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One of the existing priorities of the European Union is to search for rational waste management and to keep such waste in the economic cycle, while meeting the highest safety requirements. The paper presents the results of environmental tests of composites based on the polyethylene (rPE) and polypropylene (rPP) matrix and reinforced with cellulose fibres (newsprint, NP). Raw materials were obtained by recycling post-consumer waste such as beverage bottles and newsprint. The composites were tested for their potential use as materials in cladding panels and acoustic barriers. Given that normative documents for these products do not define specific environmental requirements, the composites were tested for the release of dangerous substances, such as anions of inorganic compounds, heavy metals, volatile organic compounds (VOCs), and their impact on the environment. A detailed in-depth analysis of the mechanisms of release of substances (diffusion, dissolution, surface leaching and depletion) from the rPP/NP composite into surface water, groundwater and soil was carried out. In turn, emission of VOCs from the rPE (low-density:high-density (LD:HD)—50:50) and rPE (LD:HD—30:70) composites into indoor air was also carried out. Raw materials in the form of granulates and loose cellulose fibres, used to produce the composites, were also tested for their environmental impact.  相似文献   
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Cobb syndrome (cutaneomeningospinal angiomatosis) is a rare phacomatosis characterized by vascular abnormality of the spinal cord associated with a vascular naevus at the same metamere. We report the case of a newborn with Cobb syndrome, diagnosed by sonography of the spine and later confirmed by MRI. In neonates and young infants with dermatomal cutaneous vascular abnormalities, sonography of the spine should be used as the first imaging modality. © 2012 Wiley Periodicals, Inc. J Clin Ultrasound, 2013  相似文献   
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Oxidized low-density lipoproteins (ox-LDL) have been shown to be strongly atherogenic and immunogenic in experimental animals and in humans. Autoantibodies against ox-LDL and its various epitopes have been detected in sera and in atherosclerotic lesions. LDL oxidation may also lead to generation of oxidized derivatives of cholesterol (eg, 7-ketocholesterol [7-ketoCh]), which are characterized by high levels of cytotoxicity, muta- and carcinogenicity, as well as immunosuppressive effects and probable immunogenic properties. The aim of this study was to quantify autoantibodies to 7-ketoCh in sera from patients after orthotopic heart transplantation (OHT). IgG antibodies were measured in sera from 81 patients after OHT and 73 healthy volunteers using and enzyme-linked immunosorbent assay (ELISA) method. For the antigen we used 7-ketoCh hemisuccinate conjugated to bovine serum albumin. Anti-7-ketoCh antibodies were detected in all examined sera. Their concentrations were significantly higher among OHT patients than the control group, namely, 109.0 ± 109.7 vs 53.5 ± 20.0 U/mL (P < .005). Also, we observed a direct relationship between antibody concentration and time after OHT. Our results showed that the low molecular product of LDL oxidation, 7-ketoCh, was immunogenic possibly playing a role in the progression of atherosclerosis among OHT patients.  相似文献   
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The DNA-dependent RNA polymerase activity and endonucleases in uraemic lymphocyte cells were investigated. It was found that the activity and quantity in three classes of polymerases are remarkably reduced. The reduction in enzyme activity is accompanied by increasing endonuclease activity. The relationship of polymerase enzymes with endonucleases is discussed.  相似文献   
116.
Sympathetic denervation impairs epidermal healing in cutaneous wounds   总被引:3,自引:0,他引:3  
The involvement of peripheral nerves in dermal wound healing, particularly in the inflammatory response has not been extensively studied. Therefore, this study was performed to examine the role of peripheral nerves in the healing of rat skin linear incisions. We report that chemical sympathectomy with 6-hydroxydopamine significantly impaired wound healing as measured on days 7, 11, and 14 postsurgery (by day 14, 48% of the sympathectomized rats were healed in contrast with 84% of the controls; p = 0.0104). In contrast, neonatal capsaicin treatment, which predominantly destroys sensory afferents, had no effect on wound healing ( p > 0.05 on all days). These results support the hypothesis that sympathetic efferents are important for wound healing. Unlike previous research, which showed that peripheral nerves influence ischemic skin flaps, we are the first to demonstrate a role for peripheral nerves in the healing of skin incisions. Because inflammation is an important step in cutaneous wound healing, we propose that a reduction of neurogenic inflammation caused by sympathectomy may explain the impaired wound healing that we observed in our study.  相似文献   
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Studies on the adenosine deaminase (ADA) and aldolase activities in lymphocytes were performed in 67 patients with glomerulonephritis (gn) and in 20 healthy individuals from the control group to get an insight into the lymphocyte metabolism. Statistically significant decrease of ADA activity was found in the groups of patients with chronic proliferative gn, membranoproliferative gn, membranous gn and lupus nephritis in comparison with the healthy individuals from the control group. As far as decrease of aldolase activity is concerned it has reached statistical significance in patients with mesangial gn, membranoproliferative gn, membranous gn and lupus nephritis. The lymphocyte metabolism did not show any abnormalities in the enzymatic indicators only in patients with acute proliferative gn and submicroscopic gn. The activity comparison between both enzymes in the lymphocytes, contrasted on the basis of high and low clinical dynamics of gn, revealed a tendency to lower ADA and aldolase activities in patients with high clinical dynamics. However, this difference was at the limit of statistical significance (p less than or equal to 0.10).  相似文献   
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