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111.
Han A Mulder Lars R?nneg?rd W Freddy Fikse Roel F Veerkamp Erling Strandberg 《遗传、选种与进化》2013,45(1):23
Background
Genetic variation for environmental sensitivity indicates that animals are genetically different in their response to environmental factors. Environmental factors are either identifiable (e.g. temperature) and called macro-environmental or unknown and called micro-environmental. The objectives of this study were to develop a statistical method to estimate genetic parameters for macro- and micro-environmental sensitivities simultaneously, to investigate bias and precision of resulting estimates of genetic parameters and to develop and evaluate use of Akaike’s information criterion using h-likelihood to select the best fitting model.Methods
We assumed that genetic variation in macro- and micro-environmental sensitivities is expressed as genetic variance in the slope of a linear reaction norm and environmental variance, respectively. A reaction norm model to estimate genetic variance for macro-environmental sensitivity was combined with a structural model for residual variance to estimate genetic variance for micro-environmental sensitivity using a double hierarchical generalized linear model in ASReml. Akaike’s information criterion was constructed as model selection criterion using approximated h-likelihood. Populations of sires with large half-sib offspring groups were simulated to investigate bias and precision of estimated genetic parameters.Results
Designs with 100 sires, each with at least 100 offspring, are required to have standard deviations of estimated variances lower than 50% of the true value. When the number of offspring increased, standard deviations of estimates across replicates decreased substantially, especially for genetic variances of macro- and micro-environmental sensitivities. Standard deviations of estimated genetic correlations across replicates were quite large (between 0.1 and 0.4), especially when sires had few offspring. Practically, no bias was observed for estimates of any of the parameters. Using Akaike’s information criterion the true genetic model was selected as the best statistical model in at least 90% of 100 replicates when the number of offspring per sire was 100. Application of the model to lactation milk yield in dairy cattle showed that genetic variance for micro- and macro-environmental sensitivities existed.Conclusion
The algorithm and model selection criterion presented here can contribute to better understand genetic control of macro- and micro-environmental sensitivities. Designs or datasets should have at least 100 sires each with 100 offspring. 相似文献112.
113.
The Zaire ebolavirus protein VP24 was previously demonstrated to inhibit alpha/beta interferon (IFN-α/β)- and IFN-γ-induced nuclear accumulation of tyrosine-phosphorylated STAT1 (PY-STAT1) and to inhibit IFN-α/β- and IFN-γ-induced gene expression. These properties correlated with the ability of VP24 to interact with the nuclear localization signal receptor for PY-STAT1, karyopherin α1. Here, VP24 is demonstrated to interact not only with overexpressed but also with endogenous karyopherin α1. Mutational analysis demonstrated that VP24 binds within the PY-STAT1 binding region located in the C terminus of karyopherin α1. In addition, VP24 was found to inhibit PY-STAT1 binding to both overexpressed and endogenous karyopherin α1. We assessed the binding of both PY-STAT1 and the VP24 proteins from Zaire, mouse-adapted Zaire, and Reston Ebola viruses for interaction with all six members of the human karyopherin α family. We found, in contrast to previous studies, that PY-STAT1 can interact not only with karyopherin α1 but also with karyopherins α5 and α6, which together comprise the NPI-1 subfamily of karyopherin αs. Similarly, all three VP24s bound and inhibited PY-STAT1 interaction with karyopherins α1, α5, and α6. Consistent with their ability to inhibit the karyopherin-PY-STAT1 interaction, Zaire, mouse-adapted Zaire, and Reston Ebola virus VP24s displayed similar capacities to inhibit IFN-β-induced gene expression in human and mouse cells. These findings suggest that VP24 inhibits interaction of PY-STAT1 with karyopherins α1, α5, or α6 by binding within the PY-STAT1 binding region of the karyopherins and that this function is conserved among the VP24 proteins of different Ebola virus species. 相似文献
114.
Moore MM Honma M Clements J Bolcsfoldi G Burlinson B Cifone M Clarke J Clay P Doppalapudi R Fellows M Gollapudi B Hou S Jenkinson P Muster W Pant K Kidd DA Lorge E Lloyd M Myhr B O'Donovan M Riach C Stankowski LF Thakur AK Van Goethem F;Mouse Lymphoma Assay Workgroup IWGT 《Mutation research》2007,627(1):36-40
The Mouse Lymphoma Assay (MLA) Workgroup of the International Workshop on Genotoxicity Testing (IWGT), comprised of experts from Japan, Europe and the United States, met on September 9, 2005, in San Francisco, CA, USA. This meeting of the MLA Workgroup was devoted to reaching a consensus on issues involved with 24-h treatment. Recommendations were made concerning the acceptable values for the negative/solvent control (mutant frequency, cloning efficiency and suspension growth) and the criteria to define an acceptable positive control response. Consensus was also reached concerning the use of the global evaluation factor (GEF) and appropriate statistical trend analysis to define positive and negative responses for the 24-h treatment. The Workgroup agreed to continue their support of the International Committee on Harmonization (ICH) recommendation that the MLA assay should include a 24-h treatment (without S-9) in those situations where the short treatment (3-4 h) gives negative results. 相似文献
115.
Rivault F Liébert C Burger A Hoegy F Abdallah MA Schalk IJ Mislin GL 《Bioorganic & medicinal chemistry letters》2007,17(3):640-644
Using synthetic functionalized analogues of pyochelin, a siderophore common to several pathogenic Pseudomonas and Burkholderia species, four fluoroquinolone-pyochelin conjugates were efficiently synthesized and evaluated for their biological activities. 相似文献
116.
Daphne Brul Clizia Villano Laura J. Davies Lucie Trd Justine Claverie Marie‐Claire Hloir Annick Chiltz Marielle Adrian Benoît Darblade Pablo Tornero Lena Stransfeld Freddy Boutrot Cyril Zipfel Ian B. Dry Benoit Poinssot 《Plant biotechnology journal》2019,17(4):812-825
Chitin, a major component of fungal cell walls, is a well‐known pathogen‐associated molecular pattern (PAMP) that triggers defense responses in several mammal and plant species. Here, we show that two chitooligosaccharides, chitin and chitosan, act as PAMPs in grapevine (Vitis vinifera) as they elicit immune signalling events, defense gene expression and resistance against fungal diseases. To identify their cognate receptors, the grapevine family of LysM receptor kinases (LysM‐RKs) was annotated and their gene expression profiles were characterized. Phylogenetic analysis clearly distinguished three V. vinifera LysM‐RKs (VvLYKs) located in the same clade as the Arabidopsis CHITIN ELICITOR RECEPTOR KINASE1 (AtCERK1), which mediates chitin‐induced immune responses. The Arabidopsis mutant Atcerk1, impaired in chitin perception, was transformed with these three putative orthologous genes encoding VvLYK1‐1, ‐2, or ‐3 to determine if they would complement the loss of AtCERK1 function. Our results provide evidence that VvLYK1‐1 and VvLYK1‐2, but not VvLYK1‐3, functionally complement the Atcerk1 mutant by restoring chitooligosaccharide‐induced MAPK activation and immune gene expression. Moreover, expression of VvLYK1‐1 in Atcerk1 restored penetration resistance to the non‐adapted grapevine powdery mildew (Erysiphe necator). On the whole, our results indicate that the grapevine VvLYK1‐1 and VvLYK1‐2 participate in chitin‐ and chitosan‐triggered immunity and that VvLYK1‐1 plays an important role in basal resistance against E. necator. 相似文献
117.
Allan J. Walkey Serkalem Demissie Dilip Shah Freddy Romero Leah Puklin Ross S. Summer 《PloS one》2014,9(9)
Objective
Adiponectin (APN) is an anti-inflammatory hormone derived from adipose tissue that attenuates acute lung injury in rodents. In this study, we investigated the association between circulating APN and outcomes among patients with acute respiratory distress syndrome (ARDS).Methods
We performed a retrospective cohort study using data and plasma samples from participants in the multicenter ARDS Network Fluid and Catheter Treatment Trial.Results
Plasma APN concentrations were measured in 816 (81.6%) trial participants at baseline and in 568 (56.8%) subjects at both baseline and day 7 after enrollment. Clinical factors associated with baseline APN levels in multivariable-adjusted models included sex, body mass index, past medical history of cirrhosis, and central venous pressure (model R2 = 9.7%). We did not observe an association between baseline APN and either severity of illness (APACHE III) or extent of lung injury (Lung Injury Score). Among patients who received right heart catheterization (n = 384), baseline APN was inversely related to mean pulmonary artery pressure (β = −0.015, R2 1.5%, p = 0.02); however, this association did not persist in multivariable models (β = −0.009, R2 0.5%, p = 0.20). Neither baseline APN levels [HR per quartile1.04 (95% CI 0.91–1.18), p = 0.61], nor change in APN level from baseline to day 7 [HR 1.04 (95% CI 0.89–1.23), p = 0.62)] were associated with 60 day mortality in Cox proportional hazards regression models. However, subgroup analysis identified an association between APN and mortality among patients who developed ARDS from extra-pulmonary etiologies [HR per quartile 1.31 (95% CI 1.08–1.57)]. APN levels did not correlate with mortality among patients developing ARDS in association with direct pulmonary injury [HR 0.96 (95% CI 0.83–1.13)], pinteraction = 0.016.Conclusions
Plasma APN levels did not correlate with disease severity or mortality in a large cohort of patients with ARDS. However, higher APN levels were associated with increased mortality among patients developing ARDS from extra-pulmonary etiologies. 相似文献118.
Elhaseen Elamin Ad Masclee Freddy Troost Harm-Jan Pieters Daniel Keszthelyi Katarina Aleksa Jan Dekker Daisy Jonkers 《PloS one》2014,9(9)
Background
Ethanol-induced gut barrier disruption is associated with several gastrointestinal and liver disorders.Aim
Since human data on effects of moderate ethanol consumption on intestinal barrier integrity and involved mechanisms are limited, the objectives of this study were to investigate effects of a single moderate ethanol dose on small and large intestinal permeability and to explore the role of mitogen activated protein kinase (MAPK) pathway as a primary signaling mechanism.Methods
Intestinal permeability was assessed in 12 healthy volunteers after intraduodenal administration of either placebo or 20 g ethanol in a randomised cross-over trial. Localization of the tight junction (TJ) and gene expression, phosphorylation of the MAPK isoforms p38, ERK and JNK as indicative of activation were analyzed in duodenal biopsies. The role of MAPK was further examined in vitro using Caco-2 monolayers.Results
Ethanol increased small and large intestinal permeability, paralleled by redistribution of ZO-1 and occludin, down-regulation of ZO-1 and up-regulation of myosin light chain kinase (MLCK) mRNA expression, and increased MAPK isoforms phosphorylation. In Caco-2 monolayers, ethanol increased permeability, induced redistribution of the junctional proteins and F-actin, and MAPK and MLCK activation, as indicated by phosphorylation of MAPK isoforms and myosin light chain (MLC), respectively, which could be reversed by pretreatment with either MAPK inhibitors or the anti-oxidant L-cysteine.Conclusions
Administration of moderate ethanol dosage can increase both small and colon permeability. Furthermore, the data indicate a pivotal role for MAPK and its crosstalk with MLCK in ethanol-induced intestinal barrier disruption.Trial Registration
ClinicalTrials.gov NCT00928733相似文献119.
Tom Hellebuyck Katleen Van Steendam Dieter Deforce Mark Blooi Filip Van Nieuwerburgh Evelien Bullaert Richard Ducatelle Freddy Haesebrouck Frank Pasmans An Martel 《PloS one》2014,9(12)
Devrieseasis caused by Devriesea agamarum is a highly prevalent disease in captive desert lizards, resulting in severe dermatitis and in some cases mass mortality. In this study, we assessed the contribution of autovaccination to devrieseasis control by evaluating the capacity of 5 different formalin-inactivated D. agamarum vaccines to induce a humoral immune response in bearded dragons (Pogona vitticeps). Each vaccine contained one of the following adjuvants: CpG, incomplete Freund''s, Ribi, aluminium hydroxide, or curdlan. Lizards were administrated one of the vaccines through subcutaneous injection and booster vaccination was given 3 weeks after primo-vaccination. An indirect ELISA was developed and used to monitor lizard serological responses. Localized adverse effects following subcutaneous immunization were observed in all but the Ribi adjuvanted vaccine group. Following homologous experimental challenge, the incomplete Freund''s as well as the Ribi vaccine were observed to confer protection in bearded dragons against the development of D. agamarum associated septicemia but not against dermatitis. Subsequently, two-dimensional gelelectrophoresis followed by immunoblotting and mass spectrometry was conducted with serum obtained from 3 lizards that showed seroconversion after immunisation with the Ribi vaccine. Fructose-bisphosphate aldolase and aldo-keto reductase of D. agamarum reacted with serum from the latter lizards. Based on the demonstrated seroconversion and partial protection against D. agamarum associated disease following the use of formalin-inactivated vaccines as well as the identification of target antigens in Ribi vaccinated bearded dragons, this study provides promising information towards the development of a vaccination strategy to control devrieseasis in captive lizard collections. 相似文献
120.
del Puerto F Nishizawa JE Kikuchi M Roca Y Avilas C Gianella A Lora J Velarde FU Miura S Komiya N Maemura K Hirayama K 《PLoS neglected tropical diseases》2012,6(3):e1587