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531.
The effects of peripheral blood adherent cells from normal donors on human myeloid leukemic cluster growth in agar were studied. A prior co- incubation of nonadherent leukemic cells with adherent cell monolayers from 9 out of 10 donors in liquid cultures over a 4-hr period was sufficient to reduce subsequent leukemic growth in semisolid agar cultures. Inhibition was seen with adherent to leukemic cell ratios of as low as 0.5:1. Conversely, identical numbers of adherent cells in agar cultures but separated from the leukemic cells enhanced growth more than the cultures containing human placental conditioned media alone. Because leukemic cell exposure to adherent cells was brief, a cytotoxic mechanism appeared likely; however, this could not be detected by 51Cr release. Human peripheral blood adherent cells not activated by any in vitro mechanism suppress clonal growth of human myeloid leukemic cells by a mechanism requiring cell to cell contact. Examination of the inhibition of clonal growth appears to be more sensitive than 51Cr release as an indicator of adherent cell effects on myeloid leukemia.  相似文献   
532.
Antin  JH; Smith  BR; Holmes  W; Rosenthal  DS 《Blood》1988,72(2):705-713
We performed a phase I/II study of the administration of recombinant human granulocyte-macrophage colony-stimulating factor (GM-CSF) to patients with aplastic anemia or myelodysplastic syndrome. Doses ranging from 15 to 480 micrograms/m2 were administered as a one-hour or four-hour intravenous infusion daily for 7 days or as a 12-hour infusion for 14 days. Temporary improvements were seen in granulocyte counts, monocyte counts, and reticulocyte counts in six of eight patients with aplastic anemia and five of seven patients with myelodysplastic syndromes. The patients with myelodysplastic syndromes had larger increases in granulocyte, monocyte, and reticulocyte counts than did those with aplastic anemia, and they also had increases in the numbers of eosinophils (two of seven), immature myeloid cells (two of seven), and myeloblasts (two of seven) that were not observed in patients with aplastic anemia. There was no reduction in erythrocyte transfusion requirements, and no effect was observed on platelet counts. There was only minimal toxicity consisting of transient low- back discomfort, anorexia, myalgias/arthralgias, and low-grade fever. Our data suggest that GM-CSF is well tolerated and is more likely to result in elevations of blood counts in patients with myelodysplasia than in patients with aplastic anemia, but the role of GM-CSF therapy in these disorders remains to be determined.  相似文献   
533.
Leukemia of non-T lineage natural killer cells   总被引:2,自引:0,他引:2  
An unusual case of an aggressive leukemia of natural killer (NK) cells occurred in a 65-year-old male. Clinical characteristics of this case included hepatosplenomegaly, ascites, marrow infiltrate with leukemic cells, and a WBC up to 82.8 X 10(9) before therapy. One year before his presentation he had been noted to have a WBC of 12.1 X 10(9) with 78% lymphocytes, and 6 months before had noted intermittent fever and weight loss. He and his brother had well documented hereditary cold urticaria. The patient was treated with a modification of ProMACE CYTABOM regimen and had prompt regression of the leukemia with associated acute tumor lysis. Renal, hepatic, and marrow failure predominated during a terminal course that ended 22 days after therapy was commenced, and at autopsy there was no evidence for leukemic cell infiltrate in the liver, spleen or marrow. The leukemic cells were large granular lymphocytes by light and electron microscopic criteria, and had the following immunophenotype: CD2+, DR+, Leu7+, NKH1+, CD11+, CD3-, CD5-, CD4-, CD8-, CD16-. The cells displayed high antibody- dependent cell-mediated cytotoxicity (ADCC) and NK activity, and had a high rate of spontaneous proliferation in vitro that was not augmented by phytohemagglutinin (PHA), concanavalin A (Con A), or pokeweed mitogen (PWM). Southern analysis of DNA from leukemic cells revealed normal germline arrangements for the beta and gamma chains of the T cell antigen receptor and immunoglobulin heavy chain genes. The majority of metaphases were clonally abnormal revealing consistent rearrangements involving extra material attached to the long arms of chromosomes 5 and 11.  相似文献   
534.
Thalidomide as salvage therapy for chronic graft-versus-host disease   总被引:5,自引:2,他引:5  
Thalidomide has been reported to be an effective agent for treatment of chronic graft-versus-host disease (CGVHD). To determine the efficacy of this agent in patients with refractory CGVHD a total of 80 patients who failed to respond to prednisone (PSE) or PSE and cyclosporine (CSA) were treated with thalidomide. Sixteen patients (20%) had a sustained response, 9 with a complete remission and 7 with a partial response. Twenty-nine patients (36%) had thalidomide discontinued because of side effects, which included sedation, constipation, neuritis, skin rash, and neutropenia. Side effects were reversible with drug discontinuation except for mild residual neuritis in one case. Rashes and neutropenia have not previously been reported as thalidomide side effects when used for CGVHD treatment. We conclude thalidomide is immunosuppressive and active in the treatment of CGVHD. A high incidence of reversible side effects limited dose intensity and reduced the number of patients who could benefit from treatment.  相似文献   
535.
Nowadays, technology is increasingly used to increase people’s well-being. For example, many mobile and Web-based apps have been developed that can support people to become mentally fit or to manage their daily diet. However, analyses of current Web-based interventions show that many systems are only used by a specific group of users (eg, women, highly educated), and that even they often do not persist and drop out as the intervention unfolds. In this paper, we assess the impact of design features of Web-based interventions on reach and adherence and conclude that the power that design can have has not been used to its full potential. We propose looking at design research as a source of inspiration for new (to the field) design approaches. The paper goes on to specify and discuss three of these approaches: personalization, ambient information, and use of metaphors. Central to our viewpoint is the role of positive affect triggered by well-designed persuasive features to boost adherence and well-being. Finally, we discuss the future of persuasive eHealth interventions and suggest avenues for follow-up research.  相似文献   
536.
537.
微核实验评价自制烤瓷合金的生物相容性   总被引:1,自引:1,他引:1  
目的:通过微核实验检测自制Ni-Cr-Ti烤瓷合金对小鼠的致畸作用,评价其生物相容性. 方法:实验于2006-04/08在中国医科大学中心实验室完成.①实验分组:选择N1H纯系小鼠80只,按随机数字表法分为8组,每组10只:Ni-Cr-Ti合金组(剂量分别为0.02,0.002,0.000 2 mL/kg)、纯钛浸提液组(剂量分别为0.02,0.002,0.000 2 mL/kg),阴性对照组(生理盐水),阳性对照组(注射用环磷酰胺,75 mg/kg).②实验方法:按50 mL/kg口服同剂量的浸提液,各组均于一次给药后24 h,麻醉后处死小鼠,取小鼠骨髓细胞.③实验评估:光镜下计数1 000个嗜多染红细胞的微核细胞数,并计数嗜多染红细胞与正红细胞的比值,即P/N比值.比值≥1,属于正常,比值<1,则可能受试物对骨髓细胞产生毒性. 结果:Ni-Cr-Ti合金组、纯钛浸提液组每1 000个嗜多染红细胞的微核细胞数与阴性对照组比较,差异无显著性意义(P>0.05),即Ni-Cr-Ti合金、纯钛浸提液对骨髓细胞无毒性.阳性对照组每1 000个嗜多染红细胞的微核细胞数高于Ni-Cr-Ti合金组、纯钛浸提液组,差异有显著性意义(P<0.01),对骨髓有毒性作用.Ni-Cr-Ti合金组、纯钛浸提液组P/N比值均≥1. 结论:自制Ni-Cr-Ti合金对小鼠无致畸作用,有较良好的生物相容性.  相似文献   
538.
The authors describe a prototype elution method employing chloroquine, a quinoline derivative, to elute IgG antibodies from the platelet surface. This chloroquine elution technique is relatively easy to perform and is effective in the removal of alloantibodies from the platelet surface. Eluted alloantibody was immunologically active once the chloroquine was removed from the eluate. The major advantage of this technique is that serologic testing of platelets after elution is possible, as 50 percent of the platelets remain after exposure to hypertonic acid chloroquine solution. Antigens on the platelet surface maintained their antigenicity subsequent to treatment, although measurable reductions in PIA1 reactivity occur. The elution technique was also successful in removing IgG from the platelet surface in patients with diseases involving elevated levels of platelet-associated IgG.  相似文献   
539.
Published reports have confirmed the superior sensitivity of the manual hexadimethrine bromide (Polybrene) test (MPT) for demonstrating many alloantibodies in vitro; however, the clinical significance of alloantibodies demonstrable exclusively by MPT has not been shown conclusively. A patient with macroglobulinemia experienced chills, fever, hemoglobinemia, and hemoglobinuria following the transfusion of 1 unit of red cells (RBCs) shown to be compatible by the low-ionic-strength antiglobulin (LIS-AG) method. Serologic investigation was negative. Intravascular hemolysis occurred with a second "compatible" unit. Serologic studies were again negative by LIS-AG and ficin-AG methods, but revealed anti-Jka by MPT. Both donors were Jk(a+b-), and 51Cr studies of the second donor's RBCs revealed a t1/2 of less than 30 minutes, with marked intravascular hemolysis. A LIS-AG-compatible Jk(a-) unit was transfused uneventfully, but with no rise in hematocrit. MPT next revealed anti-C; subsequent 51Cr studies with the Jk(a-), Cc donor's RBCs showed a 51Cr t1/2 of 100 minutes with slight intravascular lysis. Four transfusions of Jk(a-), C- blood were uneventful, but 5 days later the patient's hemoglobin declined. The following day, anti-E was demonstrable exclusively by MPT. 51Cr-labeled Jk(a-), C-, E- RBCs had normal 24-hour survival. The patient's hemoglobin rose to 11 g per dl following transfusions of Jk(a-), C-, E- RBCs, and he was discharged. In vitro studies employing the patient's purified IgM paraprotein revealed no interference with alloantibody binding or detection.  相似文献   
540.
盐酸维拉帕米渗透泵片溶出度与人体生物利用度研究   总被引:3,自引:0,他引:3  
溶出度按Weibull's分布处理得Td=5.76 h,T50=3.9 h,零级溶出速度常数Kt=9.9450,平均体外溶解时间MDT=5.391 h。测定8名健康受试者,单剂量口服,得Cmax=76.2±16.7 ng/ml,Tamx=8.0 h,t1/2=9.75 h,MRT=19.41 h,MAT=5.34 h,与Knoll公司SR片相比,Frel=101.71%;与市售普通片相比,Frel=96.16%。多剂量口服,得Cmax=121.47±34.5 ng/ml,Tmax=7.14 h。按Loo-Riegelman方程处理表明体内外显著相关。理论值与实测值基本相符。  相似文献   
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