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61.
We examined the effects of varying incubation conditions on the in vitro activity of 4-hydroperoxycyclophosphamide (4HC). 4HC activity against CFU-GM and against the K562 tumor cell line decreased with increasing the RBC concentration of the incubation mixture. Increasing the concentration of nucleated bone marrow cells in the incubation mixture also decreased the 4HC activity. Evaluation of 53 consecutive patients undergoing autologous bone marrow transplantation (BMT) revealed that the incubation RBC concentration during clinical purging showed a similar effect on CFU-GM recovery. Aldehyde dehydrogenase content of RBCs and nucleated marrow cells appears to be the cause of the inhibition of 4HC activity. Although there was no difference in individual CFU-GM sensitivity to 4HC among normals, previously treated patients undergoing autologous BMT showed significant variability in CFU-GM sensitivity to 4HC. The combined effects of incubation RBC concentration and individual patient 4HC sensitivity appear to account for most of the variability in CFU-GM recovery and speed of hematologic recovery after clinical purging with 4HC.  相似文献   
62.
Enterobacteria, in particular Klebsiella spp., have been implicated in the aetiopathogenesis of ankylosing spondylitis. A comprehensive examination of the faecal flora of 82 patients with ankylosing spondylitis, either primary (67), or in association with inflammatory bowel disease (4), reactive arthritis (6) or psoriatic arthritis (5), was performed and compared with that of a control population (36) of healthy individuals. The range of flora identified was similar in both populations and there was no increased isolation rate of Klebsiella or other proposed arthritogenic organism in those with spondyloarthropathy. In those patients in whom Klebsiella was identified, its presence was not related to disease activity, the erythrocyte sedimentation rate or C-reactive protein.   相似文献   
63.
Cherepakhin  V; Baird  SM; Meisenholder  GW; Kipps  TJ 《Blood》1993,82(10):3141-3147
Patients with B-cell chronic lymphocytic leukemia (CLL) infrequently may develop high-grade B-cell lymphoma, or Richter's syndrome lymphoma (RS lymphoma). Such lymphomas differ from the original leukemia in both histology and clinical behavior. Studies seeking to define the clonal relationship between the cells of the two malignancies in any one patient have yielded conflicting reports. We examined the clonal relationship between the early and late neoplastic cells of a patient who underwent Richter's transformation. In contrast to the original leukemia cells, the secondary high-grade lymphoma was CD5-. However, both the leukemia cells and the evolved RS lymphoma expressed surface IgM lambda reactive with Lc1, a murine monoclonal antibody specific for a supratypic cross-reactive idiotype encoded by a subset of human Ig variable region genes of the VH4 subgroup. Nucleic acid sequence analyses of the heavy and light chain variable region genes expressed by both leukemia and lymphoma cells show that the CD5- B-cell lymphoma constitutes a clonal expansion of mutant cells derived from the original CD5+ B-cell leukemia. Moreover, certain sets of somatic mutations distinguish the Ig variable region genes used by RS lymphoma from those expressed by the CLL B cells. This is the first study to establish the clonal relationship between CLL and RS lymphoma through primary structural analyses of the expressed Ig genes.  相似文献   
64.
A semiautomated saline wash procedure using a blood cell processor was evaluated as a technique for removing plasma from platelet concentrates. In vitro studies demonstrated 92 to 99.6 percent (mean, 96%) removal of total plasma protein (n = 30) with 84 to 97 percent (mean, 90.8%) platelet recovery (n = 28) in post-wash units. Post-wash pH values changed by +0.2 to -0.86 (mean, -0.47) (n = 30); the level of recovery from hypotonic shock was 69 to 97 percent (mean, 86%) (n = 11) of pre-wash units; weighted morphology scores decreased from a mean of 248 to 223 (n = 9). Aggregation response to arachidonic acid, collagen, and adenosine diphosphate plus epinephrine showed essentially no change following the wash procedure, and electron microscopy demonstrated slight morphologic alteration. Autologous platelets labeled with indium-111 demonstrated 43 +/- 20 percent recovery (n = 11) for washed units, compared to 41 +/- 10 percent for control unwashed units (n = 5); mean survivals were 140 +/- 41 hours (n = 11) for washed platelets and 185 +/- 28 hours for unwashed units (n = 5). Thirteen alloimmunized patients receiving 55 washed platelet concentrates demonstrated a mean 1- to 4-hour corrected count increment of 3.99 X 10(3) per microliter, compared to 3.02 X 10(3) per microliter for 77 unwashed platelet units given to the same patients. This study documents that platelet concentrates maintain viability and efficacy following a semiautomated saline wash method using the Cobe 2991 Blood Cell Processor, a technique that may be helpful for patients who require plasma-depleted platelet transfusions.  相似文献   
65.
We retrospectively examined 154 adults to ascertain the frequency, site of and pre-disposing factors for biliary strictures after liver transplantation, as well as their management and clinical outcome. Twenty patients (12.5%) were identified with biliary strictures; 16 were non-anastomotic and four were anastomotic strictures. The median time from transplantation to stricture diagnosis was 17 weeks (range 3–366). Of the 16 non-anastomotic strictures, six were intrahepatic, eight hilar and two extrahepatic (donor bile duct). A control group (n = 32) of patients transplanted immediately before and after index cases was used to examine for correlates in patients with non-anastomotic strictures. At the time of diagnosis in the non-anastomotic index cases, there was a higher incidence of: (i) biliary sludge (63 vs 0%; P< 0.001); and (ii) clinical cholangitis (75 vs 0%; P< 0.001) compared with controls. Primary sclerosing cholangitis was more often the diagnosis in index patients with non-anastomotic strictures compared with controls (31 vs 9%; P<0.05). There were no differences between index patients and controls (non-anastomotic group) in ABO blood group non-identity, cold allograft ischaemia time, use of OKT3 (murine monoclonal antibody to CD3) and hepatic artery thrombosis. Of 15 patients treated with balloon dilatation, seven required stent insertion although none have required surgery. As determined by liver function tests, there was evidence of persisting graft dysfunction in index patients compared with controls (SAP 381 vs 112 U/L, P< 0.001; GGT 529 vs 80 U/L, P< 0.001), but there was no difference in survival during a median follow-up time of 16 months (range: 3–48 months) from stricture diagnosis. In conclusion, biliary strictures tend to occur within 6 months of transplantation and are an important cause of ongoing graft dysfunction. Non-anastomotic strictures were more common in patients requiring transplantation for primary sclerosing cholangitis.  相似文献   
66.
Pulmonary hypertension is now recognized to be a rare association of liver disease and portal hypertension. This report describes the slow resolution of symptomatic pulmonary hypertension in a 33-year-old woman with cirrhosis who underwent isolated liver transplantation. The patient survived the surgery and perioperative period without significant haemodynamic compromise. After liver transplantation, the patient was monitored with regular Doppler echocardiography. By 27 months the pulmonary hypertension had almost completely resolved. This observation is important, as it suggests that patients with severe pulmonary hypertension who survive the perioperative period may have an excellent outcome, although resolution may be slow.  相似文献   
67.
Kanz  L; Lohr  GW; Fauser  AA 《Blood》1986,68(5):991-995
Conditioned medium derived from peripheral mononuclear low-density cells stimulated with phytohemagglutinin (PHA) supports the growth of noncommitted hematopoietic progenitors from marrow and peripheral blood cells. These immature progenitors (CFU-GEMM) can be identified in culture as multilineage hematopoietic colonies containing erythroblasts, eosinophilic, basophilic and neutrophilic granulocytes, megakaryocytes, macrophages, and T and B lymphocytes. In this report, we describe the effect of lymphokines released from purified T lymphocyte preparations of helper (T4) and suppressor/cytotoxic (T8) phenotype derived from peripheral blood on the growth of multilineage hematopoietic colonies and megakaryocytic colonies. It was found that PHA-stimulated lymphocytes of T4 phenotype and, to a lesser extent, of T8 phenotype elaborate lymphokine(s) that support the growth and development of multilineage colonies (CFU-GEMM), granulopoietic colonies (CFU-C), erythroid bursts (BFU-E) and megakaryocytic colonies (CFU-M) by nonadherent and T cell-depleted bone marrow cells.  相似文献   
68.
Cytomegalovirus (CMV) infection was detected in 65 of 143 (45%) autologous bone marrow transplant (BMT) patients. CMV pneumonitis occurred in only 2% of the patients and CMV retinitis occurred in none. Infection occurred in half of the 40 initially seronegative patients and 47% of the 94 initially seropositive patients. Among initially seropositive patients, platelet recovery was slower in infected patients than in those not infected (97 v 35 days median, P = .003), and neutrophil recovery was slightly delayed in infected patients (31 days v 24 days, P = .02). Although the incidence of CMV infection was comparable in autologous and allogeneic BMT patients, CMV pneumonitis was less frequent in autologous BMT patients (2% v 12%, P less than .001). The risk for CMV pneumonitis in autologous BMT patients was comparable with that in allogeneic BMT patients without graft-v-host disease (GVHD) (2% v 6%), but significantly lower than the risk in allogeneic BMT patients with GVHD (2% v 23%, P less than .001).  相似文献   
69.
We performed a phase I trial of recombinant human interleukin-11 (rhIL- 11) in women with breast cancer. Cohorts of three to five women were accrued to five dosage levels of rhIL-11 (10, 25, 50, 75, and 100 micrograms/kg/d). rhIL-11 alone was administered by a daily subcutaneous injection for 14 days during a 28-day prechemotherapy "cycle 0." Patients (pts) subsequently received up to four 28-day cycles of cyclophosphamide (1,500 mg/m2) and doxorubicin (60 mg/m2) chemotherapy followed by rhIL-11 at their assigned dose (days 3 through 14). Sixteen pts (13 stage IV, 3 stage IIIB) were accrued to this study. Median age was 53 years and median Eastern Cooperative Oncology Group Performance Status was 0. A grade 3 neurologic event was seen in 1 pt at 100 micrograms/kg. Because of the degree of grade 2 constitutional symptoms (myalgias/arthralgias and fatigue) at 75 micrograms/kg, dose escalation was stopped and 75 micrograms/kg was the maximally tolerated dose. No other grade 3 or 4 adverse events related to rhIL-11 were seen. The administration of rhIL-11 was not associated with fever. Reversible grade 2 fatigue and myalgias/arthralgias were seen in all pts at 75 micrograms/kg. Weight gain of 3% to 5% associated with edema was seen at doses > 10 micrograms/kg but a capillary leak syndrome was not seen. rhIL-11 alone was associated with a mean 76%, 93%, 108%, and 185% increase in platelet counts at doses of 10, 25, 50, and 75 micrograms/kg, respectively. No significant changes in leukocytes were seen. A mean 19% decrease in hematocrit was observed. Acute-phase proteins increased with treatment at all doses. Compared with patients at the 10 micrograms/kg dose, patients receiving doses > or = 25 micrograms/kg experienced less thrombocytopenia in the first two cycles of chemotherapy. We conclude that rhIL-11 has thrombopoietic activity at all doses studied, is well tolerated at doses of 10, 25, and 50 micrograms/kg, and at doses > or = 25 micrograms/kg has the potential to reduce chemotherapy-induced thrombocytopenia in this model.  相似文献   
70.
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