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51.
Autologous bone marrow transplants (BMTs) can repopulate the hematologic system of patients treated with marrow-ablative chemotherapy and/or radiotherapy. However, treatment of the bone marrow graft to eliminate residual tumor cells prior to reinfusion can delay the return of peripheral blood elements, presumably from damage to or loss of hematopoietic stem cells responsible for hematologic recovery. To develop a model predictive of hematologic recovery, we studied the progenitor cell contents of 4-hydroperoxycyclophosphamide (100 micrograms/mL)-purged bone marrow grafts of 40 consecutive patients undergoing autologous BMT at this center. Granulocyte-macrophage colonies (CFU-GM) were grown from all grafts after treatment with this chemotherapeutic agent, but erythroid (BFU-E) and mixed (CFU-GEMM) colonies were grown from only 44% and 33% of the grafts respectively. The recovery of CFU-GM after purging ranged from 0.07% to 23%. The logarithm of CFU-GM content of the treated grafts was linearly correlated with the time to recovery of peripheral blood leukocytes (r = -0.80), neutrophils (r = -0.79), reticulocytes (r = -0.60), and platelets (r = -0.66). The CFU-GM content of purged autologous bone marrow grafts may reflect the hematopoietic stem cell content of the grafts and thus predict the rate of hematologic recovery in patients undergoing autologous BMT.  相似文献   
52.
To assess the relative importance of the glycoprotein (GP) Ib binding domain and the RGDS binding site in platelet adhesion to isolated von Willebrand factor (vWF) and to collagen preincubated with vWF, we deleted the A1 domain yielding delta A1-vWF and introduced an aspartate- to-glycine substitution in the RGDS sequence by site-directed mutagenesis (RGGS-vWF). Recombinant delta A1-vWF and RGGS-vWF, purified from transfected baby hamster kidney cells, were compared with recombinant wild-type vWF (WT-vWF) in platelet adhesion under static and flow conditions. Purified mutants were coated on glass or on a collagen type III surface and exposed to circulating blood in a perfusion system. Platelet adhesion under static condition, under flow conditions, and in vWF-dependent adhesion to collagen has an absolute requirement for GPIb-vWF interaction. The GPIIb/IIIa-vWF interaction is required for adhesion to coated vWF under flow conditions. Under static condition and vWF-dependent adhesion to collagen, platelet adhesion to RGGS-vWF is similar as to WT-vWF, but platelet spreading and aggregation are abolished.  相似文献   
53.
Incubation of chronic myeloid leukemia (CML) marrow for 10 days in vitro causes a marked and selective loss of very primitive Philadelphia chromosome (Ph)+ as compared with Ph- progenitors. We have autografted 22 patients with CML (16 in first chronic phase [group 1] and 6 with more advanced disease [group 2]) with marrow treated in this way to facilitate restoration of Ph- hematopoiesis after intensive therapy. Hematologic recovery to greater than 0.5 x 10(9)/L neutrophils occurred in 16 patients, and to greater than 20 x 10(9)/L platelets in 15 of 21 evaluable patients at a median of 29 and 48 days postautograft, respectively. Regenerating marrow cells were 100% Ph- in 13 patients and 75% to 94% Ph- in 3. Between 4 and 36 months (median 12) postautograft, Ph+ cells became detectable in all but 1 (who died in remission) of the 13 patients who achieved complete cytogenetic remission. Four of 7 evaluable patients treated with low-dose interferon alpha were returned to complete cytogenetic remission. Thirteen group 1 patients (81%) are alive 1.0 to 5.7 years (median 2.6) after autografting: 4 in complete cytogenetic remission, 2 in hematologic remission, 6 in chronic phase, and 1 in myeloid blast phase. Three group 2 patients (50%) are alive at 2.6, 3.8, and 4.3 years after autografting: 1 in partial cytogenetic remission, 1 in chronic phase, and 1 in accelerated phase. Thus, autografts of cultured marrow can result in prolonged restoration of Ph- hematopoiesis for some patients with CML.  相似文献   
54.
Kickler  TS; Braine  HG; Ness  PM; Koester  A; Bias  W 《Blood》1983,61(2):238-242
Despite the use of HLA-matched platelets for alloimmunized recipients, transfusion failures occur. In order to reduce these failures, we investigated the use of a radiolabeled antiglobulin technique for platelet crossmatching. The principle of the test is that of an indirect Coombs test using 125I labeled goat anti-human IgG. Incompatibility is determined by calculating a radioactivity antiglobulin test (RAGT) index. Using this technique, we performed 89 crossmatches on 19 leukemic or aplastic patients who were refractory to random donor platelets and receiving varying degrees of HLA-matched platelets. Effectiveness of the transfusion was assessed from the posttransfusion corrected platelet count increment (CCI) determined at 1 and 20 hr. When the RAGT index was 1.9 or less, the mean CCI at 1 lhr was 17,570 +/- 7003/cu mm, n = 55. When the RAGT index was 2.0 or greater, the mean CCI was 4237 +/- 4100/cu mm, n = 34. At 20 hr when the RAGT index was 1.9 or less, the mean CCI was 8722 +/- 3143/cu mm, n = 33, and when the index was 2.0 or greater, the mean CCI was 571 +/- 1286/cu mm, n = 23. Using this technique, one false negative resulted. Nine positive crossmatches with good increments at 1 hr were found; at 20 hr, however, the survival of these units was zero. These data suggest that this method is a useful adjunct in the selection of platelets in the refractory patient.  相似文献   
55.
We used an in vitro measure of drug activity to predict the efficacy of ex vivo purging of leukemic cells from autologous bone marrow grafts. We previously found that the myeloid progenitor cell (CFU-GM) content of the marrow grafts after ex vivo purging with 4- hydroperoxycyclophosphamide (4-HC) correlates with time to hematologic recovery after autologous bone marrow transplantation in patients with acute nonlymphoblastic leukemia. We observed that variable red blood cell concentration of the bone marrow incubation mixture results in differential cytotoxic activity of 4-HC. The CFU-GM content of the graft after the ex vivo treatment is a measure of this 4-HC activity. We analyzed the disease-free survival of 45 patients with acute nonlymphoblastic leukemia undergoing autologous bone marrow transplantation with 4-HC purged grafts. Patients who relapsed after transplantation had 4.2 +/- 1.1% of graft CFU-GM surviving the ex vivo purge, compared with 1.1 +/- 0.4% for patients who achieved a sustained remission (P = .06). Twenty-three patients with a CFU-GM content after 4-HC purging of greater than 1% of the pretreatment value had an actuarial disease-free survival of 12%, compared to 36% for 22 patients with a less than or equal to 1% CFU-GM content after purging (P = .006). Therefore, percent CFU-GM survival as a measure of 4-HC cytotoxicity identified a group of patients with insufficient purging. Although no randomized clinical trials have documented the need for ex vivo purging, our results suggest that effective bone marrow purging is important for the optimal application of autologous transplantation in the treatment of acute nonlymphoblastic leukemia.  相似文献   
56.

Background  

Shoulder impingement syndrome is a common musculoskeletal complaint leading to significant reduction of health and disability. Physiotherapy is often the first choice of treatment although its effectiveness is still under debate. Systematic reviews in this field highlight the need for more high quality trials to investigate the effectiveness of physiotherapy interventions in patients with subacromial impingement syndrome.  相似文献   
57.
Non-invasive breath tests can serve as valuable diagnostic tools in medicine as they can determine particular enzymatic and metabolic functions in vivo. However, methodological pitfalls have limited the actual clinical application of those tests till today. A major challenge of non-invasive breath tests has remained the provision of individually reliable test results. To overcome these limitations, a better understanding of breath kinetics during non-invasive breaths tests is essential. This analysis compares the breath recovery of a 13C-methacetin breath test with the actual serum kinetics of the substrate. It is shown, that breath and serum kinetics of the same test are significantly different over a period of 60 minutes. The recovery of the tracer 13CO2 in breath seems to be significantly delayed due to intermediate storage in the bicarbonate pool. This has to be taken into account for the application of non-invasive breath test protocols. Otherwise, breath tests might display bicarbonate kinetics despite the metabolic capacity of the particular target enzyme.  相似文献   
58.
59.

Background  

Pregnancy-related pelvic girdle and/or low back pain is a controversial syndrome because insight in etiology and prognosis is lacking. The controversy relates to factors eliciting pain and some prognostic factors such as the interpretation of pain at the symphysis. Recent research about treatment strategies also reflects those various opinions, in fact suggesting there is professional uncertainty about the optimal approach. Currently, physiotherapists often prescribe a pain-contingent treatment regime of relative rest and avoiding several day-to-day activities. Additionally, treatment more often includes an exercise program to guide rectification of the muscle imbalance and alignment of the pelvic girdle. Effectiveness of those interventions is not proven and the majority of the studies are methodologically flawed. Investigators draw particular attention to biomedical factors but there is growing evidence that important prognostic issues such as biopsychosocial factors appear to be even more important as point of action in a treatment program.  相似文献   
60.
Endoxin antagonist lessens myocardial ischemia reperfusion injury@柯永胜$Department of Cardiology, Yijishan Hospital, Wannan Medical College, Wuhu, 241001 China @王德国$Department of Cardiology, Yijishan Hospital, Wannan Medical College, Wuhu, 241001 C  相似文献   
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