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Influence of Fe on Microstructure and Mechanical Properties in Pdoped Ni–Cr–Fe Alloys
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作者 Xin-Tong Lian Wen-Ru Sun +2 位作者 Xin Xin Fang Liu Dan-Dan Zheng 《金属学报:英文版》 SCIE EI CAS CSCD 2019年第6期771-779,共9页
The influence of Fe on the microstructure and mechanical properties of P-doped Ni–Cr–Fe alloys has been investigated.Results showed that increasing Fe content refined the dendrite microstructure and enhanced the sol... The influence of Fe on the microstructure and mechanical properties of P-doped Ni–Cr–Fe alloys has been investigated.Results showed that increasing Fe content refined the dendrite microstructure and enhanced the solubility of P in as-cast alloys.The change of microhardness in different dendrite regions was attributed to the segregation of P atoms in solid solution state,which had strengthening effects.Increasing Fe contents from 15.2 to 60.7 wt%reduced the yield strength and tensile strength but had little influence on the elongation of alloys.The stress rupture life of alloys after heat treatment decreased with the increment of Fe contents,and the failure fracture modes transferred from transgranular to intergranular fracture mode.The change of fracture modes was due to the weakness of grain boundaries caused by the increment of Fe.In addition,the precipitation of M23C6 was believed to be related to the segregation of P toward grain boundaries,which led to the fluctuation of carbon and chromium atoms near the grain boundaries in alloys with low Fe contents.Consequently,the increment of Fe decreased the strength of matrix and changed the existence of P atoms and the precipitates at grain boundaries. 展开更多
关键词 FE P SEGREGATION PRECIPITATE MECHANICAL PROPERTIES
Effects of Phosphorus and Iron on Microstructures and Mechanical Properties in NiCrFe-Based Alloys
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作者 Xin-Tong Lian Wen-Ru Sun +2 位作者 Fang Liu Dan-Dan Zheng Xin Xin 《金属学报:英文版》 SCIE EI CAS CSCD 2019年第5期659-667,共9页
The microstructures and mechanical properties, especially creep properties, of the NiCrFe-based alloys with various contents of phosphorus and iron were investigated. The results showed that the tensile yield strength... The microstructures and mechanical properties, especially creep properties, of the NiCrFe-based alloys with various contents of phosphorus and iron were investigated. The results showed that the tensile yield strength decreased with increasing iron contents while had no obvious change with the addition of phosphorus. For creep properties, the alloy with15.8 wt% iron and 0.09 wt% phosphorus possessed the longest creep life(679 h) among all alloys. Only M23C6 was formed in the alloys with low phosphorus contents, while both intergranular M3P and M23C6 precipitated with the increment of phosphorus, which enhanced the strength of grain boundary by hindering the movements of dislocations during creep tests. The reasons for the enhancement of creep life were mainly related to the solid solution strengthening effect of phosphorus and optimization of grain boundary precipitations by phosphorus. 展开更多
关键词 NiCrFe-based alloys PHOSPHORUS IRON MICROSTRUCTURES CREEP properties
A complicated case of innominate and right common arterial aneurysms due to Takayasu’s arteritis 预览
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作者 Wen-Da Wang Rui Sun +3 位作者 Meng-Xin Zhou Xing-Rong Liu Yue-Hong Zheng Yue-Xin Chen 《世界临床病例杂志》 2019年第13期1671-1676,共6页
BACKGROUND Innominate artery aneurysms (IAAs) are relatively rare. Endovascular therapy has been an alternative to open surgery in some IAA cases, but open repair is still necessary in complicated cases. CASE SUMMARY ... BACKGROUND Innominate artery aneurysms (IAAs) are relatively rare. Endovascular therapy has been an alternative to open surgery in some IAA cases, but open repair is still necessary in complicated cases. CASE SUMMARY We report a 35-year-old female who suffered from Takayasu’s arteritis. The patient did not get regular treatment, and IAA and right common carotid artery aneurysm developed, which complicated with occlusion of the left carotid artery, subclavian artery, and the initial part of the left vertebral artery. The patient also had moderate aortic valve insufficiency. With inflammation being controlled well, the patient received the surgery for arterial aneurysms of innominate and right common carotid arteries and aortic valve insufficiency. The shunts for cerebral blood supply were designed to protect the brain and the surgery was conducted successfully under extracorporeal circulation. CONCLUSION The case illustrates that open surgery may be appropriate for some complicated IAAs, and brain protection is important. 展开更多
关键词 CASE report Innominate artery ANEURYSM Takayasu's ARTERITIS SHUNTS Brain protection
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膦甲酸钠与喷昔洛韦治疗带状疱疹的疗效比较
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作者 陈晶晶 徐丰 +4 位作者 施辛 郑聪聪 凌昕 杨志刚 闫志华 《中国皮肤性病学杂志》 CAS CSCD 北大核心 2019年第3期297-300,共4页
目的比较膦甲酸钠与喷昔洛韦治疗带状疱疹的疗效。方法选择在四个中心就诊符合诊断标准的带状疱疹患者为研究对象,采用随机、平行对照的临床试验。治疗组患者采用膦甲酸钠氯化钠注射液3.0 g,1次/12 h,静脉滴注,连用7 d。对照组患者采用... 目的比较膦甲酸钠与喷昔洛韦治疗带状疱疹的疗效。方法选择在四个中心就诊符合诊断标准的带状疱疹患者为研究对象,采用随机、平行对照的临床试验。治疗组患者采用膦甲酸钠氯化钠注射液3.0 g,1次/12 h,静脉滴注,连用7 d。对照组患者采用注射用喷昔洛韦0.25 g,1次/12 h,静脉滴注,连用7 d。用药后第3、7、14天观察疗效。结果共入组226例,治疗后第3、7、14天,治疗组的有效率分别为19.30%、67.54%和93.86%,对照组分别为18.75%、65.18%和91.07%,两组有效率比较差异无统计学意义(P>0.05);治疗组止疱时间、水疱完全结痂时间、结痂全部脱落时间均短于对照组,但差异无统计学意义(P均>0.05);疼痛改变(NRS法分值)比较两组间差异无统计学意义(P>0.05)。治疗组有10例、对照组有11例出现PHN,差异无统计学意义(P>0.05)。结论膦甲酸钠与喷昔洛韦治疗带状疱疹的疗效相当。 展开更多
关键词 膦甲酸钠 喷昔洛韦 带状疱疹 疗效 比较
Automated quantification of Ki-67 index associates with pathologic grade of pulmonary neuroendocrine tumors
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作者 Hai-Yue Wang Zhong-Wu Li +5 位作者 Wei Sun Xin Yang Li-Xin Zhou Xiao-Zheng Huang Ling Jia Dong-Mei Lin 《中华医学杂志:英文版》 SCIE CAS CSCD 2019年第5期551-561,共11页
Background: Classification of the pulmonary neuroendocrine tumor (pNET) categories is a step-wise process identified by presence of necrosis and number of mitoses per 2 mm^2. In neuroendocrine tumor pathology, Ki-67 w... Background: Classification of the pulmonary neuroendocrine tumor (pNET) categories is a step-wise process identified by presence of necrosis and number of mitoses per 2 mm^2. In neuroendocrine tumor pathology, Ki-67 was first described as a prognostic factor in the pancreas and incorporated into the grading system of digestive tract neuroendocrine neoplasms in the 2010 WHO classification. However, the significance of Ki-67 in pNETs was still a controversial issue. This study was to investigate the potentially diagnostic value of Ki-67 in pNETs. Methods: We retrieved 159 surgical specimens of pNETs, including 35 typical carcinoids (TCs), 2 atypical carcinoid (ACs), 28 largecell neuroendocrine carcinomas (LCNECs), 94 small-cell lung cancers (SCLCs). Manual conventional method (MCM) and computer-assisted image analysis method (CIAM) were used to calculate the Ki-67 proliferative index. In CIAM, 6 equivalent fields lly annotated for digital image analysis. Results: The Ki-67 index among the 4 groups with ranges of 0.38% to 12.66% for TC, 4.34% to 29.48% for AC, 30.67% to 93.74% for LCNEC, and 40.71% to 96.87% for SCLC. The cutoff value of Ki-67 index to distinguish low grade with high grade was 30.07%. For the univariate survival analyses in pNETs, both the overall survival and progression-free survival correlated with Ki-67 index. In addition, the Ki-67 index performed by CIAM was proved to be of great positive correlation with MCM.(500 ×500 μm) at 10× magnification were manua Conclusions: Ki-67 index counted by CIAM is a reliable method and can be a useful adjunct to classify the low- and high-grade NETs. 展开更多
关键词 Antigen KI-67 COMPUTER-ASSISTED numerical analysis NEUROENDOCRINE tumor PROGNOSTIC factor
Combustion characteristics of unburned pulverized coal and its reaction kinetics with CO2 预览
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作者 Dong-wen Xiang Feng-man Shen +4 位作者 Jia-long Yang Xin Jiang Hai-yan Zheng Qiang-jian Gao Jia-xin Li 《矿物冶金与材料学报:英文版》 SCIE EI CAS CSCD 2019年第7期811-821,共11页
The combustion characteristics of two kinds of unburned pulverized coal (UPC) made from bituminous coal and anthracite were investigated by thermogravimetric analysis under air. The reaction kinetics mechanisms betwee... The combustion characteristics of two kinds of unburned pulverized coal (UPC) made from bituminous coal and anthracite were investigated by thermogravimetric analysis under air. The reaction kinetics mechanisms between UPC and CO2 in an isothermal experiment in the temperature range 1000–1100°C were investigated. The combustion performance of unburned pulverized coal made from bituminous coal (BUPC) was better than that of unburned pulverized coal made from anthracite (AUPC). The combustion characteristic indexes (S) of BUPC and AUPC are 0.47 × 10^-6 and 0.34 × 10^-6 %2·min^-2·°C^-3, respectively, and the combustion reaction apparent activation energies are 91.94 and 102.63 kJ·mol^-1, respectively. The reaction mechanism of BUPC with CO2 is random nucleation and growth, and the apparent activation energy is 96.24 kJ·mol^-1. By contrast, the reaction mechanism of AUPC with CO2 follows the shrinkage spherical function model and the apparent activation energy is 133.55 kJ·mol^-1. 展开更多
关键词 unburned pulverized COAL COMBUSTION characteristics REACTIVITY REACTION mechanism APPARENT ACTIVATION energy
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Construction of plant expression vector of adketo gene driven by a tomato fruit-special promoter
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作者 Xin-Jun Chen Jing Huang +2 位作者 Wei Li Ke-Yan Zhong Xin-Zheng Gao 《海南医科大学学报(英文版)》 2019年第2期11-14,共4页
Objective:To construct the plant expression vector including Adketo gene from Adonis aestivalis and E8 promotor, and provide a new way for astaxanthin production by plant genetic engineering.Methods: The Adketo gene w... Objective:To construct the plant expression vector including Adketo gene from Adonis aestivalis and E8 promotor, and provide a new way for astaxanthin production by plant genetic engineering.Methods: The Adketo gene was clonied from Adonis aestivalis by RT-PCR and the 1.1 kb tomato E8 gene was amplified by PCR. then cloned into T vector.After the preliminary identification by Microbial PCR, the recombinant T- vectors were subjected to sequence analysis. Cut the E8 promoter and Adketo gene and inserted into the plant binary expression vector pBI121to obtain the recombinant expression vector. And then to identify the vector by microbial PCR detection and enzyme digestion.Results: Sequencing results analysis showed the right E8 and Adketo gene sequences, the identification by microbial PCR and digestion with restriction enzymes proved that the recombinant vector had the inserts with expected length of target fragments.Conclusion: The plant expression vector containing Adketo gene driven by fruit specific promoter E8 was successfully constructed. 展开更多
关键词 Adketo GENE EXPRESSION VECTOR E8 PROMOTER
Significance of HER2 protein expression and HER2 gene amplification in colorectal adenocarcinomas 预览
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作者 Xin-Yu Wang Zhi-Xue Zheng +6 位作者 Yu Sun Yan-Hua Bai Yun-Fei Shi Li-Xin Zhou Yun-Feng Yao Ai-Wen Wu Deng-Feng Cao 《世界胃肠肿瘤学杂志:英文版(电子版)》 CAS 2019年第4期335-347,共13页
BACKGROUND Human epidermal growth factor receptor 2 (HER2) is an oncogenic driver, and a well-established therapeutic target in breast and gastric cancers. While the role of HER2 as a prognostic biomarker in colorecta... BACKGROUND Human epidermal growth factor receptor 2 (HER2) is an oncogenic driver, and a well-established therapeutic target in breast and gastric cancers. While the role of HER2 as a prognostic biomarker in colorectal adenocarcinomas (CRCs) remains uncertain, its relevance as a therapeutic target has been established. We undertook the present study to evaluate the frequency of HER2 expression in CRC and to correlate it with various clinicopathological variables. AIM To correlate HER2 protein expression and HER2 gene amplification with clinicopathological features and survival in surgically resected CRC. METHODS About 1195 consecutive surgically resected CRCs were analyzed by immunohistochemical staining (IHC) to assess HER2 protein expression, and 141 selected tumors were further evaluated by fluorescence in situ hybridization (FISH) to assess HER2 gene amplification. Follow-up information was available for 1058 patients, and using this information we investigated the prevalence of HER2 protein overexpression and gene amplification in a large series of surgically resected CRCs, and evaluated the relationship between overexpression and clinicopathological parameters and prognosis. RESULTS HER2 IHC scores of 3+, 2+, 1+, and 0 were seen in 31 (2.6%), 105 (8.8%), 475 (39.7%), and 584 (48.9%) tumors, respectively. HER2 gene amplification was seen in 24/29 tumors with an IHC score of 3+(82.8%;unreadable in 2/31), 12/102 tumors with an IHC score of 2+(11.8%;unreadable in 2/104), and 0 tumors with IHC score of 1+(0/10). HER2 gene amplification was seen in 36/1191 tumors (3.0%;unreadable in 4/1195). Among the tumors with HER2 IHC scores of 3+ and 2+, the mean percentage of tumor cells with positive IHC staining was 90%(median 100%, range 40%-100%) and 67%(median 75%, range 5%-95%), respectively (P < 0.05). Among tumors with IHC scores of 2+, those with HER2 gene amplification had a higher number of tumors cells with positive IHC staining (n = 12, mean 93%, median 95%, range 90%-95%) than those without (n = 90, mean 70%, 展开更多
关键词 Human EPIDERMAL growth factor receptor 2 IMMUNOHISTOCHEMICAL STAINING Fluorescent in SITU HYBRIDIZATION Prognosis Colorectal CANCERS
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基于小波包分解与机器学习的汽车调光电机异音识别 预览 被引量:1
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作者 张新 郑燕萍 +1 位作者 Antoine AUGEIX 郑晓娇 《森林工程》 2019年第1期59-63,112共6页
为实现汽车调光电机装置异音检测的自动化,本文采用机器学习的方法开展产品异音识别研究。在分析确定产品异音来源的基础上,采集正常件和异音件的振动信号,利用小波包分解,结合时频域分析,在能量谱和时域特征中提取10个特征向量,基于BP... 为实现汽车调光电机装置异音检测的自动化,本文采用机器学习的方法开展产品异音识别研究。在分析确定产品异音来源的基础上,采集正常件和异音件的振动信号,利用小波包分解,结合时频域分析,在能量谱和时域特征中提取10个特征向量,基于BP神经网络对200个信号样本进行机器学习分类。并对20个样件进行试验,识别汽车调光电机异音的正确率达到96.7%。研究表明,采用机器学习的方法能够有效地识别电机异音,此研究具有工程应用价值。 展开更多
关键词 调光电机装置 异音识别 机器学习 支持向量机 小波包
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王琦“痰湿调体方”干预痰湿体质效果评价 预览
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作者 王鑫 王济 +8 位作者 李玲孺 郑燕飞 白明华 李英帅 张妍 侯淑涓 杨正 姚海强 王琦 《天津中医药》 CAS 2019年第4期319-321,共3页
[目的]通过临床观察王琦教授专利方“痰湿调体方”干预痰湿体质的效果,探讨调理痰湿体质在代谢性慢病防治中的作用,为制定痰湿体质干预效果评价标准提供依据。[方法]受试者为18~65岁北京市自然人群,在2018年6月-2018年10月期间填写《王... [目的]通过临床观察王琦教授专利方“痰湿调体方”干预痰湿体质的效果,探讨调理痰湿体质在代谢性慢病防治中的作用,为制定痰湿体质干预效果评价标准提供依据。[方法]受试者为18~65岁北京市自然人群,在2018年6月-2018年10月期间填写《王琦九种中医体质量表》,按照中华中医药学会《中医体质分类与判定》标准进行体质判定,结合人工体质辨识,纳入单纯痰湿体质者32例,以“痰湿调体方”干预8周,干预前后测量体质量、腰围、体重指数(BMI),采集静脉血检测血糖、血脂等生化指标,并重测痰湿体质评分。[结果]经“痰湿调体方”干预后,受试者痰湿体质量化评分降低,症状明显改善,与干预前相比,差异有统计学意义(P<0.05);体质量、腰围、BMI、血红蛋白(HbA1c)、载脂蛋白A(ApoA)、甘油三酯(TG)、低密度脂蛋白(LDL)较干预前明显下降(P<0.05)。[结论]“痰湿调体方”可明显降低痰湿体质评分,有效改善体质偏颇程度和相关临床指标。 展开更多
关键词 痰湿体质 痰湿调体方 调体干预 效果评价
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Analysis of the characteristics of diabetic peripheral nerve damage by high frequency ultrasound combined with QTT
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作者 Pei Hu Bin Xiao +5 位作者 Rui Xue De-Jiao Sun Zheng-Sen Dong Tian-Xin Hu Jia-Jing Wang Guang-Mei Zheng 《海南医科大学学报(英文版)》 2019年第7期15-20,共6页
Objective: High frequency ultrasound combined with policy thermal perception testing (QTT) was used to analyze the characteristics of nerve damage in diabetic peripheral neuropathy (DPN), and then provided the basis f... Objective: High frequency ultrasound combined with policy thermal perception testing (QTT) was used to analyze the characteristics of nerve damage in diabetic peripheral neuropathy (DPN), and then provided the basis for the clinical prevention, diagnosis and treatment of DPN. Methods: A total of 110 DPN patients admitted to the hospital from December 2015 to May 2018 were selected, and the characteristics of nerve damage in diabetic peripheral neuropathy were analyzed by ultrasound and QTT. Results: In the results of QTT, the abnormal proportion of the CDT, WDT, CPT and HPT of the lower limbs in DPN's were all higher than the upper limbs;The difference of WDT and HPT in the age and course groups of patients in the upper limbs was statistically significant, the abnormal proportion of WDT and HPT in patients aged 60 years or above or with a course of 10 years or more were all above 45%, higher than those in other groups. The patients with larger mean amplitude of glycemic excursions (MAGE) were significantly higher than those with smaller MAGE, regardless of the abnormal proportion of WDT and HPT observed in upper limbs, lower limbs or upper and lower limbs;The results of ultrasonic measurement of nerve cross sectional area showed: the proportion of patients with ulnar nerve and median nerve abnormally thickened in the high age group (≥45 years) and the long course group (>10 years) was significantly higher than that in the low age group (<45 years) and the short course group (<10 years), the proportion of patients with larger MAGE with abnormal enlargement of median nerve was significantly higher than those with smaller MAGE. The thickening of ulnar nerve, median nerve and peroneal nerve was obvious in the patients of MAGE > 4 mmol/L. Conclusion: (1) The main nerve damage in DPN patients was thermal sensation damage, and the lower limb nerve was more vulnerable than the upper limb nerve. (2) The incidence of ulnar and median nerve damage was higher in patients aged 45 years and older or over 10 years of course. 展开更多
关键词 Quantitative thermal PERCEPTION testing Ultrasound DIABETIC PERIPHERAL NEUROPATHY Cross sectional area Mean AMPLITUDE of glycemic EXCURSIONS
MicroRNA-194 inactivates hepatic stellate cells and alleviates liver fibrosis by inhibiting AKT2 预览
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作者 Jun-Cheng Wu Rong Chen +3 位作者 Xin Luo Zheng-Hong Li Sheng-Zheng Luo Ming-Yi Xu 《世界胃肠病学杂志:英文版》 SCIE CAS 2019年第31期4468-4480,共13页
BACKGROUND Activation of hepatic stellate cells(HSCs)is a pivotal event in the onset and progression of liver fibrosis.Loss of microRNA-194(miR-194)has been reported in activated HSCs,but the actual role of miR-194 in... BACKGROUND Activation of hepatic stellate cells(HSCs)is a pivotal event in the onset and progression of liver fibrosis.Loss of microRNA-194(miR-194)has been reported in activated HSCs,but the actual role of miR-194 in liver fibrosis remains uncertain.AIM To explore the role and potential mechanism of miR-194-mediated regulation of liver fibrosis in vitro and in vivo.METHODS The expression of miR-194 was examined in human fibrotic liver tissues,activated HSCs,and a carbon tetrachloride(CCl4)mouse model by qPCR.The effects of AKT2 regulation by miR-194 on the activation and proliferation of HSCs were assessed in vitro.For in vivo experiments,we reintroduced miR-194 in mice using a miR-194 agomir to investigate the functions of miR-194 in liver fibrosis.RESULTS MiR-194 expression was notably lacking in activated HSCs from both humans and mice.Overexpression of miR-194(OV-miR-194)inhibitedα-smooth muscle actin(α-SMA)and type I collagen(Col I)expression and suppressed cell proliferation in HSCs by causing cell cycle arrest in G0/G1 phase.AKT2 was predicted to be a target of miR-194.Notably,the effects of miR-194 knockdown in HSCs were almost blocked by AKT2 deletion,indicating that miR-194 plays a role in HSCs via regulation of AKT2.Finally,miR-194 agomir treatment dramatically ameliorated liver fibrosis in CCl4-treated mice.CONCLUSION We revealed that miR-194 plays a protective role by inhibiting the activation and proliferation of HSCs via AKT2 suppression.Our results further propose miR-194 as a potential therapeutic target for liver fibrosis. 展开更多
关键词 HEPATIC stellate cells Liver FIBROSIS MicroRNA-194 AKT2
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长链非编码RNA XLOC_009038促进食管鳞癌细胞增殖、迁移和侵袭 预览 被引量:1
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作者 丁新 郑勇 +4 位作者 李静 郑雪 童娟娟 杨丹平 陈卫刚 《实用医学杂志》 CAS 北大核心 2019年第3期369-374,共6页
目的观察长链非编码RNA XLOC_009038对食管鳞状细胞癌EC109、EC9706细胞的增殖、凋亡、迁移及侵袭等生物学特性的影响并探讨其作用机制。方法构建XLOC_009038干扰质粒转染食管鳞癌EC109、EC9706细胞,使XLOC_009038基因表达下调。应用MT... 目的观察长链非编码RNA XLOC_009038对食管鳞状细胞癌EC109、EC9706细胞的增殖、凋亡、迁移及侵袭等生物学特性的影响并探讨其作用机制。方法构建XLOC_009038干扰质粒转染食管鳞癌EC109、EC9706细胞,使XLOC_009038基因表达下调。应用MTT比色法、克隆形成实验观察基因下调前后细胞增殖、克隆能力的变化;流式细胞技术检测细胞凋亡情况;Transwell测定转染前后细胞迁移及侵袭能力的变化;Western blot检测转染前后细胞内procaspase3蛋白表达量。结果两株细胞中实验组XLOC_009038基因表达明显低于对照组(P<0.001)。XLOC_009038基因表达下调后EC109、EC9706细胞的克隆、增殖能力均明显降低(P<0.05);与对照组相比实验组细胞的迁移及侵袭能力明显减弱(P<0.001);流式细胞技术显示下调XLOC_009038后EC109、EC9706两实验组细胞晚期凋亡率增高(P<0.001);Western blot显示干扰XLOC_009038后两种细胞的实验组procaspase3表达量增加(P=0.013;P<0.001)。结论XLOC_009038与食管鳞癌的发生发展密切相关,XLOC_009038过表达可能通过抑制procaspase3来调控食管鳞癌细胞的增殖、凋亡、迁移和侵袭能力。 展开更多
关键词 食管鳞癌 长链非编码RNA XLOC_009038 CASPASE3
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基于恒流充电曲线电压特征点的锂离子电池自适应容量估计方法 预览
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作者 来鑫 秦超 +1 位作者 郑岳久 韩雪冰 《汽车工程》 EI CSCD 北大核心 2019年第1期1-6,20共7页
为提高锂离子电池容量在线估计精度,本文中提出一种基于部分充电曲线特征容量在线辨识和阿伦尼乌斯容量衰减模型融合的自适应容量估计方法。针对纯电动汽车极少存在完整充电的情况,提出一种基于恒流充电电压特征点的容量在线辨识方法。... 为提高锂离子电池容量在线估计精度,本文中提出一种基于部分充电曲线特征容量在线辨识和阿伦尼乌斯容量衰减模型融合的自适应容量估计方法。针对纯电动汽车极少存在完整充电的情况,提出一种基于恒流充电电压特征点的容量在线辨识方法。该方法先利用遗传算法对缩放平移后的充电曲线进行电压特征点优化,再通过监测有关这两个不动的电压特征点的恒流充电数据,在线辨识电池的当前容量。为进一步提高容量在线估计的精度,通过增量式PID算法来融合容量在线辨识值和阿伦尼乌斯模型,进行模型参数的闭环修正。最后,交变温度寿命实验结果表明,利用本文中提出的自适应估计方法,最大估计误差不超过2%。 展开更多
关键词 容量估计 循环寿命 阿伦尼乌斯模型 模型参数 增量式PID
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Age-related Changes in the Global DNA Methylation Profile of Oligodendrocyte Progenitor Cells Derived from Rat Spinal Cords 预览
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作者 Jing ZHOU Yong-chao WU +3 位作者 Bao-jun XIAO Xiao-dong GUO Qi-xin ZHENG Bin WU 《当代医学科学(英文)》 SCIE CAS 2019年第1期67-74,共8页
Demyelination of axons plays an important role in the pathology of many spinal cord diseases and injuries.Remyelination in demyelinated lesions is primarily performed by oligodendrocyte progenitor cells(OPCs),which ge... Demyelination of axons plays an important role in the pathology of many spinal cord diseases and injuries.Remyelination in demyelinated lesions is primarily performed by oligodendrocyte progenitor cells(OPCs),which generate oligodendrocytes in the developing and mature central nervous system.The efficiency of remyelination decreases with age.Many reports suggest that this decline in remyelination results from impaired OPC recruitment and differentiation during aging.Of the various molecular mechanisms involved in aging,changes in epigenetic modifications have received particular attention.Global DNA methylation is a major epigenetic modification that plays important roles in cellular senescence and organismal aging.Thus,we aimed to evaluate the dynamic changes in the global DNA methylation profiles of OPCs derived from rat spinal cords during the aging process.We separated and cultured OPCs from the spinal cords of neonatal,4-month-old,and 16-month-old rats and investigated the age-related alterations of genomic DNA methylation levels by using quantitative colorimetric analysis.To determine the potential cause of dynamic changes in global DNA methylation,we further analyzed the activity of DNA methyltransferases(DNMTs)and the expression of DNMT1,DNMT3a,DNMT3b,TET1,TET2,TET3,MBD2,and MeCP2 in the OPCs from each group.Our results showed the genomic DNA methylation level and the activity of DNMTs from OPCs derived from rat spinal cords decreased gradually during aging,and OPCs from 16-month-old rats were characterized by global hypomethylation.During OPC aging,the mRNA and protein expression levels of DNMT3a,DNMT3b,and MeCP2 were significantly elevated;those of DNMT1 were significantly down-regulated;and no significant changes were observed in those for TET1,TET2,TET3,or MBD2.Our results indicated that global DNA hypomethylation in aged OPCs is correlated with DNMT1 downregulation.Together,these data provide important evidence for partly elucidating the mechanism of age-related impaired OPC recruitment and different 展开更多
关键词 T2 mapping DUCHENNE MUSCULAR DYSTROPHY SKELETAL muscle fat INFILTRATION
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复方中草药及其与抗生素联用对斜带石斑鱼溶藻弧菌病的治疗效果 预览
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作者 徐晓津 李秀华 +5 位作者 马一帆 李慧耀 祁欣 郑江 吕海龙 鄢庆枇 《水产学报》 CAS CSCD 北大核心 2019年第5期1338-1346,共9页
通过药物体外抑菌效果及对斜带石斑鱼抗病力影响的研究,筛选有效治疗斜带石斑鱼溶藻弧菌病复方中草药与中西药联用配方。用诃子、白芍、甘草比例分别为0.9∶1.3∶0.9、1.2∶0.9∶1.0和1∶1∶1的复方中草药对溶藻弧菌进行体外抑菌实验;... 通过药物体外抑菌效果及对斜带石斑鱼抗病力影响的研究,筛选有效治疗斜带石斑鱼溶藻弧菌病复方中草药与中西药联用配方。用诃子、白芍、甘草比例分别为0.9∶1.3∶0.9、1.2∶0.9∶1.0和1∶1∶1的复方中草药对溶藻弧菌进行体外抑菌实验;将质量分数为2.2%的复方中草药与中西药联用添加到基础饲料中设为实验组,研究中西药对斜带石斑鱼溶藻弧菌病治疗效果。复方中草药实验组Ⅰ、Ⅱ、Ⅲ为投喂饲料中添加不同比例诃子、白芍、甘草,中西药联用实验组Ⅳ、Ⅴ、Ⅵ分别为投喂饲料中添加不同比例诃子、白芍、甘草、恩诺沙星。结果显示,复方中草药配方二药物质量浓度200mg/mL,为最佳配方。40d病鱼死亡数量比较结果为对照组Ⅱ>对照组Ⅳ>对照组Ⅲ>实验组Ⅲ>实验组Ⅱ>实验组Ⅰ>实验组Ⅴ>实验组Ⅵ>实验组Ⅳ>对照组Ⅰ。实验组Ⅰ投喂饲料加诃子、白芍、甘草比例为0.9∶1.3∶0.9的复方中草药,实验组Ⅳ配方为诃子、白芍、甘草、恩诺沙星比例为0.9∶1.3∶0.9∶1.3,分别为治疗斜带石斑鱼溶藻弧菌病效果最好的复方中草药和中西药联用配方。研究表明,中西药联用复方药效强于复方中草药,均能较好治疗斜带石斑鱼溶藻弧菌病。 展开更多
关键词 斜带石斑鱼 溶藻弧菌 复方中草药 恩诺沙星
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基于蒙特卡罗技术的胶凝砂砾石坝施工定额编制研究
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作者 王兆强 陈新 +1 位作者 郑州 朱文凯 《水电能源科学》 北大核心 2019年第1期132-135,共4页
针对胶凝砂砾石坝施工尚无相关定额进行技术经济指导的现状,基于定额编制基础理论,以顺江堰胶凝砂砾石坝为例,对其施工的工、料、机消耗情况进行实时实地测定,采用标准差比较法和拉布斯准则对测定数据进行真伪检验,运用蒙特卡罗模拟技... 针对胶凝砂砾石坝施工尚无相关定额进行技术经济指导的现状,基于定额编制基础理论,以顺江堰胶凝砂砾石坝为例,对其施工的工、料、机消耗情况进行实时实地测定,采用标准差比较法和拉布斯准则对测定数据进行真伪检验,运用蒙特卡罗模拟技术对检验处理后的数据进行仿真模拟,整理分析模拟数据,完成依托工程的定额编制,改善了胶凝砂砾石坝在推广初期由于典型工程和样本数据太少导致的统计结果精度不高的问题,为胶凝砂砾石坝施工定额正式编制提供理论和数据支持,也为企业同类项目技术经济分析提供参考。 展开更多
关键词 胶凝砂砾石坝 定额编制 蒙特卡罗技术 施工
一株桃树内生真菌Pestalotiopsis vismiae N1培养条件优化与抗氧化、抗菌活性分析
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作者 侯若琳 刘鑫 +4 位作者 王丹亭 陈磊 林文雄 郑明锋 傅俊生 《应用与环境生物学报》 CAS CSCD 北大核心 2019年第2期385-391,共7页
对一株内生真菌韦司梅拟盘多毛孢(Pestalotiopsis vismiae)的培养条件进行探究,在此基础上进一步对其发酵提取物抗氧化、抗菌活性进行分析.通过测定菌丝的生长速度寻找菌丝培养适宜的温度、碳源、氮源和pH,并采用正交试验优化培养条件;... 对一株内生真菌韦司梅拟盘多毛孢(Pestalotiopsis vismiae)的培养条件进行探究,在此基础上进一步对其发酵提取物抗氧化、抗菌活性进行分析.通过测定菌丝的生长速度寻找菌丝培养适宜的温度、碳源、氮源和pH,并采用正交试验优化培养条件;通过测定菌株深层发酵液提取物对羟基和DPPH自由基的清除率以分析其抗氧化活性;通过测定菌株深层发酵液提取物对多种病原细菌抑菌圈大小的影响来分析其抗菌活性.结果表明,韦司梅拟盘多毛孢菌丝最适宜培养温度为25 ℃,在该温度培养条件下菌丝生长最佳碳源为蔗糖,最佳氮源为酵母提取粉,最佳初始pH为6.5,这3种因素的显著性差异大小顺序为碳源>氮源> pH;菌株深层发酵液提取物具有良好的抗氧化活性,其对羟基自由基和DPPH自由基清除率的EC50分别为1.19 mg/mL和0.56 mg/mL;菌株发酵液提取物对铜绿假单胞杆菌、金黄色葡萄球菌均具有一定的抑制作用;深层发酵液提取物抗氧化和抗菌活性具有一定的稳定性.本研究结果可为深入开发利用该真菌资源提供科学依据. 展开更多
关键词 韦司梅拟盘多毛孢 生长培养 抗氧化活性 抗菌活性
广西部分地区猪链球菌血清型及其毒力因子流行性调查分析 预览
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作者 石大丽 葛晨玲 +7 位作者 朱远致 辛佳亮 葛强 袁敬知 王晓晔 李珣 郑敏 韦显凯 《中国畜牧兽医》 CAS 北大核心 2019年第4期1116-1126,共11页
为探究广西部分地区猪链球菌(Streptococcus suis,SS)流行菌株主要血清型及毒力因子分布情况。本试验于2018年1月至2018年6月对从多个猪场采集到的116份疑似链球菌感染的组织病料(脑、肺脏、淋巴结等)进行病原菌检测,采用细菌分离鉴定... 为探究广西部分地区猪链球菌(Streptococcus suis,SS)流行菌株主要血清型及毒力因子分布情况。本试验于2018年1月至2018年6月对从多个猪场采集到的116份疑似链球菌感染的组织病料(脑、肺脏、淋巴结等)进行病原菌检测,采用细菌分离鉴定、形态学观察及PCR扩增等方法对病原菌及其血清型和部分毒力因子进行鉴定。结果显示,116份样品共分离到链球菌32株,阳性率为27.59%(32/116),其血清型主要以SS2和SS9为主,分离率分别为40.63%(13/32)和43.75%(14/32),其他血清型为15.63%(5/32);毒力因子检测结果表明:SLY、MRP、EPF以及SBP2′因子的检出率分别为:81.25%(26/32)、59.38%(19/32)、50.00%(16/32)和71.88%(23/32)。32株链球菌中以SLY^+MRP^+EPF^+SBP2^′+(13株)、SLY^+MRP^-EPF^-SBP2′^-(5株)、SLY^+MRP^+EPF^-SBP2′^+(5株)为主要的毒力基因型,其中SS2均能检测出3个或3个以上的毒力因子。玉林、柳州市主要分布SS9型,南宁、百色市主要分布SS2型;广西不同地区毒力因子的分布情况存在差异且不同血清型或同一血清型的链球菌毒力因子的分布情况也各不相同,其中SS2携带的毒力因子检出率明显高于其他血清型。该研究可为今后猪链球菌疫苗及致病机理研究提供理论依据,为广西地区猪场链球菌血清型疫苗选择提供指导。 展开更多
关键词 猪链球菌 血清型 毒力基因 防控
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中线法尾矿砂的邓肯-张模型参数试验研究 预览
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作者 黄鑫 蔡晓光 +1 位作者 郑志华 李思汉 《防灾科技学院学报》 2019年第2期29-35,共7页
中线法筑坝工艺目前在国内大型尾矿库工程中已逐步推广使用。选取云南某中线法铜矿尾矿库的两种尾矿砂:底流尾矿砂和溢流尾矿砂,按设计干密度要求制备饱和重塑样,通过三轴固结排水(CD)剪切试验,得到了两种尾矿砂的邓肯-张E-μ模型和E-B... 中线法筑坝工艺目前在国内大型尾矿库工程中已逐步推广使用。选取云南某中线法铜矿尾矿库的两种尾矿砂:底流尾矿砂和溢流尾矿砂,按设计干密度要求制备饱和重塑样,通过三轴固结排水(CD)剪切试验,得到了两种尾矿砂的邓肯-张E-μ模型和E-B模型的10个试验参数,并分析了两种模型的区别。试验结果可为后期数值计算分析提供参数依据。 展开更多
关键词 尾矿砂 E-μ模型 E-B模型 三轴试验
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