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Benfluron at concentrations of 0.26 and 0.52 mumol l-1 inhibited the formation of V79 colonies in a concentration-dependent way. Diminution of the size of colonies of the treated cells was accompanied by a decrease in protein content per cell. At the same time an increase in metabolic activity was observed. Benfluron blocked the V79 cells in S and G2 phases of the cell cycle and at higher concentrations induced cell lysis documented by alterations in cell membrane permeability and morphology. The in vitro membrane effect of benfluron involved a biphasic modulation of the cardiac sarcolemmal (Na+ + K+)-ATPase activity.  相似文献   
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The monoclonal antibody Bra23/9 (IgG2a) elicited by a non-T, non-B ALL cell line (REH), reacted in microscopic immunofluorescence, enzyme-linked immunoassay (ELISA), complement-dependent cytotoxicity tests and immunocytofluorometric measurements with hemopoietic cell lines and peripheral blood lymphocytes, monocytes and granulocytes from healthy donors in a pattern characteristic for MHC class I antigens. Immunoprecipitation of lactoperoxidase radioiodinated cell surface proteins and surface sialoglycoproteins radiolabeled by sodium metaperiodate/tritiated sodium borohydride technique confirmed the structure gp44,p12 (consisting of a 44 kDa glycopeptide linked with a nonglycosylated 12 kDa peptide) typical for MHC class I antigen(s) as a structure recognized by the Bra23/9 monoclonal antibody. The increase of MHC class I antigen density (immunofluorescence intensity) induced by a phorbol ester (TPA) in monoblast U 937 lymphoma cell line was observed by immunocytofluorometry as a predominant tendency in several TPA-induction experiments, where a certain variability among individual experiments in TPA-induced MHC class I antigen alterations was observed.  相似文献   
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Vernal catharr of the conjunctivae is frequently the initial symptom of dermorespiratory syndrome. In all nine children where ophthalmological and other manifestations of varying extent of general atopy were combined, the authors revealed a marked increase of immunoglobulin IgE 220-2230 I.U./ml (normal values up to 150 I.U./ml) and polyvalent allergy. In the treatment of vernal catharr the authors used a combination of antihistaminics and preventive immunopharmaceutical preparations administered locally (Spersallerg and Opticrom) or as general medication (Hismanal and Zaditen), supplemented by aimed hyposensitization. In acute stages of the inflammation of the eye the authors administered Triamcinolon into the upper transient conjunctival fold. In the treatment of secondary infection Garasone was most effective. A finding interesting from the immunological aspect was vernal catharr without general symptoms of atopy in a patient with hypogammaglobulinaemia IgA.  相似文献   
16.
Toxoplasma gondii (T. gondii) is the cause of toxoplasmosis. Primary infection in an immunocompetent person is usually asymptomatic. Serological surveys demonstrate that world-wide exposure to T. gondii is high (30% in US and 50–80% in Europe). Vertical transmission from a recently infected pregnant woman to her fetus may lead to congenital toxoplasmosis. The risk of such transmission increases as primary maternal infection occurs later in pregnancy. However, consequences for the fetus are more severe with transmission closer to conception. The timing of maternal primary infection is, therefore, critically linked to the clinical manifestations of the infection. Fetal infection may result in natural abortion. Often, no apparent symptoms are observed at birth and complications develop only later in life. The laboratory methods of assessing fetal risk of T. gondii infection are serology and direct tests.Screening programs for women at childbearing age or of the newborn, as well as education of the public regarding infection prevention, proved to be cost-effective and reduce the rate of infection.The impact of antiparasytic therapy on vertical transmission from mother to fetus is still controversial. However, specific therapy is recommended to be initiated as soon as infection is diagnosed.  相似文献   
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Fifty-four patients with complicated UTI were administered ciprofloxacin in doses of 500 mg (30 subjects) and 250 mg (24 subjects) at 12-hour intervals. While a positive effect was noted in 96–100% upon termination of therapy, the effect was still present 3 weeks later in 90% of the high-dose, but only in 71% of the low-dose group. In 23 patients with uncomplicated UTI, a positive effect of the three-day therapy with 100 mg of ciprofloxacin at 12-hour intervals was observed in 91% of subjects. Intolerance to the agent was found in one case only. Development of resistance to ciprofloxacin was not observed.  相似文献   
18.
Soluble antigen HLA-B27 was assayed in blood serum of 30 patients afflicted with ankylosing spondyloarthritis (AS) and 25 healthy subjects having HLA-B27 (B27+) antigen in the phenotype. As compared to B27+ healthy subjects, B27+ patients with AS demonstrated a significantly higher level of soluble HLA-B27 antigen. A substance whose functional activity was found to be identical to that of soluble HLA-B27 antigen in blood serum of B27- patients with AS was discovered for the first time. It was absent from B27- healthy subjects. In addition to the identification of the fixed forms of soluble HLA-B27 antigen, the assay of this antigen in blood serum enhances the potentialities of laboratory diagnosis of AS, which plays an important role at the early disease stages.  相似文献   
19.
The optical coherence tomography method was explored for two-dimensional flow mapping of a highly scattering fluid in flow with complex geometry. Converging flow (capillary entry) with 4:1 constriction was used for demonstration of non-invasive and remote methods of mapping varying velocity profiles. Downstream of the geometry was scanned with approximately 10 x 10 x 10 microm3 spatial resolution and structural imaging of the lumen and images of one particular velocity were acquired. Stable concave, blunted and parabolic profiles are obtained at different distances of the inlet length. Application of the technique for the blood circulation is also discussed.  相似文献   
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