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1.
杨旭  朱德兵  王巍炜  唐明伟 《西部医学》2022,34(9):1329-1334+1341
目的 分析术前SCC、CYFRA21-1与肺鳞癌临床病理特征、预后之间的关系。方法 收集2017年3月~2018年4月在云南省肿瘤医院确诊的肺鳞癌患者100例为观察组,确诊为肺良性肿瘤患者90名为肺良性肿瘤组、以及正常人群90名为健康人群组。通过电化学发光法对SCC、CYFRA21-1两种指标进行检测。检测SCC、CYFRA21-1含量,分析在肺鳞癌中表达的临床意义。结果 SCC、CYFRA21-1在肺鳞癌中比在肺良性肿瘤、健康人群中含量要高,差异有统计学意义(P<0.001),并且敏感性均高于其他两组;男性患者的SCC、CYFRA21-1含量高于女性患者,差异具有统计学意义(P<0.05);SCC、CYFRA21-1含量在年龄≥60岁的含量高于<60岁患者,差异无统计学意义(P>0.05);有吸烟史患者的SCC含量高于无吸烟史患者,差异无统计学意义(P>0.05)。CYFRA21-1在吸烟史患者中高表达,差异有统计学意义(P<0.05);SCC、CYFRA21-1在有淋巴结转移、远处转移、肿瘤直径≥5 cm、病理分期为晚期时高表达,差异具有统计学意义(P<0.05);SCC、CYFRA21-1阳性患者OS、PFS比阴性患者短;SCC、CYFRA21-1两者之间呈正相关,相关系数(r)为0.630。结论 SCC、CYFRA21-1在肺鳞癌中表达上调;SCC、CYFRA21-1与性别之间存在某种内在联系;SCC、CYFRA21-1与肺鳞癌的TNM分期呈正相关;SCC、CYFRA21-1阳性患者OS、PFS比阴性患者短;SCC、CYFRA21-1两者之间呈正相关,相关系数(r)为0.630。  相似文献   
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目的基于超高效液相色谱-离子阱-静电场轨道阱质谱(UPLC-LTQ-Orbitrap-MS)的分析方法鉴定葛根芩连汤中化学成分。方法采用色谱柱Dikma Endeavorsil C18(100 mm×2.1 mm,1.8μm),流动相为0.1%甲酸水(A)-乙腈(B),体积流量0.3 mL/min,梯度洗脱。质谱采用ESI源,正负离子模式分别采集一级、二级质谱数据。结果通过对照品指认、软件预测分析,结合文献报道,从葛根芩连汤中鉴定出67个化合物,包括黄酮类36个、生物碱类12个、三萜类及三萜皂苷类4个及其他15个。结论利用UPLC-LTQ-Orbitrap-MS系统阐明葛根芩连汤中化学成分,并初步归纳其各类主要化学成分的质谱裂解特点,为葛根芩根芩连汤的质量控制和作用机制研究提供了参考依据。  相似文献   
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Valuable diagnostic and prognostic biomarkers are urgently needed for colorectal cancer (CRC), which is one of the leading causes of mortality worldwide. Previous studies have reported altered expression of a mucin-like protein Fc fragment of IgG binding protein (FCGBP) in various types of cancer, but its potential diagnostic, prognostic and immunological roles in CRC remain to be determined. Therefore, the aim of current study was to investigate the potential roles of FCGBP in CRC. The present study investigated FCGBP mutations and changes in its expression levels using a combination of microarray and public dataset analyses, as well as immunohistochemistry. The results demonstrated a 10.5% mutation frequency in the FCGBP coding sequence in CRC tissues, and identified decreased FCGBP mRNA or protein expression levels in colorectal adenoma and CRC (compared with those in normal colorectal tissues from healthy control subjects), including pathologically advanced CRC (stage III+IV vs. I+II). Survival analysis using the GEPIA and Kaplan-Meier Plotter databases revealed that low FCGBP expression levels were associated with short overall, disease-free, relapse-free and event-free survival times in patients with CRC. Notably, analysis using the online Tumor IMmune Estimation Resource database revealed a positive correlation between FCGBP expression levels and the extent of infiltrating immune cells, such as B cells and dendritic cells. Consistently, the expression levels of most markers (51/57) for various types of immune cells were significantly correlated with FCGBP expression levels in CRC tissues. These findings suggested that FCGBP may serve as a diagnostic and prognostic biomarker, and that FCGBP may be associated with immune infiltration in CRC.  相似文献   
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The accumulation of abnormal prion protein (PrPSc) produced by the structure conversion of PrP (PrPC) in the brain induces prion disease. Although the conversion process of the protein is still not fully elucidated, it has been known that the intramolecular chemical bridging in the most fragile pocket of PrP, known as the “hot spot,” stabilizes the structure of PrPC and inhibits the conversion process. Using our original structure-based drug discovery algorithm, we identified the low molecular weight compounds that predicted binding to the hot spot. NPR-130 and NPR-162 strongly bound to recombinant PrP in vitro, and fragment molecular orbital (FMO) analysis indicated that the high affinity of those candidates to the PrP is largely dependent on nonpolar interactions, such as van der Waals interactions. Those NPRs showed not only significant reduction of the PrPSc levels but also remarkable decrease of the number of aggresomes in persistently prion-infected cells. Intriguingly, treatment with those candidate compounds significantly prolonged the survival period of prion-infected mice and suppressed prion disease-specific pathological damage, such as vacuole degeneration, PrPSc accumulation, microgliosis, and astrogliosis in the brain, suggesting their possible clinical use. Our results indicate that in silico drug discovery using NUDE/DEGIMA may be widely useful to identify candidate compounds that effectively stabilize the protein.Electronic supplementary materialThe online version of this article (10.1007/s13311-020-00903-9) contains supplementary material, which is available to authorized users.  相似文献   
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Human and equine rabies immunoglobulins are currently available for passive immunization against rabies. However, these are hampered by the limited supply and some drawbacks. Advances in antibody engineering have led to overcome issues of clinical applications and to improve the protective efficacy. In the present study, we report the generation of a trivalent single-chain Fv (scFv50AD1-Fd), that recognizes the rabies virus glycoprotein, genetically fused to the trimerization domain of the bacteriophage T4 fibritin, termed ‘foldon’ (Fd). scFv50AD1-Fd was expressed as soluble recombinant protein in bacterial periplasmic space and purified through affinity chromatography. The molecular integrity and stability were analyzed by polyacrylamide gradient-gel electrophoresis, size-exclusion chromatography and incubation in human sera. The antigen-binding properties of the trimeric scFv were analyzed by direct and competitive-ELISA. Its apparent affinity constant was estimated at 1.4 ± 0.25 × 109 M−1 and was 75-fold higher than its monovalent scFv (1.9 ± 0.68 × 107 M−1). The scFv50AD1-Fd neutralized rabies virus in a standard in vitro and in vivo neutralization assay. We showed a high neutralization activity up to 75-fold compared with monovalent format and the WHO standard serum. The gain in avidity resulting from multivalency along with an improved biological activity makes the trivalent scFv50AD1-Fd construct an important reagent for rabies protection. The antibody engineering approach presented here may serve as a strategy for designing a new generation of anti-rabies for passive immunotherapy.  相似文献   
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采用聚合酶链反应与限制性核酸内切酶HhaI消化相结合的方法建立一种简便。实用的人载脂蛋白E基因多态性检测方法。PCR扩增含有编码112和158位氨基酸的基因片断序列,产物经HhaⅠ酶消化,经聚丙烯酸 胺凝胶电泳可见2-4条特定长度的DNA条带易于判定apoE基因型。  相似文献   
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