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The electronic absorption spectra of the flavomononucleotide (FMN) in aqueous solution and in glycerine-water solution with change of the dye concentration have been measured. The FMN dimer absorption spectrum, monomer absorption spectrum, dimerization constant K and molar fraction of the monomer were calculated. It was found that FMN dimerization constants in aqueous solution were Ka = 118.0 l/mol and in glycerine Kg = 20.5 l/mol. In the region of the monomer absorption band two dimer absorption bands appear, in accordance with the Kasha molecular exciton theory.  相似文献   
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Kiełtyk  Piotr  Delimat  Anna 《Plant Ecology》2019,220(1):1-12
Plant Ecology - The impact of exotic annual Impatiens glandulifera on invaded European vegetation is ambiguous; there are studies reporting considerable negative as well as weak or even no impact...  相似文献   
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The bicarbonate buffer is considered as the most biorelevant buffer system for the simulation of intestinal conditions. However, its use in dissolution testing of solid oral dosage forms is very limited. The reason for this is the thermodynamic instability of the solution containing hydrogen carbonate ions and carbonic acid. The spontaneous loss of carbon dioxide (CO2) from the solution results in an uncontrolled increase of the pH. In order to maintain the pH on the desired level, either a CO2 loss must be completely avoided or the escaped CO2 has to be replaced by quantitative substitution, i.e. feeding the solution with the respective amount of gas, which re-acidifies the buffer after dissociation. The present work aimed at the development of a device enabling an automatic pH monitoring and regulation of hydrogen carbonate buffers during dissolution tests.  相似文献   
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International Journal of Peptide Research and Therapeutics - The progressive damage of human articular cartilage is associated with loss of integrity of its extracellular matrix components. Their...  相似文献   
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Elevated levels of plasma pentraxin 3 (PTX3), a marker of inflammation, are associated with the risk of developing cardiovascular diseases in the general population, as well as in patients with type 2 diabetes (DM2). In this study, we aimed to determine factors associated with PTX3 serum concentrations in men and women with DM2. The study included 116 consecutive patients (67 men and 49 women) with DM2 from an outpatient diabetic clinic. Men were characterised by lower age and higher uric acid, creatinine and bilirubin concentrations and waist/hip ratio than women. In women, low-density lipoprotein cholesterol (LDL-C) levels were higher than in men. In men, median (interquartile range) values of PTX3 concentration were 4.02 (1.99), and in women they were 4.53 (3.31) ng/ml (NS). In men, PTX3 concentrations correlated with total cholesterol (TC), triglycerides, apolipoprotein (Apo) C3, Apo B48, Glc and creatinine levels. In women, PTX3 correlated significantly with TC and LDL-C and Apo B100. Partial regression analysis revealed that after adjusting for age, PTX3 concentrations in men were significantly associated with TC, LDL-C, triglycerides, creatinine, Apo C3 and Apo B48, while in women they were associated with TC, LDL-C and Apo B100. The results could be of importance in sex-specific prevention of vascular complications in DM2 patients.  相似文献   
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