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本研究选取病理科收集的自2016年1月至2016年12月的90例术后胃癌组织标本(胃癌组)、45例癌旁组织标本(对照组),采用免疫组化染色法检测两组标本中的Y框蛋白(Sox2)、胶原三股螺旋重叠蛋白-1表达,并分析其与肿瘤TNM分期、淋巴结转移、浸润深度、分化程度的关系,采用Spearman秩相关检验检测两种蛋白的相互关系,试图探讨胃癌患者癌组织中性别决定区Y框蛋白(Sox2)、胶原三股螺旋重叠蛋白-1(CTHRC-1)的表达及其相关性。研究结果表明:胃癌组的Sox2蛋白阳性表达率63.33%显著低于对照组的93.33%(p<0.05),胃癌组的CTHRC-1蛋白阳性表达率78.89%显著高于对照组的24.44%(p<0.05);胃癌组的Sox2蛋白阳性表达与胃癌的分化程度、发生淋巴结转移具有相关性(p<0.05);胃癌组的CTHRC-1蛋白阳性表达与胃癌的淋巴结转移、TNM分期、肿瘤浸润深度具有显著的相关性(p<0.05);胃癌组的Sox2蛋白与CTHRC-1蛋白呈显著的负相关表达(Spearman相关系数r=-0.322, p=0.002<0.05)。本研究的初步结论表明:胃癌组织中Sox2蛋白低表达和CTHRC-1蛋白高表达,并且与肿瘤发展密切相关,且二者表达呈负相关。 相似文献
43.
Guoxin Zhang Hongli Li Ruimei Sun Peirui Li Zhiyi Yang Yuanyuan Liu Zhaoyan Wang Yuling Yang Chonggao Yin 《Journal of cellular and molecular medicine》2019,23(5):3271-3279
The triple‐negative breast cancer is the most malignant type of breast cancer. Its pathogenesis and prognosis remain poor despite the significant advances in breast cancer diagnosis and therapy. Meanwhile, long noncoding RNAs (LncRNAs) play a pivotal role in the progression of malignant tumors. In this study, we found that LncRNA‐ZEB2‐AS1 was dramatically up‐regulated in our breast cancer specimens and cells (MDA231), especially in metastatic tumor specimens and highly invasive cells, and high lncRNA‐ZEB2‐AS1 expression is associated with clinicopathologic features and short survival of breast cancer patients. LncRNA‐ZEB2‐AS1 promotes the proliferation and metastasis of MDA231 cells in SCID mice. Thus, it is regarded as an oncogene in triple‐negative breast cancer. It is mainly endo‐nuclear and situated near ZEB2, positively regulating ZEB2 expression and activating the epithelial mesenchymal transition via the PI3K/Akt/GSK3β/Zeb2 signaling pathway. Meanwhile, EGF‐induced F‐actin polymerization in MDA231 cells can be suppressed by reducing lncRNA‐ZEB2‐AS1 expression. The migration and invasion of triple‐negative breast cancer can be altered through cytoskeleton rearrangement. In summary, we demonstrated that lncRNA‐ZEB2‐AS1 is an important factor affecting the development of triple‐negative breast cancer and thus a potential oncogene target. 相似文献
44.
Hong Yuan Hong‐Jie Peng Bo‐Quan Li Jin Xie Long Kong Meng Zhao Xiao Chen Jia‐Qi Huang Qiang Zhang 《Liver Transplantation》2019,9(1)
Rechargeable lithium–sulfur batteries have attracted tremendous scientific attention owing to their superior energy density. However, the sulfur electrochemistry involves multielectron redox reactions and complicated phase transformations, while the final morphology of solid‐phase Li2S precipitates largely dominate the battery's performance. Herein, a triple‐phase interface among electrolyte/CoSe2/G is proposed to afford strong chemisorption, high electrical conductivity, and superb electrocatalysis of polysulfide redox reactions in a working lithium–sulfur battery. The triple‐phase interface effectively enhances the kinetic behaviors of soluble lithium polysulfides and regulates the uniform nucleation and controllable growth of solid Li2S precipitates at large current density. Therefore, the cell with the CoSe2/G functional separator delivers an ultrahigh rate cycle at 6.0 C with an initial capacity of 916 mAh g?1 and a capacity retention of 459 mAh g?1 after 500 cycles, and a stable operation of high sulfur loading electrode (2.69–4.35 mg cm?2). This work opens up a new insight into the energy chemistry at interfaces to rationally regulate the electrochemical redox reactions, and also inspires the exploration of related energy storage and conversion systems based on multielectron redox reactions. 相似文献
45.
目的:探讨肾衰宁胶囊联合血液透析对慢性肾功能衰竭患者肾功能及血液流变学的影响。方法:选取中国医科大学本溪中心医院于2015年1月-2017年9月期间收治的慢性肾功能衰竭患者80例为研究对象。根据随机数字表法将患者分为对照组(n=40)与研究组(n=40),两组患者均给予血液透析治疗,研究组在此基础上联合使用肾衰宁胶囊治疗,疗程均为3个月。观察并比较两组患者治疗3个月后临床疗效及不良反应发生情况,比较两组患者治疗前、治疗3个月后血肌酐(Scr)、尿素氮(BUN)、肾小球滤过率(eGFR)水平及全血高切黏度、全血低切黏度、血浆黏度、红细胞比容。结果:研究组患者总有效率为92.50%(37/40),高于对照组的67.50%(27/40),差异有统计学意义(P0.05)。两组患者治疗3个月后Scr、BUN水平较治疗前降低,且研究组低于对照组(P0.05);而两组患者治疗3个月后eGFR水平较治疗前升高,且研究组高于对照组(P0.05)。研究组患者治疗3个月后的全血高切黏度、全血低切黏度、血浆黏度以及红细胞比容均低于对照组(P0.05)。对照组不良反应发生率为7.50%,与研究组的10.00%比较差异无统计学意义(P0.05)。结论:肾衰宁胶囊联合血液透析对慢性肾功能衰竭患者有较好的治疗效果,能够改善患者肾功能状况,同时稳定患者血液流变学,并且安全性较好。 相似文献
46.
目的:探讨透明质酸钠联合硫酸氨基酸葡萄糖钾胶囊对踝关节损伤患者血清骨性标志物水平及关节功能的影响。方法:选择2015年1月至2017年1月在我院接受治疗的120例踝关节损伤患者,将其随机分为观察组和对照组,每组各60例。对照组患者采用透明质酸钠联治疗,观察组则在对照组治疗方案的基础上联合硫酸氨基酸葡萄糖钾胶囊进行治疗。检测和比较两组患者治疗前后血清骨钙素(BGP)、I型前胶原羧基端肽(PICP)、骨源性碱性磷酸酶(BALP)水平及Baird-Jackson踝关节评分的变化情况及治疗后的临床疗效。结果:治疗后,观察组的总有效率(91.67%)明显高于对照组(78.33%,P0.05)。两组患者治疗后的血清BGP、PICP、BALP水平及Baird-Jackson踝关节评分均较治疗前显著升高,且观察组明显高于对照组(P0.05)。两组治疗过程中均无明显不良反应发生。结论:透明质酸钠联合硫酸氨基酸葡萄糖钾胶囊治疗踝关节损伤患者的临床疗效显著优于单用透明质酸钠联治疗,其可有效改善血清骨性标志物水平,且利于踝关节功能的恢复。 相似文献
47.
Philip A. Stephens Marcus V. Vieira Stephen G. Willis Chris Carbone 《Ecology letters》2019,22(4):654-663
We address two fundamental ecological questions: what are the limits to animal population density and what determines those limits? We develop simple alternative models to predict population limits in relation to body mass. A model assuming that within‐species area use increases with the square of daily travel distance broadly predicts the scaling of empirical extremes of minimum density across birds and mammals. Consistent with model predictions, the estimated density range for a given mass, ‘population scope’, is greater for birds than for mammals. However, unlike mammals and carnivorous birds, expected broad relationships between body mass and density extremes are not supported by data on herbivorous and omnivorous birds. Our results suggest that simple constraints on mobility and energy use/supply are major determinants of the scaling of density limits, but further understanding of interactions between dietary constraints and density limits are needed to predict future wildlife population responses to anthropogenic threats. 相似文献
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49.
Hepatocyte growth factor induces epithelial cell motility through transactivation of the epidermal growth factor receptor 总被引:3,自引:0,他引:3
Hepatocyte growth factor (HGF) is a potent inducer of motility in epithelial cells. Since we have previously found that activation of the epidermal growth factor receptor (EGFR) is an absolute prerequisite for induction of motility of corneal epithelial cells after wounding, we investigated whether induction of motility in response to HGF is also dependent on activation of the EGFR. We now report that HGF induces transactivation of the EGFR in an immortalized line of corneal epithelial cells, in human skin keratinocytes, and in Madin-Darby canine kidney cells. EGFR activation is unconditionally required for induction of motility in corneal epithelial cells, and for induction of a fully motile phenotype in Madin-Darby canine kidney cells. Activation of the EGFR occurs through amphiregulin and heparin-binding epidermal growth factor-like growth factor. Early after HGF stimulation, blocking EGFR activation does not inhibit extracellular-signal regulated kinase 1/2 (ERK1/2) activation by HGF, but the converse is seen after approximately 1 h, indicating the existence of EGFR-dependent and -independent routes of ERK1/2 activation. In summary, HGF induces transactivation of the EGFR in epithelial cells, and this is a prerequisite for induction of full motility. 相似文献
50.