The features of InAs quantum dots obtained on GaAs(001) single-crystal substrates by ion-beam sputtering were investigated. It has been shown that in the range of ion energies of 150 to 200 eV at a temperature of 500 °C and a beam current of 120 µA InAs quantum dots with average dimensions below 15 nm and a surface density of 10 cm are formed. The technique of controlled doping of InAs/GaAs nanostructures using a SnTe solid-state source was proposed.
View Article and Find Full Text PDFLanthanide complexes exhibit interesting spectroscopic properties yielding many applications as imaging probes, natural chirality amplifiers, and therapeutic agents. However, many properties are not fully understood yet. Therefore, we applied magnetic circular dichroism (MCD) spectroscopy, which provides enhanced information about the underlying electronic structure to a series of lanthanide compounds.
View Article and Find Full Text PDFThe intensity of proliferative processes (estimated from Ki-67 expression) and degree oxidative stress (chemiluminescence assay) in biopsy specimens from the terminal portion of the ileal mucosa were studied in patients with Crohn's disease. Crohn's disease is characterized by hyper-regenerative processes in the ileal mucosa. The labeling index (Ki-67 expression) in biopsy specimens from the intact ileal mucosa in patients with the irritable bowel syndrome (reference group) was 10.
View Article and Find Full Text PDFWe studied the effect of simvastatin (24 mg/kg per os for 30 days) on DNA synthesis ((3)H-thymidine autoradiography) and free radical oxidation (chemiluminescent method) in the gastric mucosa of albino mice under normal conditions and in ulcerative process induced by single indometacin administration. Simvastatin treatment activated free radical oxidation, which was seen from enhanced chemiluminescence in the mucosa homogenate (by 1.7-4.
View Article and Find Full Text PDFAdministration of indomethacin (250 mg/kg) to mice was followed by the formation of severe ulcerative and erosive injury to the gastric mucosa, inhibition of DNA synthesis, and development of oxidative stress. Fivefold pretreatment with sedatin (100 microg/kg) decreased the area of indomethacin-induced ulcers and erosions, stimulated DNA synthesis, and reduced the severity of oxidative stress. Non-arginine dermorphin analogue did not stimulate DNA synthesis and had no effect on the degree of oxidative stress.
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