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1.
目的 制备具有天然神经组织结构的支架,构建组织工程化面神经用于修复面神经损伤。方法 取家兔面神经,改良化学萃取法制备脱细胞神经基质,HE染色形态学观察去细胞及脱髓鞘情况,荧光分光光度计测定支架内细胞经Quant-iT PicoGreen工作液染色后的DNA含量。MTT法检测细胞在支架上的相对生长率从而检测支架的细胞毒性。结果 支架移植体呈圆柱形,弹性与正常神经基本一致,组织观察显示细胞结构未见残余完整细胞及细胞碎片残留,未见神经髓鞘及轴突结构,细胞外基质形成纵向排列结构,结构之间可见空隙。兔脱细胞面神经基质支架内残留的DNA含量较正常兔面神经明显下降(P<0.01)。神经基质供体无细胞毒性。结论 改良化学萃取法可有效去除面神经细胞,天然结构保存完好,细胞毒性低,可作为组织工程化面神经的支架。  相似文献   
2.
异体甘油保存皮与自体微粒皮复合移植的临床应用   总被引:1,自引:0,他引:1  
目的:寻找深度大面积\烧伤的早期治疗方法。方法:大面积深度烧伤于4-5天即行切痂,以异体甘油皮为支架,将有限的自体皮制作成微粒皮后均匀地复合植于创面。结果:对5例共12个肢体2个躯干进行早期切痂后异体甘油皮+自体微粒皮的复合移植,成活后的创面平堤,外观平整,颜色淡红或近拟正常皮肤,触饮,收缩少,结论:异体甘油保存皮+自体微粒皮复合移植是大面积深度烧伤较理想的治疗方法。  相似文献   
3.
We describe the clinical courses of 3 patients with hematologic malignancies (2 with acute myelogenous leukemia and 1 with multiple myeloma) who developed invasive fungal infections due to uncommon molds (Alternaria spp., Paecilomyces lilacinus, and Zygomycetes). Breakthrough invasive fungal infections of the sinus (n=1), lung (n=3), and pericardium (n=1) developed despite fluconazole prophylaxis and failed to respond to treatment with other licensed antifungal therapies, including amphotericin B (n=3), caspofungin (n=2), and voriconazole (n=3), and surgical intervention (n=2). Salvage therapy with posaconazole oral suspension resulted in successful outcomes in all 3 patients, who subsequently underwent allogeneic hematopoietic stem cell transplantation (HSCT) while on continued posaconazole therapy. The median duration of posaconazole treatment before HSCT was 5 months (range: 1.5-6 months). Posaconazole salvage therapy allowed successful allogeneic HSCT in 3 patients with refractory invasive mold infections.  相似文献   
4.
Abstract: The results of an intensive treatment program for patients 16–60 yr of age with de novo acute myeloid leukemia are presented. The patients were given conventional induction treatment with daunorubicin and cytarabine. Patients not entering complete remission (CR) after 1 course of daunorubicin/cytarabine were given 1 course of amsacrine/etoposide/cytarabine. Those entering complete remission received 3 consolidation courses using mitoxantrone, etoposide, amsacrine and cytarabine. One hundred and eighteen patients were enrolled. Complete remission was attained after 1–2 courses in 90 patients (76%). Another 6 patients reached CR after 3–4 induction courses for a total CR rate of 81%. If feasible, patients were offered either allogeneic or unpurged autologous bone marrow transplantation. Twenty-four patients underwent allogeneic bone marrow transplantation; 15 in first remission, 8 in second remission, 1 in early relapse. Thirty patients below 56 yr of age underwent autologous bone marrow transplantation in first remission. The overall probability of survival at 4 yr was 34%, and for patients below 40 yr of age 50%. Leukemia-free survival was 35% for the whole cohort of patients; 52% for patients below 40 yr of age. Patients undergoing allogeneic or autologous bone marrow transplantation in first remission had an overall survival of 86% and 47%, respectively, while the probability of leukemia-free survival in these groups was 87% vs. 40% at 4 yr. The CR rate and long-term results of this intensive treatment program compare favorably with other recent studies using intensive consolidation with allogeneic or autologous bone marrow transplantation or high dose cytarabine.  相似文献   
5.
BALB/c mice injected at birth with 10(8) semi-allogeneic (C57BL/6 x BALB.IgHb)F1 spleen cells develop a lupus-like syndrome in which autoantibodies bear exclusively the donor allotype. We have analyzed the evolution of donor B cell chimerism and the autoimmune manifestations during the first year of life in these mice. Anti-DNA, -histone, and -cardiolipin IgG antibodies as well as circulating immune complexes appeared in the second week of life, reached the highest values around the sixth week, and then progressively dropped to normal values after the sixth month in most mice. The kinetics of the evolution of the autoimmune manifestations, as well as the kinetics of serum donor Ig allotype, were parallel to the kinetics of donor B cell chimerism, which was particularly prominent in the spleens in early weeks of life, and progressively decreased after remission of the autoimmune syndrome. Membrane-proliferative glomerulonephritis, which was followed as the more representative histological abnormality in this model, was particularly evident after 10 weeks of life, but disappeared by the end of the follow-up. Interestingly, when mice with a self-limited disease were re-injected with 10(8) F1 spleen cells i.v., a flare in the serological manifestations was observed. In these re-injected mice a predominance of anti-DNA, IgG1 antibodies bearing exclusively the donor allotype was also observed, as in the early weeks of life.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
6.
Patrice Lumumba Peoples' Friendship University, Moscow. (Presented by Academician T. T. Berezov, Academy of medical Sciences.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 113, No. 4, pp. 355–358, April, 1992.  相似文献   
7.
8.
目的探讨治疗恶性血液病异基因造血干细胞移植(allo—HSCT)后肺部并发症与相关危险因素的关系。方法回顾性分析1991年8月至2004年6月157例allo—HSCT患者的临床资料。结果71例患者发生87例次肺部并发症,其中15例患者发生2次以上肺部并发症,总发生率为45.2%。直接死于肺部并发症者37例(23.6%),发生中位时间103d(1~886d)。其中细菌性肺炎32例,间质性肺炎8例,肺真菌病3例,肺水肿3例,肺结核2例,肺栓塞1例,2种或2种以上病原所致的肺部并发症38例次。单因素分析显示:患者年龄、疾病状态、供受者关系、HLA配型相合程度及广泛型慢性移植物抗宿主病(cGVHD)是影响移植后肺部并发症的危险因素。多因素分析显示:疾病状态和广泛型cGVHD与肺部并发症的发生显著相关(P<0.01)。结论肺部并发症是allo—HSCT后常见的并发症之一。患者移植时疾病状态和广泛型cGVHD是与allo—HSCT后肺部并发症发生相关的危险因素。  相似文献   
9.
目的:初步探讨在异基因造血干细胞移植(HSCT)中发生移植物抗宿主病(GVHD)患者DC40L表达的变化以及意义。方法:HSCT治疗重型β-地中海贫血(n=12)和遗传性溶血性贫血(n=1)成功植入的儿童患者,其中脐血移植(UCBT)8例,异基因外周血造血干细胞移植(allo-PBSCT)5例,在移植前、移植后发生GVHD时采用流式细胞仪检测和比较外周血中CD40L和CD40的表达。结果:3例UCBT无GVHD,其余均发生了Ⅰ-Ⅳ度急性GVHD。急性GVHD发生时CD4^ CD40L^ 和CD8^ CD40LT细胞表达明显升高,allo-PBSCT者更明显;慢性GVHD发生时患者的CD40L^ 、CD25^ 和CD69^ 在CD4^ 和CD8^ T细胞上的表达亦增加。CD19^ CD40^ B细胞的表达在UCBT和allo-PBSCT的3个月内则一直处于低于正常的水平。结论:CD40L高表达与GVHD的发生相关,提示CD40-CD40L共刺激途径在GVHD的发生中可能起着重要作用。  相似文献   
10.
Antigen stimulation of T cells results in a series of biochemical events including the interaction of both SH2 domains of ZAP-70 with phosphorylated ITAMS on the T cell receptor. In order to study the physiological relevance of decreasing native ZAP-70–SH2 interaction in vivo, we generated transgenic mice expressing a T cell-specific, dominant negative form of ZAP-70 consisting of only the tandem SH2 domains (ZAP-NC). Phenotypically, these animals had a comparable distribution of lymphocyte subsets in the thymus and spleen compared with the wild-type (WT) controls. However, examination of peripheral blood revealed a slow but progressive decrease in the number of lymphocytes, particularly CD4+ cells, with age (17% reduction by 3 months, 58% reduction by 6 months). Allogeneic responses were then evaluated in vitro as well as in vivo using a subcutaneous sponge matrix implant. Although spleen cells cultured for 4 days in vitro with alloantigen developed normal functional responses, allogeneic responses generated in vivo within a subcutaneous sponge matrix were impaired. This was characterized by a depression in cytotoxic T lymphocyte (CTL) activity, a 82% reduction in the frequency of helper T cells, and a 78% reduction in the capacity of sponge-infiltrating lymphocytes to produce IL-2 in response to secondary antigen stimulation. These results indicate that although overt lymphocyte development and in vitro function were unremarkable, expression of a truncated ZAP-70 affected the in vivo survival of peripheral lymphocytes and altered the in vivo generation of functional activity to alloantigen.  相似文献   
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