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排序方式: 共有289条查询结果,搜索用时 15 毫秒
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Karadag  Abdullah  Ozen  Ata  Ozkurt  Mete  Can  Cavit  Bozgeyik  Ibrahim  Kabadere  Selda  Uyar  Ruhi 《Molecular biology reports》2021,48(7):5531-5539
Molecular Biology Reports - Herein, we identified miRNA signatures that were able to differentiate malignant prostate cancer from benign prostate hyperplasia and revealed the therapeutic potential...  相似文献   
3.
A new series of 6, 7-dihydroxy-3-(methylphenyl) chromenones, including three new derivatives, i.e. 6,7-dihydroxy-3-(2-methylphenyl)-2H-chromen-2-one (OPC); 6,7-dihydroxy-3-(3-methylphenyl)-2H-chromen-2-one (MPC); 6,7-dihydroxy-3-(4-methylphenyl)-2H-chromen-2-one (PPC) and one previously described, namely 6,7-dihydroxy-3-phenyl-2H-chromen-2-one (DPC), were synthesized. These compounds were investigated as inhibitors of human carbonic anhydrase I (hCA-I) and human carbonic anhydrase II (hCA-II) which had been purified from human erythrocytes on an affinity gel comprised of L-tyrosine-sulfonamide-Sepharose 4B.  相似文献   
4.
The enzyme carbonic anhydrase (E.C. 4.2.1.1) has a stimulatory effect on glaucoma, an eye disease that has a risk to dogs, which are models for the human eye disease, that is similar to that in humans.

In this study, some sulfonamide derivatives, 2-(3-cyclohexene-1-carbamido)-1,3,4-thiadiazole-5-sulfonamide (CCTS), 4-(3-cyclohexene-1-carbamido) methyl-benzenesulfonamide (CCBS), 2-(9-octadecenoylamido)-1,3,4-thiadiazole-5-sulfonamide (ODTS), 2-(4,7,10-trioxa-tetradecanoylamido)-1,3,4-thiadiazole-5-sulfonamide (TDTS), and 2-(8-methoxycoumarine-3-carbamido)-1,3,4-thiadiazole-5-sulfonamide (MCTS), as well as some anionic compounds (perchlorate and chloride) and existing medicines (dorzolamide-HCl, gentamicine sulphate, tropicamide, and procaine-HCl) were assayed for their inhibition of dog carbonic anhydrase (dCA), which was purified from erythrocytes on an affinity gel of L-tyrosine-sulfonamide-Sepharose 4B. ODTS showed the highest potency amongst the synthetic compounds with IC50 value 1.18 × 10? 5 M. Amongst the medicines tested, only dorzolamide showed inhibition with IC50 value 5.05 × 10? 4 M. Procaine and tropicamide actually showed an activatory effect, whereas gentamicine sulfate had no significant effect. The inhibitory effects of anionic compounds such as perchlorate and chloride were also investigated; whereas perchlorate showed inhibition, chloride did not.  相似文献   
5.
The Firmicutes represent a major component of the intestinal microflora. The intestinal Firmicutes are a large, diverse group of organisms, many of which are poorly characterized due to their anaerobic growth requirements. Although most Firmicutes are Gram positive, members of the class Negativicutes, including the genus Veillonella, stain Gram negative. Veillonella are among the most abundant organisms of the oral and intestinal microflora of animals and humans, in spite of being strict anaerobes. In this work, the genomes of 24 Negativicutes, including eight Veillonella spp., are compared to 20 other Firmicutes genomes; a further 101 prokaryotic genomes were included, covering 26 phyla. Thus a total of 145 prokaryotic genomes were analyzed by various methods to investigate the apparent conflict of the Veillonella Gram stain and their taxonomic position within the Firmicutes. Comparison of the genome sequences confirms that the Negativicutes are distantly related to Clostridium spp., based on 16S rRNA, complete genomic DNA sequences, and a consensus tree based on conserved proteins. The genus Veillonella is relatively homogeneous: inter-genus pair-wise comparison identifies at least 1,350 shared proteins, although less than half of these are found in any given Clostridium genome. Only 27 proteins are found conserved in all analyzed prokaryote genomes. Veillonella has distinct metabolic properties, and significant similarities to genomes of Proteobacteria are not detected, with the exception of a shared LPS biosynthesis pathway. The clade within the class Negativicutes to which the genus Veillonella belongs exhibits unique properties, most of which are in common with Gram-positives and some with Gram negatives. They are only distantly related to Clostridia, but are even less closely related to Gram-negative species. Though the Negativicutes stain Gram-negative and possess two membranes, the genome and proteome analysis presented here confirm their place within the (mainly) Gram positive phylum of the Firmicutes. Further studies are required to unveil the evolutionary history of the Veillonella and other Negativicutes.  相似文献   
6.
Protein tyrosine kinases (PTKs) play an important role in T cell development and activation. In vitro and in vivo defects, resulting in variable deficiencies in thymic development and in T cell antigen receptor (TCR) signal transduction, in PTKs have been shown. ZAP70, one of those PTKs, is a 70-kDa tyrosine phosphoprotein and associates with the ζ chain and undergoes tyrosine phosphorylation following TCR stimulation. It is expressed in T and natural killer (NK) cells. Several mutations were shown to lead to an autosomal recessive form of severe combined immunodeficiency disease (SCID).  相似文献   
7.
ABSTRACT

Circadian disruption has been linked with immune-related morbidities including autoimmune diseases. PERIOD3 (PER3) clock gene is a key player in the mammalian circadian system. This study evaluated the possible association of PER3 rs2797685 (G/A) polymorphism and susceptibility of autoimmune thyroid diseases (AITD) and assessed if this SNP contributes to disease characteristics and serum levels of interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α). The PER3 rs2797685 (G/A) polymorphism was assessed in 125 patients with AITD [Graves’ disease (GD), 69; Hashimoto’s thyroiditis (HT), 56] and 115 unrelated healthy controls. Subjects carrying at least one variant allele of PER3 rs2797685 (GA+AA) had increased risk for GD (OR 1.9, 95% CI 1–3.61, p= .05). There were no differences in the frequencies of genotypes and alleles of the PER3 rs2797685 polymorphism between HT patients and control subjects. No association was observed between genotypes of the studied SNP and any of the disease characteristics in GD and HT patients. The GA+AA genotype of PER3 rs2797685 was associated with lower levels of IL-6 in patients with Graves’ disease. There were no differences between genotypes of the studied SNP regarding TNF-α levels in GD, HT or control groups. In conclusion, this study provides the first evidence for a genetic association between GD and the PER3 gene, highlighting the possible relevance of polymorphisms in clock genes in the etiopathogenesis of AITD. However, functional studies to identify the underlying molecular mechanisms of this association are needed to translate these findings to clinical applications.  相似文献   
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In this study, HPLC-MS and ICP-MS methods were used for the determination of histidine and nickel in Morus L., Robinia pseudoacacia L., and Populus nigra L. leaves taken from industrial areas including Gaziantep and Bursa cities. In the determination of histidine by HPLC-MS, all of the system parameters such as flow rate of mobile phase, fragmentor potential, injection volume and column temperature were optimized and found to be 0.2 mL min?1, 70 V, 15 µL, and 20°C, respectively. Under the optimum conditions, histidine was extracted from plant sample by distilled water at 90°C for 30 min. Concentrations of histidine as mg kg?1 were found to be between 2–9 for Morus L., 6–13 for Robinia pseudoacacia L., and 2–10 for Populus nigra L. Concentrations of nickel were in the ranges of 5–10 mg kg?1 for Morus L., 3–10 mg kg?1 for Robinia pseudoacacia L., and 0.6–4 mg kg?1 for Populus nigra L. A significant linear correlation (r = 0.78) between histidine and Ni was observed for Populus nigra L., whereas insignificant linear correlation for Robinia pseudoacacia L. (r = 0.22) were seen. Limits of detection (LOD) and quantitation (LOQ) were found to be 0.025 mg Ni L?1 and 0.075 mg Ni L?1, respectively.  相似文献   
10.

Cysteine (Cys) is the first identified molecule in plant metabolism which includes both sulfur and nitrogen. It can be synthesized in three cellular compartments, containing chloroplast, cytoplasm and mitochondrion. The final step of cysteine biosynthesis is catalyzed by the O-acetylserine(thiol)lyase enzyme (OASTL, E.C. 4.2.99). In the present study, seven members of the OASTL gene family in the sorghum (Sorghum bicolor) genome were identified at a genome-wide scale and comparative bioinformatics analyses were performed between sorghum and Arabidopsis OASTLs. In all OASTL proteins, a pyridoxal-phosphate dependent domain structure (PALP, PF00291) was identified. The gene ontology annotations also revealed that all sorghum OASTL genes have KOG1252 (Cystathionine beta-synthase and related enzyme) and K01738 (cysteine synthase A) activities. In promotor sequences of OASTL genes, diverse cis-acting elements were found, including hormone and light responsiveness, abiotic stress responsiveness, and tissue-specific ones (meristem and endosperm). Sorghum OASTL genes demonstrated medium or high level expressions in anatomical parts and developmental stages based on the digital expression data. Expression of OASTL genes were also analyzed under cadmium (Cd) stress in sorghum by Real Time-quantitative PCR (RT-qPCR). The results exclusively showed that OASTL A1-2 gene was 1.12 fold up-regulated in roots, whereas cysteine synthase 26 was 2.25 fold down-regulated in leaves. The predicted 3D structure of OASTLs indicated some structural diversities as well as variations in the secondary structures.

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