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41.
Tatiana Safronova Andrey Kiselev Irina Selezneva Tatiana Shatalova Yulia Lukina Yaroslav Filippov Otabek Toshev Snezhana Tikhonova Olga Antonova Alexander Knotko 《Materials》2022,15(9)
Ceramic samples based on β-calcium pyrophosphate β-Ca2P2O7 were prepared from powders of γ-calcium pyrophosphate γ-Ca2P2O7 with preset molar ratios Ca/P = 1, 0.975 and 0.95 using firing at 900, 1000, and 1100 °C. Calcium lactate pentahydrate Ca(C3H5O3)2⋅5H2O and monocalcium phosphate monohydrate Ca(H2PO4)2⋅H2O were treated in an aqua medium in mechanical activation conditions to prepare powder mixtures with preset molar ratios Ca/P containing calcium hydrophosphates with Ca/P = 1 (precursors of calcium pyrophosphate Ca2P2O7). These powder mixtures containing calcium hydrophosphates with Ca/P = 1 and non-reacted starting salts were heat-treated at 600 °C after drying and disaggregation in acetone. Phase composition of all powder mixtures after heat treatment at 600 °C was presented by γ-calcium pyrophosphate γ-Ca2P2O7 according to the XRD data. The addition of more excess of monocalcium phosphate monohydrate Ca(H2PO4)2·H2O (with appropriate molar ratio of Ca/P = 1) to the mixture of starting components resulted in lower dimensions of γ-calcium pyrophosphate (γ-Ca2P2O7) individual particles. The grain size of ceramics increased both with the growth in firing temperature and with decreasing molar ratio Ca/P of powder mixtures. Calcium polyphosphate (t melt = 984 °C), formed from monocalcium phosphate monohydrate Ca(H2PO4)2⋅H2O, acted similar to a liquid phase sintering additive. It was confirmed by tests in vitro that prepared ceramic materials with preset molar ratios Ca/P = 1, 0.975, and 0.95 and phase composition presented by β-calcium pyrophosphate β-Ca2P2O7 were biocompatible and could maintain bone cells proliferation. 相似文献
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Anton R. Kiselev M.D. D.Sc. Vladimir I. Gridnev M.D. D.Sc. Mikhail D. Prokhorov D.Sc. Anatoly S. Karavaev Ph.D. Olga M. Posnenkova M.D. Ph.D. Vladimir I. Ponomarenko D.Sc. Boris P. Bezruchko D.Sc. Vladimir A. Shvartz M.D. Ph.D. 《Annals of noninvasive electrocardiology》2012,17(3):204-213
Background: Synchronization between 0.1‐Hz rhythms in cardiovascular system is deteriorated at acute myocardial infarction (AMI) leading to a disruption of natural functional couplings within the system of autonomic regulation. Objective: This study evaluates the prognostic value of autonomic regulation indices for the 5‐year risk of fatal and nonfatal cardiovascular events in patients after AMI. Methods and Results: We studied 125 patients (53 [42%] female) after AMI aged between 30 and 83 years. The period of observation was 5 years with checkpoints at the first week after AMI and after each year after AMI. We compared the prognostic value of established clinical characteristics and degree S of synchronization between 0.1‐Hz rhythms in heart rate and microcirculation for evaluation of the 5‐year risk of mortality and recurrent myocardial infarction (MI) in patients after AMI. Acute heart failure Killip 2–4 at AMI and S < 20% at the first week after AMI were identified as the most important factors for evaluation of the risk of 5‐year mortality in patients after AMI (χ2= 14.2, P = 0.003). Sensitivity and specificity of low S (<20%) at the first week after AMI were 76% and 43%, respectively. For evaluation of the 5‐year risk of recurrent MI index S had no advantage over established clinical characteristics. Conclusion: The value of S below 20% in patients with AMI is a sensitive marker of high risk of mortality during the subsequent five years. It is characterized by better prognostic value than most of established clinical characteristics. 相似文献
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Matthew J. McQueen Peter A. Kavsak Liqin Xu Olga Shestakovska Salim Yusuf 《Clinical biochemistry》2013,46(1-2):5-9
ObjectivesPrevious work on high-sensitivity troponin I (hs-cTnI) has demonstrated that it may identify patients with stable cardiovascular disease (CVD) at risk for future myocardial infarction (MI). In this study, we assessed if hs-cTnT concentrations could also identify those stable CVD patients at high risk for future MI and other ischemic cardiac outcomes.Methodshs-cTnT (lot:153-401) was measured in specimens obtained at randomisation in the Heart Outcomes Prevention Evaluation (HOPE) study (n = 2941 stable CVD patients, 4.5 years follow-up). The primary outcome for the HOPE study (MI, stroke, or cardiovascular death) was used to identify cutoffs by receiver operating characteristic (ROC) curve analysis and was used in conjunction with the 95th and 99th percentile upper limits to construct different concentration ranges, which were assessed using log-rank tests and multivariable Cox proportional hazard models. These different concentration ranges were then assessed for the components of the primary outcome and for heart failure (HF).ResultsThe ROC derived hs-cTnT cutoff was 8 ng/L for the primary outcome. Subjects with hs-cTnT either below (8 to < 14 ng/L) or slightly above the published 99th from a healthy population (14 to 21 ng/L) had similar probability for the primary outcome. Those with hs-cTnT concentrations > 31 ng/L had the highest probability and greatest risk for future MI, HF, and cardiovascular death as compared to those with hs-cTnT concentrations < 8 ng/L.ConclusionIn patients with stable CVD disease hs-cTnT measurement identifies those at risk for MI as well as HF and cardiovascular death. 相似文献
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Katerina Kotzampassi Olga Vasilaki Christina Stefanidou Vasilis Grosomanidis 《Asian journal of endoscopic surgery》2013,6(3):214-216
Here we present the case of Candida albicans colonization on an intragastric balloon placed for weight loss. A 52‐year‐old obese woman achieved a BMI reduction of 10.9 kg/m2 within 7 months as a result of a BioEnterics Intragastric Balloon and a well‐balanced, low‐calorie diet. During endoscopy for balloon removal, the balloon, which was well impacted in the gastric fundus, was found to be lime green in color with clusters of cone‐shaped cultures on its surface. Microbiology assessment revealed the presence of Candida albicans, although the patient was totally asymptomatic. 相似文献