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胃肠道黏膜屏障与自身免疫性疾病   总被引:4,自引:0,他引:4  
肠黏膜具有免疫和屏障功能。一方面,消化道黏膜不断地与病毒、细菌等微生物接触,在机体内担负起第一线的局部防御任务。另一方面,该系统对于食源性抗原、肠内常驻细菌可以产生免疫耐受。此种识别机制是由一个特殊的肠黏膜免疫组织“肠相关淋巴样组织”(gut associated lymphoidtissue,GALT)承担的。  相似文献   
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目的 总结Wilson’s病患者亲体肝移植和全肝移植术后血清铜蓝蛋白及尿铜水平的恢复情况。方法 自 2 0 0 0年 9月至 2 0 0 3年 11月我院为 2 6例Wilson’s病患者施行了肝移植术 ,均并发终末期肝硬变 ,其中 3例发生急性肝功能衰竭。术前血清铜蓝蛋白和尿铜水平分别为 (12 4 .8± 2 2 .8)mg/L和 (15 2 4 .8± 32 8.6 ) μg/ 2 4h ,其中行活体部分肝移植 2 2例 ,全肝移植 4例 ,亲体肝移植供体术前血清铜蓝蛋白水平为 (2 30 .4± 2 9.6 )mg/L ,尿铜水平均 <5 0μg/ 2 4h。结果 所有患者手术顺利 ,全肝移植患者术后 1、3、6及 12个月血清铜蓝蛋白和尿铜水平分别为 (32 0 .2±36 .8)mg/L、(380 .4± 4 5 .6 )mg/L、(36 0 .5± 37.6 )mg/L、(35 6 .2± 2 7.6 )mg/L和 (2 4 0 .4± 2 2 .8) μg/ 2 4h、(86 .5± 10 .6 ) μg/ 2 4h、(5 4 .2± 6 .8) μg/ 2 4h及 (46 .8± 3.4 ) μg/ 2 4h ;亲体肝移植患者术后 1、3、6及 12个月血清铜蓝蛋白和尿铜水平分别为 (2 16 .8± 2 0 .4 )mg/L、(2 4 8.5± 32 .6 )mg/L、(2 85 .4± 4 4 .3)mg/L、(2 6 0 .2± 36 .6 )mg/L和(380 .8± 37.6 ) μg/ 2 4h、(15 0 .6± 2 4 .5 ) μg/ 2 4h、(75 .5± 9.6 ) μg/ 2 4h及 (6 0 .3± 5 .8) μg/ 2 4h。结论 全肝移植和亲体肝  相似文献   
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目的观察α-干扰素(IFN-α)治疗肝癌产生耐药性的过程,探讨其机制。方法裸鼠肝内原位接种裸鼠人肝癌高转移裸鼠模型LCI-D20肿瘤组织,随机分为7组,每组6只。其中治疗组于接种肿瘤后第2天皮下注射给予IFN-α(1.5×10~7 U/kg体重/d)20 d,治疗组A和B裸鼠于停药后第1和21天分别被处死;治疗组C和D于停药后第21天再次给予同剂量IFN-α(1.5×10~7 U/kg体重/d)联合格列卫(100mg/kg体重/d,灌胃)治疗20 d。对照组E~G分别在接种肿瘤后第28、48、68天被处死。观察裸鼠体重,肿瘤大小、体积,检测血清血管内皮细胞生长因子(VEGF)浓度、肿瘤组织微血管密度。抽提A、D、E、G各组总RNA做关于血管生成SuperArray基因芯片。结果A~G组肿瘤的大小分别为0.27、1.54、3.22、2.23、0.68、1.93、3.98 g,其中组A和组E,组D和组G相比,肿瘤大小差异有统计学意义(P<0.05)。外周血VEGF浓度组A和组E,组C、D和组G相比差异有统计学意义(P<0.05)。芯片结果提示在IFN-α治疗过程中,肝癌组织VEGF mRNA和裸鼠血清中的VEGF仍保持较低水平,而PDGF-AA mRNA的表达水平逐渐升高。组A微血管密度显著低于组E,而在组C和组G间差异无统计学意义。HE染色显示治疗组与对照组相比,异常核分裂象增多,肿瘤周围包膜变薄,纤维成分减少。结论肝癌可对IFN-α治疗产生耐药性,可能的机制为肝癌肿瘤血管生成由VEGF依赖转化为PDGF依赖。  相似文献   
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2008年9月底制定了肝细胞肝癌外科治疗方法的选择,全文如下.  相似文献   
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Six-year survival of cirrhosis was assessed in a series of 1155 consecutive patients (751 men, 404 women). Among the men, 33% were alcoholics and 18% were HBsAg positive; corresponding figures for the women were 15% and 6%, respectively. Features of decompensation at first presentation were observed in 63% of the patients. Six-year survival was 54% in compensated and 21% in decompensated patients. No significant differences in survival were found between alcoholics and nonalcoholics. Leading causes of death were liver failure (49%), hepatocellular carcinoma (22%), and bleeding (13%). The prognostic role of 21 variables was evaluated separately in compensated and decompensated patients by the Cox's regression model. The following variables were found to be significant predictors of death risk in compensated patients: male sex, HBsAg positivity, age, prothrombin time prolongation, and esophageal varices. In decompensated disease the significant indicators of death risk were: hepatocellular carcinoma, encephalopathy, hemorrhage, SGOT, esophageal varices, gamma globulins, prothrombin time prolongation, continued abuse of alcohol, HBsAg positivity, gamma glutamyl transpeptidase, and cholinesterase. A simple prognostic index based upon the relative risk coefficient of the significant variables is suggested.Members of the Liver Study Group are: Maria Caltagirone, Gabriella Filippazzo, Giovanni Gatto, Gandolfo Giannuoli, Silvio Margin, Guiseppe Malizia, Lorenzo Maniaci, Maria Pia Marcenó, Alberto Maringhini, Rocco Micciolo, Salvatore Orsini, Fabio Pace, Ugo Palazzo, Linda Pasta, Giuseppina Russo, Rosa Giovanna Simonetti, Mario Spinello, Mario Traina, Mario Valenza, Maria Vinci, Giovanni Vizzini.  相似文献   
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High-risk combinations of recipient and graft characteristics are poorly defined for liver retransplantation (reLT) in the current era. We aimed to develop a risk model for survival after reLT using data from the European Liver Transplantation Registry, followed by internal and external validation. From 2006 to 2016, 85 067 liver transplants were recorded, including 5581 reLTs (6.6%). The final model included seven predictors of graft survival: recipient age, model for end-stage liver disease score, indication for reLT, recipient hospitalization, time between primary liver transplantation and reLT, donor age, and cold ischemia time. By assigning points to each variable in proportion to their hazard ratio, a simplified risk score was created ranging 0–10. Low-risk (0–3), medium-risk (4–5), and high-risk (6–10) groups were identified with significantly different 5-year survival rates ranging 56.9% (95% CI 52.8–60.7%), 46.3% (95% CI 41.1–51.4%), and 32.1% (95% CI 23.5–41.0%), respectively (< 0.001). External validation showed that the expected survival rates were closely aligned with the observed mortality probabilities. The Retransplantation Risk Score identifies high-risk combinations of recipient- and graft-related factors prognostic for long-term graft survival after reLT. This tool may serve as a guidance for clinical decision-making on liver acceptance for reLT.  相似文献   
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Aránzazu Caballero-Marcos  Magdalena Salcedo  Roberto Alonso-Fernández  Manuel Rodríguez-Perálvarez  María Olmedo  Javier Graus Morales  Valentín Cuervas-Mons  Alba Cachero  Carmelo Loinaz-Segurola  Mercedes Iñarrairaegui  Lluís Castells  Sonia Pascual  Carmen Vinaixa-Aunés  Rocío González-Grande  Alejandra Otero  Santiago Tomé  Javier Tejedor-Tejada  José María Álamo-Martínez  Luisa González-Diéguez  Flor Nogueras-Lopez  Gerardo Blanco-Fernández  Gema Muñoz-Bartolo  Francisco Javier Bustamante  Emilio Fábrega  Mario Romero-Cristóbal  Rosa Martin-Mateos  Julia Del Rio-Izquierdo  Ana Arias-Milla  Laura Calatayud  Alberto A. Marcacuzco-Quinto  Víctor Fernández-Alonso  Concepción Gómez-Gavara  Jordi Colmenero  Patricia Muñoz  José A. Pons  the Spanish Society of Liver Transplantation 《American journal of transplantation》2021,21(8):2876-2884
The protective capacity and duration of humoral immunity after SARS-CoV-2 infection are not yet understood in solid organ transplant recipients. A prospective multicenter study was performed to evaluate the persistence of anti-nucleocapsid IgG antibodies in liver transplant recipients 6 months after coronavirus disease 2019 (COVID-19) resolution. A total of 71 liver transplant recipients were matched with 71 immunocompetent controls by a propensity score including variables with a well-known prognostic impact in COVID-19. Paired case–control serological data were also available in 62 liver transplant patients and 62 controls at month 3 after COVID-19. Liver transplant recipients showed a lower incidence of anti-nucleocapsid IgG antibodies at 3 months (77.4% vs. 100%, < .001) and at 6 months (63.4% vs. 90.1%, < .001). Lower levels of antibodies were also observed in liver transplant patients at 3 (= .001) and 6 months (< .001) after COVID-19. In transplant patients, female gender (OR = 13.49, 95% CI: 2.17–83.8), a longer interval since transplantation (OR = 1.19, 95% CI: 1.03–1.36), and therapy with renin–angiotensin–aldosterone system inhibitors (OR = 7.11, 95% CI: 1.47–34.50) were independently associated with persistence of antibodies beyond 6 months after COVID-19. Therefore, as compared with immunocompetent patients, liver transplant recipients show a lower prevalence of anti-SARS-CoV-2 antibodies and more pronounced antibody levels decline.  相似文献   
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Nucleos(t)ide analogs (NAs) cannot completely suppress the risk of hepatocellular carcinoma (HCC) in patients with chronic hepatitis B (CHB). This study aimed to identify the risk factors for HCC development in naïve CHB patients treated with current NA. Patients receiving NA (n = 905) were recruited retrospectively from the 17 hospitals of the Japanese Red Cross Liver Study Group. All treatment-naïve patients had been receiving current NA continuously for more than 1 year until the end of the follow-up. We analyzed the accuracy of predictive risk score using the area under receiver operating characteristic curve. The albumin–bilirubin (ALBI) score was significantly improved by NA therapy (−0.171 ± 0.396; p < 0.001 at Week 48). A total of 72 (8.0%) patients developed HCC over a median follow-up of 6.2 (1.03–15.7) years. An independent predictive factor of HCC development was older age, cirrhosis, lower platelet counts at baseline and ALBI score, and alpha-fetoprotein (AFP) at 1 year after NA therapy according to multivariate analysis. The accuracy was assessed using the PAGE-B, mPAGE-B, aMAP, APA-B, and REAL-B scores that included these factors. Discrimination was generally acceptable for these models. aMAP and REAL-B demonstrated high discrimination with 0.866/0.862 and 0.833/0.859 for 3- and 5-year prediction from the status of 1 year after NA therapy, respectively. Baseline age and platelet count, as well as ALBI and AFP one year after NA, were useful for stratifying carcinogenesis risk. The aMAP and REAL-B scores were validated with high accuracy in Japanese CHB patients.  相似文献   
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