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A human monoclonal antibody (MCA), CLN-IgG, showed cytotoxic effect in vitro against the cervical carcinoma cell line, ME-180, by antibody dependent cell-mediated cytotoxicity (ADCC). To determine which fractions of cells in peripheral blood lymphocyte (PBL) mediate ADCC, PBL were separated with nylon wool column and sheep red blood cells (SRBC). Both adherent cells (monocyte) and non-T, non-B cells showed cytotoxicity by ADCC. Human non-T, non-B cells showed higher cytotoxic activity against ME-180 cells than monocytes. Furthermore murine effector cells were less effective in ADCC than human effector cells with human MCA.  相似文献   
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A 65-year-old woman presented with an episode of hematemesis and a recurrent cervical goiter due to Graves' disease. The angiogram revealed bleeding esophageal varices which had developed through a drainage vein of the vascular goiter. Total thyroidectomy resulted in eradication of the esophageal varices.  相似文献   
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Seminal findings and blood hormone levels were studied for evaluating the male reproductive function in patients with spinal cord injury. The patients were divided into 3 groups, namely, 18 patients with complete injury, 5 patients with incomplete injury and 3 patients with dyspermatism. The number of sperms, the rate of movement and rate of deformation were measured for semen obtained by forced ejaculation. The number of sperms was kept at a relatively high level in the three groups, while the rate of movement fell off in all of the three groups. The rate of deformation was highest in the patients with complete injury and lowest in the patients with dyspermatism. As for blood hormone levels, LH, FSH and Testosterone (hereinafter referred to as TES) were determined by the RIA. The cases were classified into those in the acute stage and those in the chronic stage 3 months after sustaining injury for a comparative study. The subjects consisted of 27 cases in the acute stage and 47 cases in the chronic stage. For 8 patients in the acute stage, the blood hormone levels were determined even in the chronic stage and follow-up observations were made on the changes in the levels. The FSH level was low in both stages, while LH and TES tended to increase in the chronic stage. Particularly, the TES level was elevated in all the cases in the follow-up observations made in 8 patients. From the results mentioned above, transient disturbance of the interstitial function is suggested as the mechanism of male gonadal disturbance due to spinal cord injury.  相似文献   
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The authors report an 18-year-old female who developed severe hemolytic reaction and delayed neutrophil recovery after bone marrow transplantation (BMT) for aplastic anemia from her HLA-identical sibling. She had received much transfusion (61 units of red blood cells including 4 units of fresh whole blood from her parents and 350 units of platelets) for 12 years before BMT. To prevent graft rejection, she received an intensified preparative regimen consisted of cyclophosphamide 200 mg/kg followed by 5 Gy total body irradiation and 5 Gy total lymphoid irradiation. Prophylaxis for GVHD was short term methotrexate and cyclosporin-A. Despite of the removal of the red cells from the marrow, marked hemolytic reaction caused by antibodies directed to rh" (E) and hr' (c) red cell antigens was observed when rh" (E) and hr' (c) positive donor erythroid began to recover. The recovery of neutrophils, especially the fraction of segmented cells was also delayed. Flow cytometry showed that the serially collected patient's sera reacted to neutrophils derived from both patient's blood on the 64th post-transplant day and the donor's blood. The reactivity was strongest in pre-BMT sera. We conclude that residual antibodies sensitized before BMT are a major cause of these hematological problems.  相似文献   
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Human parvovirus B19 (B19) infects cells of erythroid lineage. Production of neutralizing antibodies (Abs) is indispensable for recovery from B19-related disease state. In this study, we used a convenient method to measure neutralizing activities in human sera by using a real-time quantitative PCR based assay. Erythroid cell line KU812Ep6 was incubated with test sera before infection with B19 virus. The copy number of B19-DNA in cultures was decreased in the presence of the sera from patients who recovered from acute B19 infection, whereas no decrease in B19-DNA was in cultures incubated with sera from healthy volunteers who had no B19 infection. The decrease in B19-DNA copy number was calculated and the inhibition percentage was expressed as neutralizing activity to B19. A clinical study showed that the levels of neutralizing ability were high in patients who recovered soon after acute B19 infection, but were low in some patients with a prolonged clinical course for recovery from B19 infection. This method is simple and convenient compared with methods described previously, showing its usefulness to evaluate the neutralizing activity to B19.  相似文献   
9.
The reciprocal translocation t(1;3)(p36;q21) is associated with myelodysplastic syndromes (MDSs) and acute myeloid leukemia (AML) characterized by trilineage dysplasia, in particular dysmegakaryocytopoiesis, and a poor prognosis. As yet no molecular genetic analyses of the t(1;3) have been reported. In four patients with t(1;3), all of whom had AML-M4, which evolved from MDS, the breakpoints at 3q21 clustered within a 60-kb region centromeric to the breakpoint of the inv(3)(q21q26), whereas the breakpoints at 1p36 clustered within a 90-kb region at 1p36.3. The presence of novel clusters in both the 3q21 and 1p36 breakpoints (BCRs) suggests a common, underlying molecular mechanism for the development of t(1;3)-positive MDS/AML. The Ribophorin I (RPN1) gene close to the BCR at 3q21 was highly expressed without gross structural changes, whereas the GR6 gene located within the BCR at 3q21 was not expressed. No other highly expressed genes were isolated in a 150-kb region at 3q21. Thus, it is likely that a gene at 1p36.3 is activated by the translocation of the 3q21 region or a gene important for transformation lies on 3q21, outside the 150-kb region. Further characterization of the BCRs at 1p36.3 and 3q21 should provide important insights into the molecular genetic mechanisms involved in the genesis of t(1;3)-positive MDS/AML. Genes Chromosomes Cancer 27:229-238, 2000.  相似文献   
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To detect suppressor T cells to hematopoietic stem cells, growth of granulocyte-macrophage colony-forming cells (CFU-GM) and burst-forming unit (BFU-E) was compared before and after treatment of bone marrow cells with anti-T monoclonal antibodies and complement in 29 patients with aplastic anemia. The anti-T monoclonal antibodies used were 35.1 (CD2), Tp120 (CD6) and ATL27 (not clustered). Treatment of normal bone marrow with anti-T monoclonal antibodies and complement resulted in complete (greater than 99%) lysis of T cells with negligible effects on colony growth. Preincubation of marrow samples with monoclonal antibodies and complement did not enhance CFU-GM or BFU-E colony growth in patients with aplastic anemia. Using this assay, there was no evidence of T cell-mediated inhibition of colony proliferation in any of 29 patients.  相似文献   
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