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881.
The objective of this study was to develop a method for measuring the mobility of persistent organic pollutants in the solid phase of soils within the context of environmental pollution risk assessment. A new diffusive probe, purposely designed by adapting the diffusive gradient technique method, measures labile organic species by immobilizing them after diffusion through a thin deionized water layer. The measure of the mass accumulated is used to calculate the flow of pollutant from solid phase to pore water. Naphthalene was chosen as a model persistent organic pollutant. The probe was calibrated at different temperatures and was then tested in several microcosms at different porosity and reactivities with naphthalene (one clay soil, two sandy soils and one natural soil). The probe response showed good agreement with the expected different abilities of the solid phases in restoring the solution phase. The concentration of naphthalene in the pore water was well buffered by rapid equilibria with the solid phase in the investigated natural soil. In contrast, pore water concentration in the sandy soils decreased rapidly and the flow was slackened, especially for the sandy soil with finer particles. In clay, only a fraction of the total naphthalene content was present in the labile fraction, while the remaining was tightly bound and was not released to the pore water. Therefore, this first stage of testing points out that the diffusive gradient technique, if optimized, can properly quantify the mobility of organic pollutants in soil.  相似文献   
882.
Results of complex treatment of severe combined traumas were compared in 56 patients with using cryosupernatant plasma fraction (CSPF) and fresh frozen plasma--in 112 patients. Better positive dynamics of some laboratory indices was noted as well as lower risk of the development of thromboses, less lethality and better outcomes of the disease when using CSPF. It can be used instead of fresh frozen plasma in complex treatment of patients with severe combined traumas and coexisting DBC-syndrome.  相似文献   
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The necessity to minimize adverse effects of tuberculosis chemotherapy requires a comprehensive evaluation of the effects of antituberculosis drugs on the reproductive system and testicular cell macromolecules. The epidemiological situation of tuberculosis in Central and Eastern Europe is getting worse. Data on adverse effects of antituberculosis drugs are scare concerning particularly their effects on the reproductive system. The aim of the present study was to investigate the potential effect of ethambutol, rifampicin, isoniazid and pyrazinamide co-administration on lipid peroxidation, glutathione content and protein SH-groups, DNA fragmentation levels, the reproductive capacity of Wistar male rats and the antenatal development of their posterity. The rats (150-170 g) were divided into two groups: group I - received antituberculosis drugs suspended in 1% starch gel per os: ethambutol - 155 mg/kg b.w./day, rifampicin - 74.4 mg/kg b.w./day, isoniazid - 62 mg/kg b.w./day, pyrazinamide - 217 mg/kg b.w./day, group II (control) - received only starch gel in corresponding volumes. The contents of TBA-active compounds, glutathione and protein SH-groups in testis and sperm were determined spectrophotometrically, the DNA-fragmentation was determined using an UV transilluminator (BIORAD, USA), reproductive system indices were measured by standard methods. The co-administration of therapeutic doses of ethambutol, isoniazid, rifampicin and pyrazinamide to male rats during the period of spermatogenesis caused an increase in the rate of thiobarbituric acid reactive substances formation in testis and sperm, decrease of testis glutathione and protein SH-group contents, significant changes in DNA fragmentation, fatal decrease of male fertilizing capacity and fertility, and increase of pre- and post-implantation embryo lethality. The changes in reproductive indices could be the result of direct or indirect effects of one or more drugs investigated.  相似文献   
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Neurospecific proteins S-100 and GFAP were measured in the serum of 145 patients with neural tumors and 69 healthy individuals. In patients with glyoblastomas, the concentrations of S-100 and GFAP were significantly higher than in patients with anaplastic astrocytomas, benign meningiomas, and brain metastases and in healthy individuals. Serum S-100 concentrations in patients with anaplastic astrocytomas, benign meningiomas, and brain metastases were similar; significant difference from the control was found only for patients with cerebral metastases. A specific feature of GFAP was high incidence of its detection in patients with glioblastomas (83%) compared to other groups of patients with neural tumors and healthy volunteers who demonstrated practically zero level of this protein. These findings attest to the possibility of using S-100 as an additional biochemical criterion of brain involvement in tumor patients and GFAP as a glioblastoma marker.  相似文献   
889.
Glycation of a recombinant monoclonal IgG2 molecule, in sucrose containing liquid formulations, was studied using reversed-phase LC/MS analysis of the intact IgG, the F(ab')2 fragments and after complete tryptic digestion. The extent of glycation in sucrose containing formulations was monitored at different temperatures over a period of 21 months using the Hexose index (Hex(I)). Hex(I) represents the average number of hexose molecules per molecule of IgG and was calculated by using the intensity values of peaks corresponding to hexose isoforms in the deconvoluted mass spectra. The rate of glycation in mildly acidic sucrose containing formulations was proportional to the incubation temperature. No glycation was observed in sucrose containing formulations incubated at 4 degrees C even after 18 months. However, when the same formulations were incubated at 37 degrees C glycation was observed after just 1 month. The glycation sites were mapped to 10 lysine residues distributed throughout the molecule. The amino terminal end of the light chain was also shown to contain glycation. The surface accessibility of the lysine side chain could influence its susceptibility to glycation.  相似文献   
890.
The blood level of nitric oxide (NO) was studied during an infectious process in 107 patients with leptospirosis. The content of NO was estimated from the level of the final stable nitrogen cycle metabolite--nitrite was estimated by the Griss reaction. Infectious toxic shock (57%), disseminated intravascular coagulation syndrome (31%), respiratory distress syndrome (36%), and acute renal and hepatic failure (76%) were observed in the examinees. A combination of 3-4 of the above abnormalities was noted in 49% of the patients. There were elevated blood nitrite levels at the onset of the disease in patients with leptospirosis with signs of infectious toxic shock (15.3+/-2.79 micromol/l). In patients with a poor or complicated rehabilitative period, the high levels of nitrite were retained or its concentration repeatedly increased at weeks 3-4 of the disease. It has been shown that the measurements of blood nitrite levels may be used as an additional diagnostic criterion for evaluating the course of leptospirosis.  相似文献   
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