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In this work, a new filter, used to prevent atmospherical pollution, has been developed. Spherical amorphous shaped silicates (such as KC-Siliperl AF 125 and Aluminium silicate 596 FA) were coated with different materials which were prepared from the hydrolysis-condensation products of organically modified silanes and metal alkoxides. The adsorption capacities of such silicates for different solvents; ethylacetate, toluene, n-hexane and cyclohexanone were investigated. It was found that KC-Siliperl AF 125 coated with IMEO (a commercial silane) adsorbed all the solvents better than Aluminium silicate 596 FA, and ethylacetate was adsorbed more than the other solvents.  相似文献   
97.
The ability of Calabrian pine bark wastes (Pinus brutia Ten) for the removal of Fe(II) ions from aqueous solution at different concentrations and temperatures at a fixed pH was investigated. While the amounts of Fe(II) ions adsorbed onto the bark increased with increasing concentration, it increased slightly with increasing the temperature. Kinetics studies showed that adsorption process followed the first-order kinetic model as well as intra-particle diffusion kinetics. Adsorption isotherm followed both Langmuir and Freundlich models. And it was determined that the adsorption was favorable from a dimensionless factor, R(L). Furthermore, the thermodynamic parameters demonstrated that the removal of Fe(II) by the bark was a physical process.  相似文献   
98.
Macrolides, a class of antimicrobials isolated from Streptomycetes more than 50 years ago, are used extensively to treat sinopulmonary infections in humans. In addition, a growing body of experimental and clinical evidence indicates that long-term (years), low (sub-antimicrobial)-dose 14- and 15-membered ring macrolide antibiotics, such as erythromycin, clarithromycin, roxithromycin and azithromycin, express immunomodulatory and tissue reparative effects that are distinct from their anti-infective properties. These salutary effects are operative in various lung disorders, including diffuse panbronchiolitis, cystic fibrosis, persistent chronic rhinosinusitis, nasal polyposis, bronchiectasis, asthma and cryptogenic organizing pneumonia.The purpose of this overview is to outline the immunomodulatory effects of macrolide antibiotics in patients with asthma.  相似文献   
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Weismann-Netter syndrome (WNS), a rare condition, is characterized by an anterior curvature of the bones of the lower limbs, usually bilateral and symmetrical. It was first described in 1954 by Weismann-Netter and Stuhl. We report a 2-year-old girl with typical findings of WNS who was misdiagnosed as having rickets. Our purpose is to draw attention to the WNS in the differential diagnosis of skeletal dysplasias. We think that the true incidence of WNS is probably higher than previously reported; therefore, we would like to emphasize that WNS should be considered in patients who have bowed lower extremities and have been diagnosed as having syphilis or healed rickets.  相似文献   
100.
The Genotoxic Effect of the New Acaricide Etoxazole   总被引:2,自引:1,他引:1  
Etoxazole is a member of the diphenyl oxazoline class of insecticide, which was newly developed for use on pome fruits, cotton and strawberries as an acaricide. In the present study, genotoxic effects of acaricide etoxazole (ETX) (miticide/ovicide) were investigated using chromosome aberration (CA) test, sister chromatid exchange (SCE) test, and micronucleus test in human lymphocytes. ETX induced the CAs at all concentrations (5, 10, and 20 g/ml) for 24 h and also induced the CA at the highest concentration (20 g/ml) for 48 h only. The inducing the CAs for 48 h treatment period was dose-dependent. In addition, it induced the SCE at all concentrations and treatment periods in a dose-dependent manner as well. Although ETX decreased the mitotic index (MI) at all concentrations and treatment periods dose-dependently, it did not decrease the replication index (RI) when compared to the negative and solvent controls. In addition, ETX induced the micronucleus at all concentrations except 5 g/ml for 48 h. This inducing was dose-dependent as well. It can be concluded that ETX has a potential genotoxic effects in cultured human peripheral lymphocytes.  相似文献   
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