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51.
The most frequent nonrandom chromosome rearrangements in B-cell non-Hodgkin lymphoma (NHL) is the t(14;18)(q32;q21) found in follicular lymphomas. The t(14;18) in Hodgkin disease (HD) was rarely observed using cytogenetic techniques. Although Southern blot analysis failed to demonstrate the t(14;18), there have been conflicting reports concerning the occurrence of the translocation using polymerase chain reaction (PCR) methods in HD. In some HD tissues, the translocation might be derived from background lymphocytes rather than Hodgkin and Reed-Sternberg (HRS) cells, because B-cells with t(14;18) are regularly generated in normal individuals. However, the cells bearing the translocation have remained unidentified. We describe a patient with HD who showed t(14;18) in hyperdiploid cells using fluorescence in situ hybridization (FISH) and HRS cells which were strongly positive for BCL2 by immunohistochemistry. These findings suggest that HRS cells may have a t(14;18).  相似文献   
52.
Thymosin alpha 1 was shown to prevent the 5-fluorouracil(5-FU)-induced bone marrow toxicity in BDF1 mice, as determined by the cellularity, haemopoietic stem cells (CFU-s) and granulocyte-macrophage colony forming unit (GM-CFU). Furthermore, thymosin alpha 1 increased the levels of colony stimulating factor (CSF) in sera or in culture media of spleen cells derived from 5-FU-treated mice. The treatment of spleen cells with anti-Thy 1,2 antibody plus complement abolished completely the CSF production. The in vivo treatment of donor mice with anti-Thy 1,2 antibody following 5-FU abolished completely the capability of their bone marrow cells to save lethally irradiated recipients. Thymosin alpha 1 treatment prevented the damage by such combined treatment. The present study indicates that thymosin alpha 1 exerts its protective effect against the 5-FU-induced bone marrow toxicity, at least partially, through its effect on the maturation of immature T cells to functional T cells which produce various kinds of lymphokines including CSF.  相似文献   
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We performed a nationwide epidemiologic study of hypersensitivity pneumonitis (HP) in Japan by questionnaire and found that 835 cases of HP were recognized during the 1980s; 74.4% were summer-type HP, 8.1% farmer's lung, 4.3% ventilation pneumonitis, 4.1% bird fancier's lung, 2.3% other types, such as chemical worker's lung, and 6.8% of unknown causative agent. It was found that the CD4/CD8 ratios of bronchoalveolar lavage (BAL) lymphocytes were significantly different with the type of disease. The ratio was 0.6 +/- 0.1 (mean +/- SEM) in summer-type HP (N = 271), 4.4 +/- 0.7 in farmer's lung (N = 22), 1.6 +/- 0.3 in ventilation pneumonitis (N = 19), and 2.0 +/- 0.5 in bird fancier's lung (N = 19). In farmer's lung, the CD4/CD8 ratio in smokers was 6.2 +/- 1.9 (N = 6) in contrast with 3.4 +/- 0.7 for nonsmokers (N = 16) (p less than 0.05). It has been generally considered that the phenotypes of BAL lymphocytes in patients with HP are predominately CD8 cells. Our present results, however, indicate that the phenotypes of BAL lymphocytes vary with the type of HP, probably depending on factors such as causative agent, smoking, or staging of the disease.  相似文献   
55.
The specific immunophenotypic characterization of the hematologic malignant diseases has been obtained most commonly by the immunofluorescent technic. It requires a microscope with illuminator or the expensive flow cytometer that usually precludes morphologic assessment. It was compared with the indirect rosette assay and the immunoperoxidase study, which allowed both immunologic and morphologic assessment. These three technics appeared to be comparable quantitatively, and the latter two technics utilizing cytospin preparations were applied sequentially to the leukemic cells of adult T-cell leukemia with a complex phenotype (OKT4+/OKT8+) and successfully displayed the double markers on each leukemic cell.  相似文献   
56.
Acute ulcerative colitis associated with cytomegalic inclusion virus   总被引:2,自引:0,他引:2  
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57.
By a direct immunofluorescent technique, glomerular C3d deposition was examined in a total of 50 renal biopsy specimens from patients with lupus nephritis. C3d deposition was then compared with disease activity, glomerular IgG and C3c deposition, and the levels of circulating immune complexes (CIC) measured by a solid-phase anti-C3d assay. There was a good correlation between disease activity and the positivity of glomerular C3d deposits (P less than 0.001), as well as C3c deposits (P less than 0.001). Even in clinically inactive patients, a relatively high percentage (59%) of C3d deposits were positive compared with C3c deposits (17%). Mesangial C3d deposition correlated with clinical disease activity more significantly (P less than 0.005) than capillary wall C3d deposition (P less than 0.025). C3d deposits were detected in all of the 30 cases with positive C3c deposits, and moreover, in 15 of the 20 (75%) cases with negative C3c deposits. Glomerular IgG deposits were almost always associated with C3d deposits, both in mesangial areas and along capillary walls, with statistical significance (P less than 0.005, P less than 0.001, respectively). The serum levels of C3d-fixing immune complexes (IC) were significantly correlated with the positivity and intensity of mesangial C3d deposits. This study demonstrates glomerular deposition of C3d in patients with lupus nephritis and reveals a significant correlation between mesangial C3d deposition and disease activity.  相似文献   
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59.
A reverse, or IgE-capture, enzyme-linked immunosorbent assay (ELISA) for measuring ovalbumin-specific IgE antibody in the serum of immunized mice has been developed. Microplate wells were first coated with a commercial anti-mouse IgE rat monoclonal antibody, and then incubated with two-fold serial dilutions of test sera with 10% normal mouse serum as diluent for the capturing of only IgE class molecules. Biotinylated ovalbumin and then beta-D-galactosidase-conjugated streptavidin were added and, finally, 4-methylumbelliferyl-beta-D-galactoside was used as the enzyme substrate. The fluorescence intensity of the reaction product (4-methylumbelliferone) was determined on a microplate fluorescence reader. The sensitivity of this assay was equal to that of passive cutaneous anaphylaxis (PCA). In contrast to indirect ELISAs this IgE-capture assay is free from competition by non-IgE antibodies. Furthermore, it requires much less antigen than the PCA assay.  相似文献   
60.
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