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Beta-thalassemia major (TM) is caused by any of approximately 150 mutations within the beta-globin gene. To establish the degree of chimerism after bone marrow transplantation (BMT), we have performed molecular analysis of beta-globin mutations in 14 patients with TM over a period of 10 years. All patients underwent T cell-depleted allogeneic BMT from HLA-identical related donors, using either in vitro T-cell depletion with CAMPATH 1M and complement or in vivo depletion using CAMPATH 1G in the bone marrow collection bag. To date, at different time periods after BMT, seven patients have some degree of chimerism; six of these patients, all blood transfusion-independent, have donor cells in the range of 70% to 95%, with stable mixed chimerism (MC). The seventh patient has less than 10% donor cells with, surprisingly, only minimal transfusion requirements. The detection of beta-globin gene point mutation, as used here, is a highly specific and sensitive marker for engraftment and MC in patients with thalassemia. In light of its specificity, the method is applicable in all cases of TM, as it is independent of sex and other non-globin-related DNA markers. The high incidence of MC found in our patients may be a consequence of the pre- BMT T-cell depletion. Because MC was associated with transfusion independence, complete eradication of residual host cells for effective treatment of TM and possibly other genetic diseases may prove not to be essential.  相似文献   
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The synthesis and structure-activity relationships of C-terminal octapeptide analogues of anaphylatoxin C5a have been studied. The introduction of hydrophobic amino acids into the N-acetylated native octapeptide (N-Ac-His-Lys-Asp-Met-Gln-Leu-Gly-Arg-OH) (1) has led to an analogue with 100 times more activity than the native octapeptide in inhibiting the binding of 125I-labeled anaphylatoxin C5a to human neutrophil membrane receptors. The observed apparent binding Ki's for the compounds (8-10) are in the range of 1-3 microM, and they possess nearly full agonist activity, despite the fact that these analogues are one-eighth or -ninth the size of the natural ligand anaphylatoxin C5a.  相似文献   
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In 30 patients on chronic haemodialysis treatment the platelet activity and function were studied before and during antiplatelet therapy with alpha-tocopherol and sulphinpyrazone. In both kinds of treatment a significant decrease of ADP-induced and spontaneous aggregation was observed. Sulphinpyrazone exerts an inhibitory effect not only on platelet aggregation but also on platelet factor 3 and provokes a significant prolongation of the bleeding time.  相似文献   
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Fusion between spleen cells from an autoimmune NZB/NZW mouse and the Balb/c drugresistant MPC-11 myeloma resulted in the formation of a hybridoma-secreting RNA-specific IgG-3 antibody and the parental IgG-2b myeloma. Analysis of the mixed immunoglobulin assembly products made by the hybridoma cells showed efficient pairing of IgG-2b and IgG-3 heavy chains and did not show a marked preferential assembly of the homologous heavy and light chains. Partial purification of the anti-RNA antibody from the mixed assembly products was achieved by utilizing an antigen affinity column (RNA-Sepharose). The use of a heavy chain-specific affinity column (anti-IgG-2b-Sepharose) increased the purity of the desired antibody, but parental light chains were still present after this step. A complete purification of the RNA-binding protein could be achieved by papain cleavage of the total IgG fraction and binding of the resulting Fab fragments to RNA-Sepharose. This procedure may, therefore, be employed as a general method for purifying antibodies from hybridomas that continue to produce their parental myeloma chains.  相似文献   
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Activation or suppression of intracellular signaling via the mitogen-activated protein kinase (MAPK) family has been linked to expression of matrix metalloproteinases (MMP) in experimental models, but this association has not been demonstrated in clinical material. The objective of this study was to investigate the possible association between expression and activity of MMP, expression of the MMP inducer EMMPRIN, and the expression (level) and phosphorylation status (activity) of the extracellular-regulated kinase (ERK), c-Jun amino-terminal kinase (JNK) and high osmolarity glycerol response kinase (p38) in effusions from patients diagnosed with serous ovarian carcinoma. MAPK level and activity were studied in 55 effusions using immunoblotting. MMP-1, MMP-2, MMP-9 and EMMPRIN expression was studied using immunocytochemistry (ICC) and mRNA in situ hybridization (ISH). The gelatinolytic activity of MMP-2 and MMP-9 was measured by zymography. ERK and phospho-ERK (p-ERK) were detected in 54/55 (98%) and 50/55 (91%) specimens, respectively. JNK and p-JNK were detected in 53/55 (96%) and 38/55 (69%) specimens, respectively. p38 was expressed in 54/55 (98%) specimens, and its phosphorylated form was found in 51/55 (92%). MMP-2 mRNA expression (P=0.048), protein expression (P=0.046) and gelatinolytic activity (P=0.039) correlated with ERK phosphorylative activity. MMP-2 activity also correlated with p38 activity (P=0.017). MMP-9 protein expression correlated with phosphorylation of p38 (P=0.046), but enzyme activity showed inverse relationship with both p-ERK (P=0.05) and p-p38 (P=0.033) expression. EMMPRIN expression correlated with MMP-1 (P<0.001), MMP-2 (P=0.042) and MMP-9 (P=0.029) expression, as well as with ERK activity (P=0.001). Our results present the first evidence of a possible link between MAPK signaling and MMP expression and activity in vivo. These data may expand our understanding regarding the mechanisms by which MMP synthesis is regulated in effusions and possibly affect treatment strategies for this form of malignancy. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
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BackgroundHealth literacy, the ability to access, understand, evaluate and apply health information, was found to contribute to positive health outcomes, possibly via promoting healthy behaviours. However, the specific pathways linking different health literacy skills to health and well‐being have remained unclear.MethodsA cross‐sectional survey with structural questionnaires was administered among 2236 adults in Hong Kong (mean age = 46.10 ± 19.05). Health literacy was measured by HLS‐Asian‐47. Participants'' physical conditions and subjective well‐being were predicted by health literacy and health behaviours with structural modelling path analysis.ResultsHealth literacy in finding and understanding information showed a direct effect on enhancing physical health, while applying information capacity had an indirect positive effect via promoting health behaviours, which was moderated by sex. Only among women, this indirect effect predicting fewer physical symptoms and better well‐being was significant.ConclusionsDifferent health literacy dimensions showed distinct direct and indirect pathways in influencing health for men and women. Based on the findings, skill trainings should be developed to enhance both gender''s abilities of finding and understanding health information, while the ability of applying health information should also be improved for modifying lifestyle and promoting health, particularly for women.Patient or Public ContributionTwo thousand and two hundred thirty‐six adults from different districts of Hong Kong participated in the study, and responded to questions on health literacy, behaviours and health status.  相似文献   
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The purpose of this study was to define the treatment of choice (partial laryngectomy vs radiotherapy) in the early stage of supraglottic squamous cell cancer (ESSC). One hundred and fifteen patients with ESSC were treated with either partial laryngectomy (25 patients) or with radiotherapy(90 patients) between January 1984 and December 1996. All patients had a follow-up of over ¶29 months. Radiotherapy (RT) had a local control rate of 79%, which increased to 90% with salvage surgery, and a high larynx preservation rate (83%). Partial laryngectomy (PL) offered a better initial local control rate of 84%, which increased to 88% with salvage surgery, and functional results were also good (80%). No statistically significant differences were found between RT and PL. RT was less costly, showed better suitability for treatment, produced moderate morbidity and sequelae, and local recurrence was easier to rescue. However, it is a once-only application technique. PL showed higher immediate postoperative morbidity, higher cost and lower suitability for treatment but had fewer sequelae, offered the best initial local control and is multi-applicable. No clear oncological arguments were found in our series to define whether PL or RT is the treatment of choice for ESSC. Both are effective therapies. Secondary factors such as suitability for treatment, morbidity, cost and applicability should be individually evaluated when choosing the type of treatment. As the laser endoscopic approach decreases morbidity and costs and makes the condition more suitable for treatment, it could be the treatment of choice for ESSC, in cases where local tumoral extent and larynx exposure allow radical excision.  相似文献   
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