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191.
Langerhans cell sarcoma in a patient who underwent transplantation   总被引:1,自引:0,他引:1  
Langerhans cell sarcoma is a rare, aggressive tumour that may metastasize to many organs, likely leading to death of the patient within 1 year. We present the first case described in the literature in a patient who underwent transplantation.  相似文献   
192.
Previously, we reported that allogeneic skin grafts were rapidly rejected by CD28 and CD40 ligand double deficient mice mediated by CD8+ T cells. These results indicated that some elements in addition to CD28- and CD40-mediated costimulation provide stimulatory signals for the activation of donor-specific CD8+ T cells. In this report, we investigated the role of inflammation associated with transplantation on costimulation-independent priming of CD8+ T cell during graft rejection. B6 RAG1 KO mice were transplanted with BALB/c-skin and adoptively transferred with syngeneic CD8+ T cells the same day or 50 days after transplantation. When blockade of CD28- and CD40-mediated costimulation failed to prevent acute rejection of freshly transplanted skin grafts, it efficiently delayed rejection of well-healed skin grafts. These results showed that factors associated with transplantation have essential roles in inducing costimulation blockade-resistant allograft rejection. Costimulation blockade failed to prevent acute graft-infiltration of NK cells and increasing expression of intragraft IL-12 and IL-15. These factors may trigger the graft-infiltration and priming of CD8+ T cells to induce costimulation blockade-resistant allograft rejection.  相似文献   
193.
We evaluated twenty renal transplant subjects at various stages of BKV nephritis (BKVN) for BKV-specific IgG and IgM antibodies using ELISA technique and BKV-DNA using PCR. They were divided as early onset (n = 7), stabilizing (n = 3), resolved (n = 8) and late onset (n = 2) BKVN. BKV-specific antibodies and BKV-DNA were simultaneously determined. The mean BKV-specific IgG level in early onset and stabilizing BKVN were 64 and 39 EIA units, and were significantly lower than 138 EIA units seen in resolved BKVN, P = 0.007, P = 0.008. The mean BKV-specific IgM levels in stabilizing BKVN was higher than resolved BKVN (130 vs 51 EIA units), P = 0.006. Mean plasma BKV loads for each group were 955,925, 5642 and 42 copies/mL of plasma, respectively. Prospective study in six BKVN cases revealed mean IgG, IgM levels and BKV-DNA at the time of diagnosis of BKVN as 39, 110 EIA units and 586,758 copies/mL of plasma, respectively. After a mean period of 5.2 months, IgG level increased to 120 EIA units (p = 0.0058) and had no detectable viral copies in circulation. Recovery from BKVN and elimination of BKV is associated with the development of BKV-specific IgG antibodies and this provides insight into the role of humoral immunity to BKV in the pathogenesis of BKVN.  相似文献   
194.
Despite recent improvement, significant racial disparities in outcome still persist after renal transplantation among African American patients in the United States. This study evaluated the association of race and ethnicity with allograft outcomes in a French population of 952 Caucasian (Cauc) patients and 140 African European (AE) patients who underwent renal transplantation in our center between 1987 and 2003. Demographic characteristics were similar for the two cohorts other than cause of end-stage renal failure (more hypertension among AE and more polycystic kidney disease among Cauc) and cold ischemia time (significantly longer for AE). Immunosuppressive treatment was comparable between groups. There were no significant differences between AE and Cauc in the incidence of acute rejection (31% vs. 30%). At 5 years post-transplant, patient survival (93% vs. 92%), graft survival (83% in both groups) and graft function (creatinine clearance 48 mL/min vs. 45 mL/min) were also similar among the AE and Cauc patients. We demonstrate that ethnic origin does not affect outcome after renal transplantation in France. Therefore, differences observed in the United States cannot be only related to immunologic or pharmacologic factors. The results of renal transplantation in patients of African origin could be improved with universal immunosuppressive drug coverage.  相似文献   
195.
Proteinuria 1 year after transplantation is associated with poor renal outcome. It is unclear whether low-grade (<1 g/24 h) proteinuria earlier after transplantation and its short-term change affect long-term graft survival. The effects of proteinuria and its change on long-term graft survival were retrospectively assessed in 484 renal transplant recipients. One- and 3-month proteinuria correlated with donor age, donor cardiovascular death, prolonged cold and warm ischemia times and acute rejection. One- and 3-month proteinuria (per 0.1 g/24 h, hazard ratio (HR): 1.07 and 1.15, p<0.0001)-especially low-grade proteinuria (HR: 1.20 and 1.26, p<0.0001)-were powerful, independent predictors of graft loss. Its short-term reduction correlated with arterial pressure (AP) (the lower the 3-month diastolic and 12-month systolic AP, the lower the risk of increasing proteinuria during 1-3 months and 3-12 months periods, respectively: Odds ratio (OR) per 10 MmHg: 0.78, p=0.01 and 0.85, respectively, p=0.02), and was associated with decreased long-term graft loss (per 0.1 g/24 h: HR: 0.88 and 0.98, respectively, p<0.0001), independently of initial proteinuria. Early low-grade proteinuria due to pre-transplant renal lesions, ischemia-reperfusion and immunologic injuries is a potent predictor of graft loss. Short-term reduction in proteinuria is associated with improved long-term graft survival.  相似文献   
196.
CD154-specific antibody therapy prevents allograft rejection in many experimental transplant models. However, initial clinical transplant trials with anti-CD154 have been disappointing suggesting the need for as of yet undetermined adjuvant therapy. In rodents, donor antigen (e.g., a donor blood transfusion), or mTOR inhibition (e.g., sirolimus), enhances anti-CD154's efficacy. We performed renal transplants in major histocompatibility complex-(MHC) mismatched rhesus monkeys and treated recipients with combinations of the CD154-specific antibody IDEC-131, and/or sirolimus, and/or a pre-transplant donor-specific transfusion (DST). Therapy was withdrawn after 3 months. Triple therapy prevented rejection during therapy in all animals and led to operational tolerance in three of five animals including donor-specific skin graft acceptance in the two animals tested. IDEC-131, sirolimus and DST are highly effective in preventing renal allograft rejection in primates. This apparently clinically applicable regimen is promising for human renal transplant trials.  相似文献   
197.
腹股沟浅淋巴结移植的应用解剖   总被引:1,自引:0,他引:1  
本文在32侧成人尸体上,对腹股沟浅淋巴结的形态及血供进行了观察和测量。腹股沟部上外区淋巴结有恒定的旋髂浅血管供应。动脉外径平均约1.5mm,干长21.8mm,营养2~6个淋巴结、该区是吻合血管移植淋巴结的首选供区。  相似文献   
198.
MRI在心脏瓣膜病中的诊断价值   总被引:1,自引:0,他引:1  
目的 探讨多序列MR扫描在心脏瓣膜病中的诊断价值。方法 回顾性分析56例心脏瓣膜病患者的影像学资料,患者分别采用超声心动图(UCG)、二维(2D)黑血及亮血序列、K-空间节段真实稳态进动快速扫描序列(True FISP)对瓣膜病进行定性评价,15例患者还进行小角度快速激发(FLASH)电影序列和流速编码电影(VEC)定量分析,并将MR结果与UCG进行对比。结果 UCG和MRI诊断二尖瓣狭窄(MS)2例,二尖瓣关闭不全(MI)23例;主动脉瓣狭窄(AS)7例,其中二瓣畸形5例;主动脉瓣关闭不全(AI)13例;三尖瓣关闭不全(TI)2例;复合或联合瓣膜病9例。受累心腔的增大和升主动脉的扩张是其主要形态学改变,异常的血液湍流信号是受累瓣膜的直接征象。VEC-MR定量分析与多普勒超声一致性好:6例AS,MR和UCG检查结果相关性分析,相关系数和校正相关系数分别为:R=0,975、Rsq=0.951(P〈0.01),AI9例,分别为R=0.965、Rsq=0.932(P〈0.01)。结论 MR多序列综合扫描可对心脏瓣膜病特别是主动脉瓣疾病进行准确的定性及定量评价。  相似文献   
199.
选择髂内或髂外动脉吻合对移植肾的影响   总被引:3,自引:0,他引:3  
目的 探讨肾移植动脉重建选择髂外或髂内动脉时移植肾血流参数、肾脏功能和血管并发症的差异。方法 135例初次肾移植患者随机分为2组,2组患者平均年龄、HLA错配数目、淋巴细胞毒试验、冷/热缺血时间差异均无统计学意义(P〉0.05),术后免疫抑制剂应用方案相同。应用髂外动脉端侧吻合66例,髂内动脉端端吻合69例。随访3个月,比较2组患者肾脏功能、彩色多普勒肾脏血流参数和血管并发症发生率。结果 髂内动脉、髂外动脉组2组患者术后3个月时肾功能监测指标(Cr:118.41 vs123.68μmol/L),移植肾主肾动脉、段动脉、大叶间动脉血流及阻力指数差异无统计学意义(P〉0.05)。结论 肾移植动脉重建选择髂内外动脉对移植肾功能及血液流变学无明显影响,动脉选择应根据患者具体情况决定。  相似文献   
200.
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