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71.
The hypotensive and vasorelaxing peptides adrenomedullin (AM) and its gene-related peptide, proadrenomedullin N-terminal 20 peptide (PAMP), were found to be distributed on the surface of the colonic mucosa. AM and PAMP showed dose-dependent antimicrobial activity against E. coli. The results suggest that the novel vasoactive peptides AM and PAMP play an important role in mucosal defence.  相似文献   
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Cells from 203 children with leukemia/lymphoma were analyzed by the FAB (French-American-British) system using a broad panel of markers such as immunological marker studies, Southern blot and Northern blot analyses to establish a lineage specific classification of childhood leukemia. Phenotypically, they were divided into B-lineage (62.6%), T-lineage (9.8%), non-lymphoid (14.3%) and uncertain lineage (13.3%). Two B-lineage ALL cells and two T-lineage ALL cells studied did not show immunoglobulin (Ig) or T-cell receptor (TCR) gene rearrangements, respectively. Therefore, those four cases were excluded from the final classification. The uncertain lineage leukemia, which includes undifferentiated leukemia and mixed lineage leukemia, were further subclassified at the DNA and RNA levels. The definitions of B-lineage and T-lineage cells, incidence of dual genotypes or spillover, heterogeneity of undifferentiated leukemia, and a new classification for mixed lineage leukemia were discussed.  相似文献   
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In order to clarify the role of CD5 antigen on B cell in autoimmunity, we examined B cells from patients with rheumatoid arthritis (RA). The percentages of CD5 positive B cells were increased in peripheral blood from RA compared with normal. Normal and RA B cells were stimulated with two kinds of monoclonal antibodies to CD5 (Leu-1, SL-1) which recognize different epitopes. RA B cells proliferated and secreted IgM by CD5 antibody stimulation in combination with IL-1. Our observations imply that CD5 positive B cells in RA are in their differentiation stage and that CD5 antigen might be one of the triggers to activate CD5 positive B cells in vivo to produce autoantibody.  相似文献   
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Cigarette smoke condensate (CSC) was separated into severalfractions and each was tested for an inhibitory effect on theearly antigen (EA) of Epstein-Barr virus (EBV) which can beinduced by 12-0-tetradecanoylphorbol-13-acetate (TPA) in Rajicells. Two diastereoisomers of 2,7,11-cembratriene-4,6-diol(- and ß-CBT) were isolated from the neutral fractionsof CSC and these showed potent inhibitory effects on the inductionof EBV-EA by TPA. The doses of - and ß-CBT requiredfor 50% inhibition of EBV-EA induction by TPA were 7.7 and 6.7µg/ml, respectively, which are comparable with those ofretinoic acid, a potent inhibitor of induction of epideral ornithinedecarboxylase (ODC) activity and tumor promotion by TPA in mice.Application of - and ß-CBT to mouse skin prior totreatment with TPA inhibited TPA-induced ODC activity. The degreeof inhibition was dependent on the dose and application of 16.5µmol/mouse of - and ß-CBT resulted in a 50 and40% reduction, respectively, of the maximum of the ODC activityinduced as a result of treatment with TPA. In initiation-promotionexperiments, -CBT markedly inhibited the promoting effect ofTPA on skin tumor formation in mice which were initiated with7,12-dimethylbenz[a]anthracene, but ß-CBT was foundto be less effective. Application of 3.3 µmol of -CBT40 min prior to treatment with TPA (1 µg) resulted ina 53% reduction in the number of papillomas per mouse. Our presentdata suggest that EBV-EA inhibition assay using Raji cells iseffective for the first screening of inhibitors of tumor promotion,and provide evidence that CSC contains antitumor-promoting agentsin addition to carcinogenic and tumor-promoting agents alreadyreported.  相似文献   
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A 65-year-old man was admitted for dysuria. He had been irradiated 60Co for malignant lymphoma of tonsils 2 years earlier. The findings of palpation of prostate, retrograde urethrogram and urethroscopy strongly suggested benign prostatic hypertrophy. Retropubic prostatectomy was performed and 18 g of "adenoma" was resected. By histological observation, the "adenoma" proved to be malignant lymphoma. This tumor belonged to follicular lymphoma, medium-sized cell type of LSG non-Hodgkin's lymphoma classification. After the operation, he left our hospital for a personal reason and received systemic chemotherapy at another hospital.  相似文献   
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