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91.
Jessica AB van Nies Rute B Marques Stella Trompet Zuzana de Jong Fina AS Kurreeman Rene EM Toes J Wouter Jukema Tom WJ Huizinga Annette HM van der Helm-van Mil 《Arthritis research & therapy》2010,12(2):R38
Introduction
Recently an association between a genetic variation in TRAF1/C5 and mortality from sepsis or cancer was found in rheumatoid arthritis (RA). The most prevalent cause of death, cardiovascular disease, may have been missed in that study, since patients were enrolled at an advanced disease stage. Therefore, we used an inception cohort of RA patients to investigate the association between TRAF1/C5 and cardiovascular mortality, and replicate the findings on all-cause mortality. As TRAF1/C5 associated mortality may not be restricted to RA, we also studied a large cohort of non-RA patients. 相似文献92.
Interaction of maternal environment and allelic differences in seed vigour genes determines seed performance in Brassica oleracea 下载免费PDF全文
Sajjad Awan Steven Footitt William E. Finch‐Savage 《The Plant journal : for cell and molecular biology》2018,94(6):1098-1108
Seed vigour is a key trait essential for the production of sustainable and profitable crops. The genetic basis of variation in seed vigour has recently been determined in Brassica oleracea, but the relative importance of the interaction with parental environment is unknown. We produced seeds under a range of maternal environments, including global warming scenarios. Lines were compared that had the same genetic background, but different alleles (for high and low vigour) at the quantitative trait loci responsible for determining seed vigour by altering abscisic acid (ABA) content and sensitivity. We found a consistent effect of beneficial alleles across production environments; however, environmental stress during production also had a large impact that enhanced the genetic difference in seed performance, measured as germination speed, resistance to controlled deterioration and induction of secondary dormancy. Environmental interaction with allelic differences in key genes that determine ABA content and sensitivity develops a continuity in performance from rapid germination through to failure to complete germination, and increasing depths of seed dormancy. The genetic–environmental interaction revealed provides a robust mechanism of bet‐hedging to minimize environmental risk during subsequent germination, and this could have facilitated the rapid change in seed behaviour (reduced dormancy and rapid germination) observed during crop domestication. 相似文献
93.
Background and Aims
In complex communities, organisms often form mutualisms with multiple different partners simultaneously. Non-additive effects may emerge among species linked by these positive interactions. Ants commonly participate in mutualisms with both honeydew-producing insects (HPI) and their extrafloral nectary (EFN)-bearing host plants. Consequently, HPI and EFN-bearing plants may experience non-additive benefits or costs when these groups co-occur. The outcomes of these interactions are likely to be influenced by variation in preferences among ants for honeydew vs. nectar. In this study, a test was made for non-additive effects on HPI and EFN-bearing plants resulting from sharing exotic ant guards. Preferences of the dominant exotic ant species for nectar vs. honeydew resources were also examined.Methods
Ant access, HPI and nectar availability were manipulated on the EFN-bearing shrub, Morinda citrifolia, and ant and HPI abundances, herbivory and plant growth were assessed. Ant-tending behaviours toward HPI across an experimental gradient of nectar availability were also tracked in order to investigate mechanisms underlying ant responses.Key Results
The dominant ant species, Anoplolepis gracilipes, differed from less invasive ants in response to multiple mutualists, with reductions in plot-wide abundances when nectar was reduced, but no response to HPI reduction. Conversely, at sites where A. gracilipes was absent or rare, abundances of less invasive ants increased when nectar was reduced, but declined when HPI were reduced. Non-additive benefits were found at sites dominated by A. gracilipes, but only for M. citrifolia plants. Responses of HPI at these sites supported predictions of the non-additive cost model. Interestingly, the opposite non-additive patterns emerged at sites dominated by other ants.Conclusions
It was demonstrated that strong non-additive benefits and costs can both occur when a plant and herbivore share mutualist partners. These findings suggest that broadening the community context of mutualism studies can reveal important non-additive effects and increase understanding of the dynamics of species interactions. 相似文献94.
Evidence for an Elongation/Reduction/C1-Elimination Pathway in the Biosynthesis of n-Heptane in Xylem of Jeffrey Pine 总被引:1,自引:0,他引:1 下载免费PDF全文
The biosynthetic pathway to n-heptane was investigated by examining the effect of the [beta]-keto acyl-acyl carrier protein synthase inhibitor (2R,3S)-2,3-epoxy-4-oxo-7E,10E-dodecadienamide (cerulenin), a thiol reagent ([beta]-mercaptoethanol), and an aldehydetrapping reagent (hydroxylamine) on the biosynthesis of n-[14C]heptane and putative intermediates in xylem sections of Jeffrey pine (Pinus jeffreyi Grev.& Balf.) incubated with [14C]acetate. Cerulenin inhibited C18 fatty acid biosynthesis but had relatively little effect on radiolabel incorporation into C8 fatty acyl groups and n-heptane. [beta]-Mercaptoethanol inhibited n-heptane biosynthesis, with a corresponding accumulation of radiolabel into both octanal and 1-octanol, whereas hydroxylamine inhibited both n-heptane and 1-octanol biosynthesis, with radiolabel accumulation in octyl oximes. [14C]Octanal was converted to both n-heptane and 1-octanol when incubated with xylem sections, whereas [14C]1-octanol was converted to octanal and n-heptane in a hydroxylamine-sensitive reaction. These results suggest a pathway for the biosynthesis of n-heptane whereby acetate is polymerized via a typical fatty acid synthase reaction sequence to yield a C8 thioester, which subsequently undergoes a two-electron reduction to generate a free thiol and octanal, the latter of which alternately undergoes an additional, reversible reduction to form 1-octanol or loss of C1 to generate n-heptane. 相似文献
95.
Jennifer D. Watts Mary Farina John S. Kimball Luke D. Schiferl Zhihua Liu Kyle A. Arndt Donatella Zona Ashley Ballantyne Eugénie S. Euskirchen Frans-Jan W. Parmentier Manuel Helbig Oliver Sonnentag Torbern Tagesson Janne Rinne Hiroki Ikawa Masahito Ueyama Hideki Kobayashi Torsten Sachs Daniel F. Nadeau John Kochendorfer Marcin Jackowicz-Korczynski Anna Virkkala Mika Aurela Roisin Commane Brendan Byrne Leah Birch Matthew S. Johnson Nima Madani Brendan Rogers Jinyang Du Arthur Endsley Kathleen Savage Ben Poulter Zhen Zhang Lori M. Bruhwiler Charles E. Miller Scott Goetz Walter C. Oechel 《Global Change Biology》2023,29(7):1870-1889
Arctic-boreal landscapes are experiencing profound warming, along with changes in ecosystem moisture status and disturbance from fire. This region is of global importance in terms of carbon feedbacks to climate, yet the sign (sink or source) and magnitude of the Arctic-boreal carbon budget within recent years remains highly uncertain. Here, we provide new estimates of recent (2003–2015) vegetation gross primary productivity (GPP), ecosystem respiration (Reco), net ecosystem CO2 exchange (NEE; Reco − GPP), and terrestrial methane (CH4) emissions for the Arctic-boreal zone using a satellite data-driven process-model for northern ecosystems (TCFM-Arctic), calibrated and evaluated using measurements from >60 tower eddy covariance (EC) sites. We used TCFM-Arctic to obtain daily 1-km2 flux estimates and annual carbon budgets for the pan-Arctic-boreal region. Across the domain, the model indicated an overall average NEE sink of −850 Tg CO2-C year−1. Eurasian boreal zones, especially those in Siberia, contributed to a majority of the net sink. In contrast, the tundra biome was relatively carbon neutral (ranging from small sink to source). Regional CH4 emissions from tundra and boreal wetlands (not accounting for aquatic CH4) were estimated at 35 Tg CH4-C year−1. Accounting for additional emissions from open water aquatic bodies and from fire, using available estimates from the literature, reduced the total regional NEE sink by 21% and shifted many far northern tundra landscapes, and some boreal forests, to a net carbon source. This assessment, based on in situ observations and models, improves our understanding of the high-latitude carbon status and also indicates a continued need for integrated site-to-regional assessments to monitor the vulnerability of these ecosystems to climate change. 相似文献
96.
G. Mattson E. Conklin S. Desai G. Nielander M. D. Savage S. Morgensen 《Molecular biology reports》1993,17(3):167-183
The various aspects of chemical crosslinking are addressed. Crosslinker reactivity, specificity, spacer arm length and solubility characteristics are detailed. Considerations for choosing one of these crosslinkers for a particular application are given as well as reaction conditions and practical tips for use of each category of crosslinkers.Abbreviations ABH
azidobenzoyl hydrazide
- ANB- NOS
N-5-azido-2-nitrobenzoyloxysuccinimide
- ASIB
1-(p-azidosalicylamido)-4-(iodoacetamido)butane
- ASBA
4-(p-azidosalicylamido)butylamine
- APDP
N-[4-(p-azidosalicylamido) butyl]-3(2-pyridyldithio)propionamide
- APG
p-azidophenyl glyoxal monohydrate
- BASED
bis-[-(4-azidosalicylamido)ethyl] disulfide
- BMH
bismaleimidohexane
- BS3
bis(sulfosuccinimidyl) suberate
- BSOCOES
bis[2-(succinimidooxycarbonyloxy)ethyl]sulfone
- DCC
N,N-dicyclohexylcarbodiimide
- DFDNB
1,5-difluoro-2,4-dinitrobenzene
- DMA
dimethyl adipimidate·2HCl
- DMP
dimethyl pimelimidate·2HCl
- DMS
dimethyl suberimidate·2HCl
- DPDPB
1,4-di-(3,2-pyridyldithio)propionamido butane
- DMF
dimethylformamide
- DMSO
dimethylsulfoxide
- DSG
disuccinimidyl glutarate
- DSP
dithiobis(succinimidylpropionate)
- DSS
disuccinimidyl suberate
- DST
disuccinimidyl tartarate
- DTSSP
3,3-dithiobis (sulfosuccinimidylpropionate)
- DTBP
dimethyl 3,3-dithiobispropionimidate·2HCl
- EDC or EDAC
1-ethyl-3-(3-dimethylaminopropyl)carbodimide hydrochloride
- EDTA
ethylenediaminetetraacetic acid disodium salt, dihydrate
- EGS
ethylene glycolbis(succinimidylsuccinate)
- GMBS
N--maleimidobutyryloxysuccinimide ester
- HSAB
N-hydroxysuccinimidyl-4-azidobenzoate
- HEPES
4-(2-hydroxyethyl)-1-piperazineethanesulfonic acid
- MBS
m-maleimidobenzoyl-N-hydroxysuccinimide ester
- MES
4-morpholineethanesulfonic acid
- NHS
N-hydroxysuccinimide
- NHS-ASA
N-hydroxysuccinimidyl-4-azidosalicylic acid
- PMFS
phenylmethylsulfonyl fluoride
- PNP-DTP
p-nitrophenyl-2-diazo-3,3,3-trifluoropropionate
- SAED
sulfosuccinimidyl 2-(7-azido-4-methylcoumarin-3-acetamide) ethyl-1,3-dithiopropionate
- SADP
N-succinimdyl (4-azidophenyl)1,3-dithiopropionate
- SAND
sulfosuccinimidyl 2-(m-azido-o-nitrobenzamido)-ethyl-1,3-dithiopropionate
- SANPAH
N-succinimidyl-6(4-azido-2-nitrophenyl-amino)hexanoate
- SASD
sulfosuccinimidyl 2-(p-azidosalicylamido)ethyl-1,3-dithiopropionate
- SATA
N-succinimidyl-S-acetylthioacetate
- SDBP
N-hydroxysuccinimidyl-2,3-dibromopropionate
- SIAB
N-succinimidyl(4-iodoacetyl)aminobenzoate
- SMCC
succinimidyl 4-(N-maleimidomethyl)cyclohexane-1-carboxylate
- SMPB
succinimidyl 4-(p-maleimidophenyl) butyrate
- SMPT
4-succinimidyloxycarbonyl--methyl--(2-pyridyldithio)-toluene
- sulfo-BSOCOES
bis[2-sulfosuccinimidooxycarbonyloxy) ethyl]sulfone
- sulfo-DST
disulfosuccinimidyl tartarate
- sulfo-EGS
ethylene glycolbis(sulfosuccinimidylsuccinate)
- sulfo-GMBS
N--maleimidobutyryloxysulfosuccinimide ester
- sulfo-MBS
m-maleimidobenzoyl-N-hydroxysulfosuccinimide ester
- sulfo-SADP
sulfosuccinimidyl(4-azidophenyldithio)propionate
- sulfo-SAMCA
sulfosuccinimidyl 7-azido-4-methylcoumarin-3-acetate
- sulfo-SANPAH
sulfosuccinimidyl 6-(4-azido-2-nitrophenylamino)hexanoate
- sulfo-SIAB
sulfosuccinimidyl(4-iodoacetyl)aminobenzoate
- sulfo-SMPB
sulfo-succinimidyl 4-(p-maleimidophenyl)butyrate
- sulfo-SMCC
sulfosuccinimidyl 4-(N-maleimidomethyl)cyclohexane-1-carboxylate
- SPDP
N-succinimidyl 3-(2-pyridyldithio)propionate 相似文献
97.
The status of glutathione (GSH) was studied in isolated rat liver mitochondria under conditions which induce a permeability transition. This transition, which is inhibited by cyclosporin A (CyA), requires the presence of Ca2+ and an inducing agent such as near physiological levels (3 mM) of inorganic phosphate (Pi). The transition is characterized by an increased inner membrane permeability to some low molecular weight solutes and by large amplitude swelling under some experimental conditions. Addition of 70 microM Ca2+ and 3 mM Pi to mitochondria resulted in mitochondrial swelling and extensive release of GSH that was recovered in the extramitochondrial medium as GSH. Both swelling and the efflux of mitochondrial GSH were prevented by CyA. Incubation of mitochondria in the presence of Ca2+, Pi, and GSH followed by addition of CyA provided a mechanism to load mitochondria with exogenous GSH that was greater than the rate of uptake by untreated mitochondria. Thus, GSH efflux from mitochondria may occur under toxicological and pathological conditions in which mitochondria are exposed to elevated Ca2+ in the presence of near physiological concentrations of Pi through a nonspecific pore. Cyclical opening and closing of the pore could also provide a mechanism for uptake of GSH by mitochondria. 相似文献
98.
Svenson KL Ahituv N Durgin RS Savage H Magnani PA Foreman O Paigen B Peters LL 《Journal of lipid research》2008,49(11):2452-2462
In an effort to discover new mouse models of cardiovascular disease using N-ethyl-N-nitrosourea (ENU) mutagenesis followed by high-throughput phenotyping, we have identified a new mouse mutation, C699Y, in the LDL receptor (Ldlr), named wicked high cholesterol (WHC). When WHC was compared with the widely used Ldlr knockout (KO) mouse, notable phenotypic differences between strains were observed, such as accelerated atherosclerotic lesion formation and reduced hepatosteatosis in the ENU mutant after a short exposure to an atherogenic diet. This loss-of-function mouse model carries a single base mutation in the Ldlr gene on an otherwise pure C57BL/6J (B6) genetic background, making it a useful new tool for understanding the pathophysiology of atherosclerosis and for evaluating additional genetic modifiers regulating hyperlipidemia and atherogenesis. Further investigation of genomic differences between the ENU mutant and KO strains may reveal previously unappreciated sequence functionality. 相似文献
99.
Determining fine‐scale migratory connectivity and habitat selection for a migratory songbird by using new GPS technology 下载免费PDF全文
K. C. Fraser A. Shave A. Savage A. Ritchie K. Bell J. Siegrist J. D. Ray K. Applegate M. Pearman 《Journal of avian biology》2017,48(3):339-345
Migratory aerial insectivores are among the fastest declining avian groups, but our understanding of these trends has been limited by poor knowledge of migratory connectivity and the identification of critical habitat across the vast distances they travel annually. Using new, archival GPS loggers, we tracked individual purple martins Progne subis from breeding colonies across North America to determine precise (< > 10 m) locations of migratory and overwintering roost locations in South America and to test hypotheses for fine‐scale migratory connectivity and habitat use. We discovered weak migratory connectivity at the roost scale, and extensive, fine‐scale mixing of birds in the Amazon from distant (> 2000 km) breeding sites, with some individuals sharing the same roosting trees. Despite vast tracts of contiguous forest in this region, birds occupied a much more limited habitat, with most (56%) roosts occurring on small habitat islands that were strongly associated with water. Only 17% of these roosts were in current protected areas. These data reflect a critical advance in our ability to remotely determine precise migratory connectivity and habitat selection across vast spatial scales, enhancing our understanding of population dynamics and enabling more effective conservation of species at risk. 相似文献
100.