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排序方式: 共有838条查询结果,搜索用时 906 毫秒
831.
832.
Storb R; Deeg HJ; Thomas ED; Appelbaum FR; Buckner CD; Cheever MA; Clift RA; Doney KC; Flournoy N; Kennedy MS 《Blood》1985,66(3):698-702
Forty-eight patients with chronic myelocytic leukemia, aged 11 to 47, were treated with high-dose cyclophosphamide and fractionated total body irradiation, followed by infusion of marrow from HLA-identical siblings. They were randomized to receive either methotrexate (MTX) (n = 23) or cyclosporine (CSP) (n = 25) as postgrafting prophylaxis for graft-v-host disease (GVHD). All patients had evidence of sustained hematopoietic engraftment. Seventeen of the 25 patients receiving CSP and 17 of the 23 patients receiving MTX are alive between one and almost four (median, 1.7) years, with an actuarial survival rate at three years of 62% and 66%, respectively (P = .60). Also, with respect to most other parameters studied, the two drugs were identical. The probability of acute GVHD was .42 and .46, respectively (P = .70), that of chronic GVHD, .50 and .63 (P = .44), and that of death from transplant-related causes, .30 and .24 (P = .51). There were no differences in the speed of granulocyte and platelet engraftment (P = .82 and .94, respectively), and the duration of hospitalization was comparable (P = .58). Patients receiving MTX required red cell transfusions for a shorter period of time (P = .02), but had a slightly increased morbidity from early oral mucositis. The leukemia recurrence rates were comparable (P = .60). With the regimens used in this study, we conclude that CSP failed to reduce the incidence of GVHD and improve the survival of patients with chronic myelocytic leukemia when compared to results with standard MTX. 相似文献
833.
Busca A; Anasetti C; Anderson G; Appelbaum FR; Buckner CD; Doney K; Martin PJ; Petersdorf E; Sanders JE; Hansen JA 《Blood》1994,83(10):3077-3084
High-dose chemoradiotherapy followed by marrow transplantation from an HLA-matched sibling donor is curative for patients with acute leukemia. Autologous marrow transplantation has been used with success for some patients without such a sibling. Alternatively, the option of performing a transplant from an HLA-matched unrelated donor has been made possible by the recent development of large registries of HLA- typed volunteers. The purpose of this study was to compare the outcomes for patients with advanced leukemia treated by unrelated or autologous marrow transplantation. Forty-three patients with acute myeloid or lymphoid leukemia were transplanted from a closely HLA-matched unrelated donor. Results were compared with those of a disease-, disease-stage-, and age-matched cohort of 77 patients treated with autologous marrow transplantation at the same institution during the same period. Myeloid reconstitution with peripheral granulocyte counts greater than 10(9)/L was achieved in 93% of unrelated recipients and 70% of autologous recipients at a median of 24 and 36 days after transplantation, respectively (P = .0001). The cumulative proportions of patients discharged alive (79% v 77%) and times from transplant to first hospital discharge (35 v 34 days) were not different between unrelated and autologous recipients (P = .65). For patients transplanted in complete remission, relapse occurred after transplantation in 27% of the unrelated and in 55% of the autologous recipients (P = .08). For patients transplanted in relapse, the corresponding posttransplant relapse rates were 48% and 63%, respectively (P = .72). Forty percent of unrelated recipients and 28% of autologous recipients died in remission. Leukemia-free survivals were 33% for unrelated and 25% for autologous recipients transplanted in remission (P = .45), and 12% for unrelated and 5% for autologous recipients transplanted in relapse (P = .75). Unrelated donor transplants appear no less effective than autologous transplants to achieve long-term survival and may be more effective in eradicating leukemia in patients who have failed conventional chemotherapy. Further studies are warranted to assess the relative effectiveness of unrelated and autologous transplantation performed earlier in the course of the disease. 相似文献
834.
Furosemide inhibits regenerative cortical spreading depression in anaesthetized cats 总被引:2,自引:0,他引:2
SJ Read MI Smith CD Benham AJ Hunter AA Parsons 《Cephalalgia : an international journal of headache》1997,17(8):826-832
Ionic perturbations occur during cortical spreading depression (SD), a phenomenon implicated in migraine pathophysiology. We studied the effect of 0.2,2 and 20 mg kg−1 iv ( n =4) furosemide on cortical direct current (d.c.) potential, cerebrovascular laser Doppler flux (rCBFLDF ), artery diameter and NO concentration in the parietal cortex of the anaesthetized cat during repetitive SD. In vehicle treated animals ( n =4), SD activity was sustained for 50 1.8 min. However, duration of SD activity was significantly reduced when compared to vehicle to 39 6.6 ( n =4), 3.1 8.3 ( n =4) and 27.3 11.3 min ( n =4), at 0.2, 2 and 20 mg kg−1 iv furosemide respectively. It is hypothesized that the mechanism of inhibition of SD d.c. activity by furosemide may be through alterations in cortica ion buffering capacity or inhibition of cell swelling in neurones or glia. These mechanisms may represent potential novel drug targets in future migraine therapy. 相似文献
835.
Density gradient separation of peripheral blood stem cells: comparison of an automated cell processing device and manual methods 总被引:1,自引:0,他引:1
Peripheral blood stem cells were collected from normal donors by leukapheresis on a cell separator. The leukapheresis product contained 1.5 x 10(10) mononuclear cells (MNCs) and was divided into two aliquots that underwent either automated or manual density gradient separation with ficoll-hypaque and subsequent washing. In the automated process, recovery of MNCs was 85 percent, reduction in platelet content was 64 percent, and the final hematocrit (Hct) was less than 1 percent. The manual separation resulted in 76-percent MNC recovery, a 79-percent reduction in platelet content, and a final Hct of less than 1 percent. The purified MNCs were then placed in methylcellulose culture at a concentration of 4 x 10(5) MNCs per mL. Quadruplicate 1-mL aliquots were cultured, and colonies were counted and classified on Day 14. Comparison of automated and manual ficoll-hypaque separations demonstrated no differences in the total, erythroid, or granulocyte-macrophage colony numbers. The cell processor used is fast, reliable, uncomplicated, and provides a sterile product containing progenitor cells that are not adversely affected by the automated ficoll-hypaque separation. 相似文献
836.
837.
The matrix (MA) domain of the HIV-1 structural precursor Gag (PrGag) protein targets PrGag proteins to membrane assembly sites, and facilitates incorporation of envelope proteins into virions. To evaluate the specific requirements for the MA membrane-binding domain (MBD) in HIV-1 assembly and replication, we examined viruses in which MA was replaced by alternative MBDs. Results demonstrated that the pleckstrin homology domains of AKT protein kinase and phospholipase C delta1 efficiently directed the assembly and release of virus-like particles (VLPs) from cells expressing chimeric proteins. VLP assembly and release also were mediated in a phorbol ester-dependent fashion by the cysteine-rich binding domain of phosphokinase Cgamma. Although alternative MBDs promoted VLP assembly and release, the viruses were not infectious. Notably, PrGag processing was reduced, while cleavage of GagPol precursors resulted in the accumulation of Pol-derived intermediates within virions. Our results indicate that the HIV-1 assembly machinery is flexible with regard to its means of membrane association, but that alternative MBDs can interfere with the elaboration of infectious virus cores. 相似文献
838.
Mary-Powel Thomas BA Gabriela Ammann MPH CD Chinelo Onyebeke MPH Tanya K. Gomez MPH Samantha Lobis MPH Wenhui Li PhD Mary Huynh PhD 《分娩》2023,50(1):138-150