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991.
Mogensen JM Møller KA von Freiesleben P Labuda R Varga E Sulyok M Kubátová A Thrane U Andersen B Nielsen KF 《Journal of industrial microbiology & biotechnology》2011,38(9):1329-1335
Tolypocladium inflatum is known primarily for its production of the cyclosporines that are used as an immunosuppressive drug. However, we report
here the production of the carcinogenic fumonisins B2 and B4 by this biotechnologically relevant fungal genus. These mycotoxins were detected in 11 strains tested from three species:
Tolypocladium inflatum, T. cylindrosporum, and T. geodes. Production of fumonisins by Fusarium spp. and Aspergillus niger is highly medium- and temperature-dependent, so the effect of these parameters on fumonisin production by three T. inflatum strains was studied. Maximum production was achieved on media with high sugar content incubated at 25–30°C. Since these results
demonstrate that fumonisin production could be widespread within the genus Tolypocladium, the potential contamination of commercial cyclosporine preparations with fumonisins needs to be investigated. 相似文献
992.
Yao Y Danna CH Zemp FJ Titov V Ciftci ON Przybylski R Ausubel FM Kovalchuk I 《The Plant cell》2011,23(10):3842-3852
We have previously shown that local exposure of plants to stress results in a systemic increase in genome instability. Here, we show that UV-C-irradiated plants produce a volatile signal that triggers an increase in genome instability in neighboring nonirradiated Arabidopsis thaliana plants. This volatile signal is interspecific, as UV-C-irradiated Arabidopsis plants transmit genome destabilization to naive tobacco (Nicotiana tabacum) plants and vice versa. We report that plants exposed to the volatile hormones methyl salicylate (MeSA) or methyl jasmonate (MeJA) exhibit a similar level of genome destabilization as UV-C-irradiated plants. We also found that irradiated Arabidopsis plants produce MeSA and MeJA. The analysis of mutants impaired in the synthesis and/or response to salicylic acid (SA) and/or jasmonic acid showed that at least one other volatile compound besides MeSA and MeJA can communicate interplant genome instability. The NONEXPRESSOR OF PATHOGENESIS-RELATED GENES1 (npr1) mutant, defective in SA signaling, is impaired in both the production and the perception of the volatile signals, demonstrating a key role for NPR1 as a central regulator of genome stability. Finally, various forms of stress resulting in the formation of necrotic lesions also generate a volatile signal that leads to genomic instability. 相似文献
993.
Multiple myeloma (MM) is an incurable plasma cell (PC) malignancy characterized by the accumulation of monoclonal PCs in the
bone marrow. For deeper understanding of the molecular mechanisms involved in the development of this disease, the influence
of microenvironment, or the prediction of response of tumor PCs to anti-MM treatment, it is possible to use modern technologies
for genomic and proteomic analyses. Due to progress in instrumentation, one of the main tools of proteomic analysis is mass
spectrometry in combination with chosen separation techniques. This review will provide a short survey of the most commonly
used proteomic techniques and show examples of their applications in MM proteome studies. 相似文献
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Jos Barlow Robert M. Ewers Liana Anderson Luiz E. O. C. Aragao Tim R. Baker Emily Boyd Ted R. Feldpausch Emanuel Gloor Anthony Hall Yadvinder Malhi William Milliken Mark Mulligan Luke Parry Toby Pennington Carlos A. Peres Oliver L. Phillips Rosa Maria Roman‐Cuesta Joseph A. Tobias Toby A. Gardner 《Biological reviews of the Cambridge Philosophical Society》2011,86(2):457-474
Developing high‐quality scientific research will be most effective if research communities with diverse skills and interests are able to share information and knowledge, are aware of the major challenges across disciplines, and can exploit economies of scale to provide robust answers and better inform policy. We evaluate opportunities and challenges facing the development of a more interactive research environment by developing an interdisciplinary synthesis of research on a single geographic region. We focus on the Amazon as it is of enormous regional and global environmental importance and faces a highly uncertain future. To take stock of existing knowledge and provide a framework for analysis we present a set of mini‐reviews from fourteen different areas of research, encompassing taxonomy, biodiversity, biogeography, vegetation dynamics, landscape ecology, earth‐atmosphere interactions, ecosystem processes, fire, deforestation dynamics, hydrology, hunting, conservation planning, livelihoods, and payments for ecosystem services. Each review highlights the current state of knowledge and identifies research priorities, including major challenges and opportunities. We show that while substantial progress is being made across many areas of scientific research, our understanding of specific issues is often dependent on knowledge from other disciplines. Accelerating the acquisition of reliable and contextualized knowledge about the fate of complex pristine and modified ecosystems is partly dependent on our ability to exploit economies of scale in shared resources and technical expertise, recognise and make explicit interconnections and feedbacks among sub‐disciplines, increase the temporal and spatial scale of existing studies, and improve the dissemination of scientific findings to policy makers and society at large. Enhancing interaction among research efforts is vital if we are to make the most of limited funds and overcome the challenges posed by addressing large‐scale interdisciplinary questions. Bringing together a diverse scientific community with a single geographic focus can help increase awareness of research questions both within and among disciplines, and reveal the opportunities that may exist for advancing acquisition of reliable knowledge. This approach could be useful for a variety of globally important scientific questions. 相似文献
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Pfister R Sharp S Luben R Welsh P Barroso I Salomaa V Meirhaeghe A Khaw KT Sattar N Langenberg C Wareham NJ 《PLoS medicine》2011,8(10):e1001112
Background
Genetic and epidemiological evidence suggests an inverse association between B-type natriuretic peptide (BNP) levels in blood and risk of type 2 diabetes (T2D), but the prospective association of BNP with T2D is uncertain, and it is unclear whether the association is confounded.Methods and Findings
We analysed the association between levels of the N-terminal fragment of pro-BNP (NT-pro-BNP) in blood and risk of incident T2D in a prospective case-cohort study and genotyped the variant rs198389 within the BNP locus in three T2D case-control studies. We combined our results with existing data in a meta-analysis of 11 case-control studies. Using a Mendelian randomization approach, we compared the observed association between rs198389 and T2D to that expected from the NT-pro-BNP level to T2D association and the NT-pro-BNP difference per C allele of rs198389. In participants of our case-cohort study who were free of T2D and cardiovascular disease at baseline, we observed a 21% (95% CI 3%–36%) decreased risk of incident T2D per one standard deviation (SD) higher log-transformed NT-pro-BNP levels in analysis adjusted for age, sex, body mass index, systolic blood pressure, smoking, family history of T2D, history of hypertension, and levels of triglycerides, high-density lipoprotein cholesterol, and low-density lipoprotein cholesterol. The association between rs198389 and T2D observed in case-control studies (odds ratio = 0.94 per C allele, 95% CI 0.91–0.97) was similar to that expected (0.96, 0.93–0.98) based on the pooled estimate for the log-NT-pro-BNP level to T2D association derived from a meta-analysis of our study and published data (hazard ratio = 0.82 per SD, 0.74–0.90) and the difference in NT-pro-BNP levels (0.22 SD, 0.15–0.29) per C allele of rs198389. No significant associations were observed between the rs198389 genotype and potential confounders.Conclusions
Our results provide evidence for a potential causal role of the BNP system in the aetiology of T2D. Further studies are needed to investigate the mechanisms underlying this association and possibilities for preventive interventions. Please see later in the article for the Editors'' Summary 相似文献1000.
Marín-Vicente C Guerrero-Valero M Nielsen ML Savitski MM Gómez-Fernández JC Zubarev RA Corbalán-García S 《Journal of proteome research》2011,10(2):529-540
PKCα is a key mediator of the neuronal differentiation controlled by NGF and ATP. However, its downstream signaling pathways remain to be elucidated. To identify the signaling partners of PKCα, we analyzed proteins coimmunoprecipitated with this enzyme in PC12 cells differentiated with NGF and ATP and compared them with those obtained with NGF alone or growing media. Mass spectrometry analysis (LC-MS/MS) identified plectin, peripherin, filamin A, fascin, and β-actin as potential interacting proteins. The colocalization of PKCα and its interacting proteins increased when PC12 cells were differentiated with NGF and ATP. Peripherin and plectin organization and the cortical remodeling of β-actin were dramatically affected when PKCα was down-regulated, suggesting that all three proteins might be functional targets of ATP-dependent PKCα signaling. Taken together, these data demonstrate that PKCα is essential for controlling the neuronal development induced by NGF and ATP and interacts with the cytoskeletal components at two levels: assembly of the intermediate filament peripherin and organization of cortical actin. 相似文献