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Bulletin of Experimental Biology and Medicine - A model of moderate hyperhomocysteinemia associated with mechanical injury of the musculoskeletal system was developed and experimentally...  相似文献   
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The assessment of the harmfulness of moulding and core sands is mainly based on investigations of compositions of gases emitted by liquid casting alloys during the mould pouring. The results of investigations of moulding sands obtained under industrial conditions are presented in this paper. A unique research stand was designed and built for this aim. It allowed us to determine emissions of gases at individual stages of casting a mass up to 50 kg. This approach enables simulation of foundry conditions. Moulding sands bound by organic binders (phenol-formaldehyde; furan), inorganic binders and green sand, were subjected to investigations. The composition of gases that evolved during the individual stages, pouring, cooling and knocking out, was tested each time, and the contents of Polycyclic Aromatic Hydrocarbons (PAHs) and benzene, toluene, ethylbenzene, and xylenes (BETX) were analysed. Investigations indicated that the emission of gases from sands with inorganic binders is negligible when compared with the emission of gases from sands with organic binders. The emission of gases from green sand is placed in the middle of the scale. As an example: the sand with furan resin emitted 84 mg of BTEX (in recalculation for 1 kg of sand) while from sands with inorganic binders there was a maximum of 2.2 mg (for 1 kg of sand). In the case of sands with inorganic binders, MI and MC sands indicated comparable and very low emissions of gases from the PAHs group, at the level of 0.018 mg and 0.019 mg for 1 kg of sand, respectively. The higher emission of PAHs from MG sand is the result of its different way of hardening (a binder was of an organic character) than of sands MI and MC.  相似文献   
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PurposeMany studies indicate an inverse relationship between stromal-derived factor-1 alpha (SDF-1 alpha), a chemokine, and coronary risk factors. Moreover, SDF-1 alpha is crucial in neoangiogenesis and in the mobilization and homing of endothelial progenitor cells to the ischemic coronary vessels. Numerous studies indicate that circulating sex hormones are associated with atherogenesis during male aging. The aim of this study was therefore to determine whether there exists a relationship between SDF-1 alpha and endogenous sex hormones in aging men with stable coronary artery disease (CAD).Material and methodsPlasma concentrations of SDF-1 alpha, testosterone (T), estradiol (E2), and sex hormone binding globulin (SHBG) were measured and the E2/T ratio was calculated in a cross-sectional study of 82 men over 50 years of age with stable CAD.ResultsSDF-1 alpha was positively and significantly correlated with T (r = 0.233; p = 0.036) and with SHBG (r = 0.312; p = 0.004). There was a significant inverse correlation between SDF-1 alpha and the E2/T ratio (r = -0.463; p < 0.001). After adjustment for age, body mass index and smoking status, SHBG and E2/T ratio were the only factors associated with SDF-1 alpha.ConclusionsT and SHBG (directly) and the E2/T ratio (inversely) may be involved in the etiopathogenesis of CAD through their relationships to SDF-1 alpha.  相似文献   
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