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We report the results of reduced-intensity unrelated cord blood transplantation (RI-UCBT) in patients with advanced malignant lymphoma. Twenty patients (median age, 46.5 years; range, 27-66 years) underwent RI-UCBT with a preparative regimen consisting of fludarabine 125 mg/m2 , melphalan 80 mg/m 2 , and 4 Gy of total body irradiation. The median infused total cell dose was 2.75 x 10(7)/kg (range, 2.3-3.4 x 10(7)/kg). Graft-versus-host disease (GVHD) prophylaxis was composed of cyclosporine or tacrolimus alone. Fifteen patients achieved primary neutrophil engraftment after a median of 20 days. Eight patients developed grade II to IV acute GVHD, and 2 developed chronic GVHD. Of the 16 patients with evaluable disease, 10 achieved a complete response. Primary disease recurred in 1 patient, and transplant-related mortality within 100 days occurred in 8 of 20 patients. The estimated 1-year probability of progression-free survival was 50%. These data suggest that RI-UCBT is a feasible option for patients with refractory lymphoma who lack an HLA-matched donor.  相似文献   
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Polymerization of phenylacetylenes (PAs) having various ortho-substituents were examined by using MoOCl4—n-Bu4Sn—EtOH (mole ratio 1:1:1) as catalyst. Phenylacetylenes with no or sterically small ortho-substituents did not polymerize in a living fashion. On the other hand, in the polymerization of phenylacetylenes having medium-sized substituents (e.g., CH3, Cl, Br, and iPr), the number-average molecular weights Mn of polymers increased in direct proportion to monomer consumption, while the polydispersity ratios were 1,2– 1,3, which is in favor of living polymerization. Further, monomers having bulky ortho-groups (CF3 and Me3Ge) exhibited excellent living nature with small polydispersity ratios of ≈ 1,1. Thus, it is concluded that not the electronic but the steric effect of the ortho-substituent is important to achieve living polymerization.  相似文献   
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Regulation of B cell fates by BCR signaling components   总被引:5,自引:0,他引:5  
Recent results obtained in mice harboring cytoplasmic mutations of Igalpha and/or Igbeta have reinforced the concept that the strength of BCR signaling is important for ensuring appropriate developmental outcomes as well as antigen-specific responses. To establish the optimal signaling intensity and duration, the BCR utilizes positive and negative regulatory molecules. Studies are beginning to reveal how these molecules maintain immunological homeostasis and tolerance.  相似文献   
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A neural network-based similarity index for clustering DNA microarray data   总被引:3,自引:0,他引:3  
A common approach to the analysis of gene expression data is to define clusters of genes that have similar expression. A critical step in cluster analysis is the determination of similarity between the expression levels of two genes. We introduce a neural network-based similarity index as a non-linear similarity index and compare the results with other proximity measures for Saccharomyces cerevisiae gene expression data. We show that the clusters obtained using Euclidean distance, correlation coefficients, and mutual information were not significantly different. The clusters formed with the neural network-based index were more in agreement with those defined by functional categories and common regulatory motifs.  相似文献   
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Renal glomerulogenesis in medaka fish, Oryzias latipes   总被引:2,自引:0,他引:2  
We provide an overview of glomerulogenesis in medaka from the embryo to the adult by means of in situ hybridization with the wt1 gene as a marker as well as histology and three-dimensional images. The pronephric glomus starts to develop in the intermediate mesoderm during early somitogenesis, is completed before hatching, and persists throughout the lifetime of the fish. Within 5 days after hatching, mesonephric glomerulus formation begins in the caudomedial end of the pronephric sinus and duct area. The number of glomeruli reaches approximately 200-300 in each kidney within 2 months after hatching. wt1 expression during nephron maturation served as a marker for the formation of the mesenchymal condensate and the nephrogenic body. Existence of mesenchymal condensates and persistence of wt1 expression in the adult kidney suggest that the mesonephros retains precursor cells that may be capable of contributing to neoglomerulogenesis during adulthood. Developmental Dynamics 237:2342-2352, 2008. (c) 2008 Wiley-Liss, Inc.  相似文献   
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Mice deficient in the B cell adaptor for phosphoinositide 3-kinase (BCAP) have reduced numbers of mature B lymphocytes, which show defects in cell survival and proliferation. We found here that the NF-kappa B (Rel) pathway was impaired in BCAP-deficient mature B cells and that NF-kappa B target genes, indispensable for cell survival and division, were not induced in response to B cell receptor (BCR) stimulation. Among the NF-kappa B (Rel) family, expression of c-Rel was specifically reduced in BCAP-deficient B cells. Retrovirus-mediated reintroduction of c-Rel restored the pool size of immunoglobulin (Ig)M(lo)IgD(hi) mature B cells in the spleen as well as proliferative responses to BCR stimulation. These results indicate BCAP is essential in the maintenance of mature B cells through functional coupling with c-Rel.  相似文献   
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