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991.
Alteration of human leukocyte antigen (HLA) expression, such as decreased HLA I (HLA‐A, ‐B and ‐C) antigens and elevated nonclassical HLA I antigens (HLA‐E, ‐F and ‐G), was reported to have an unfavorable prognosis in various cancers. In our study, HLA‐F expression in 105 primary esophageal squamous cell carcinoma (ESCC) lesions and 62 case‐matched adjacent normal tissues, and HLA I antigens among 68 cases were analyzed by immunohistochemistry. Data revealed that HLA‐F expression was observed in 58.1% (61/105) of the ESCC lesions and in 54.8% (34/62) of the normal esophageal tissues. Among the 62 case‐matched samples, HLA‐F expression (lesion vs. normal tissue) was upregulated, unchanged and downregulated in 13 (21.0%), 6 (9.6%) and 43 (69.4%) cases, respectively. Patients with HLA‐F positive had a worse survival than those with HLA‐F negative (p = 0.040). Patients with upregulated HLA‐F expression (lesion vs. normal tissue) had significantly worse survival than those with HLA‐F unchanged and downregulated (p = 0.010). Furthermore, decreased HLA I expression was observed in 41.2% (28/68) patients and was with worse prognosis in comparison to those with preserved HLA I expression (p = 0.001). Multivariate analysis using Cox's proportional hazards model revealed that upregulated HLA‐F expression (p = 0.026) and downregulated HLA I expression (p = 0.013) could be an independent unfavorable prognostic factor. In conclusion, our study provided the evidence that alteration of HLA I and HLA‐F antigen expression was associated with survival in patients with ESCC.  相似文献   
992.
目的 分析结直肠癌患者营养相关症状对营养状态的影响及其与全球营养不良领导倡议(GLIM)和生活质量的相关性.方法 本研究共纳入2013年6月至2018年12月多中心连续招募的结直肠癌患者2063例,进行营养不良诊断和生活质量评估,通过Logistic回归分析描述营养相关症状对营养状态的影响,并通过Spearman相关性...  相似文献   
993.
目的 研究吉西他滨作用于HepG2细胞后DR5、caspase-8、caspase-9、caspase-3的表达,以期探讨吉西他滨诱导HepG2细胞凋亡的机制.方法 应用MTT法和流式细胞仪体外研究吉西他滨对HepG2细胞增殖的影响;采用免疫细胞化学及Western blot法,观察吉西他滨作用于HepG2细胞24 h后DR5、caspase-8、caspase-9、caspase 3的表达情况.结果 吉西他滨对肝癌HepG2细胞的抑制作用呈时间和浓度依赖性;吉西他滨作用于HepG2细胞24 h后,细胞表面DR5及caspase-8、caspase-9、caspase-3的表达均增强.结论 吉西他滨诱导肝癌HepG2细胞凋亡的机制可能与其能够上调DR5及caspase-8、caspase-9、caspase-3的表达有关.  相似文献   
994.

Objectives

To test the influence of media injection in PET/CT on the functional or gross tumour volume measurement.

Patients and methods

Thirty-three patients (56 ± 19 years) with non-Hodgkin’s lymphoma (n = 22) or Hodgkin’s disease (n = 11) were prospectively studied at staging. PET/CTs were performed 60 min after injection of FDG. Iopamiron 300 (Iopamidol, 1.5 cc/kg) was injected immediately after, followed 50 s later by a second craniocaudal CT (CT+). PET images were successively reconstructed using the unenhanced CT (PET−) and the CT+ (PET+) for attenuation correction using iterative reconstruction (4 iterations, 8 subsets, 5 mm post-filtering). The SUVmax, SUVmean, SUVpeak and functional tumoural volume were measured in tumoural lymphadenopathies or malignant tissues (n = 56 VOIs) using 5 3D-thresholding methods on PET− and PET+ images: absolute SUV value of 2.5; 40% of SUVmax, and 3 adaptative thresholding methods (Vauclin, Black and Schaefer methods).

Results

The SUVmean and the volume measurement were significantly different (p < 0.001) for the five segmentation methods for PET− (p < 0.001) and PET+ (p < 0.001). The SUVmax, SUVmean and SUVpeak increased significantly in PET+ compared to PET− (2–5%). The SUVpeak was not significantly different for the five segmentation methods. The functional volume measurements were significantly different between PET− and PET+ only for the 2.5 segmentation method (+3%; p = 0.001), but not for the 40%, Vauclin, Black and Schaefer methods.

Conclusion

The functional volume could be measured in PET/CT when CT was performed with enhanced media. Caution should be taken when using the volume delineation method. Volume delineation methods using absolute threshold may artefactually increase the functional volume when enhanced CT is used for attenuation correction. The delineation volume using the relative or adaptative method should be preferred when contrast media are used for PET/CT.  相似文献   
995.
Objective: To study explores the effect of HLEC on the secreted proteins of epithelial ovarian cancer (EOC) cells (SKOV3-PM4) with directional highly lymphatic metastasis. Methods: Supernatants of four groups of cultured cells, namely, SKOV3 (A), SKOV3+HLEC (B), SKOV3-PM4 (C), SKOV3-PM4+HLEC (D), were collected, and their proteins were detected by antibody arrays and iTRAOcZD-LC-MALDI- TOF/TOF/MS. Significantly differential proteins were further analyzed via bioinformatics and validated in human serums and cell media via ELISA. Results: Results of antibody arrays and mass spectrometry demonstrated that GRN and VEGFA were upregulated in group C (compared with group A), whereas IGFBP7 and SPARC were downregulated in group D (compared with group C). Comprehensive bioinformatics analysis results showed that IGFBP7 and VEGFA were closely linked to each other. Further validation with serums showed statistical significance in VEGFA and IGFBP7 levels among groups of patients with ovarian cancers, benign tumors, and control groups. Two proteins were upegulated in the first group. VEGFA in the control group was downregulated. For IGFBP, upregulation in the control group and down-regulation in the first group were also observed. Conclusion: The HLEC microenvironment is closely associated with directional metastasis to lymph nodes and with differential proteins including cell stromal proteins and adhesion factors. The upregulation of VEGFA and GRN and the downregulation of SPARC and IGFBP7 are closely associated with directional metastasis to lymph nodes in EOC cells.  相似文献   
996.
BackgroundPrevious studies have shown successful antitumor effects of systemically delivered double-deleted vaccinia virus (vvDD) against a number of adult tumor models, including glioma, colon and ovarian cancers. The purpose of this study was to investigate the oncolytic potential of vvDD against a panel of cell lines representative of pediatric solid tumors that are currently difficult to cure.MethodsCell lines derived from central nervous system atypical teratoid rhabdoid tumor (AT/RT) (BT12, BT16 and KCCF1), sarcoma (143B, HOS, RD and RH30), and neuroblastoma (SKNAS, SKNBE2, IMR-5 and IMR-32) were examined for vvDD mediated cytotoxicity defined by virus expansion followed by loss of tumor cell viability. The normal human fibroblast cell line HS68 was used as a control. Next, relevant orthotopic, subcutaneous and lung metastasis xenograft models were treated with intravenous doses of live vvDD or killed virus controls (DV). Tumor growth inhibition and viral replication were quantified and survival outcomes of these animals were assessed.ResultsvvDD was able to infect and kill nine of eleven of the pediatric tumor cells (81.8%) in vitro. In xenograft models, intravenous administration of a single dose of vvDD significantly inhibited the growth of tumors and prolonged the survival of intracranial and metastatic tumors.ConclusionsOncolytic vvDD administered i.v. shows activity in preclinical models of pediatric malignancies that are resistant to many currently available treatments. Our data support further evaluation of vvDD virotherapy for refractory pediatric solid tumors.  相似文献   
997.
目前对"双轨合一"临床专业硕士研究生培养计划缺乏完整统一的内容和要求,本文以中医学主干学科《针灸学》为例,制定了亚专科层面统一的教学培养方案细则,在方案中明确了教学管理构建,创新了教学方法和考核办法.我们将以制定单一亚专科层面的规范化培训教学培养方案为基础,再逐步形成多学科人才培养方案体系,以期培养合格优秀的规范化培训住院医师.  相似文献   
998.
本文对99例复发性口疮患者,分别在初诊治疗前(发作期)和治疗后3月未发作时进行唾液SIgA、IgG、IgM、C3、C4及溶菌酶含量和活性检测,并以45名健康学生唾液相应成份作为正常对照。实验结果表明:复发性口疮患者治疗前唾液SIgA、IgG、IgM、C3、C4及溶菌酶含量和活性,均远远低于正常人唾液相应成份(P<0.01);复发性口疮患者治疗后,其唾液SIgA、IgG、IgM、C3、C4及溶菌酶含量和活性,均较治疗前有显著提高(P<0.01),其中IgG、C4及溶菌酶含量和活性恢复较明显,与正常人唾液相应成份相似(P>0.05)。  相似文献   
999.
1000.
Independent component analysis (ICA) is a potential spatial filtering method for the implementation of motor imagery brain-computer interface (MIBCI). However, ICA-based MIBCI (ICA-MIBCI) is sensitive to electroencephalogram (EEG) channels and the quality of the training data, which are two crucial factors affecting the stability and classification performance of ICA-MIBCI. To address these problems, this paper is mainly focused on the investigation of EEG channel optimization. As a reference, we constructed a single-trial-based ICA-MIBCI system with commonly used channels and common spatial pattern-based MIBCI (CSP-MIBCI). To minimize the impact of artifacts on EEG channel optimization, a data-quality evaluation method, named “self-testing” in this paper, was used in a single-trial-based ICA-MIBCI system to evaluate the quality of single trials in each dataset; the resulting self-testing accuracies were used for the selection of high-quality trials. Given several candidate channel configurations, ICA filters were calculated using selected high-quality trials and applied to the corresponding ICA-MIBCI implementation. Optimal channels for each dataset were assessed and selected according to the self-testing results related to various candidate configurations. Forty-eight MI datasets of six subjects were employed in this study to validate the proposed methods. Experimental results revealed that the average classification accuracy of the optimal channels yielded a relative increment of 2.8% and 8.5% during self-testing, 14.4% and 9.5% during session-to-session transfer, and 36.2% and 26.7% during subject-to-subject transfer compared to CSP-MIBCI and ICA-MIBCI with fixed the channel configuration. This work indicates that the proposed methods can efficiently improve the practical feasibility of ICA-MIBCI.  相似文献   
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