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71.
P.?G.?MasonEmail author M.?J.?W.?Cock B.?I.?P.?Barratt J.?N.?Klapwijk J.?C.?van?Lenteren J.?Brodeur K.?A.?Hoelmer G.?E.?Heimpel 《BioControl》2018,63(1):149-154
The Nagoya Protocol is a supplementary agreement to the Convention on Biological Diversity that provides a framework for the effective implementation of the fair and equitable sharing of benefits arising out of the utilization of genetic resources, including invertebrate biological control agents. The Protocol came into force on 12 October 2014, and requires signatories and countries acceding to the Protocol to develop a legal framework to ensure access to genetic resources, benefit-sharing and compliance. The biological control community of practice needs to comply with access and benefit sharing regulations arising under the Protocol. The IOBC Global Commission on Biological Control and Access and Benefit Sharing has prepared this best practices guide for the use and exchange of invertebrate biological control genetic resources for the biological control community of practice to demonstrate due diligence in responding to access and benefit sharing requirements, and to reassure the international community that biological control is a very successful and environmentally safe pest management method based on the use of biological diversity. We propose that components of best practice include: collaborations to facilitate information exchange about what invertebrate biological control agents are available and where they may be obtained; knowledge sharing through freely available databases that document successes (and failures); cooperative research to develop capacity in source countries; and transfer of production technology to provide opportunities for small-scale economic activity. We also provide a model concept agreement that can be used for scientific research and non-commercial release into nature where access and benefit sharing regulations exist, and a model policy for provision of invertebrate biological control agents to other parties where access and benefit sharing regulations are not restrictive or do not exist. 相似文献
72.
Refugia are areas relatively buffered from contemporary climate change that enable the persistence of valued physical, ecological, or sociocultural resources. Spatially identifying refugia is important for conservation and applied management. Yet the concept of refugia has not been broadly extended to marine ecosystems. Here, we analyze data from a unique and long‐term (1999–2015) standardized survey of pelagic marine and anadromous species off Oregon and Washington in the northern California Current to identify such refugia. We use quantitative approaches to assess locations with high species richness and community persistence relative to local and basin‐scale environmental fluctuations. We have identified a potential climate change refugial zone along the continental shelf of Washington State in the Northeastern Pacific Ocean, characterized by a species‐rich community with low interannual temporal community change. This region contrasts with adjacent areas to the south and offshore that have lower species richness, and higher temporal species community change. Also, using spatially variant generalized additive mixed models, we identify areas with species compositions that are more influenced by basin‐scale climatic fluctuations than others. We propose that upwelling regions with retentive topographic features, such as wide continental shelves, can function as marine refugia for pelagic fauna, whereas offshore locations are potentially more climatically sensitive and experience high temporal change in species composition. Further identification of these marine refugia using in situ data for pelagic biodiversity and climatically sensitive areas can help guide management in the face of inevitable climatically driven change. 相似文献
73.
Feed Your Friends: Do Plant Exudates Shape the Root Microbiome? 总被引:9,自引:0,他引:9
74.
Prey selection by age-0 walleye pollock, Theragra chalcogramma, in nearshore waters of the Gulf of Alaska 总被引:1,自引:0,他引:1
Richard D. Brodeur 《Environmental Biology of Fishes》1998,51(2):175-186
Juvenile walleye pollock, Theragra chalcogramma, is the dominant forage fish on the continental shelf of the Gulf of Alaska,
yet little is known about the feeding habits of this important interval of pollock life history. The taxonomic composition
and size of prey found in the stomachs of age-0 juveniles collected at three nearshore locations in the Gulf of Alaska in
September 1990 were compared to the composition and size of zooplankton collected in concurrent plankton tows. The maximum
length of prey consumed increased dramatically over the length range of pollock examined (58–110 mm) from approximately 7
mm to 30 mm, due mainly to the consumption of large euphausiids and chaetognaths by the bigger individuals. The maximum width
of prey changed little over this size range although there was a general increase in prey width with increasing predator size.
The minimum prey length and width did not change with increasing fish size. Juvenile pollock generally selected the larger
prey sizes relative to what was available. Juvenile pollock showed a marked preference for adult euphausiids and decapod larvae
and an avoidance of copepods and chaetognaths relative to the numbers collected in net tows. These results are discussed relative
to the feeding ecology of these juvenile fishes.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
75.
Tyler D. Rudolph Pierre Drapeau Louis Imbeau Vincent Brodeur Sonia Légaré Martin-Hugues St-Laurent 《Biodiversity and Conservation》2017,26(5):1179-1198
Conserving species-at-risk requires quantifiable knowledge of the key drivers of population change. Non-linear demographic responses to habitat loss have been documented for many species and may serve to establish quantitative habitat thresholds for management purposes. In Canada, boreal populations of woodland caribou are considered threatened; Environment Canada’s empirical model of calf recruitment–range disturbance suggests that at least 65% undisturbed habitat is required to ensure viability. We tested the relationship upon which this conservation guideline is based by pairing demographic estimates with range conditions over a 10-year period for three boreal caribou populations. Our objectives were (1) to evaluate evidence of intra-population demographic responses to fluctuations in range quality over time; (2) to evaluate inter-population differences in demographic responses to cumulative range disturbances; and (3) to evaluate the sensitivity of disturbance tolerance thresholds to variation in local population demography. We found strong evidence in support of the disturbance–recruitment relationship for within-population responses over time (R2 = 0.77). Mixed effects logistic regression modeling revealed variations in local population responses to cumulative habitat depletion. Range-specific disturbance thresholds derived from Monte Carlo simulations were highly elastic in response to observed variation in local population demography, suggesting that 65% undisturbed habitat is insufficient when adult female survival and/or sex ratio is suboptimal. Study populations were determined to be not self-sustaining (Pr(λ ≥ 0.99) = 37–47%). Adult survival was comparable to estimates reported elsewhere despite Aboriginal harvesting for subsistence purposes. Results underscored potential trade-offs between forest harvesting and wildlife habitat conservation. Protection and restoration of sufficient quantities of undisturbed habitat, particularly via road reclamation, is essential for caribou population recovery. 相似文献
76.
Engineered,highly reactive substrates of microbial transglutaminase enable protein labeling within various secondary structure elements 下载免费PDF全文
Natalie M. Rachel Daniela Quaglia Éric Lévesque André B. Charette Joelle N. Pelletier 《Protein science : a publication of the Protein Society》2017,26(11):2268-2279
Microbial transglutaminase (MTG) is a practical tool to enzymatically form isopeptide bonds between peptide or protein substrates. This natural approach to crosslinking the side‐chains of reactive glutamine and lysine residues is solidly rooted in food and textile processing. More recently, MTG's tolerance for various primary amines in lieu of lysine have revealed its potential for site‐specific protein labeling with aminated compounds, including fluorophores. Importantly, MTG can label glutamines at accessible positions in the body of a target protein, setting it apart from most labeling enzymes that react exclusively at protein termini. To expand its applicability as a labeling tool, we engineered the B1 domain of Protein G (GB1) to probe the selectivity and enhance the reactivity of MTG toward its glutamine substrate. We built a GB1 library where each variant contained a single glutamine at positions covering all secondary structure elements. The most reactive and selective variants displayed a >100‐fold increase in incorporation of a recently developed aminated benzo[a]imidazo[2,1,5‐cd]indolizine‐type fluorophore, relative to native GB1. None of the variants were destabilized. Our results demonstrate that MTG can react readily with glutamines in α‐helical, β‐sheet, and unstructured loop elements and does not favor one type of secondary structure. Introducing point mutations within MTG's active site further increased reactivity toward the most reactive substrate variant, I6Q‐GB1, enhancing MTG's capacity to fluorescently label an engineered, highly reactive glutamine substrate. This work demonstrates that MTG‐reactive glutamines can be readily introduced into a protein domain for fluorescent labeling. 相似文献
77.
78.
Testing competing measures of profitability for mobile resources 总被引:1,自引:0,他引:1
Optimal diet theory often fails to predict a forager’s diet choice when prey are mobile. Because they escape or defend themselves,
mobile prey are likely to increase the forager’s handling time, thereby decreasing its fitness gain rate. Many animals have
been shown to select their prey so as to maximize either their fitness gain or their fitness gain rate. However, no study
has yet compared directly these two measures of profitability by generating testable predictions about the choice of the forager.
Under laboratory conditions, we compared these two measures of profitability, using the aphid parasitoid Aphidius colemani and its host, Myzus persicae. Fitness gain was calculated for parasitoids developing in each host instar by measuring life-history traits such as developmental
time, sex ratio and fecundity. Fitness gain rate was estimated by dividing fitness gain by handling time, the time required
to subdue the host. Fourth instar aphids provided the best fitness gain to parasitoids, whereas second instar aphids were
the most profitable in terms of fitness gain rate. Host choice tests showed that A. colemani females preferred second instar hosts, suggesting that their decision maximizes fitness gain rate over fitness gain. Our
results indicate that fitness gain rate is a reliable predictor of animal’s choice for foragers exploiting resources that
impose additional time cost due to their mobility.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
79.
To Quyen Truong Mathieu R. Brodeur Louise Falstrault David Rhainds Louise Brissette 《Journal of cellular biochemistry》2009,108(4):906-915
Oxidized LDL (OxLDL) that are positively associated with the risk of developing cardiovascular diseases are ligands of scavenger receptor‐class B type I (SR‐BI) and cluster of differentiation‐36 (CD36) which can be found in caveolae. The contribution of these receptors in human hepatic cell is however unknown. The HepG2 cell, a human hepatic parenchymal cell model, expresses these receptors and is characterized by a very low level of caveolin‐1. Our aim was to define the contribution of human CD36, SR‐BI, and caveolin‐1 in the metabolism of OxLDL in HepG2 cells and conversely the effects of OxLDL on the levels/localization of these receptors. By comparing mildly (M)‐ and heavily (H)‐OxLDL metabolism between control HepG2 cells and HepG2 cells overexpressing CD36, SR‐BI, or caveolin‐1, we found that (1) CD36 increases M‐ and H‐OxLDL‐protein uptake; (2) SR‐BI drives M‐OxLDL through a degradation pathway at the expense of the cholesterol ester (CE) selective uptake pathway; (3) caveolin‐1 increases M‐ and H‐OxLDL‐protein uptake and decreases CE selective uptake from M‐OxLDL. Also, incubation with M‐ or H‐OxLDL decreases the levels of SR‐BI and LDL‐receptor in control HepG2 cells which can be overcome by caveolin‐1 expression. In addition, OxLDL move CD36 from low to high buoyant density membrane fractions, as well as caveolin‐1 in cells overexpressing this protein. Thus, hepatic caveolin‐1 expression has significant effects on OxLDL metabolism and on lipoprotein receptor levels. J. Cell. Biochem. 108: 906–915, 2009. © 2009 Wiley‐Liss, Inc. 相似文献
80.
Mark J. Ammirati Kim M. Andrews David D. Boyer Anne M. Brodeur Dennis E. Danley Shawn D. Doran Bernard Hulin Shenping Liu R. Kirk McPherson Stephen J. Orena Janice C. Parker Jana Polivkova Xiayang Qiu Carolyn B. Soglia Judith L. Treadway Maria A. VanVolkenburg Donald C. Wilder David W. Piotrowski 《Bioorganic & medicinal chemistry letters》2009,19(7):1991-1995
A series of 4-substituted proline amides was synthesized and evaluated as inhibitors of dipeptidyl pepdidase IV for the treatment of type 2 diabetes. (3,3-Difluoro-pyrrolidin-1-yl)-[(2S,4S)-(4-(4-pyrimidin-2-yl-piperazin-1-yl)-pyrrolidin-2-yl]-methanone (5) emerged as a potent (IC50 = 13 nM) and selective compound, with high oral bioavailability in preclinical species and low plasma protein binding. Compound 5, PF-00734200, was selected for development as a potential new treatment for type 2 diabetes. 相似文献