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1.
目的探讨血浆硫氧还蛋白还原酶(TR)在肺癌化疗疗效监测中的价值。方法将482例肺癌患者依据化疗疗效分为治疗未获益组(211例)和治疗获益组(271例),检测所有患者TR、癌胚抗原(CEA)、鳞状上皮细胞癌抗原(SCC-Ag)、细胞角蛋白19片段(CYFRA 21-1)、神经元特异性烯醇化酶(NSE)及胃泌素释放肽前体(ProGRP)水平。采用受试者工作特征(ROC)曲线评估各项指标单项及联合检测判断化疗疗效的价值。结果治疗未获益组TR、CEA及NSE水平均高于治疗获益组(P<0.05),2个组之间SCC-Ag、CYFRA21-1及ProGRP水平差异均无统计学意义(P>0.05)。治疗未获益组TR阳性率为56.40%,显著高于治疗获益组(13.16%)(P<0.05)。ROC曲线分析结果显示,TR、CEA、CYFRA 21-1、SCCAg、NSE及ProGRP单项检测判断肺癌化疗疗效的曲线下面积(AUC)分别为0.759、0.667、0.579、0.530、0.619、0.544。将各项指标进行组合,TR+CEA、TR+CEA+CYFRA21-1、TR+CEA+CYFRA21-1+NSE及TR+CEA+CYFRA 21-1+NSE+ProGRP联合检测判断肺癌化疗疗效的AUC分别为0.757、0.749、0.752和0.788。TR与CEA、NSE、SCC-Ag、CYFRA 21-1及ProGRP均无相关性(r值分别为0.05、0.02、-0.15、0.05、0.10,P>0.05)。结论TR或可作为更有效的肺癌疗效监测的生物标志物。 相似文献
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AbstractThe aim of this study is to clarify the possible association between methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism and pre-eclampsia in Hakka pregnant women in southern China. Pre-eclampsia and normal pregnant women were consecutively collected and MTHFR C677T genotypes were determined by the DNA sequencing method. One hundred and thirteen pre-eclampsia patients were CC homozygote (113 of 191, 59.2%), 68 of 191 (35.6%) were CT heterozygote, and 10 of 191 (5.2%) were TT homozygote, with the frequency of the T allele equal to 0.77. This is in comparison with the normal control group where 106 of 202 (52.5%) were CC homozygote, 83 of 202 (41.1%) were CT heterozygote, and 13 of 202 (6.4%) were TT homozygote, with the frequency of the T allele equal to 0.27. No statistically significant differences were observed in genotype or allele frequencies between the pre-eclampsia and normal control for the C677T polymorphism of MTHFR gene (p?>?.05). The findings of this study suggest that polymorphisms of MTHFR C677T genes were not associated with pre-eclampsia in Hakka pregnant women from southern China, but additional studies are necessary to explore the mechanisms involving it. 相似文献
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目的了解泸州市亚甲基四氢叶酸还原酶(MTHFR)基因多态性分布情况以及该单核苷酸多态性与复发性流产的相关性。方法选取2016-2018年在西南医科大学附属医院进行MTHFR基因检测的泸州汉族人群691例为研究对象,利用PCR-微阵列基因芯片法检测其C677T单核苷酸多态性,统计得出3种基因型的频率以及等位基因频率,并与全国其他地区已报道的多态性分布特征进行比较。结果泸州汉族人群CC、CT与TT基因型频率分别为39.2%、46.7%、14.0%,T等位基因频率为37.4%。其中女性T等位基因频率为38.1%,基因分布与纬度相近地区(N25°~31°)差异无统计学意义(P>0.05),与南方的海南、惠州及北方的西安、银川、赤峰、烟台人群差异有统计学意义(P<0.05)。在泸州育龄妇女中,复发性流产与MTHFR C677T基因多态性暂未发现存在直接关联。结论泸州地区汉族人群的MTHFR基因分布具有西南地区的分布特征,T等位基因频率整体呈现出随着纬度升高而升高的趋势。 相似文献
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目的 探究醛糖还原酶和晚期糖基化终末产物受体对糖尿病视网膜病变神经元凋亡的影响。方法 Wistar大鼠36只,随机分为对照组、模型组、转染组,后两组建立糖尿病大鼠模型。模型建立成功后,构建含有晚期糖基化终末产物受体siRNA的质粒并利用慢病毒转染入转染组大鼠体内。造模后4周、8周、12周,记录各组大鼠体质量及空腹血糖。造模后9周,禁食6 h,测定口服葡萄糖耐量。造模后12周,处死全部大鼠后,TUNEL法检测各组大鼠视网膜神经元凋亡情况,荧光分光光度计测定醛糖还原酶活性,Western blotting法测定晚期糖基化终末产物受体的表达,RT-PCR检测视网膜中Bcl-2和Bax mRNA相对表达量。结果 造模后4周、8周、12周,转染组和模型组的大鼠体质量均低于对照组(均为P<0.05);造模后12周,转染组大鼠体质量高于模型组(P<0.05)。造模后4周、8周、12周,各组内大鼠空腹血糖水平均无明显变化(均为P>0.05),转染组和模型组大鼠的空腹血糖水平均高于对照组(均为P<0.05)。模型组和转染组大鼠在口服葡萄糖后30 min时,血糖水平均高于对照组(均为P<0.05);在120 min时分别下降至最低,但仍高于对照组(均为P<0.05)。模型组和转染组的视网膜神经元凋亡指数、醛糖还原酶活性、晚期糖基化终末产物受体和Bax mRNA相对表达量均高于对照组(均为P<0.05),且转染组均高于模型组(均为P<0.05)。模型组和转染组的Bcl-2 mRNA相对表达量均低于对照组(均为P<0.05),转染组低于模型组(P<0.05)。结论 晚期糖基化终末产物结合受体后产生大量的氧自由基损伤,可能是导致糖尿病视网膜神经元凋亡,进而导致糖尿病视网膜病变发生的机制之一。 相似文献
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Francesca M Trovato Daniela Catalano Angela Ragusa G Fabio Martines Clara Pirri Maria Antonietta Buccheri Concetta Di Nora Guglielmo M Trovato 《World Journal of Nephrology》2015,4(1):127-137
AIM: To investigate the effects of different methylenetetrahydrofolate reductase(MTHFR) 677CT gene polymorphism and hyperhomocysteinemia for the development of renal failure and cardiovascular events, which are controversial.METHODS: We challenged the relationship, if any, of MTHFR 677CT and MTHFR 1298AC polymorphisms with renal and heart function. The present article is a reappraisal of these concepts, investigating within a larger population, and including a subgroup of dialysis patients, if the two most common MTHFR polymorphisms, C677 T and A1298 C, as homozygous, heterozygous or with a compound heterozygous state, show different association with chronic renal failure requiring hemodialysis. MTHFR polymorphism could be a favorable evolutionary factor, i.e., a protective factor for many ominous conditions, like cancer and renal failure. A similar finding was reported in fatty liver disease in which it is suggested that MTHFR polymorphisms could have maintained and maintain their persistence by an heterozygosis advantage mechanism. We studied a total of 630 Italian Caucasian subject aged 54.60 ± 16.35 years, addressing to the increased hazard of hemodialysis, if any, according to the studied MTHFR genetic polymorphisms. RESULTS: A favorable association with normal renal function of MTHFR polymorphisms, and notably of MTHFR C677 T is present independently of the negative effects of left ventricular hypertrophy, increased IntraRenal arterial Resistance and hyperparathyroidism. CONCLUSION: MTHFR gene polymorphisms could have a protective role on renal function as suggested by their lower frequency among our dialysis patients in end-stage renal failure; differently, the association with left ventricular hypertrophy and reduced left ventricular relaxation suggest some type of indirect, or concurrent mechanism. 相似文献
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Stagnant blood flow and organizing thrombus are intralesional components of patients with cerebral cavernous malformations (CCM). Stasis and inflammation are mechanisms of growth, lesional instability and acute hemorrhages with or w/o symptoms. We evaluate the association of pre-diagnostic aspirin and/or statin use with acute hemorrhages at diagnosis. Patients with a CCM diagnosis were identified and categorized according to their medications on admission into four groups (no therapy, statin, aspirin, combined). The primary outcome was an acute hemorrhage (with or w/o symptoms) at diagnosis reported in a standardized manner from the T2 weighted magnetic resonance image. A multivariate generalized linear mixed models (GLMM) was utilized to conduct per-lesion analysis. We identified 446 patients with 635 lesions. An acute hemorrhage at diagnosis was observed in 31% of the patients. There were 328 patients without statin or aspirin therapy, 34% of whom presented with acute hemorrhage. Of patients on aspirin therapy at diagnosis, 25% presented with hemorrhage. Of patients on statin therapy, 26% had a hemorrhage at diagnosis. Combined therapy in 44 patients demonstrated a lower proportion of patients with acute hemorrhages (7 patients, 16% incidence). A GLMM showed that patients in the combined therapy group to have significantly lower odds of having an acute hemorrhage at diagnosis compared to the reference group of no therapy (OR 0.24; 95% CI 0.09–0.59; P = 0.002). Patients with a CCM receiving therapy with both aspirin and statins were less likely to present at diagnosis with acute hemorrhage. 相似文献
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