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41.
Two-month old Wistar rats of both sexes received, as sole drinking liquid, an aqueous solution of ammonium metavanadate (AMV) at a concentration of 0.01 or 0.05 mg V cm–3 (0.2 or 1.0 mM) for a period of 4 weeks. It was calculated that the animals took up doses of 1.5 and 5–6 mg V kg body weight–1 24 h–1, respectively. Food and AMV solution consumption in the experimental groups was similar to food and water consumption in the control group. A statistically significant decrease of consumption of AMV solution at a concentration of 0.05 mg V cm–3 was noted only in males. Hematological examination demonstrated a decrease in the erythrocyte count, hemoglobin level and hematocrit index. This decrease in the erythrocyte count was associated with an increased percentage of reticulocytes in the peripheral blood of the animals drinking the solution with a higher vanadium content. Biochemical analyses demonstrated a decrease of l-ascorbic acid levels in the plasma and erythrocytes of animals drinking the AMV solutions. A distinct tendency for the malonyldialdehyde level to increase in the blood was also observed. Among the enzymes examined in the erythrocytes (catalase, glucose-6-phosphate dehydrogenase, lactate dehydrogenase and -aminolevulinic acid dehydratase [ALA-D]) only ALA-D activity was depressed. 相似文献
42.
43.
Czesaw ugowski Tomasz Niedziela Wojciech Jachymek 《FEMS immunology and medical microbiology》1996,16(1):31-38
Abstract A hybridoma cell line producing a human anti-lipid A monoclonal antibody (mAb), FKF-1F3 (IgM (κ)) was obtained by cell fusion of Epstein-Barr virus-transformed cells and mouse myeloma. The mAb bound to not only Gram-negative bacterial lipid A, but also to polysaccharide portions of Pseudomonas aeruginosa lipopolysaccharides (LPS). The mAb seemed to recognize two distinct regions of P. aeruginosa LPS other than lipid A, namely the outer core regions of some serotype strains and the O -polysaccharide region of serotype A strains. The mAb cross-reacted with N -acetyl-β-glucosamine-conjugated bovine serum albumin, N -acetyl-β-galactosamine-conjugated bovine serum albumin, myosin and actin, but not with other autoantigens such as ss- and ds-DNA, cardiolipin and glycosaminoglycans. The mAb conferred protective activity against a mouse pseudomonal infection model. The evidence suggested that the mAb was a naturally occurring polyspecific antibody that participated in defense against pseudomonal infections. 相似文献
44.
Przybyłowski J Kowalski D Widłak H Kowalska K Maślany P 《Polski tygodnik lekarski (Warsaw, Poland : 1960)》1995,50(1-35):794-796
In 66 patients with peptic ulcer (11 with gastric ulcer, 55 with duodenal ulcer, 19 women, 47 men) the serum concentrations of prolactin, dehydrocholic acid and gastrin were determined. The studies were repeated after treatment with ranitidine: in 50 patients after three weeks and in 40 patients after another 30 days. During the first period ranitidine 2 x 150 mg was administered, while during the second period the dose was 1 x 150 mg. The results were compared with those obtained from 120 healthy subjects. Before starting the treatment prolactin levels were significantly higher than those in the control group. During the treatment a significant decrease of the levels was observed. Similar changes of prolactin concentrations were found in the group of 39 men with duodenal ulcer isolated from the studied patients, who were compared with a group of 50 healthy men. It was not found that the development of peptic ulcer and the treatment with ranitidine exerted and effect on the changes of gastrin and dehydrocholic acid concentrations. 相似文献
45.
46.
Paweł Kafarski Barbara Lejczak Roman Tyka Lucyna Koba Elżbieta Pliszczak Piotr Wieczorek 《Journal of Plant Growth Regulation》1995,14(4):199-203
A series of phosphonic, phosphinic, and phosphonous acid analogues of phenylglycine and phenylalanine was synthesized and tested as herbicides against Lepidium sativum and Cucumis sativus. Aminobenzylphosphonic acids exhibited notable herbicidal activity and thus represent a group of the most active herbicides found among aminophosphonic acids. 相似文献
47.
Witold Lasek Anna Wańkowicz Katarzyna Kuc Wojciech Feleszko Jakub Golab Adam Giermasz Wiesŀaw Wiktor-J/cedrzejczak Marek Jakóbisiak 《Cancer immunology, immunotherapy : CII》1995,40(5):315-321
The efficacy of systemic infusion of recombinant human macrophage-colony-stimulating factor (M-CSF) in combination with local treatment with human recombinant tumor necrosis factor (TNF) and mouse recombinant interferon (IFN) was studied in vivo on a subclone of B16 melanoma (MmB16) in mice. Short-term intravenous administration of M-CSF at a dose of 106 units daily had no antitumor effect in vivo. Similarly, local treatment of tumor with TNF (5 g daily) did not produce any therapeutic effect. However, simultaneous administration of the same dose of TNF with IFN (1000 units daily) resulted in a synergistic effects manifested by the retardation of tumor growth. Addition of systemic infusion of M-CSF to the local therapy with TNF and IFN induced further augmentation of antitumor efficacy and delayed progression of MmB16 melanoma. The strengthened antitumor effect of combination therapy including M-CSF, TNF and IFN was most probably due to the increased release of monocytes from the bone marrow, their recruitment into the site of tumor growth and subsequent local stimulation of their antitumor activity. 相似文献
48.
Two series of amino-modified silicate gels prepared by sol-gel processing were used to absorb Cu(II), Ni(II), Co(II), Mn(II) and Cr(III) from aqueous solutions. These easily prepared sorbents with various content of primary amino groups in series (A) or primary and secondary amino groups in series (AA) have reasonable stability. The gel composition, time and concentration dependence of the uptake of the metal ions by these materials were studied systematically. These materials would be further used as supports to disperse catalytically active phases by conventional wet chemical procedures. Apart from this they demonstrate potential for the preconcentration aid for transition metal analysis. 相似文献
49.
Gracjana Klein Robert Walczak Ewa Krasnowska Adam Blaszczak Barbara Lipiska 《Molecular microbiology》1995,16(4):801-811
We have investigated heat-shock response in a marine bacterium Vibrio harveyi. We have found that 39 C was the highest tempature at which V. harveyi was able to grow steadily. A shift from 30° C to 39° C caused increased synthesis of at least 10 proteins, as judged by SDS-PAGE, with molecular masses of 90, 70, 58, 41, 31, 27, 22, 15, 14.5 and 14kDa. The 70, 58, 41 and 14.5 kDa proteins were immunologically homologous to DnaK, GroEL, DnaJ and GroES heat-shock proteins of Escherichia coli, respectively. V. harveyi GroES protein had a lower molecular mass (14.5 kDa) than E. coli GroES, migrating in SDS-PAGE as 15 kDa protein. We showed that a protein of ~43 kDa, immunologically reactive with antiserum against E. coli sigma 32 subunit (σ32) of RNA polymerase, was induced by heat-shock and co-purified with V. harveyi RNA polymerase. These results suggest that the 43 kDa protein is a heat-shock sigma protein of V. harveyi. Preparation containing the V. harveyi sigma 32 homologue, supplemented with core RNA polymerase of E. coli, was able to transcribe heat-shock promoters of E. coli in vitro. 相似文献
50.
Barbara Płytycz 《Immunogenetics》1984,19(1):3-11
The major histocompatibility complex (MHC) zygosity of the field-collected frogs, Rana temporaria, was detected by progeny testing. Groups of sibling tadpoles were grafted with intrafamilial tail-tip allografts and the ratio of rapidly rejected allografts to slowly rejected ones was estimated. Twenty-five percent of parental frogs appeared to be MHC homozygotes. Thus, MHC homozygosity in natural frog populations seems to be considerably higher than in wild mouse populations. 相似文献