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151.
It is shown that cultured Ehrlich ascitic carcinoma cells are a convenient test system for the investigation of the effects of various factors on DNA synthesis in the cells of this tumor. The application of this system markedly facilitates fractionation of a chalone-containing preparation, the purpose of this fractionation being the isolation of components affecting specific phases of the mitotic cycle. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 117, N o 1, pp. 80–82, January, 1994  相似文献   
152.
The dynamics of the synthesis of active oxygen forms by neutrophilic granulocytes was studied and compared in patients with systemic lupus erythematosus (SLE) given conventional therapy (n = 14) and combined therapy with the use of tactivin (n = 17). Evaluation of spontaneous fluorescence of neutrophils (FN) and of that induced by suspension of the killed Staphylococcus culture revealed an increase of the latter one after tactivin treatment, which was accompanied by the regression of articular and cutaneous syndromes and trophic disorders. It has been discovered that the dynamics of FN in the treatment with the use of tactivin was dependent on the initial characteristics of the synthesis of active oxygen forms.  相似文献   
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One hundred and sixty-three patients with major depression were randomly assigned to treatment with mirtazapine or doxepin for 6 weeks in a double-blind clinical trial. Initially, patients received mirtazapine 20 mg/day or doxepin 75 mg/day, dosages were then titrated up to a maximum of 60 mg/day and 300 mg/day, respectively. Both drugs produced considerable improvement in depressive symptoms with no statistically significant differences between the two patient groups. In the mirtazapine group only two patients prematurely terminated the study due to adverse drug experiences, as compared to six in the doxepin-treated group. Moreover, doxepin-treated patients complained more frequently of dry mouth and movement disorders. In conclusion, mirtazapine is an effective treatment for major depression and appears to offer advantages in tolerability over doxepin.  相似文献   
155.
The study was undertaken to develop basically new treatments of patients with sarcoidosis, namely: plasmapheresis and extracorporeal lymphocytic modification (ELM) with steroids, infrared laser or cytostatics. The authors analyzed the outcomes of treatment: 50 patients received plasmapheresis, in 52, 20, and 48 had ELM using prednisolone, infrared laser, and cyclosporin, respectively. Plasmapheresis used in the treatment regimen substantially reduced the dosage of corticosteroids. The outcomes of infrared laser therapy were comparable to those of plasmapheresis one. Positive clinical and X-ray changes of a tuberculous process were achieved with prednisolone or cyclosporin ELM in 95% of cases. As this took place, there were certain differences in the time course of X-ray changes. If prednisolone ELM promoted first of all reversal of interstitial changes, cyclosporin ELM affected a granulomatous process to a greater extent and alveolitis to a lesser one. Therapy-induced exacerbations were seen in none case. There were complications in 4% of cases.  相似文献   
156.
Proliferation of smooth muscle cells and deposition of extracellular matrix proteins are important events in the formation of atherosclerotic plaques. We have investigated the direct and matrix-mediated effects of ascorbate on the proliferation rate of vascular smooth muscle cells (VSMC) isolated from the guinea-pig aorta. In the presence of ascorbate, cells showed a bi-phasic growth pattern. At 125μmascorbate, [3H]-thymidine incorporation was stimulated 25%. However, higher concentrations of ascorbate gradually decreased cell-incorporated radioactivity up to 50% at 2 mmascorbate. These effects of ascorbate on DNA synthesis in VSMC were paralleled by the changes in cell number and were not due to ascorbate cytotoxicity. Alpha-tocopherol (0.1 mm), individually and in combinations with 1 mmascorbate, also inhibited DNA synthesis in VSMC. Ascorbate also influenced proliferation of smooth muscle cells through matrix-mediated effect. New VSMC culture plated on extracellular matrices deposited by smooth muscle cells in the presence of 0.1–1 mmascorbate had up to 50% lower proliferation rate than on matrices from ascorbate-deficient cells, as assessed by [3H]-thymidine incorporation. This effect was independent from alpha-tocopherol and specific inhibitors of collagen synthesis:l-azetidine-2-carboxylic acid and pyridine-2,4-dicarboxylic acid. An ascorbate-dependent matrix effect was specific for smooth muscle cells grown on VSMC and human skin fibroblast-originated matrices, but not for human vascular endothelial cells. The possible involvement of ascorbate in the regulation of smooth muscle cells proliferation by its antioxidant/pro-oxidant effects and regulation of extracellular matrix composition are discussed.  相似文献   
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159.
The characterization of cellular interactions with a biomaterial surface is important to the development of novel biomaterials. Traditional methods used to characterize processes such as cellular adhesion and differentiation on biomaterials can be time consuming, and destructive, and are not amenable to quantitative assessment in situ. As the development of novel biomaterials shifts towards small-scale, combinatorial, and high throughput approaches, new techniques will be required to rapidly screen and characterize cell/biomaterial interactions. Towards this goal, we assessed the feasibility of using 4-dimensional elastic light-scattering fingerprinting (4D-ELF) to describe the differentiation of human aortic smooth muscle cells (HASMCs), as well as the adhesion, and apoptotic processes of human aortic endothelial cells (HAECs), in a quantitative and non-perturbing manner. HASMC and HAEC were cultured under conditions to induce cell differentiation, attachment, and apoptosis which were evaluated via immunohistochemistry, microscopy, biochemistry, and 4D-ELF. The results show that 4D-ELF detected changes in the size distributions of subcellular organelles and structures that were associated with these specific cellular processes. 4D-ELF is a novel way to assess cell phenotype, strength of adhesion, and the onset of apoptosis on a biomaterial surface and could potentially be used as a rapid and quantitative screening tool to provide a more in-depth understanding of cell/biomaterial interactions.  相似文献   
160.
Ureaplasma parvum colonizes human mucosal surfaces, primarily in the respiratory and urogenital tracts, causing a wide spectrum of diseases, from non-gonococcal urethritis to pneumonitis in immunocompromised hosts. Although the basis for these diverse clinical outcomes is not yet understood, more severe disease may be associated with strains harboring a certain set of strain-specific genes. To investigate this, whole genome DNA macroarrays were constructed and used to assess genomic diversity in 10 U. parvum clinical strains. We found that 7.6% of U. parvum genes were dispersed into one or more strains, thus defining a minimal functional core of 538 U. parvum genes. Most of the strain-specific genes (79%) were of unknown function and were unique to U. parvum. Four hypervariable plasticity regions were identified in the genome containing 93% of the variability in the gene pool (UU32-UU33, UU145-UU170, UU440-UU447 and UU527-UU529). We hypothesized that one of them (UU145-UU170) was a pathogenicity island in U. parvum and we characterized it. Thus, we propose that the clinical outcome of U. parvum infection is probably associated with this newly identified pathogenicity island.  相似文献   
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