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61.
From March 1988 to March 1991, 19 French bone marrow transplant (BMT) centers participated in a prospective randomized trial comparing two conditioning regimens for patients with chronic myeloid leukemia transplanted in first chronic phase with an HLA identical sibling donor. A total of 120 consecutive patients were randomized to receive either 120 mg/kg of cyclophosphamide followed by total body irradiation (CY-TBI; n = 55) or 16 mg/kg of busulfan followed by 120 mg/kg of CY (BU-CY; n = 65). Two different TBI regimens were used. Thirteen patients received a 10-Gy single-dose TBI (SDTBI), and 42 received a fractionated TBI (FTBI). Median time between diagnosis and BMT was 315 days. Overall 5-year actuarial survival was 62.9% (65.8% +/- 12.5% for CY-TBI and 60.6 +/- 11.7% for BU-CY; P = .5), and overall disease-free survival was 55% (51% +/- 14% for CY-TBI and 59.1% +/- 11.8% for BU-CY; P = .75). All patients conditioned with CY-TBI experienced sustained engraftment; in contrast, 4 of 65 patients conditioned with BU-CY rejected the graft (P = .18). There was no significant statistical difference between the two groups regarding transplant-related mortality (29% for CY-TBI and 38% for BU-CY; P = .44). So far, with a median follow up of 42 months, 11 patients have relapsed; 9 relapses occurred after CY-TBI, mostly after FTBI (8 of 9) and 2 after BU-CY (P = .02). The actuarial risk of relapse was 4.4% +/- 6.7% after BU-CY, 11.1% +/- 20.8% after SDTBI, and 31.3% +/- 18.1% after FTBI (P = .039). In addition, independently of the conditioning regimen, the increase of posttransplant immunosuppression in 16 patients with an anti- interleukin-2 receptor monoclonal antibody (MoAb) in addition to a short course of methotrexate and cyclosporine was shown to increase the actuarial risk of relapse (57% +/- 30% with MoAb v 9% +/- 7.3% without MoAb; P = .001). We conclude that BU is an acceptable alternative to TBI for patients with chronic myeloid leukemia in first chronic phase receiving BMT from HLA identical sibling donors. Both BU-CY and CY-TBI regimens gave similar transplant-related mortality, and the antileukemic efficiency of BU-CY regimen was either similar or even higher than that of CY-TBI.  相似文献   
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63.
The partial characterization and expression of the C1q receptor (C1q-R) in relation to other complement receptors present on the surface of neutrophils has been examined, as well as the effects of free C1q on cell function. A polyclonal anti-C1q-R antibody recognizes a 68-kD neutrophil surface protein. C1q-R expression was not upregulated upon warming, priming, or exposure to FMLP, but decreased after exposure to phorbol myristate acetate (PMA), because of shedding of the receptor into the extracellular medium, as detected by enzyme-linked immunosorbent assay. CR3 and CR1 expression was upregulated from intracellular pools after cell stimulation by PMA. No evidence of intracellular pools of C1q-R was found, as assessed by immunoblotting of subcellular fractions. But C1q-R appeared to be expressed early in cell differentiation, was detected on undifferentiated HL-60 cells, and like CR3 expression, increased upon 5 days differentiation towards a neutrophil lineage. However, C1q-R expression decreased upon additional culture, whereas CR3 expression continued to increase. A large variation in the percentage of peripheral cells expressing C1q receptors in donors was observed, ranging from 13% to 100%, contrasting with CR3 receptors that exhibited less variability. Interactions between free monomeric C1q and neutrophils were also studied. Incubation of stimulated neutrophils with 10 to 100 micrograms/mL C1q resulted in a further increase in CR3 expression and adherence to albumin-coated surfaces. Staphylococci opsonized with low quantities of C1q (0.1 to 1 microgram/mL) mediated a moderate and sustained respiratory burst in neutrophils, whereas a burst of similar magnitude was generated only with free C1q at concentrations 10- to 100-fold higher. Stimulation was only partially inhibited if cells were first treated with anti-C1q-R antibody, suggesting other C1q binding proteins may be present on the cell surface. In summary, neutrophil C1q receptor is approximately 68-kD, exhibits varying expression on different subjects, and is not upregulated from intracellular stores on exposure to soluble stimuli. Stimulated, but not resting, neutrophils selectively respond to raised levels of free C1q, resulting in altered cell function and enhanced CR3 receptor expression. These studies thus suggest complex roles for C1q in neutrophil function.  相似文献   
64.
Kunicki  TJ; Pidard  D; Rosa  JP; Nurden  AT 《Blood》1981,58(2):268-278
Triton X-100 soluble proteins from 125I-labeled human platelets were studied by crossed immunoelectrophoresis employing a multispecific rabbit antibody raised against whole normal platelets. Emphasis was placed upon an analysis of immunoprecipitates containing 125I-labeled major membrane glycoproteins, and in particular, a prominent immunoprecipitate containing a glycoprotein antigen (s) previously designated as protein 16. SDS-polyacrylamide gel electrophoresis of protein 16 precipitated by a monospecific alloantibody. IgG L . . . , confirmed the presence of both glycoproteins IIb and IIIa. 125I-IgG L . . . , at concentration below that capable of precipitating protein 16 by itself, bound specifically to the precipitate containing protein 16 produced by the multispecific rabbit antibody. No other precipitates formed by the rabbit antibody contained either glycoprotein IIb or IIIa. When platelet proteins, incubated with optimum concentrations of ethylenediamine tetraacetic acid (EDTA) or ethyleneglycol bis (B- aminoethylether) NN1-tetraacetic acid (EGTA), were electrophoresed against the rabbit antibody, previously unobserved immunoprecipitates that contained either free glycoprotein IIb or free glycoprotein IIIa were detected. Upon readdition of excess Ca++, but not Mg++, to the same protein samples, a single immunoprecipitate containing both glycoproteins was once again observed. It is thus demonstrated that glycoproteins IIb and IIIa can form Ca++-dependent complexes (protein 16) in Triton X-100 extracts of normal platelets. The potential significance of the reversible association of these glycoproteins to normal platelet function is discussed.  相似文献   
65.
High-dose cytarabine (ara-c) may overcome cytarabine resistance in leukemic blasts. It has been used as a successful salvage and in postremission therapy but not as initial induction treatment. Patients aged 15 to 60 years, presenting with newly diagnosed acute myeloid leukemia (AML) were randomized to receive either high-dose cytarabine, 3 g/m2 12 hourly on days 1, 3, 5, and 7 for 8 doses, daunorubicin 50 mg/m2 days 1 to 3, etoposide 75 mg/m2 days 1 to 7, (HIDAC-3-7) or standard dose cytarabine 100 mg/m2 continuous intravenous infusion for 7 days with daunorubicin and etoposide at the same dose and schedule as above (7-3-7). Patients could receive a second or third induction course if complete remission (CR) was not achieved. All patients received the same postinduction consolidation therapy (5-2-5) for 2 courses. Eligible patients had no prior chemotherapy or myelodysplastic disease. Patients have been followed for a median of 4.5 years. Of 301 patients treated, complete response (CR) was achieved in 71% with HIDAC- 3-7 and 74% with 7-3-7. For patients in CR, the estimated median remission duration was 45 months with HIDAC-3-7 and 12 months with 7-3- 7 (P = .0005 univariate analysis, P = .0004 multivariate analysis). The estimated percentage of patients relapse free 5 years after achieving a CR was 49% on HIDAC-3-7 and 24% on 7-3-7. Patients in CR tended to survive longer with HIDAC-3-7 but there were no overall survival differences between the two arms. HIDAC-3-7 was associated with significantly more toxicity in induction with more leukopenia, thrombocytopenia, nausea, and vomiting and eye toxicity (all P < .001) but a similar incidence of severe central nervous system and cerebellar toxicity compared to 7-3-7. The consolidation treatment was the same in both arms but caused significantly more leukopenia and thrombocytopenia in patients previously treated with HIDAC-3-7 induction (P < .0001). We conclude that a dose-effect exists for cytarabine in AML and that HIDAC- 3-7 prolongs remission duration and disease-free survival and is tolerable when used as initial induction therapy in patients with de novo AML.  相似文献   
66.
67.
Temporal arteritis: a 25-year epidemiologic, clinical, and pathologic study   总被引:20,自引:0,他引:20  
Among the population of Olmsted County, Minnesota, 42 patients with temporal arteritis were identified during a 25-year period. The average annual incidence per 100 000 population aged 50 and older rose from 5.1 in 1950-1959 to 17.4 in 1970-1974. The prevalence of patients with a history of the diagnosis of temporal arteritis on 1 January 1975 was 133 per 100 000 population aged 50 and older. All patients received corticosteroid therapy for a range of 1 to 77 months (median, 7 months). Relapses in 10 of 11 patients were associated with corticosteroid reduction. The majority of patients recovered fully and were followed off corticosteroids for 10 months to 19 years (median, 5 years). Temporal arteritis had no significant effect on survival. Vertebral compression fractures and myopathy were the most serious complications of therapy. The presence of giant cells in biopsies was in part related to the number of sections examined, and their presence had no apparent influence on the clinical course.  相似文献   
68.
Sixty-three patients with high tumor mass multiple myeloma were treated with high-dose chemotherapy and total body irradiation supported by autologous blood stem cell transplantation. After high-dose therapy, they were monitored for a median of 44 months. Seven patients died early from toxicity. All the other patients, including those whose disease was resistant to previous therapies, showed a tumor mass reduction. At 6 months postengraftment, 40 (71%) of the surviving patients had minimal residual disease and 11 (20%) were in apparent complete remission. During follow-up, 25 out of the 63 (39%) patients relapsed and 16 of these died; 31 (49%) had a sustained remission. The median overall and event-free survival times after transplantation were 59 and 43 months, respectively. The initial serum beta 2-microglobulin value (> or < 2.8 mg/L) and length of previous therapy (> or < 6 courses of chemotherapy) were the only significant prognostic factors. In all surviving patients, blood stem cell autograft provided satisfactory and sustained haematopoietic reconstitution most often within 15 days. High dose chemoradiotherapy followed by autologous blood stem cell transplantation is thus an important therapeutic option for young patients with aggressive multiple myeloma.  相似文献   
69.
A prospective, randomized trial was initiated in adult acute lymphoblastic leukemia (ALL) to compare (1) disease-free survival (DFS) after allogeneic or autologous bone marrow transplantation (BMT) and (2) the relapse rate of patients treated with or without interleukin-2 (IL-2) after autologous BMT. A total of 135 previously untreated patients, aged under 55 years, received the Berlin-Frankfurt-Muster (BFM) induction regimen: 126 patients (93%), of which 120 were HLA- typed, achieved complete remission (CR). According to this genetic randomization, patients with (n = 43) or without an HLA-identical sibling (n = 77) were to receive allogeneic or autologous BMT, respectively. The 3-year post-CR probability of DFS was significantly higher in the HLA-identical sibling group than in the non-HLA-identical sibling group (68% v 26%; P < .001). Eligible patients were randomized to receive (n = 30) or not to receive (n = 30) IL-2 after autologous BMT: the 3-year post-BMT probability of continuous CR was similar in both groups (29% v 27%, respectively). We conclude that, in ALL, early allogeneic BMT after the BFM induction regimen is an effective consolidation treatment and that IL-2 does not decrease the high relapse rate observed after autologous BMT.  相似文献   
70.
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