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91.
92.
Common bunt is known to cause grain yield and quality losses in wheat due to bunt ball formation and infestation of the grain. The aim of this study is to identify for sources of resistance to common bunt in wheat genotypes using phytopathological and molecular methods. In general, studied 60 Kazakh and foreign wheat genotypes were found 15 samples with the Bt9, Bt8 and Bt11 genes. Carriers of the Bt10 gene include the five varieties. The four resistance genes, Bt8, Bt10, Bt11, Bt9, and Bt10 were identified in the Karasai variety. Phytopathological and molecular screening of Kazakh and foreign wheat genotypes selected 18 with genes for resistance to the disease. According to evaluation on an artificial infection 19 varieties showed an immune type of reaction. These varieties will be used in breeding programs as donors to create resistant varieties against the common bunt. Thus, approaches can reduce the level of fungicides use and the most effective method to control the common bunt.  相似文献   
93.
TANK-binding kinase 1 (TBK1) and inducible IκB-kinase (IKK-i) are central regulators of type-I interferon induction. They are associated with three adaptor proteins called TANK, Sintbad (or TBKBP1) and NAP1 (or TBKBP2, AZI2) whose functional relationship to TBK1 and IKK-i is poorly understood. We performed a systematic affinity purification-mass spectrometry approach to derive a comprehensive TBK1/IKK-i molecular network. The most salient feature of the network is the mutual exclusive interaction of the adaptors with the kinases, suggesting distinct alternative complexes. Immunofluorescence data indicated that the individual adaptors reside in different subcellular locations. TANK, Sintbad and NAP1 competed for binding of TBK1. The binding site for all three adaptors was mapped to the C-terminal coiled-coil 2 region of TBK1. Point mutants that affect binding of individual adaptors were used to reconstitute TBK1/IKK-i-deficient cells and dissect the functional relevance of the individual kinase-adaptor edges within the network. Using a microarray-derived gene expression signature of TBK1 in response virus infection or poly(I∶C) stimulation, we found that TBK1 activation was strictly dependent on the integrity of the TBK1/TANK interaction.  相似文献   
94.
Background:The use of chimeric proteins that selectively interact with various immune cell receptors to treat oncology patients has increased. One effective way to obtain recombinant proteins is to use the E. coli expression system. However, in eukaryotic protein production in E. coli, several difficulties arise that can be solved by fusing the target protein with thioredoxin. Thioredoxin can enhance solubility, but its large size can lead to an erroneous assessment of protein solubility, folding, and activity. The present study examined the ligand-binding activity of PD-L1, and CTLA-4 receptors fused with thioredoxin.Methods:The de novo synthesized genes of the extracellular domains of the PD-L1 and CTLA-4 were cloned into the pET28 and pET32 expression plasmids and used to transform E. coli BL21 cells. Purified recombinant proteins were characterized by western blotting, LC-MS/MS spectrometry, and ELISA.Results:Amino acid sequence comparisons of the recombinant proteins obtained by LC-MS/MS with the SwissProt database resulted in the highest comparison scores from 4950 to 13396. The binding efficiencies of recombinant human B7-1 Fc to rCTLA-4 and rTrx-CTLA-4 proteins in ELISA did not differ significantly. Similar results were obtained with recombinant rhesus monkey PD-1 hFc against rPD-L1 and rTrx-PD-L1.Conclusion:Recombinant proteins specifically reacted with recombinant human B7-1 Fc and recombinant rhesus monkey PD-1 hFc. The fusion of thioredoxin with recombinant proteins through linkers slightly affected the activity of the extracellular domains of CTLA-4 and PD-L1.Key Words: Chimeric Protein, CTLA-4, PD-L1, Protein Refolding, Recombinant Protein, Thioredoxin  相似文献   
95.
Following the rapid uptake of contaminants in the first few hours of exposure, plants typically attempt to cope with the toxic burden by releasing part of the sorbed material back into the environment. The present study investigates the general trends in the release profiles of different metal(loid)s in the aquatic macrophyte Lemna minor and details the correlations that exist between the release of metal(loid) species. Water samples with distinct contamination profiles were taken from Nilüfer River (Bursa, Turkey), Yeniça?a Lake (Bolu, Turkey), and Bey?ehir Lake (Konya, Turkey) and used for release studies; 36 samples were tested in total. Accumulation and release profiles were monitored over five days for 11 metals and a metalloid (208Pb, 111Cd, 52Cr,53Cr,60Ni,63Cu,65Cu,75As,55Mn, 137Ba, 27Al, 57Fe, 66Zn,68Zn) and correlation, cluster and principal component analyses were employed to determine the factors that affect the release of these elements. Release profiles of the tested metal(loid)s were largely observed to be distinct; however, strong correlations have been observed between certain metal pairs (Cr/Ni, Cr/Cu, Zn/Ni) and principal component analysis was able to separate the metal(loid)s into three well-resolved groups based on their release.  相似文献   
96.
A stable bacterial association isolated from a sulfur block sample of the Astrakhan gas processing complex was able to utilize n-alkanes as the sole carbon and energy source at low pH. Hydrocarbon-dependent growth occurred at pH 1.6–5.5 (optimum at pH 2.5) and 20–50°C (optimum at 30–35°C). Analysis of the 16S rRNA gene fragments isolated from the total DNA of the enrichment by PCR-DGGE revealed the nucleotide sequences most closely related to extreme acidophilic chemolithotrophs Acidithiobacillus thiooxidans and Sulfobacillus sp. (98–99% similarity) and the sequences exhibiting high similarity to those of slowly growing actinobacteria Mycobacterium europaeum and M. parascrofulaceum (98%). Capacity of any of these organisms for hydrocarbon oxidation has not been reported previously. The taxonomic position of the 16S rRNA gene fragments from the enrichment culture suggests that this bacterial association is a unique microbial community, in which development of acidophilic hydrocarbon-oxidizing bacteria is mediated by a localized pH decrease in the sulfur blocks resulting from elemental sulfur oxidation due to massive development of chemolithotrophic sulfur-oxidizing bacteria.  相似文献   
97.

Background

Antiarrhythmic action of flecainide is based on sodium channel blockade. Beta1-adrenoceptor (β1AR) activation induces sodium channel inhibition, too. The aim of the present study was to evaluate the impact of different β1AR genotypes on antiarrhythmic action of flecainide in patients with structural heart disease and atrial fibrillation.

Methodology/Principal Findings

In 145 subjects, 87 with atrial fibrillation, genotyping was performed to identify the individual β1AR Arg389Gly and Ser49Gly polymorphism. Resting heart rate during atrial fibrillation and success of flecainide-induced cardioversion were correlated with β1AR genotype. The overall cardioversion rate with flecainide was 39%. The Arg389Arg genotype was associated with the highest cardioversion rate (55.5%; OR 3.30; 95% CI; 1.34–8.13; p = 0.003) compared to patients with Arg389Gly (29.5%; OR 0.44; 95% CI; 0.18–1.06; p = 0.066) and Gly389Gly (14%; OR 0.24; 95% CI 0.03–2.07; p = 0.17) variants. The single Ser49Gly polymorphism did not influence the conversion rate. In combination, patients with Arg389Gly-Ser49Gly genotype displayed the lowest conversion rate with 20.8% (OR 0.31; 95% CI; 0.10–0.93; p = 0.03). In patients with Arg389Arg variants the heart rate during atrial fibrillation was significantly higher (110±2.7 bpm; p = 0.03 vs. other variants) compared to Arg389Gly (104.8±2.4 bpm) and Gly389Gly (96.9±5.8 bpm) carriers. The Arg389Gly-Ser49Gly genotype was more common in patients with atrial fibrillation compared to patients without atrial fibrillation (27.6% vs. 5.2%; HR 6.98; 95% CI; 1.99–24.46; p<0.001).

Conclusions

The β1AR Arg389Arg genotype is associated with increased flecainide potency and higher heart rate during atrial fibrillation. The Arg389Gly-Ser49Gly genotype might be of predictive value for atrial fibrillation.  相似文献   
98.
Detecting local adaptation and its spatial scale is one of the most important questions of evolutionary biology. However, recognition of the effect of local selection can be challenging when there is considerable environmental variation across the distance at the whole species range. We analyzed patterns of local adaptation in emmer wheat, Triticum dicoccoides, at two spatial scales, small (inter-population distance less than one km) and large (inter-population distance more than 50 km) using several approaches. Plants originating from four distinct habitats at two geographic scales (cold edge, arid edge and two topographically dissimilar core locations) were reciprocally transplanted and their success over time was measured as 1) lifetime fitness in a year of planting, and 2) population growth four years after planting. In addition, we analyzed molecular (SSR) and quantitative trait variation and calculated the QST/FST ratio. No home advantage was detected at the small spatial scale. At the large spatial scale, home advantage was detected for the core population and the cold edge population in the year of introduction via measuring life-time plant performance. However, superior performance of the arid edge population in its own environment was evident only after several generations via measuring experimental population growth rate through genotyping with SSRs allowing counting the number of plants and seeds per introduced genotype per site. These results highlight the importance of multi-generation surveys of population growth rate in local adaptation testing. Despite predominant self-fertilization of T. dicoccoides and the associated high degree of structuring of genetic variation, the results of the QST - FST comparison were in general agreement with the pattern of local adaptation at the two spatial scales detected by reciprocal transplanting.  相似文献   
99.
Inadequate persistence of tumor‐infiltrating natural killer (NK) cells is associated with poor prognosis in cancer patients. The solid tumor microenvironment is characterized by the presence of immunosuppressive factors, including prostaglandin E2 (PGE2), that limit NK cell persistence. Here, we investigate if the modulation of the cytokine environment in lung cancer with IL‐2 or IL‐15 renders NK cells resistant to suppression by PGE2. Analyzing Cancer Genome Atlas (TCGA) data, we found that high NK cell gene signatures correlate with significantly improved overall survival in patients with high levels of the prostaglandin E synthase (PTGES). In vitro, IL‐15, in contrast to IL‐2, enriches for CD25+/CD54+ NK cells with superior mTOR activity and increased expression of the cAMP hydrolyzing enzyme phosphodiesterase 4A (PDE4A). Consequently, this distinct population of NK cells maintains their function in the presence of PGE2 and shows an increased ability to infiltrate lung adenocarcinoma tumors in vitro and in vivo. Thus, strategies to enrich CD25+/CD54+ NK cells for adoptive cell therapy should be considered.  相似文献   
100.
Hypoxia sensing is the generic term for pO2-sensing in humans and other higher organisms. These cellular responses to pO2 are largely controlled by enzymes that belong to the Fe(II) α-ketoglutarate (αKG) dependent dioxygenase superfamily, including the human enzyme called the factor inhibiting HIF (FIH-1), which couples O2-activation to the hydroxylation of the hypoxia inducible factor α (HIFα). Uncoupled O2-activation by human FIH-1 was studied by exposing the resting form of FIH-1 (αKG + Fe)FIH-1, to air in the absence of HIFα. Uncoupling lead to two distinct enzyme oxidations, one a purple chromophore (λmax = 583 nm) arising from enzyme auto-hydroxylation of Trp296, forming an Fe(III)-O-Trp296 chromophore [Y.-H. Chen, L.M. Comeaux, S.J. Eyles, M.J. Knapp, Chem. Commun. (2008), doi:10.1039/B809099H]; the other a yellow chromophore due to Fe(III) in the active site, which under some conditions also contained variable levels of an oxygenated surface residue (oxo)Met275. The kinetics of purple FIH-1 formation were independent of Fe(II) and αKG concentrations, however, product yield was saturable with increasing [αKG] and required excess Fe(II). Yellow FIH-1 was formed from (succinate + Fe)FIH-1, or by glycerol addition to (αKG + Fe)FIH-1, suggesting that glycerol could intercept the active oxidant from the FIH-1 active site and prevent hydroxylation. Both purple and yellow FIH-1 contained high-spin, rhombic Fe(III) centers, as shown by low temperature EPR. XAS indicated distorted octahedral Fe(III) geometries, with subtle differences in inner-shell ligands for yellow and purple FIH-1. EPR of Co(II)-substituted FIH-1 (αKG + Co)FIH-1, indicated a mixture of 5-coordinate and 6-coordinate enzyme forms, suggesting that resting FIH-1 can readily undergo uncoupled O2-activation by loss of an H2O ligand from the metal center.  相似文献   
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