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We investigated the effects of rufloxacin, a new, long acting fluoroquinolone, on the growth and differentiation of human peripheral blood mononuclear cells (MNC) stimulated with T- and B-cell mitogenic agents. Rufloxacin inhibited 3H-thymidine incorporation into MNC stimulated with phytohaemagglutinin (PHA) and pokeweed mitogen (PWM) in a dose-dependent manner. The concentrations of rufloxacin required to inhibit 1/2 maximal proliferation of T- and B-cells were 62 and 33.5 mg/L respectively. Rufloxacin, at clinically achievable serum levels (less than 10 mg/L), was found not to inhibit PHA-induced T-cell differentiation as assessed by IL-2 production, IL-2 receptor expression and the expression of cell differentiation markers (CD4 and CD8). However, higher concentrations of rufloxacin (10 and 50 mg/L) markedly inhibited B-cell differentiation in-vitro as determined by the measurement of immunoglobulin production by MNC stimulated with PWM. The clinical relevance of our in-vitro findings remains to be elucidated.  相似文献   
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Both electroencephalography (EEG) and magnetoencephalography (MEG) localize epileptiform activity but may yield different results. This discordance may arise from different detection capabilities or from different data collection and interpretation techniques. Comparisons of MEG and EEG have focused on detection of individual spikes. However, side-by-side comparisons of results as used in the clinical setting is lacking. In this report, we present our empirical comparison. We reviewed 58 simultaneous MEG-EEG recordings (35 paired-sensors, 23 whole-head) from a diverse epilepsy population, comparing previous clinical MEG interpretations with new blinded EEG interpretations, noting lobar concordance of readers' judgments of regional abnormalities. A second-pass unblinded analysis, using all available clinical data, assessed the relative contribution and plausibility of the results of each technique. Concordance was high (85%) overall. Discordance was sometimes caused by constraints imposed by MEG dipole fitting techniques. Even when results of the techniques did not match, MEG often disambiguated the clinical scenario, especially when combined with imaging information. Thoughtful analysis of combined MEG-EEG datasets, beyond algorithm-based interictal spike detection, can help guide clinical decision-making even when concordance between techniques is imperfect. In some cases, EEG and MEG are synergistic and provide complementary information.  相似文献   
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A series of nevirapine derivatives has been synthesized in an effort to enhance the spectrum of chemotherapeutic properties for the effective treatment of AIDS and AIDS-related opportunistic infections. The nevirapine derivative bearing isoniazid moiety (3a) was found to be the most potent compound with EC50 of<0.0636 microM, CC50 of>1000 microM and selectivity index of>15,723 which also exhibited 90% inhibition against Mycobacterium tuberculosis at 6.25 microg/ml. Compound 3c showed 100% inhibition against M. tuberculosis and also exhibited potent antibacterial activity against 24 pathogenic bacteria with MIC less than 1 microg/ml.  相似文献   
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We determined the location of excitation for different positions of a round and butterfly coil duringin vitro magnetic stimulation of cut peripheral nerves. We analyzed the conditions under which excitation occurs, either at the termination or at the peak of the field gradients (first spatial derivative of the electric field). These results were then compared to predictions about the location of excitation sites from a theoretical model of magnetic stimulation of finite neuronal structures. Excitation along a straight nerve occurred at terminations when 1) a coil was positioned close to the end of a nerve (at least one diameter length from the end), 2) a nerve ended in a finite terminating impedance much greater than the axial resistance of the nerve, 3) the induced electric field was of sufficient magnitude, pointing in a direction away from the axis of a nerve. Excitation occurred at the negative peak of the field gradients along a nerve when 1) a coil was positioned far away from the ends of a nerve, 2) there were no geometric or volume conductor inhomogeneities around a nerve, and 3) it was of sufficient magnitude. Threshold strengths for excitation at terminations were significantly lower than that for field gradient excitation and comparable to that due to geometric and volume conductor inhomogeneities.  相似文献   
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Sulfatide, ceramide galactosyl-3'-sulfate, is mainly present in nervous tissue, kidney, testis, red blood cells, platelets and granulocyte. Antibodies to sulfatide are present in many patients with demyelinating peripheral neuropathy, HIV infection and systemic lupus erythematosus and may account for some of the clinical manifestations. To evaluate the effect of such antibodies, we have constructed a phage-display antibody fragment library from the lymphocytes of patients with systemic lupus erythematosus. Sulfatide-reactive phage were selected by absorption and elution on sulfatide liposomes and soluble single chain variable fragment (ScFv) were isolated from individual colonies and tested in an ELISA assay for binding to bovine brain sulfatide. Five ScFv clones that bound sulfatide were isolated. Two of the clones, PH5 and PA38, bound sulfatide but not phosphatidylserine, phosphatidylcholine, phosphatidylethanolamine, sphingomyelin or ceramide. These two clones also bound sulfatide from human red blood cells. The DNA encoding the fragments was sequenced, revealing predicted polypeptides of 19 kDa for PH5 containing only variable heavy (VH) sequences, and 31 kDa for PA38, with both VH and variable light (VL) sequences. Although they had similar antigen specificities, the VH domains of the two clones were derived from different heavy-chain families. The clustered mutational patterns in the complementarity-determining region (CDR) of the heavy chains in both clones suggest that the V-domains are the products of antigen-driven B cell clonal maturation leading to the development of sulfatide-binding specificity. These results show the presence of sulfatide-specific antibodies in lupus patients, and allow us to test the possibility that the interaction of the antibodies with sulfatide may contribute to some of the symptoms. In addition, the antibodies provide useful reagents to test the role of sulfatide in pathophysiological processes.  相似文献   
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Hepatic capillariasis   总被引:6,自引:0,他引:6  
The clinico-pathologic features of Capillaria hepatica infection in a 27-year-old Nigerian woman are discussed. This animal parasite has been encountered only rarely in humans. Less than 30 cases of human infection, mostly in children, having been recorded as far as the present authors are aware. This is the first case of hepatic capillariasis reported in West Africa. The pathologic features of this patient is marked by severe hepatic fibrosis, and this is correlated with disordered liver function. The possibility of histopathologic confusion with schistosomiasis mansoni is discussed.  相似文献   
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