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AIM: To study effects of glomerular filtration rate (GFR) reduction on endothelial function in patients at early stages of chronic renal kidney (CKD). MATERIAL AND METHODS: Endothelial function of 101 patients with CKD of stage I-III was examined using reactive hyperemia test, dopplerography of skin vessels with ionophoresis of acetylcholin and nitroglycerin, lipidogram parameters, homocistein and annexin A5 levels, intima-media complex thickness of the common carotid artery, echocardiography findings. RESULTS: Cardiovascular complications risk factors were found in all the patients: increased body mass index, arterial hypertension, dyslipoproteinemia, hyperhomocysteinemia. Reduced GFR (under 90 ml/min) is an independent factor of atherosclerosis risk. CONCLUSION: GFR reduction corresponding to CRD of stage II is accompanied with enhancement of apoptosis and development of vasomotor endothelial dysfunction that in combination with risk factors contribute to development of a preclinical atherosclerosis phase.  相似文献   
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A study of prostaglandins (PGE2 and PGF2) and cyclic nucleotides (cAMP, cGMP) in the blood and gastric mucosa biopsies was carried out. In peptic ulcer the level of cyclic nucleotides in the blood and gastric mucosa was on an increase. The level of prostaglandins increased in the blood and decreased in the gastric mucosa. A decrease in the level of prostaglandins and cAMP in the blood and gastric mucosa was noted in patients with chronic atrophic histamine refractory gastritis with a simultaneous rise of the cAMP level. It was shown that stable stimulation of cyclic nucleotides resulting in an increase of gastric acid production, might cause ulcer development and exacerbation of disease. In patients with chronic atrophic gastritis changes of prostaglandins and cyclic nucleotides as compared to those in patients with peptic ulcer, were contrary.  相似文献   
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We present images from computed tomography angiography in a 40-year-old female with a calcified pseudo-aneurysm in her left coronary artery, who had previously undergone repair of tetralogy of Fallot.  相似文献   
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Textile materials produced from a high tenacity industrial polyester fiber are most widely used in the mechanical rubber goods industry to reinforce conveyor belts, tire cords, and hoses. Reinforcement of textile rubber undergoes a vulcanization process to adhere the textile materials with the rubber and to enhance the physio-mechanical properties of the product. The vulcanization process has an influence on the textile material being used as a reinforcement. In this work, the effects of aging temperature and time on the high tenacity polyester yarn’s mechanical and surface structural properties were investigated. An experiment was carried out on a pre-activated high tenacity polyester yarn of different linear densities, by aging the yarn specimens under various aging temperatures of 140, 160, 200, and 220 °C for six, twelve, and thirty-five minutes of aging time. The tensile properties and surface structural change in the yarns pre- and post-aging were studied. The investigation illustrates that aging time and temperature influence the surface structure of the fiber, tenacity, and elongation properties of the yarn. Compared to unaged yarn, an almost five times higher percentage of elongation was obtained for the samples aged at 220 °C for 6 min, while the lowest tenacity was obtained for the sample subjected to aging under 220 °C for 35 min.  相似文献   
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