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目的:探讨乳腺癌组织中核呼吸因子-1(NRF-1)蛋白表达与乳腺癌发生、发展及临床病理特征的关系。方法:采用免疫组化EnVision二步法,对211例乳腺癌组织和50例乳腺良性病变组织中NRF-1蛋白表达进行检测。结果:NRF-1蛋白表达定位于细胞核,着色呈棕黄色,乳腺癌中阳性表达(82.7%)低于乳腺良性病变组织阳性表达(100%),χ2=100.288,P=0.000;高分化乳腺癌NRF-1阳性率明显高于中、低分化乳腺癌(χ2=16.242,P=0.001;χ2=72.802,P=0.000),中分化乳腺癌也明显高于低分化乳腺癌,χ2=30.190,P=0.000。乳腺癌淋巴结转移患者NRF-1蛋白阳性表达率明显低于未转移者,χ2=12.025,P=0.007;TNM分期中I期NRF-1蛋白阳性表达率明显高于Ⅱ、Ⅲ期,χ2=12.025,P=0.007。结论:NRF-1蛋白的表达可能与乳腺癌的发生发展密切相关,可作为乳腺癌患者疾病进展监控和预后观测的指标,具有临床应用价值。  相似文献   
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Background The introduction of platelet (PLT) additive solutions (PASs) and pathogen reduction (PR) technologies possibly allow extension of PLT shelf life. It was our aim to compare in vitro quality of leucocyte‐reduced PLT concentrates (PCs) stored in various PASs, including PR, with those in plasma during 8 days of storage. The study was performed in four blood centres where each tested four conditions. Study Design and Methods In paired experiments (n = 12), buffy coat pools were made to which various storage media were added. Plasma served as reference; two centres used InterSol followed by PR (InterSol+PR) and InterSol without PR; T‐sol, SSP+ and Composol were also studied. Results All PCs fulfilled release criteria (pH37°C > 6·6; swirl present) until Day 8. Marked differences were seen for other parameters, including CD62P expression: 28 ± 5; 31 ± 7; and 39 ± 9% for T‐sol, Intersol+PR and without PR, respectively, which were higher as found for Composol (12 ± 3%), SSP+ (15 ± 5%) and plasma (15 ± 6%). Three parameters (CD62P, Annexin A5, and lactate concentration) were collapsed into one rating value (6 = good quality, 0 = poor quality); PLTs in plasma had a rating of 2·8 ± 1·0, which was higher as for T‐Sol (1·5 ± 0·5), InterSol+PR (1·3 ± 0·6) and without PR (1·7 ± 0·5). PLTs in potassium‐ and magnesium‐containing PASs showed higher ratings as plasma, 4·3 ± 0·5 for Composol and 3·8 ± 0·8 for SSP+. Conclusion PLT concentrates in plasma, SSP+ and Composol scored better using an arbitrary rating system as PLTs stored in T‐Sol or InterSol; PR further impaired rating parameters. The applicability of these differences in rating for clinical effects needs a clinical study.  相似文献   
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Platelet functions such as aggregation and clot retraction are often abnormal in chronic mylogenous leukemia (CML) patients. However, the molecular mechanisms of these altered functions are unknown. As expression of the p210bcr-abl oncogene product, a constitutively active tyrosine kinase, is known to have an essential role in the pathogenesis of CML and tyrosine phosphorylation is intimately involved in various aspects of platelet activation, we examined the pattern of protein tyrosine phosphorylation in platelets from 15 CML patients by immunoblotting with a monoclonal antiphosphotyrosine antibody (4G10). Before and after stimulation with thrombin, the only consistent difference between normal and CML platelets was the presence of a tyrosine phosphorylated protein with a relative molecular weight of 39 kD. This tyrosine phosphorylated protein was identified as crid, an SH2, SH3 containing adapter protein. Thus, as previously demonstrated for neutrophils from CML patients, tyrosine phosphorylation of p39crkl persists in mature platelets. No tyrosine phosphorylation of crid was detected following stimulation with thrombin in normal platelets. However, crkl became incorporated into the Triton X-100 insoluble residue following thrombin stimulation in a manner dependent on platelet aggregation. Further, we found that crkl is an endogenous substrate for calpain, a protease that may be involved in postaggregation signaling processes. This suggests that crkl may be involved in the reorganization of the cytoskeleton during normal platelet aggregation and its tyrosine phosphorylation in CML platelets may contribute to the abnormal platelet function in CML patients. Finally, we found that thrombopoietin induces tyrosine phosphorylation of crk1 in normal platelets and FDCP cells genetically engineered to express human c-Mpl. This suggests that crk1 can be phosphorylated by a kinase other than p210bcr-abl and that crk1 may have a role in signaling by thrombopoietin.  相似文献   
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目的:严重的黏膜损伤是诱发造血干细胞移植后出现并发症的一常见原因,已有证据显示谷氨酰胺能降低接受化疗患儿黏膜炎的发生率。观察谷氨酰胺对异基因外周造血干细胞移植患者并发症及恢复的影响。方法:选择于2002-03/2006-11在河南省血液病研究所接受同胞异基因外周造血干细胞移植的48例血液系统肿瘤患者。所有患者及其家属对治疗和实验均知情同意,并经医院伦理委员会批准。所有患者移植前均处于完全缓解状态,营养中等或良好,心、肝、肾功能正常,将48例患者随机分为标准化全胃肠外营养液组(标准组,n=13)和加用谷氨酰胺的全胃肠外营养液组(谷氨酰胺组,n=35)。待患者中性粒细胞升至1.0×109L-1,且无任何感染指征,进行异基因外周造血干细胞移植。造血干细胞输注后第1天开始给予全胃肠外营养与胃肠外营养联合谷氨酰胺双肽,至中性粒细胞≥1.0×109L-1,且无消化道症状时停用。观察两组患者中性粒细胞恢复时间、出层流室时间以及关于感染、急性移植物抗宿主病等情况有无差异。结果:48例患者均进入结果分析。两组患者营养物质的摄入基本相同,谷氨酰胺组有6例发生黏膜炎,标准组有11例,差异显著(P<0.05);谷氨酰胺组有1例发生严重腹泻,标准组有5例,差异显著(P<0.05);谷氨酰胺组有3例发生临床感染,标准组有7例,差异显著(P<0.05);标准组中性粒细胞≥0.5×109L-1的持续时间短于谷氨酰胺组(P>0.05);谷氨酰胺组抗生素治疗时间及无菌病房居住时间较标准组短(P<0.05);两组急性移植物抗宿主病发生率差异无统计学意义(P>0.05)。结论:添加谷氨酰胺的全胃肠外营养可改善异基因造血干细胞移植患者的营养状态,减少感染及肠损害,减少急性移植物抗宿主病的发生,有利于异基因移植患者恢复。  相似文献   
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