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1.
The effect of 8.15-18 GHz (1 Hz within) microwave radiation at a power density of 1 microW/cm2 on the tumor necrosis factor (TNF) production and immune response was tested. A single 5 h whole-body exposure induced a significant increase in TNF production in peritoneal macrophages and splenic T cells. The mitogenic response in T lymphocytes increased after microwave exposure. The activation of cellular immunity was observed within 3 days after exposure. The diet containing lipid-soluble nutrients (beta-carotene, alpha-tocopherol and ubiquinone Q9) increased the activity of macrophages and T cells from irradiated mice. These results demonstrate that irradiation with low-power density microwaves stimulates the immune potential of macrophages and T cells, and the antioxidant treatment enhances the effect of microwaves, in particular at later terms, when the effect of irradiation is reduced.  相似文献   
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Physics of the Solid State - The change in the bulk modulus of coarse-crystalline and nanocrystalline silver sulfides is determined in the temperature range 300–960 K using the experimental...  相似文献   
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Products of conversion of the ferrous oxide catalyst collected from the burning region of an AP-PMMA mixture show the significant aggregation of the catalyst, with large (40–50 m) spherical particles having a metallic glitter. Significant variations in the phase composition are observed, Fe3O4·-Fe2O3 solid solution and tetragonal and monoclinic Fe2O3 being formed.
- a-Fe2O3 . . ( 40–50 ) . : Fe3O4·-Fe2O3, Fe2O3.
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Background  

Growth hormone (GH) plays an incompletely understood role in the development of the central nervous system (CNS). In this study, we use transgenic mice expressing a growth hormone antagonist (GHA) to explore the role of GH in regulating postnatal brain, spinal cord and body growth into adulthood. The GHA transgene encodes a protein that inhibits the binding of GH to its receptor, specifically antagonizing the trophic effects of endogenous GH.  相似文献   
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Equations relating the N-acylation rate constants of glycine, L--alanine, DL-threonine, and L-proline with 4-nitrophenyl 4-nitrobenzoate in water-acetonitrile, water-2-propanol, and water-2-methyl-2-propanol solvents to the composition of the medium were obtained, and reaction rate constants in water were calculated.  相似文献   
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Procedures for the determination of 04sobutyl- S-2-(N,N-diethylamino)ethyl methylphosphonothioate (VX-like compound) and sarin traces in slag at levels of 5 × 10-5 and 1 × 10-2 mg/kg, respectively, were developed. The procedures are based on the extraction of organophosphorus chemical warfare agents from slag, the preconcentration of the extract, and the conversion of the analytes into dialkyl methylphos-phonates with the use of optically active alcohols. In this case, a solution of AgNO3 in 4-methyl-2-pentanol or a sodium alcoholate solution was used for the derivatization of VX or sarin, respectively. The resulting dias-tereomers were determined by gas chromatography with the use of a flame-photometric detector. The analysis time was no longer than 1.2 or 1 h for the VX-like compound or sarin, respectively.  相似文献   
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