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991.
Jonathan G. Lundgren Alison Huber Robert N. Wiedenmann 《Agricultural and Forest Entomology》2005,7(1):53-60
Abstract 1 Coleomegilla maculata DeGeer feeds on corn pollen in the field, but the degree to which this predator relies on corn pollen as part of its diet is not well understood. We quantified the amount of pollen consumed by C. maculata second, third and fourth instars and adults in the field. 2 Laboratory experiments were conducted to determine the digestion rate and duration of different stadia or stages using temperature regimens that reflected field conditions during anthesis. Coleomegilla maculata larvae and adults were collected from the field and the amount of pollen in their digestive tracts was determined gravimetrically. The rate of digestion, duration of each life stage and the field observations were used to estimate the amount of pollen consumed by second, third and fourth instars and adults. 3 Our models estimate that larvae consume 0.66, 1.67 and 3.30 mg of pollen during the second, third and fourth stadia, respectively. Adults consumed an estimated 13.15 mg during anthesis. 4 The relevance of our results to ecological risk assessment of transgenic insecticidal corn and predator life history strategies is discussed. The results presented here are a first attempt to quantify pollen consumption by a predator, and future areas of research are suggested. 相似文献
992.
Alison M Jackson Joe Boutell Neil Cooley Mingyue He 《Briefings in Functional Genomics and Prot》2004,2(4):308-319
The use of cell-free expression systems as an alternative to cell-based methods for protein production is greatly facilitating studies of protein functions. Recent improvements to cell-free systems, and the development of cell-free protein display and microarray technologies, have led to cell-free protein synthesis becoming a powerful tool for large-scale analysis of proteins. This paper reviews the most commonly used cell-free systems and their applications in proteomics. 相似文献
993.
Crop connectivity under climate change: future environmental and geographic risks of potato late blight in Scotland 下载免费PDF全文
Peter Skelsey David E. L. Cooke James S. Lynott Alison K. Lees 《Global Change Biology》2016,22(11):3724-3738
The impact of climate change on dispersal processes is largely ignored in risk assessments for crop diseases, as inoculum is generally assumed to be ubiquitous and nonlimiting. We suggest that consideration of the impact of climate change on the connectivity of crops for inoculum transmission may provide additional explanatory and predictive power in disease risk assessments, leading to improved recommendations for agricultural adaptation to climate change. In this study, a crop‐growth model was combined with aerobiological models and a newly developed infection risk model to provide a framework for quantifying the impact of future climates on the risk of disease occurrence and spread. The integrated model uses standard meteorological variables and can be easily adapted to various crop pathosystems characterized by airborne inoculum. In a case study, the framework was used with data defining the spatial distribution of potato crops in Scotland and spatially coherent, probabilistic climate change data to project the future connectivity of crop distributions for Phytophthora infestans (causal agent of potato late blight) inoculum and the subsequent risk of infection. Projections and control recommendations are provided for multiple combinations of potato cultivar and CO2 emissions scenario, and temporal and spatial averaging schemes. Overall, we found that relative to current climatic conditions, the risk of late blight will increase in Scotland during the first half of the potato growing season and decrease during the second half. To guide adaptation strategies, we also investigated the potential impact of climate change‐driven shifts in the cropping season. Advancing the start of the potato growing season by 1 month proved to be an effective strategy from both an agronomic and late blight management perspective. 相似文献
994.
Evolutionary potential of the extrinsic incubation period of dengue virus in Aedes aegypti 下载免费PDF全文
Yixin H. Ye Stephen F. Chenoweth Alison M. Carrasco Scott L. Allen Francesca D. Frentiu Andrew F. van den Hurk Nigel W. Beebe Elizabeth A. McGraw 《Evolution; international journal of organic evolution》2016,70(11):2459-2469
Dengue fever is the most common arboviral disease worldwide. It is caused by dengue viruses (DENV) and the mosquito Aedes aegypti is its primary vector. One of the most powerful determinants of a mosquito's ability to transmit DENV is the length of the extrinsic incubation period (EIP), the time it takes for a virus to be transmitted by a mosquito after consuming an infected blood meal. Here, we repeatedly measured DENV load in the saliva of individual mosquitoes over their lifetime and used this in combination with a breeding design to determine the extent to which EIP might respond to the evolutionary forces of drift and selection. We demonstrated that genetic variation among mosquitoes contributes significantly to transmission potential and length of EIP. We reveal that shorter EIP is genetically correlated with reduced mosquito lifespan, highlighting negative life‐history consequences for virus‐infected mosquitoes. This work highlights the capacity for local genetic variation in mosquito populations to evolve and to dramatically affect the nature of human outbreaks. It also provides the impetus for isolating mosquito genes that determine EIP. More broadly, our dual experimental approach offers new opportunities for studying the evolutionary potential of transmission traits in other vector/pathogen systems. 相似文献
995.
Matthias Schmitz Elisabeth Ebert Katharina Stoeck André Karch Steven Collins Miguel Calero Theodor Sklaviadis Jean-Louis Laplanche Ewa Golanska Ines Baldeiras Katsuya Satoh Raquel Sanchez-Valle Anna Ladogana Anders Skinningsrud Anna-Lena Hammarin Eva Mitrova Franc Llorens Yong Sun Kim Alison Green Inga Zerr 《Molecular neurobiology》2016,53(4):2189-2199
996.
Synthesis and Utilization of Trialkylammonium‐Substituted Cyclodextrins as Water‐Soluble Chiral NMR Solvating Agents for Anionic Compounds 下载免费PDF全文
Alison E. Dowey Cira Mollings Puentes Mira Carey‐Hatch Keyana L. Sandridge Nikhil B. Krishna Thomas J. Wenzel 《Chirality》2016,28(4):299-305
Cationic trialkylammonium‐substituted α‐, β‐, and γ‐cyclodextrins containing trimethyl‐, triethyl‐, and tri‐n‐propylammonium substituent groups were synthesized and analyzed for utility as water‐soluble chiral nuclear magnetic resonance (NMR) solvating agents. Racemic and enantiomerically pure (3‐chloro‐2‐hydroxypropyl)trimethyl‐, triethyl‐, and tri‐n‐propyl ammonium chloride were synthesized from the corresponding trialkyl amine hydrochloride and either racemic or enantiomerically pure epichlorohydrin. The ammonium salts were then reacted with α‐, β‐, and γ‐cyclodextrins at basic pH to provide the corresponding randomly substituted cationic cyclodextrins. The 1H NMR spectra of a range of anionic, aromatic compounds was recorded with the cationic cyclodextrins. Cyclodextrins with a single stereochemistry at the hydroxy group on the (2‐hydroxypropyl)trialkylammonium chloride substituent were often but not always more effective than the corresponding cyclodextrin in which the C‐2 position was racemic. In several cases, the larger triethyl or tri‐n‐propyl derivatives were more effective than the corresponding trimethyl derivative at causing enantiomeric differentiation. None of the cyclodextrin derivatives were consistently the most effective for all of the anionic compounds studied. Chirality 28:299–305, 2016. © 2016 Wiley Periodicals, Inc. 相似文献
997.
Jordan S. Read Jordan I. Walker Alison P. Appling David L. Blodgett Emily K. Read Luke A. Winslow 《Ecography》2016,39(4):354-360
Geoprocessing of large gridded data according to overlap with irregular landscape features is common to many large‐scale ecological analyses. The geoknife R package was created to facilitate reproducible analyses of gridded datasets found on the U.S. Geological Survey Geo Data Portal web application or elsewhere, using a web‐enabled workflow that eliminates the need to download and store large datasets that are reliably hosted on the Internet. The package provides access to several data subset and summarization algorithms that are available on remote web processing servers. Outputs from geoknife include spatial and temporal data subsets, spatially‐averaged time series values filtered by user‐specified areas of interest, and categorical coverage fractions for various land‐use types. 相似文献
998.
Targeted redox inhibition of protein phosphatase 1 by Nox4 regulates eIF2α‐mediated stress signaling 下载免费PDF全文
Celio XC Santos Anne D Hafstad Matteo Beretta Min Zhang Chris Molenaar Jola Kopec Dina Fotinou Thomas V Murray Andrew M Cobb Daniel Martin Maira Zeh Silva Narayana Anilkumar Katrin Schröder Catherine M Shanahan Alison C Brewer Ralf P Brandes Eric Blanc Maddy Parsons Vsevelod Belousov Richard Cammack Robert C Hider Roberto A Steiner Ajay M Shah 《The EMBO journal》2016,35(3):319-334
999.
1000.
Alison E. Mahan Madeleine F. Jennewein Todd Suscovich Kendall Dionne Jacquelynne Tedesco Amy W. Chung Hendrik Streeck Maria Pau Hanneke Schuitemaker Don Francis Patricia Fast Dagna Laufer Bruce D. Walker Lindsey Baden Dan H. Barouch Galit Alter 《PLoS pathogens》2016,12(3)
Antibody effector functions, such as antibody-dependent cellular cytotoxicity, complement deposition, and antibody-dependent phagocytosis, play a critical role in immunity against multiple pathogens, particularly in the absence of neutralizing activity. Two modifications to the IgG constant domain (Fc domain) regulate antibody functionality: changes in antibody subclass and changes in a single N-linked glycan located in the CH2 domain of the IgG Fc. Together, these modifications provide a specific set of instructions to the innate immune system to direct the elimination of antibody-bound antigens. While it is clear that subclass selection is actively regulated during the course of natural infection, it is unclear whether antibody glycosylation can be tuned, in a signal-specific or pathogen-specific manner. Here, we show that antibody glycosylation is determined in an antigen- and pathogen-specific manner during HIV infection. Moreover, while dramatic differences exist in bulk IgG glycosylation among individuals in distinct geographical locations, immunization is able to overcome these differences and elicit antigen-specific antibodies with similar antibody glycosylation patterns. Additionally, distinct vaccine regimens induced different antigen-specific IgG glycosylation profiles, suggesting that antibody glycosylation is not only programmable but can be manipulated via the delivery of distinct inflammatory signals during B cell priming. These data strongly suggest that the immune system naturally drives antibody glycosylation in an antigen-specific manner and highlights a promising means by which next-generation therapeutics and vaccines can harness the antiviral activity of the innate immune system via directed alterations in antibody glycosylation in vivo. 相似文献