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21.
The nucleotide sequences corresponding to bovine alpha S2- and beta- casein mRNAs have been determined by cDNA analysis. Both sequences appear to be complete at their 5' ends. The nucleotide sequence of alpha S2-casein, when compared with the corresponding cavine A sequence, helps to define the boundaries of a large amino acid repeat (approximately 80 residues) whereas comparisons with the nucleotide sequences of rat gamma- and mouse epsilon-casein mRNAs also reveal extensive sequence similarities. An alignment of these four sequences shows that the divergence of their translated regions has been characterized by the duplication and deletion of discrete segments of sequence that probably correspond to exons. A high degree of nucleotide substitution is also found when the four sequences are compared, except for well-conserved leader-peptide and phosphorylation-site sequences and, to a lesser extent, the 5'-untranslated regions. Similar comparison of the bovine and rat beta-caseins shows that their divergence has involved a high rate of nucleotide substitution but that no major insertions or deletions of sequence have occurred. The several splice sites that have veen defined in the rat beta-casein gene are likely to have been conserved in the bovine. The contrasting evolutionary histories of the alpha- and beta-casein coding sequences correlate with the distinctive functions of these proteins in the casein micelle system in milk.   相似文献   
22.

Background aims

CD1d-restricted invariant natural killer (iNK) T cells are rare regulatory T cells that may contribute to the immune-regulation in allogeneic stem cell transplantation (ASCT). Here, we sought to develop an effective strategy to expand human iNK T cells for use in cell therapy to prevent graft-versus-host disease (GVHD) in ASCT.

Methods

Human iNK T cells were first enriched from peripheral blood mononuclear cells (PBMCs) using magnetic-activated cell sorting separation, then co-cultured with dendritic cells in the presence of agonist glycolipids, alpha-galactosylceramide, for 2 weeks.

Results

The single antigenic stimulation reliably expanded iNK T cells to an average of 2.8?×?107 per 5?×?108 PBMCs in an average purity of 98.8% in 2 weeks (N?=?24). The expanded iNK T cells contained a significantly higher level of CD4+ and central memory phenotype (CD45RA?CD62L+) compared with freshly isolated iNK T cells, and maintained their ability to produce both Th-1 (interferon [IFN]γ and tumor necrosis factor [TNF]α) and Th-2 type cytokines (interleukin [IL]-4, IL-5 and IL-13) upon antigenic stimulation or stimulation with Phorbol 12-myristate 13-acetate/ionomycin. Interestingly, expanded iNK T cells were highly autoreactive and produced a Th-2 polarized cytokine production profile after being co-cultured with dendritic cells alone without exogenous agonist glycolipid antigen. Lastly, expanded iNK T cells suppressed conventional T-cell proliferation and ameliorated xenograft GVHD (hazard ratio, 0.1266; P < 0.0001).

Conclusion

We have demonstrated a feasible approach for obtaining ex vivo expanded, highly enriched human iNK T cells for use in adoptive cell therapy to prevent GVHD in ASCT.  相似文献   
23.
The claim that differences in brain size across primate species has mainly been driven by the demands of sociality (the "social brain" hypothesis) is now widely accepted. Some of the evidence to support this comes from the fact that species that live in large social groups have larger brains, and in particular larger neocortices. Lindenfors and colleagues (BMC Biology 5:20) add significantly to our appreciation of this process by showing that there are striking differences between the two sexes in the social mechanisms and brain units involved. Female sociality (which is more affiliative) is related most closely to neocortex volume, but male sociality (which is more competitive and combative) is more closely related to subcortical units (notably those associated with emotional responses). Thus different brain units have responded to different selection pressures.  相似文献   
24.
The propensity to associate or aggregate is one of the characteristic properties of many nonnative proteins. The aggregation of proteins is responsible for a number of human diseases and is a significant problem in biotechnology. Despite this, little is currently known about the effect of self-association on the structural properties and conformational stability of partially folded protein molecules. G-actin is shown to form equilibrium unfolding intermediate in the vicinity of 1.5 M guanidinium chloride (GdmCl). Refolding from the GdmCl unfolded state is terminated at the stage of formation of the same intermediate state. An analogous form, known as inactivated actin, can be obtained by heat treatment, or at moderate urea concentration, or by the release of Ca(2+). In all cases actin forms specific associates comprising partially folded protein molecules. The structural properties and conformational stability of inactivated actin were studied over a wide range of protein concentrations, and it was established that the process of self-association is rather specific. We have also shown that inactivated actin, being denatured, is characterized by a relatively rigid microenvironment of aromatic residues and exhibits a considerable limitation in the internal mobility of tryptophans. This means that specific self-association can play an important structure-forming role for the partially folded protein molecules.  相似文献   
25.
Polymorphisms c.202G > A of prothrombin F2 gene, c.1691G > A of coagulation factor V F5 gene, c.675delinsG of plasminogen activator 1 gene, and (?5)T > C Kozak gene of thrombocytic receptor were studied in the Russian and Moldavian ethnic groups. We have found no association between these polymorphisms and the risk of ischemic stroke development in both ethnic groups. No association was revealed between the risk of stroke development and various combinations of the single nucleotide polymorphisms examined in the sample of ischemic stroke patients from Russia.  相似文献   
26.
The IVS9-675C > A polymorphism of the HIF-1alpha gene was analyzed in patients with acute ischemic stroke and in a control group. The genotype and allele frequencies proved to significantly differ between the two groups. Allele C and genotypes containing this allele were associated with a higher risk of stroke in the Moscow population.  相似文献   
27.
Polymorphisms c.202G > A of prothrombin F2 gene, c.1691G > A of coagulation factor V F5 gene, c.675delinsG of plasminogen activator1 gene, and (-5)T > C Kozak gene of thrombocytic receptor were studied in the Russian and Moldavian ethnic groups. We have found no association between these polymorphisms and the risk of ischemic stroke development in both ethnic groups. No association was revealed between the risk of stroke development and various combinations of the single nucleotide polymorphisms examined in the sample of ischemic stroke patients from Russia.  相似文献   
28.
The role of variants of the gene encoding arachidonate 5-lipoxygenase-activating protein (ALOX5AP) as possible susceptibility factors for acute stroke were examinated. Two ALOX5AP gene polymorphisms (SG13S114 (rs10507391) and SG13S32 (rs9551963)), which previously had shown association with the risk of ischemic stroke in other populations, were studied. These single nucleotide polymorphisms were analyzed using a sample of acute stroke patients (N = 1320) and a control sample (N = 467). No statistically significant associations were found between acute stroke and the ALOX5AP gene polymorphisms examined.  相似文献   
29.

Background  

Gene expression microarray technology permits the analysis of global gene expression profiles. The amount of sample needed limits the use of small excision biopsies and/or needle biopsies from human or animal tissues. Linear amplification techniques have been developed to increase the amount of sample derived cDNA. These amplified samples can be hybridised on microarrays. However, little information is available whether microarrays based on amplified and unamplified material yield comparable results.  相似文献   
30.
The IVS9-675C > A polymorphism of the HIF-1α gene was analyzed in patients with acute ischemic stroke and in a control group. The genotype and allele frequencies proved to significantly differ between the two groups. Allele C and genotypes containing this allele were associated with a higher risk of stroke in the Moscow population.  相似文献   
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