. Our results have conservation implications by recommending protected areas in specific parrot conservation hotspots. Our recommendations to mitigate conservation risks to this group of umbrella species would also benefit many other coexisting species as well. 相似文献
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Rafaella Grenfell Donald A. Harn Smanla Tundup Akram Da'dara Liliane Siqueira Paulo Marcos Zech Coelho 《PLoS neglected tropical diseases》2013,7(2)
Background
Schistosomiasis mansoni is a debilitating and sometimes fatal disease. Accurate diagnosis plays a key role in patient management and infection control. However, currently available parasitological methods are laborious and lack sensitivity. The selection of target antigen candidates has turned out to be a promising tool for the development of more sensitive diagnostic methods. In our previous investigations, the use of crude antigens led to false-positive results. Recently, focus has been given to highly purified Schistosoma mansoni antigens, especially to circulating antigens.Method
Thus, our main goal was to test different types of circulating cathodic antigen glycoprotein (CCA), as “crude antigen,” the protein chain of recombinant CCA and two individual peptides. These schistosome proteins/peptides were tested in a new diagnostic method employing immunomagnetic separation based on the improvement of antigen–antibody binding.Principal Findings
Use of recombinant CCA as a diagnostic antigen allowed us to develop a diagnostic assay with high sensitivity and specificity with no false-negative results. Interestingly, the “crude antigen” worked as a good marker for control of cure after praziquantel treatment.Conclusions/Significance
Our new diagnostic method was superior to enzyme-linked immunosorbent assay in diagnosing low endemicity patients. 相似文献895.
Swetlana Sirko Gwendolyn Behrendt Pia Annette Johansson Pratibha Tripathi Marcos Romualdo Costa Sarah Bek Christophe Heinrich Steffen Tiedt Dilek Colak Martin Dichgans Isabel Rebekka Fischer Nikolaus Plesnila Matthias Staufenbiel Christian Haass Marina Snapyan Armen Saghatelyan Li-Huei Tsai André Fischer Magdalena Götz 《Cell Stem Cell》2013,12(4):426-439
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Albert E. Fernandes Muritiba Manuel Iori Silvano Martello Marcos J. Negreiros Gomes 《Flexible Services and Manufacturing Journal》2013,25(3):443-461
A relevant logistic issue in the organization of a fair is to determine how stands have to be placed in the exhibition space so as to satisfy all constraints on security, ease of access, services, and so on, while maximizing the revenues coming from the exhibitors. We consider in particular the problem of allocating the maximum number of stands by satisfying all the constraints required by practical implementations. We examine a number of real-world cases, and show how basic mathematical programming models can be improved to handle specific requests from the organizers. We report the solutions obtained through an original decision support system, that embeds a number of algorithms to solve the various cases by reduction to one or more linear programs. 相似文献
898.
Thomas Botton Iwei Yeh Tyrrell Nelson Swapna S. Vemula Alyssa Sparatta Maria C. Garrido Maryline Allegra Stephane Rocchi Philippe Bahadoran Timothy H. McCalmont Philip E. LeBoit Elizabeth A. Burton Gideon Bollag Robert Ballotti Boris C. Bastian 《Pigment cell & melanoma research》2013,26(6):845-851
BRAF is the most prevalent oncogene and an important therapeutic target in melanoma. In some cancers, BRAF is activated by rearrangements that fuse its kinase domain to 5′ partner genes. We examined 848 comparative genomic hybridization profiles of melanocytic tumors and found copy number transitions within BRAF in 10 tumors, of which six could be further characterized by sequencing. In all, the BRAF kinase domain was fused in‐frame to six N‐terminal partners. No other mutations were identified in melanoma oncogenes. One of the seven melanoma cell lines without known oncogenic mutations harbored a similar BRAF fusion, which constitutively activated the MAP kinase pathway. Sorafenib, but not vemurafenib, could block MAP kinase pathway activation and proliferation of the cell line at clinically relevant concentrations, whereas BRAFV600E mutant melanoma cell lines were significantly more sensitive to vemurafenib. The patient from whom the cell line was derived showed a durable clinical response to sorafenib. 相似文献
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Marcos Vinícius da Silva Amanda A. Figueiredo Juliana R. Machado Lúcio C. Castellano Patricia B. D. Alexandre Rafael F. Oliveira Gladstone E. L. Faria Sanívia A. L. Pereira Denise B. R. Rodrigues Virmondes Rodrigues Jr 《PloS one》2013,8(6)