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151.
Grandparentage assignments identify unexpected adfluvial life history tactic contributing offspring to a reintroduced population
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Diversity in life history tactics contributes to the persistence of a population because it helps to protect against stochastic environments by varying individuals in space and time. However, some life history tactics may not be accounted for when assessing the demographic viability of a population. One important factor in demographic viability assessments is cohort replacement rate (CRR), which is defined as the number of future adults produced by an adult. We assessed if precocial resident males (<age‐3) and adfluvial Chinook salmon (Oncorhynchus tshawytscha), adults that reside in freshwater their entire lives, contributed offspring to a reintroduced population from 2008 to 2013. We found that 9 ± 5% of offspring with an unassigned parent remained unexplained after accounting for sources of human error. Using grandparentage assignments, we identified 31 precocial resident males and 48 probable adfluvial Chinook salmon produced by anadromous mate pairs from 2007 to 2012. Previously published CRR estimates for the 2007 and 2008 reintroduced adults, based on only anadromous returning adult offspring, were 0.40 and 0.31, respectively. By incorporating adfluvial females, we found CRR estimates increased by 17% (CRR: 0.46) and 13% (CRR: 0.35) for the 2007 and 2008 cohorts, respectively. 相似文献
152.
Attenuation of pattern recognition receptor signaling is mediated by a MAP kinase kinase kinase
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Sharon C Mithoe Christina Ludwig Michiel JC Pel Mara Cucinotta Alberto Casartelli Malick Mbengue Jan Sklenar Paul Derbyshire Silke Robatzek Corné MJ Pieterse Ruedi Aebersold Frank LH Menke 《EMBO reports》2016,17(3):441-454
Pattern recognition receptors (PRRs) play a key role in plant and animal innate immunity. PRR binding of their cognate ligand triggers a signaling network and activates an immune response. Activation of PRR signaling must be controlled prior to ligand binding to prevent spurious signaling and immune activation. Flagellin perception in Arabidopsis through FLAGELLIN‐SENSITIVE 2 (FLS2) induces the activation of mitogen‐activated protein kinases (MAPKs) and immunity. However, the precise molecular mechanism that connects activated FLS2 to downstream MAPK cascades remains unknown. Here, we report the identification of a differentially phosphorylated MAP kinase kinase kinase that also interacts with FLS2. Using targeted proteomics and functional analysis, we show that MKKK7 negatively regulates flagellin‐triggered signaling and basal immunity and this requires phosphorylation of MKKK7 on specific serine residues. MKKK7 attenuates MPK6 activity and defense gene expression. Moreover, MKKK7 suppresses the reactive oxygen species burst downstream of FLS2, suggesting that MKKK7‐mediated attenuation of FLS2 signaling occurs through direct modulation of the FLS2 complex. 相似文献
153.
154.
Rachna Aneja Antonella Grigoletto Aakansha Nangarlia Adel A. Rashad Steven Wrenn Jeffrey M. Jacobson Gianfranco Pasut Irwin Chaiken 《Journal of peptide science》2019,25(4)
Previously, we reported the discovery of macrocyclic peptide triazoles (cPTs) that bind to HIV‐1 Env gp120, inhibit virus cell infection with nanomolar potencies, and cause irreversible virion inactivation. Given the appealing virus‐killing activity of cPTs and resistance to protease cleavage observed in vitro, we here investigated in vivo pharmacokinetics of the cPT AAR029b. AAR029b was investigated both alone and encapsulated in a PEGylated liposome formulation that was designed to slowly release inhibitor. Pharmacokinetic analysis in rats showed that the half‐life of FITC‐AAR029b was substantial both alone and liposome‐encapsulated, 2.92 and 8.87 hours, respectively. Importantly, liposome‐encapsulated FITC‐AAR029b exhibited a 15‐fold reduced clearance rate from serum compared with the free FITC‐cPT. This work thus demonstrated both the in vivo stability of cPT alone and the extent of pharmacokinetic enhancement via liposome encapsulation. The results obtained open the way to further develop cPTs as long‐acting HIV‐1 inactivators against HIV‐1 infection. 相似文献
155.
Wei Jiang Katherine Y. Zipp Matthew H. Langholtz Michael G. Jacobson 《Global Change Biology Bioenergy》2019,11(9):1086-1097
This paper investigates the spatial heterogeneity of landowners’ willingness to supply three bioenergy crops: switchgrass, Miscanthus, and willow, in the northeastern United States. Spatial heterogeneity might arise for several reasons. For example, landowners closer to bioenergy processing plants might be more likely to be willing to supply bioenergy crops, and landowners who are more willing to supply bioenergy crops may be spatially clustered because they share similar land attributes, demographics, experiences, and/or values. Using high‐resolution GIS data related to the location of pellet plants utilizing bioenergy crops and survey data related to landowners’ characteristics including spatial location, we estimate a spatial probit model to explain the variation in individual‐specific reservation prices (RPs)—the feedstock price at which landowners become willing to supply a bioenergy crop. We find that respondents’ RP is lower the closer they live to their nearest pellet plant and spatial dependency is only present for switchgrass supply. We also identify three economic hotspots (areas with high potential supply and low RPs) for each bioenergy crop. We believe that bioenergy supply chains could be developed around these hotspots. 相似文献
156.
157.
M J Richard L D Davis N L Jacobson 《Comparative biochemistry and physiology. A, Comparative physiology》1990,95(2):275-280
1. Young goats were used to study factors contributing to atherosclerosis. 2. Cholesterol in egg yolk affected plasma cholesterol concentration more than did a similar amount of crystalline cholesterol in the diet. 3. Goats fed high fat diets developed fatty lesions in their aortas. 4. Cholesterol concentration in low-density lipoprotein was greatest in goats fed restricted-calorie diets without exercise, but least in goats fed liberally and exercised. 5. Cholesterol concentration in liver and fat deposition in aorta were greatest in the restricted-calorie, no exercise regime. 相似文献
158.
Mohsin Rahim Arya Y. Nakhe Deveena R. Banerjee Emily M. Overway Karin J. Bosma Jonah C. Rosch James K. Oeser Bo Wang Ethan S. Lippmann David A. Jacobson Richard M. O'Brien Jamey D. Young 《The Journal of biological chemistry》2022,298(4)
Elevated fasting blood glucose (FBG) is associated with increased risks of developing type 2 diabetes (T2D) and cardiovascular-associated mortality. G6PC2 is predominantly expressed in islets, encodes a glucose-6-phosphatase catalytic subunit that converts glucose-6-phosphate (G6P) to glucose, and has been linked with variations in FBG in genome-wide association studies. Deletion of G6pc2 in mice has been shown to lower FBG without affecting fasting plasma insulin levels in vivo. At 5 mM glucose, pancreatic islets from G6pc2 knockout (KO) mice exhibit no glucose cycling, increased glycolytic flux, and enhanced glucose-stimulated insulin secretion (GSIS). However, the broader effects of G6pc2 KO on β-cell metabolism and redox regulation are unknown. Here we used CRISPR/Cas9 gene editing and metabolic flux analysis in βTC3 cells, a murine pancreatic β-cell line, to examine the role of G6pc2 in regulating glycolytic and mitochondrial fluxes. We found that deletion of G6pc2 led to ∼60% increases in glycolytic and citric acid cycle (CAC) fluxes at both 5 and 11 mM glucose concentrations. Furthermore, intracellular insulin content and GSIS were enhanced by approximately two-fold, along with increased cytosolic redox potential and reductive carboxylation flux. Normalization of fluxes relative to net glucose uptake revealed upregulation in two NADPH-producing pathways in the CAC. These results demonstrate that G6pc2 regulates GSIS by modulating not only glycolysis but also, independently, citric acid cycle activity in β-cells. Overall, our findings implicate G6PC2 as a potential therapeutic target for enhancing insulin secretion and lowering FBG, which could benefit individuals with prediabetes, T2D, and obesity. 相似文献
159.
Wissinger B Gamer D Jägle H Giorda R Marx T Mayer S Tippmann S Broghammer M Jurklies B Rosenberg T Jacobson SG Sener EC Tatlipinar S Hoyng CB Castellan C Bitoun P Andreasson S Rudolph G Kellner U Lorenz B Wolff G Verellen-Dumoulin C Schwartz M Cremers FP Apfelstedt-Sylla E Zrenner E Salati R Sharpe LT Kohl S 《American journal of human genetics》2001,69(4):722-737
We recently showed that mutations in the CNGA3 gene encoding the alpha-subunit of the cone photoreceptor cGMP-gated channel cause autosomal recessive complete achromatopsia linked to chromosome 2q11. We now report the results of a first comprehensive screening for CNGA3 mutations in a cohort of 258 additional independent families with hereditary cone photoreceptor disorders. CNGA3 mutations were detected not only in patients with the complete form of achromatopsia but also in incomplete achromats with residual cone photoreceptor function and (rarely) in patients with evidence for severe progressive cone dystrophy. In total, mutations were identified in 53 independent families comprising 38 new CNGA3 mutations, in addition to the 8 mutations reported elsewhere. Apparently, both mutant alleles were identified in 47 families, including 16 families with presumed homozygous mutations and 31 families with two heterozygous mutations. Single heterozygous mutations were identified in six additional families. The majority of all known CNGA3 mutations (39/46) are amino acid substitutions compared with only four stop-codon mutations, two 1-bp insertions and one 3-bp in-frame deletion. The missense mutations mostly affect amino acids conserved among the members of the cyclic nucleotide gated (CNG) channel family and cluster at the cytoplasmic face of transmembrane domains (TM) S1 and S2, in TM S4, and in the cGMP-binding domain. Several mutations were identified recurrently (e.g., R277C, R283W, R436W, and F547L). These four mutations account for 41.8% of all detected mutant CNGA3 alleles. Haplotype analysis suggests that the R436W and F547L mutant alleles have multiple origins, whereas we found evidence that the R283W alleles, which are particularly frequent among patients from Scandinavia and northern Italy, have a common origin. 相似文献
160.
Free major histocompatibility complex class I heavy chain is preferentially targeted for degradation by human T-cell leukemia/lymphotropic virus type 1 p12(I) protein
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Johnson JM Nicot C Fullen J Ciminale V Casareto L Mulloy JC Jacobson S Franchini G 《Journal of virology》2001,75(13):6086-6094
Human T-cell leukemia virus type 1 (HTLV-1) establishes a persistent infection in the host despite a vigorous virus-specific immune response. Here we demonstrate that an HTLV-1-encoded protein, p12(I), resides in the endoplasmic reticulum (ER) and Golgi and physically binds to the free human major histocompatibility complex class I heavy chains (MHC-I-Hc) encoded by the HLA-A2, -B7, and -Cw4 alleles. As a result of this interaction, the newly synthesized MHC-I-Hc fails to associate with beta(2)-microglobulin and is retrotranslocated to the cytosol, where it is degraded by the proteasome complex. Targeting of the free MHC-I-Hc, and not the MHC-I-Hc-beta(2)-microglobulin complex, by p12(I) represents a novel mechanism of viral interference and disrupts the intracellular trafficking of MHC-I, which results in a significant decrease in surface levels of MHC-I on human T-cells. These findings suggest that the interaction of p12(I) with MHC-1-Hc may interfere with antigen presentation in vivo and facilitate escape of HTLV-1-infected cells from immune recognition. 相似文献