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71.
Chronic rejection accounted for 32% of all graft losses in 7123 pediatric transplants. In a previous study acute, multiple acute and late acute rejections were risk factors for the development of chronic rejection. We postulated that the recent decrease in acute rejections would translate into a lower risk for chronic rejection among patients with recent transplants. We reviewed our data on patients transplanted from 1995 to 2000, and using multivariate analysis and a proportional hazards model developed risk factors for patients whose grafts had failed due to chronic rejection. A late initial rejection increased the risk of chronic rejection graft failure 3.6-fold (p < 0.001), while a second rejection resulted in further increase of 4.2-fold (p < 0.001). Recipients who received less than 5 mg/kg of cyclosporine at 30 days post-transplant had a relative risk (RR) of 1.9 (p = 0.02). Patients transplanted from 1995 to 2000 had a significantly lower risk (RR = 0.54, p < 0.001) of graft failure from chronic rejection than those who received their transplants earlier (1987-94). Since we were able to demonstrate that there is a decreased risk of chronic rejection graft failure in our study cohort, we would conclude that the goal of future transplants should be to minimize acute rejections.  相似文献   
72.
  l Gü  rsel  Haluk Tü  rktas  Nahide G  k  ora  Ishak   zel Tekin 《The Journal of asthma》1997,34(4):313-319
The aim of the present study was to investigate whether sputum eosinophil cationic protein (ECP) concentrations could be a useful marker in the differential diagnosis between intrinsic asthma and chronic obstructive pulmonary disease (COPD). For this purpose total blood eosinophil counts were obtained and concentrations of serum and sputum ECP from 10 nonatopic asthmatics with a mild attack and 9 COPD patients with acute exacerbation were measured by radioimmunoassay. Mean serum ECP concentration was 54.3 ± 23.0 g/L in the asthmatic group and 83.3 ± 79.2 g/L in the COPD group (p: n.s.). In the group of asthmatics mean sputum ECP level was 984.5 ± 1245.5 mg/L/g sputum and in the COPD group it was 417.5 ± 363.5 mg/L/g sputum. There was no significant difference in sputum ECP levels between patients with asthma and COPD. We conclude that neither sputum nor serum ECP levels are useful markers in differential diagnosis of asthma attack and acute exacerbation of COPD.  相似文献   
73.
Abstract  We previously demonstrated that cytomegalovirus (CMV) infection enhanced perivascular inflammation in rat aortic allografts. In this study, we investigated the relationship between the CMV infection load and the magnitude of perivasculitis (chronic rejection) in aortic transplants. Rats received or-thotopic abdominal aortic grafts, different degrees of total body irradiation (TBI) for immunosuppres-sion and CMV inoculation. The spleens of the rats receiving 5 Gy of TBI contained more infectious virus and viral antigens than those of rats receiving 3 Gy of TBI or no TBI. Although the number of inflammatory cells infiltrating the perivascular area was decreased after TBI, CMV infection resulted in increased perivasculitis in rats that received 5 Gy of TBI as compared to non-infected animals. This virus-induced effect was characterized predominantly by an increased T-cell infiltration, including CD4 and CD8 T-cells. It is concluded that an enhanced systemic CMV infection during severe immunosuppressive therapy can accelerate the development of chronic rejection, which seems to be mediated mainly by T-cells.  相似文献   
74.
目的:探讨胃癌微卫星不稳定性(MSI)与胃腺癌中皿管内皮生长因子(VEGF)之间的关系。方法:应用PCR—SSCP技术检测30例胃腺癌5个位点的微卫星不稳定性,同时应用免疫组织化学的方法检测肿瘤皿管内皮生长因子(VEGF)蛋白的表达。结果:MSI阳性率为43.4%(13/30)。VEGF阳性率为60%(18/30)。MSI—H胃癌VEGF的表达显著减少。结论:MSI—H的胃癌与MSS胃癌可能存在两种不同的胃癌及肿瘤血管新生形成的途径。MSI—H肿瘤较低的VEGF表达可能可以解释为何MSI-H胃癌有较低的侵袭性。  相似文献   
75.
神经根慢性嵌压损伤的动物模型建立   总被引:3,自引:0,他引:3  
目的:建立一种由自身骨性增生造成神经根慢性嵌压损伤的动物模型,为相关实验提供造模方法一方法:30只健康家猫,手术显露右侧C7、C8和L5、L6冲经根及其椎问孔内口,用牙髓钻破坏椎间孔周围骨皮质后,将“V”形松质骨块沿骨壁嵌于神经根通道的骨性管道内及侧隐窝后方,左侧做正常对照。在造模术前和术后第2、4、8、12、24周行磁刺激运动诱发电位(MEP)检测,每次随机选6只,4~5只行影像学检查,以确定神经根通道的狭窄程度和神经根受压状态,6只均做病理组织学检查和椎间孔截面积测量。结果:术后早期实验侧肢体出现行为异常:而后有不同程度肌萎缩;后期部分肢体远端出现溃疡。影像学检查随着嵌压时间延长.实验侧椎间孔骨痂增多,狭窄加重。神经根受压变形,椎间孔骨性截面积8周后明显减小,与对照侧比较有显著性差异。术后2周,神经根组织学检查主要表现为神经束膜、内膜的水肿。髓鞘肿胀;4周后发生节段性脱髓鞘:8周时神经轴突增粗、断裂,远端瓦勒氏变性;12周后变性冲经结构崩解、吸收,形成空洞:24周时整个神经干纤维化。术后4周时实验侧MEP开始出现潜伏期延长;8周时伴有波形分化不清;12周波幅明显下降:24周MEP的引出困难,部分电位消失。结论:采用椎问孔内自体松质骨植入,造成神经根慢性嵌压性损伤模型成功率高,操作简单,适用于脊柱各个节段,其损伤部位和形式与临床更为接近。  相似文献   
76.
慢性乙肝患者血清细胞因子、乙肝病毒与肝纤维化的关系   总被引:1,自引:0,他引:1  
目的:探讨慢性乙肝患血清细胞因子(TGF-β,TNF-α,IL-6,IL-8),乙肝病毒(HBV)对肝纤维化(HA,PCⅢ,C-Ⅳ,LN)的影响作用。方法:采用ELISA和RIA方法检测171例慢性乙肝患血清TGF-β,TNF-α,IL-6,IL-8,HLA,PCǚ,C-Ⅳ,LN的水平,HBV-DNA定量检测采用PCR方法。结果:慢性乙肝患血清TGF-β,TNF-α,IL-6,IL-8,HA,PCⅢ,C-Ⅳ,LN的含量均不同程度高于对照组,且随肝损害程度的加重而升高,与肝损害程度呈正相关关系(P<0.05或P<0.01);须血清TGF-β1水平与血清HA,PCⅢ,C-Ⅳ,LN水平具有直线相关关系。HBV-DNA阳性组(Ⅱ组)均高于HBV-DNA阴性组(I组),且在慢性中,重度肝炎间差异显(P<0.05)。结论:血清TGF-β,TNF-α,IL-6,IL-8参与慢性乙肝的发病机制及肝纤维化的形成,且与病毒复制的活跃程度相关。  相似文献   
77.
慢性肝病、原发性肝癌病人血清、肝组织纳米细菌的检测   总被引:4,自引:0,他引:4  
目的 研究慢性肝病和原发性肝癌病人血清、组织中纳米细菌(NB)感染,为其发生机制提供新的认识。方法 55例慢性肝病(25例慢性乙肝和30例肝炎后肝硬化)、43例肝癌病人和336例健康人血清采用ELISA、免疫组化和钙染色;53例慢性肝病(28例慢性乙肝和25例肝硬化)、43例肝癌和15例对照肝组织行免疫组化染色,部分阳性组织透射电镜观察。结果 (1)慢性肝病、肝癌病人和健康人血清ELISA检测阳性率分别为20.0%、9.3%和8.0%,慢性肝病NB感染率高于健康人(P〈0.05)。免疫组化染色感染率分别为14.5%、4.7%和5.7%(P〈0.05)。钙染色分别为7.3%、4.7%和6.5%(P〉0.05)。(2)慢性肝病、癌及癌旁、对照组免疫组化阳性率分别为:20.8%、16.3%、14.0%和0%(P〉0.05)。部分肝癌和癌旁组织透射电镜观察发现纳米细菌样微生物结构(3/5)。结论 部分慢性肝病、肝癌病人血清、组织中存在纳米细菌感染,慢性肝病血清中纳米细菌感染率高于健康人。  相似文献   
78.
Arthroscopic shoulder surgery has become a safe tool for evaluation and treatment of a wide range of shoulder problems with few complications. With ever-improving technology (and commitment to motor skill development among arthroscopists), we can expect to maintain this low rate despite increasing procedure complexity. Avoiding complications in arthroscopic shoulder surgery requires careful preoperative planning, judicious patient selection, a thorough understanding of arthroscopic anatomy, and facility with arthroscopic techniques.  相似文献   
79.
Neurotrophic effects of the growth hormone (GH), insulin-like growth factor-1 (IGF-1) and insulin on the central nervous system have become more apparent in the past decade. In this study, we measured serum and cerebrospinal fluid (CSF) concentrations of GH, IGF-1 and insulin in 35 patients with motor neuron disease (MND) [24 patients with definite amyotrophic lateral sclerosis (ALS) and 11 patients with progressive bulbar palsy] and in 40 healthy controls. Levels of serum concentrations of GH and IGF-1 did not significantly differ between the MND patient group and the healthy controls, while the level of insulin was significantly decreased ( P  = 0.0033) in the MND patient group. However, levels of all three examined parameters in CSF were significantly lower in the MND group than in the healthy controls with the statistical significance for IGF-1 and insulin of P  < 0.001. This finding has not been reported previously, and further investigations into its association with ALS should establish whether it can be used as an early marker of the disease, or whether it merely represents a consequence of ALS development.  相似文献   
80.
目的探讨舒利迭(吸入型肾上腺皮质激素与长效β2-受体激动剂的预混制剂)联合双水平气道正压通气(B iPAP)对稳定期慢性阻塞性肺疾病(COPD)的治疗作用。方法稳定期COPD病人52例,舒利迭TM50/250,1吸/次,2次/d;B iPAP,吸气压力(IPAP)10~20cm H2O,呼气压力(EPAP,也称PEEP)3~6cm H2O,吸氧浓度(FiO2)3L/m in,每天夜间通气6~8h。观察治疗前、治疗后12周病人临床症状、生活质量、健康状态和肺功能。结果治疗前、治疗后12周病人的临床症状、急性加重次数及严重程度、健康状态和生活质量、肺功能等指标比较差异有统计学意义(P<0.05)。结论舒利迭联合B iPAP治疗稳定期COPD病人能够明显改善其症状,提高生活质量,有一定的临床应用价值,对减缓COPD病人肺功能下降有积极意义。  相似文献   
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