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Journal of Plant Growth Regulation - This study investigated the physiological, molecular, and anatomical responses of soybean to the long-time utilization of nitric oxide (NO; 0 and...  相似文献   
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The relationships between the structural and energetic domains of lentil seedling amine oxidase (LSAO) were investigated using modifiers that target the active site and the carbohydrate moiety of the enzyme. An irreversible inhibitor, aminoguanidine, specifically modified the active site of the lentil enzyme, whereas sodium metaperiodate cleaves carbohydrate moieties covalently bound to the native enzyme. Differential scanning calorimetry (DSC) measurements were made on the modified LSAOs. Deconvolution of the reversible thermal DSC profiles of the modified enzyme gave three subpeaks (energetic domains), each of which was assigned to one of the three structural domains of the native protein. Our results led us to conclude that deglycosylation of LSAO has no effect on thermal stability, whereas binding of the inhibitor imparts more stability to the enzyme.  相似文献   
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BackgroundStereotactic radiosurgery (SRS) method has been considered the first-line treatment option to treat patients involved with pre-optic nerve tumors. However, studies have shown that using fractionated SRS, normal tissue sparing and tumor dose can be strongly increased simultaneously. Our main goal was to illustrate the effects of fractionated SRS approach in optic nerve tumor treatment and its adjacent sensitive structures.Materials and methods19 patients involved in optic nerve tumor with clinical symptoms of vision loss were treated with Gamma Knife radiosurgery in three sessions with 12 hours intervals between them. The prescribed dose was about 6.0 ± 1.2 Gy. Patient-related parameters including pre-treatment and after-treatment tumor size, visual acuity and visual field were evaluated using the Snell chart and MRI imaging. Patients were followed for about 14 months.ResultThe overall result showed vision improvement for patients with low and moderate visual loss. However, there was no significant improvement in patients with severe visual loss. Relative improvement was observed in blind patients, although poorly. There was no evidence of growth, recurrence, or new tumor after treatment in patients.ConclusionFractionated gamma knife radiosurgery offers a safe and effective alternative for benign lesions adjacent to the optic nerve.  相似文献   
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This work discusses surface modification of cellulose paper specimens for compatibility with nitrogen and sulfur co-doped carbon dots (NSCDs) for lead ion sensing. The interaction of carbon dots (CDs) and cellulose fibers was investigated using silane or chitosan-modified cellulose papers. It was found that modified papers could reduce undesirable redistribution of CDs, during paper drying. Also, only chitosan-modified filter paper was suitable for the successful immobilization of NSCDs. The effect of paper type, chitosan amount, pH, and NSCDs concentration was also studied, and a Whatman No. 42 filter paper modified with chitosan (1% w/v), pH 8.0, and an NSCD concentration of 2.5 g L−1 being selected for further studies. The sensor exhibited high selectivity for lead(II) compared with other metal ions because lead(II) resulted in the most significant changes in the emitted light intensity. Variations in NSCDs fluorescence were measured using a fluorescence imaging system. The NSCDs-paper sensor showed a linear relationship between mean fluorescence intensity and lead(II) in the concentration range of 5.00–1.25 × 102 μmol L−1 with a correlation coefficient (R2) of 0.9988 and a detection limit of 4.50 μmol L−1. The suggested method showed satisfying results for lead(II) determination in different samples as a fast and low-cost approach with on-site application.  相似文献   
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ObjectiveAcute liver failure is usually associated with inflammation and oxidation of hepatocytes and has high mortality and resource costs. Mesenchymal stem cell (MSCs) has occasionally been reported to have no beneficial effect due to poor transplantation and the survival of implanted cells. Recent studies showed that embryonic stem cell (ESC)‐derived MSCs are an alternative for regenerative medicine. On the other hand, graphene‐based nanostructures have proven useful in biomedicine. In this study, we investigated whether magnetic graphene oxide (MGO) improved the effects of ESC‐MSC conditioned medium (CM) on protecting hepatocytes and stimulating the regeneration of damaged liver cells.Materials and methodsTo provide a rat model of acute liver failure, male rats were injected intraperitoneally with carbon tetrachloride (CCl4). The rats were randomly divided into six groups, namely control, sham, CCl4, ESC‐MSC‐CM, MGO and ESC‐MSC‐CM + MGO. In the experimental groups, the rats received, depending on the group, 2 ml/kg body weight CCl4 and either ESC‐MSC‐CM with 5 × 106 MSCs or 300 μg/kg body weight MGO or both. Symptoms of acute liver failure appeared 4 days after the injection. All groups were compared and analysed both histologically and biochemically 4 days after the injection. Finally, the results of ESC‐MSC‐CM and MSC‐CM were compared.ResultsThe results indicated that the use of MGO enhanced the effect of ESC‐MSC‐CM on reducing necrosis, inflammation, aspartate transaminase, alanine aminotransferase and alkaline phosphatase in the CCl4‐induced liver failure of the rat model. Also, the expression of vascular endothelial growth factor and matrix metalloproteinase‐9 (MMP‐9) was significantly upregulated after treatment with MGO. Also, the results showed that the ESC‐MSC‐CM has more efficient effective compared to MSC‐CM.ConclusionMagnetic graphene oxide improved the hepatoprotective effects of ESC‐MSC‐CM on acute liver damage, probably by suppressing necrosis, apoptosis and inflammation of hepatocytes.  相似文献   
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Female genital mutilation (FGM) is still a common practice in many countries in Africa and the Middle East. Understanding the determinants of FGM can lead to more active interventions to prevent this harmful practice. The goal of this study is to explore factors associated with FGM behavior among Iranian mothers and their daughters. Based on Ajzen’s theory of planned behavior, we examined the predictive value of attitudes, subjective norms, perceived behavioral control and several socio-demographic variables in relation to mothers’ intentions to mutilate their daughters. A paper-and-pencil survey was conducted among 300 mothers (mean age = 33.20, SD = 9.09) who had at least one daughter and who lived in Ravansar, a county in Kermanshah Province in Iran. Structural equation modeling was used to investigate the relationships among the study variables. Our results indicate that attitude is the strongest predictor of mothers’ intentions to allow their daughters to undergo FGM, followed by subjective norms. Compared to younger mothers, older mothers have more positive attitudes toward FGM, perceive themselves as having more control over their behavior and demonstrate a greater intention to allow their daughter to undergo FGM. Furthermore, we found that less educated mothers and mothers living in rural areas had more positive attitudes toward FGM and feel more social pressure to allow FGM. The model accounts for 93 percent of the variance in the mothers’ intentions to allow their daughters to undergo FGM. Intervention programs that want to decrease FGM might focus primarily on converting mothers’ neutral or positive feelings toward FGM into negative attitudes and on alleviating the perceived social pressure to mutilate one’s daughter. Based on our findings, we provide recommendations about how to curtail mothers’ intentions to allow their daughters to undergo FGM.  相似文献   
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Seven ab initio web-based gene prediction programs (i.e., AUGUSTUS, BGF, Fgenesh, Fgenesh+, GeneID, Genemark.hmm, and HMMgene) were assessed to compare their prediction accuracy using protein-coding sequences of bread wheat. At both nucleotide and exon levels, Fgenesh+ was deduced as the superior program and BGF followed by Fgenesh were resided in the next positions, respectively. Conversely, at gene level, Fgenesh with the value of predicting more than 75% of all the genes precisely, concluded as the best ones. It was also found out that programs such as Fgenesh+, BGF, and Fgenesh, because of harboring the highest percentage of correct predictive exons appear to be much more applicable in achieving more trustworthy results, while using both GeneID and HMMgene the percentage of false negatives would be expected to enhance. Regarding initial exon, overall, the frequency of accurate recognition of 3′ boundary was significantly higher than that of 5′ and the reverse was true if terminal exon is taken into account. Lastly, HMMgene and Genemark.hmm, overall, presented independent tendency against GC content, while the others appear to be slightly more sensitive if GC-poor sequences are employed. Our results, overall, exhibited that to make adequate opportunity in acquiring remarkable results, gene finders still need additional improvements.  相似文献   
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