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101.
目的 基于网络药理学研究香菇多糖抑制三阴乳腺癌(TNBC)的作用机制并采用细胞和动物实验进行验证。方法 通过GeneCards数据库和DisGeNET数据库筛选与TNBC相关基因靶点,利用TCMID、PubChem、SwissTargetPrediction和GeneCards数据库查询香菇多糖相关基因靶点。使用Sangerbox软件进行基因本体论(GO)富集和京都基因与基因组百科全书(KEGG)通路富集分析。结合STRING数据库与Cytoscape 3.7.0软件将共同靶点进行可视化处理,筛选核心靶点,构建"化合物-靶点-通路"网络。利用Metascape软件进行转录因子及相关调控基因特异富集。体外培养小鼠TNBC细胞4T1和人TNBC细胞MDA-MB-231,磺酰罗丹明B染色法观察香菇多糖(31.25、62.5、125、250、500、1 000μg·mL-1)对细胞存活率的影响;健康雌性BABLC小鼠sc接种1×106个4T1-Luc细胞构建TNBC模型,通过小动物活体成像系统观察香菇多糖(100、200 mg·kg-1)对肿瘤生长的影响,实时荧光定量PCR (qRT-PCR)技术检测肿瘤组织信号转导和转录活化因子3(STAT3)和血管内皮生长因子A (VEGFA) mRNA表达。结果 数据库及软件分析得到香菇多糖治疗TNBC关键靶点52个,靶点主要涉及PI3K-Akt、AGE-RAGE、HIF-1、MAPK信号通路和肿瘤蛋白多糖相关通路,PPI分析得到VEGFA、STAT3、MAPK1、IL2、TNF、RELA、AKT1、MAPK3、BCL2L1HSP90AA1 10个hub基因。与对照组比较,香菇多糖对4T1和MDA-MB-231细胞存活率均有显著抑制作用(P<0.05、0.01),且作用呈浓度相关性;在给药14、21d后,与模型组比较,香菇多糖能够剂量相关性地抑制小鼠TNBC肿瘤的生长,高剂量组差异显著(P<0.05、0.01),21 d抑制率达到(91.9±4.7)%;与对照组比较,香菇多糖给药后能够剂量相关性抑制STAT3和VEGFA的mRNA表达,高剂量组差异显著(P<0.05、0.01)。结论 香菇多糖可通过多靶点、多途径协同作用抑制TNBC的生长。  相似文献   
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设计了一种新型Fe-Ga合金磁特性测试装置。建立了该测试装置磁路部分三维有限元磁场分析模型,在该模型基础上通过调整结构和元件尺寸优化了磁路结构,并制作了样机。搭建了磁特性测试装置的实验平台,进行了Fe-Ga合金磁特性测试。实验结果表明,该装置可对Fe-Ga合金磁致伸缩棒材磁致伸缩效应和逆磁致伸缩效应进行静态、准静态和动态测量,测量结果与国外报道的结果一致。设计的磁特性测试装置具有稳定可靠、精度高、操作简单、自动记录等优点。该装置还适用于Fe-Ni、Fe-Co等饱和磁场低的磁致伸缩材料的磁特性测量。  相似文献   
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The aim of this study was to investigate the value of serum human epididymis protein 4 (HE4) and HE4 tissue protein expression to predict tumor resistance to adjuvant chemotherapy, progression‐free survival (PFS), and overall survival in patients with epithelial ovarian cancer (EOC). Consecutive inclusion of 198 patients diagnosed with EOC was conducted. Blood samples were collected prior to surgery and tissue samples during surgery. Patient data were registered prospectively in the Danish Gynecologic Cancer Database. The association between serum HE4 and HE4 tissue protein expression, resistance to adjuvant chemotherapy, PFS, and overall survival were analyzed in univariate analyses and in multivariate analyses adjusted for age, performance score, surgical outcome, stage, grade, and histological subtype. Serum HE4 levels predicted chemotherapy resistance, PFS, and overall survival correlated significantly (p < 0.001) in the univariate analyses; but after adjustment in a multivariate model, serum HE4 was insignificant, except in a subgroup analysis of postmenopausal women, where serum HE4 significantly predicted resistance to chemotherapy and progression‐free survival. HE4 tissue protein expression predicted PFS (p = 0.022) and overall survival (p = 0.047) in the univariate analysis, while HE4 tissue protein expression failed to predict these outcomes in the adjusted multivariate analyses. Serum HE4 or HE4 tissue protein expression are not independent factors of chemotherapy resistance or survival in patients with EOC, but serum HE4 might predict chemotherapy resistance and PFS in postmenopausal women.  相似文献   
106.
Delay of axon regeneration after peripheral nerve injury usually leads to progressive muscle atrophy and poor functional recovery. The Wnt/β-catenin signaling pathway is considered to be one of the main molecular mechanisms that lead to skeletal muscle atrophy in the elderly. We hold the hypothesis that the innervation of target muscle can be promoted by accelerating axon regeneration and decelerating muscle cell degeneration so as to improve functional recovery of skeletal muscle following peripheral nerve injury. This process may be associated with the Wnt/β-catenin signaling pathway. Our study designed in vitro cell models to simulate myelin regeneration and muscle atrophy. We investigated the effects of SB216763, a glycogen synthase kinase 3 beta inhibitor, on the two major murine cell lines RSC96 and C2C12 derived from Schwann cells and muscle satellite cells. The results showed that SB216763 stimulated the Schwann cell migration and myotube contraction. Quantitative polymerase chain reaction results demonstrated that myelin related genes, myelin associated glycoprotein and cyclin-D1, muscle related gene myogenin and endplate-associated gene nicotinic acetylcholine receptors levels were stimulated by SB216763. Immunocytochemical staining revealed that the expressions of β-catenin in the RSC96 and C2C12 cytosolic and nuclear compartments were increased in the SB216763-treated cells. These findings confirm that the glycogen synthase kinase 3 beta inhibitor, SB216763, promoted the myelination and myotube differentiation through the Wnt/β-catenin signaling pathway and contributed to nerve remyelination and reduced denervated muscle atrophy after peripheral nerve injury.  相似文献   
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109.
The purpose of this study attempted to analyze the potential risk factors for internal carotid artery injury during simple nasopharyngeal surgeries with or without an endoscopic aid. One hundred and seventy magnetic resonance imaging scans (340 halves) of the brain were retrospectively reviewed and studied. Anatomic variations of carotid arteries were classified, and various distances from the internal carotid arteries to the nasopharyngeal subsites were directly measured on the scans. The mean distances between the internal carotid arteries and nasopharyngeal subsites were significantly shortened in patients with nasopharyngeal internal carotid artery aberrancy, female gender, and lower body weight. The distance to the posterior nasopharyngeal wall was also shortened with age. However, the severity of nasopharyngeal carotid artery variations (kinking and coiling) did not reflect the shortening of mean distances to nasopharyngeal subsites. In conclusion, from multiple linear regression analysis, we found that the risk of an internal carotid artery injury during simple nasopharyngeal surgeries with or without an endoscopic aid is greatest in adult patients with nasopharyngeal carotid artery aberrancy, followed by female gender, lower body weight, and increasing age.  相似文献   
110.
目的观察日达仙稀释液对化疗后口腔溃疡患者的治疗作用。方法选择住院化疗后并发口腔溃疡患者68名,随机分为治疗组及对照组,治疗组用日达仙液涂抹溃疡面,对照组用锡类散涂抹溃疡面,观察两组间口腔溃疡疗效的差异。结果治疗组患者平均溃疡治愈时间(4.87±0.96)d及平均疼痛指数(3.84±1.21)分均明显低于对照组,差异均有统计学意义(t分别=7.55、5.46,P均<0.05)。结论日达仙稀释液对患者化疗后并发的口腔溃疡有较好疗效。  相似文献   
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