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即刻耳甲电针刺激对轻度认知障碍脑功能影像的影响初探
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作者 郭春蕾 马跃 +3 位作者 高山山 罗屹 陈庆燕 方继良 《阿尔茨海默病及相关病杂志》 2024年第2期94-102,81,共10页
目的:基于静息态功能磁共振成像(rs-fMRI)探讨即刻(30分钟)耳甲电针(taVNS)刺激对轻度认知障碍(MCI)患者脑功能的影响。方法:纳入22例MCI患者,随机分为taVNS组和sham taVNS组,每组各11例,同时纳入11例健康对照(HCs)。3组受试者均进行30... 目的:基于静息态功能磁共振成像(rs-fMRI)探讨即刻(30分钟)耳甲电针(taVNS)刺激对轻度认知障碍(MCI)患者脑功能的影响。方法:纳入22例MCI患者,随机分为taVNS组和sham taVNS组,每组各11例,同时纳入11例健康对照(HCs)。3组受试者均进行30分钟耳部电针刺激,其中taVNS组和HCs组接受耳甲刺激位于迷走神经主要分布区,sham taVNS组接受的刺激位于非迷走神经分布的耳舟部,在刺激前后各进行一次rs-fMRI扫描。采用DPABI 8.0软件对rs-fMRI扫描结果进行预处理,随后计算功能连接(FC),对3组受试者刺激前后的FC图像进行比较,并将结果提值,用Graphpad Prism9.0.0进行事后分析,观察taVNS对脑功能的影响。结果:与刺激前相比,刺激后taVNS组右侧海马与右侧小脑_6的FC值显著降低(P<0.005)、左侧尾状核与右侧额上回以及右侧苍白球与左侧尾状核的FC值显著升高(P<0.05);刺激后HCs组左侧尾状核与小脑_8的FC值显著降低(P<0.05)。结论:即刻taVNS可以调节记忆及认知脑区,以及基底节区及小脑等脑功能网络,可能是taVNS治疗MCI的效应靶点。 展开更多
关键词 轻度认知障碍 耳甲电针 静息态功能磁共振成像 功能连接
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Parboiled rice supplementation alleviates high-fat diet-induced hyperlipidemia by regulating genes and gut microbiota in mice
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作者 Xiuxiu Wu Tianyi Guo +7 位作者 Biao Li Shuai Han Zuomin Hu yi luo Dandan Qin Yaping Zhou Feijun luo Qinlu Lin 《Food Science and Human Wellness》 SCIE CSCD 2024年第3期1422-1438,共17页
Dietary parboiled rice(PR)has a low risk of disease,but little is known about the contribution of PR to the prevention of hyperlipidemia.The potential role and underlying mechanisms of PR in hyperlipidemia were evalua... Dietary parboiled rice(PR)has a low risk of disease,but little is known about the contribution of PR to the prevention of hyperlipidemia.The potential role and underlying mechanisms of PR in hyperlipidemia were evaluated in this study.Male C57BL/6J mice were fed with a normal diet,high-fat diet(HFD)containing refined rice(HFDRR)or PR(HFDPR).It was found that PR intervention improved lipid accumulation in mice.Transcriptomic data analysis revealed that 27 genes were up-regulated(mostly involved in lipid breakdown)and 86 genes were down-regulated(mostly involved in inflammatory responses)in the HFDPR group compared to the HFDRR group.And 15 differentially expressed genes(DEGs)were validated by quantitative real-time PCR(RT-qPCR),while protein interaction network showed that protein tyrosine phosphatase receptor type C(PTPRC)has a central role.The gut microbiota of mice was also altered after different dietary treatments,with higher ratio of Firmicutes and Bacteroidetes,increased abundances of Ruminococcaceae,Lachnospiraceae,Christensenellaceae,Porphyromonadaceae,Rikenellaceae and Prevotellaceae,and decreased abundances of Lactobacillaceae,Peptostreptococcaceae,Erysipelotrichaceae and Actinobacteria in the HFDRR group.In addition,it was observed that PPAR signaling pathway may act as a bridge between DEGs and differential gut microbiota.These results suggested that PR can prevent hyperlipidemia by modulating liver genes and gut microbiota. 展开更多
关键词 Parboiled rice Blood lipids TRANSCRIPTOME Gut microbiota PPAR Signaling pathway
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SYNTHESIS AND ANTITUMOR ACTIVITY OF PEPTIDYL-N^2-HYDROXYMETHYL-5-FLUOROURACIL
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作者 yi luo Ren Xi ZHUO Chang Lie FAN Department of Chemistry, Wuhan University, Wuhan 430072 《Chinese Chemical Letters》 SCIE CAS CSCD 1993年第7期581-582,共2页
Six hydrophobic peptidyl and four amino acid (L-Val, L-Leu,L-Phe, L-Gly) derivatives of 5-fluorouracil(5-FU) were synthesized.The structure of these compounds were characterized by ~1H-NMR, IR,UV spectra and elemental... Six hydrophobic peptidyl and four amino acid (L-Val, L-Leu,L-Phe, L-Gly) derivatives of 5-fluorouracil(5-FU) were synthesized.The structure of these compounds were characterized by ~1H-NMR, IR,UV spectra and elemental analysis. The antitumor activity was test-ed against EAC cells in vitro. 展开更多
关键词 peptidyl ANTITUMOR HYDROPHOBIC WEBER linkage MARKED residue
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Dissecting the underlying pharmaceutical mechanism of Danggui Buxue decoction acting on idiopathic pulmonary fibrosis with network pharmacology
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作者 Cai-Ping Zhao Hang Li +5 位作者 Xiao-Hong Liu Shuang Liang Xue-Lei Liu Xin-Rong Li yi luo Mei-Ling Zhu 《Traditional Medicine Research》 2020年第4期238-251,共14页
Backgroud:Danggui Buxue decoction(DBD),a classical prescription in traditional Chinese medicine,has been found to have protective effect on bleomycin-induced pulmonary fibrosis in rats by reducing alveolar inflammatio... Backgroud:Danggui Buxue decoction(DBD),a classical prescription in traditional Chinese medicine,has been found to have protective effect on bleomycin-induced pulmonary fibrosis in rats by reducing alveolar inflammation and fibrosis.However,the biological activity of individual chemical components and mechanism of action of whole formula are not clear.Methods:Potential targets of active ingredients of DBD were collected through Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform and SymMap database.Target genes related to idiopathic pulmonary fibrosis were obtained from the Online Mendelian Inheritance in Man database,Therapeutic Targets Database and Gkb database.Then,the common targets were obtained by overlapping the potential targets of active ingredients in DBD and diseases related targets.The selected targets were subjected to Kyoto Encyclopedia of Genes and Genomes signaling pathway and Gene Ontology analysis,and the network map of active component-target-pathway was established using Cytoscape 3.7.1 software.The active components of DBD with most targets were selected for fibrosis-related marker verification.The mRNA and protein expression of fibrosis markers,α-smooth muscle actin,collagen 1 and fibronectin,were detected in TGF-β1-induced fibroblast cell line after treatment with the active components.Results:The 14 active ingredients,such as quercetin and kaempferol,were screened from DBD.It acts on 26 targets like estrogen receptor 2 and prostaglandin-endoperoxide synthase 2,and mainly involves 38 signaling pathways such as cell inflammation and autophagy.Kaempferol and quercetin are the two compounds with the highest network regulation,which can inhibit the transformation of fibroblasts into myofibroblasts and reduce the expression of fibrosis markersα-smooth muscle actin,collagen 1 and fibronectin.Conclusion:The integration mode of multi-component,multi-target,multi-channel and mechanism of DBD in the treatment of idiopathic pulmonary fibrosis are predicted by means of network pharmacology.Our study could indicate the direction of further anti-fibrotic mechanism research. 展开更多
关键词 Danggui Buxue decoction Pulmonary fibrosis Network pharmacology MYOFIBROBLAST Chinese medicine formula Mechanism of action
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Study on the Specific GC Chromatograms of Volatile Oil from Xinyi Biyan Pills
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作者 Huiduan LONG yi luo Wei WEI 《Agricultural Biotechnology》 CAS 2021年第3期105-108,129,共5页
[Objectives]This study was conducted to establish characteristic chromatograms of of the volatile oil of Xinyi Biyan Pills by gas chromatography,discover possible problems in the production processes of different manu... [Objectives]This study was conducted to establish characteristic chromatograms of of the volatile oil of Xinyi Biyan Pills by gas chromatography,discover possible problems in the production processes of different manufacturers,and further improve the quality control methods.[Methods]The volatile oil in samples was extracted and tested by gas chromatography to collect chromatograms,which were analyze and evaluated by the similarity evaluation software of chromatographic fingerprints of traditional Chinese medicine.[Results]Nineteen common peaks were calibrated in the characteristic chromatograms;and the characteristic chromatograms of samples produced by different manufacturers were obviously different.[Conclusions]Controlling the volatile components in Xinyi Biyan Pills by the established characteristic chromatograms of GC is accurate and feasible,and can be used as a quality control method for Xinyi Biyan Pills. 展开更多
关键词 Xinyi Biyan Pills Volatile oil Gas chromatography Characteristic chromatogram
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提高大学生专业认同感研究及其对国内大学的启示——以西弗吉尼亚大学(WVU)Mining Engineering为例 被引量:2
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作者 李忠辉 王恩元 +5 位作者 赵恩来 刘晓斐 王亮 程健维 yi luo Hua Jiang 《高教学刊》 2019年第12期9-10,14,共3页
学生对所学专业的认同感是决定其专业热爱程度、学习积极性的重要影响因素。文章分析了国内矿业、安全类专业学生在专业认同感方面存在问题。阐述了国外高校在矿业工程学生专业认同感建立及培养方面的经验,提出了我国在"双一流&qu... 学生对所学专业的认同感是决定其专业热爱程度、学习积极性的重要影响因素。文章分析了国内矿业、安全类专业学生在专业认同感方面存在问题。阐述了国外高校在矿业工程学生专业认同感建立及培养方面的经验,提出了我国在"双一流"背景下培养采矿、安全类专业学生专业认同感的对策。 展开更多
关键词 专业认同感 矿业工程 安全工程 大学生
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掌心里的天机——从旋光、特异性识别到手性污染
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作者 刘麒麟 吴仪 +2 位作者 罗毅 刘媛 吴凯群 《大学化学》 CAS 2023年第4期88-97,共10页
生活中许多重要的化学物质均具有手性,但大众对其认识不足。本文详细介绍了三个科普实验:手性万花筒、简易旋光仪和手性指示剂。手性万花筒可简单鉴别手性物质与非手性物质;简易旋光仪可直观地区分手性物质是左旋还是右旋,并检测手性物... 生活中许多重要的化学物质均具有手性,但大众对其认识不足。本文详细介绍了三个科普实验:手性万花筒、简易旋光仪和手性指示剂。手性万花筒可简单鉴别手性物质与非手性物质;简易旋光仪可直观地区分手性物质是左旋还是右旋,并检测手性物质的旋光度;手性指示剂无需仪器,通过颜色变化就可分辨特定结构的对映体,适合向更专业的人群展示手性物质的特异性识别。这三个实验深入浅出,操作简单,现象生动有趣,向大众科普了手性化学物质的物理性质和化学性质,有良好的科普实践展示效果,多方位展示了手性之美、化学之美。 展开更多
关键词 万花筒 简易旋光仪 手性识别 教学实验 梯度科普
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Metformin accelerates bone fracture healing by promoting type H vessel formation through inhibition of YAP1/TAZ expression 被引量:1
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作者 Zhe Ruan Hao yin +26 位作者 Teng-Fei Wan Zhi-Rou Lin Shu-Shan Zhao Hai-Tao Long Cheng Long Zhao-Hui Li Yu-Qi Liu Hao luo Liang Cheng Can Chen Min Zeng Zhang-Yuan Lin Rui-Bo Zhao Chun-Yuan Chen Zhen-Xing Wang Zheng-Zhao Liu Jia Cao yi-yi Wang Ling Jin yi-Wei Liu Guo-Qiang Zhu Jing-Tao Zou Jiang-Shan Gong yi luo yin Hu Yong Zhu Hui Xie 《Bone Research》 SCIE CAS CSCD 2023年第3期625-637,共13页
Due to increasing morbidity worldwide,fractures are becoming an emerging public health concern.This study aimed to investigate the effect of metformin on the healing of osteoporotic as well as normal fractures.Type H ... Due to increasing morbidity worldwide,fractures are becoming an emerging public health concern.This study aimed to investigate the effect of metformin on the healing of osteoporotic as well as normal fractures.Type H vessels have recently been identified as a bone-specific vascular subtype that supports osteogenesis.Here,we show that metformin accelerated fracture healing in both osteoporotic and normal mice.Moreover,metformin promoted angiogenesis in vitro under hypoxia as well as type H vessel formation throughout fracture healing.Mechanistically,metformin increased the expression of HIF-1α,an important positive regulator of type H vessel formation,by inhibiting the expression of YAP1/TAZ in calluses and hypoxia-cultured human microvascular endothelial cells(HMECs).The results of HIF-1αor YAP1/TAZ interference in hypoxia-cultured HMECs using si RNA further suggested that the enhancement of HIF-1αand its target genes by metformin is primarily through YAP1/TAZ inhibition.Finally,overexpression of YAP1/TAZ partially counteracted the effect of metformin in promoting type H vessel-induced angiogenesis-osteogenesis coupling during fracture repair.In summary,our findings suggest that metformin has the potential to be a therapeutic agent for fractures by promoting type H vessel formation through YAP1/TAZ inhibition. 展开更多
关键词 YAP1 HEALING FRACTURE
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Equation governing the probability density evolution of multi-dimensional linear fractional differential systems subject to Gaussian white noise
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作者 yi luo Meng-Ze Lyu +1 位作者 Jian-Bing Chen Pol D.Spanos 《Theoretical & Applied Mechanics Letters》 CAS CSCD 2023年第3期199-208,共10页
Stochastic fractional differential systems are important and useful in the mathematics,physics,and engineering fields.However,the determination of their probabilistic responses is difficult due to their non-Markovian ... Stochastic fractional differential systems are important and useful in the mathematics,physics,and engineering fields.However,the determination of their probabilistic responses is difficult due to their non-Markovian property.The recently developed globally-evolving-based generalized density evolution equation(GE-GDEE),which is a unified partial differential equation(PDE)governing the transient probability density function(PDF)of a generic path-continuous process,including non-Markovian ones,provides a feasible tool to solve this problem.In the paper,the GE-GDEE for multi-dimensional linear fractional differential systems subject to Gaussian white noise is established.In particular,it is proved that in the GE-GDEE corresponding to the state-quantities of interest,the intrinsic drift coefficient is a time-varying linear function,and can be analytically determined.In this sense,an alternative low-dimensional equivalent linear integer-order differential system with exact closed-form coefficients for the original highdimensional linear fractional differential system can be constructed such that their transient PDFs are identical.Specifically,for a multi-dimensional linear fractional differential system,if only one or two quantities are of interest,GE-GDEE is only in one or two dimensions,and the surrogate system would be a one-or two-dimensional linear integer-order system.Several examples are studied to assess the merit of the proposed method.Though presently the closed-form intrinsic drift coefficient is only available for linear stochastic fractional differential systems,the findings in the present paper provide a remarkable demonstration on the existence and eligibility of GE-GDEE for the case that the original high-dimensional system itself is non-Markovian,and provide insights for the physical-mechanism-informed determination of intrinsic drift and diffusion coefficients of GE-GDEE of more generic complex nonlinear systems. 展开更多
关键词 Globally-evolving-based generalized density evolution equation(GE-GDEE) Linear fractional differential system Non-Markovian system Analytical intrinsic drift coefficient Dimension reduction
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An image mosaic technique with non-overlapping regions based on microscopic vision in precision assembly
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作者 Yawei Li Xiaodong Wang +1 位作者 Tao Wang yi luo 《Nanotechnology and Precision Engineering》 EI CAS CSCD 2023年第4期66-74,共9页
Microscopic vision has been widely applied in precision assembly.To achieve sufficiently high resolution in measurements for precision assembly when the sizes of the parts involved exceed the field of view of the visi... Microscopic vision has been widely applied in precision assembly.To achieve sufficiently high resolution in measurements for precision assembly when the sizes of the parts involved exceed the field of view of the vision system,an image mosaic technique must be used.In this paper,a method for constructing an image mosaic with non-overlapping areas with enhanced efficiency is proposed.First,an image mosaic model for the part is created using a geometric model of the measurement system installed on a X-Y-Z precision stages with high repeatability,and a path for image acquisition is established.Second,images are captured along the same path for a specified calibration plate,and an entire image is formed based on the given model.The measurement results obtained from the specified calibration plate are utilized to identify mosaic errors and apply compensation for the part requiring measurement.Experimental results show that the maximum error is less than 4μm for a camera with pixel equivalent 2.46μm,thereby demonstrating the accuracy of the proposed method.This image mosaic technique with non-overlapping regions can simplify image acquisition and reduce the workload involved in constructing an image mosaic. 展开更多
关键词 Image mosaic Microscopic vision Visual measurement Precision assembly
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基于Hilbert变换的全波场分离逆时偏移成像 被引量:14
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作者 王一博 郑忆康 +3 位作者 薛清峰 常旭 Tong W.Fei yi luo 《地球物理学报》 SCIE EI CAS CSCD 北大核心 2016年第11期4200-4211,共12页
逆时偏移方法利用双程波算子模拟波场的正向和反向传播,通常采用互相关成像条件获得偏移剖面,是一种高精度的成像方法.但是传统的互相关成像条件会在偏移结果中产生低频噪声;此外,如果偏移速度中存在剧烈速度变化还可能进一步产生偏移假... 逆时偏移方法利用双程波算子模拟波场的正向和反向传播,通常采用互相关成像条件获得偏移剖面,是一种高精度的成像方法.但是传统的互相关成像条件会在偏移结果中产生低频噪声;此外,如果偏移速度中存在剧烈速度变化还可能进一步产生偏移假象.为了提高逆时偏移的成像质量,可在成像过程中先对震源波场和检波点波场分别进行波场分离,然后选择合适的波场成分进行互相关成像.本文基于Hilbert变换,推导了可在偏移过程中进行上下行和左右行波场分离的高效波场分离公式以及相应的成像条件,结合Sigsbee 2B合成数据,给出了不同波场成分的互相关成像结果.数值算例结果表明,采用本文提出的高效波场分离算法以及合理的波场成分互相关成像条件可以获得高信噪比的成像结果. 展开更多
关键词 逆时偏移 互相关成像条件 波场分离 HILBERT变换
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对称矩阵行压缩的下标变换定理及在测绘中的应用 被引量:2
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作者 刘正才 陈正阳 +4 位作者 朱建军 肖本林 易重海 王怀玉 yi luo 《湖南大学学报(自然科学版)》 EI CAS CSCD 北大核心 2009年第6期76-82,共7页
证明了整数环误差引理,进一步证明了对称阵行压缩的下标逆变换公式,这将其解压缩算法的时间复杂度从O(n2)降低到O(1).分析了对称阵的行压缩方式下的2种解压缩算法的相对运行效率,分析表明,当采用下标逆变换算法从压缩的对称矩阵中查询... 证明了整数环误差引理,进一步证明了对称阵行压缩的下标逆变换公式,这将其解压缩算法的时间复杂度从O(n2)降低到O(1).分析了对称阵的行压缩方式下的2种解压缩算法的相对运行效率,分析表明,当采用下标逆变换算法从压缩的对称矩阵中查询元素时,其查询效率比二重循环算法高得多.将这些公式和算法用来管理测绘工作中的大规模对称矩阵,如ITRF2000-ALASKA站群的协方差矩阵,既可进一步节约计算机存储空间和网络资源,还可提高其数据查询效率. 展开更多
关键词 压缩 下标变换 下标逆变换 整数环误差引理 ITRF 相对运行效率
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Bladder Malignant Granular Cell Tumor with EP300 Gene Mutation: A Case Report and Literature Review
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作者 Di Zhu Xinle Ren +2 位作者 yi luo Bing Huang Jian Huang 《Journal of Cancer Therapy》 2021年第5期240-253,共14页
<strong>Background</strong><span style="font-family:Verdana;"><strong>:</strong></span><b><span style="font-family:""> </span></b>&l... <strong>Background</strong><span style="font-family:Verdana;"><strong>:</strong></span><b><span style="font-family:""> </span></b><span style="font-family:""><span style="font-family:Verdana;">Malignant granular cell tumor (GCT) is extremely rare. Malignant GCT with EP300 gene mutation in the bladder has not been reported in the literature. </span><b><span style="font-family:Verdana;">Case Presentation</span></b></span><b><span style="font-family:Verdana;">:</span></b><span style="font-family:""><span style="font-family:Verdana;"> We report a special case of 45-year-old female with malignant GCT of the bladder. Pathological examination showed that the mass was 11 × 11 × 4.5 cm in size, involved in the bladder’s posterior wall. Under the microscope, the tumor cells were arranged in the shape of a nest or cord to infiltrate the bladder’s wall. The tumor cells were pleomorphic, red-stained granular within the cytoplasm, with increased nuclear/cyto</span><span style="font-family:Verdana;">plasmic ratio, vacuolar nuclei, and obvious nucleoli. The tumor cells were</span> <span style="font-family:Verdana;">showed obvious nuclear atypia, and the mitosis was more than 5/50HPF. </span><span style="font-family:Verdana;">Coagulative necrosis was widely showed within the tumor. Immunohistochemi</span><span><span style="font-family:Verdana;">stry (IHC) showed that S-100, NSE, CD68, CR, </span><i><span style="font-family:Verdana;">α</span></i><span style="font-family:Verdana;">-AT, and TFE-3 were</span></span><span style="font-family:Verdana;"> strongly </span><span style="font-family:Verdana;">positive, and the Ki-67 proliferation index was around 15%. The</span><span style="font-family:Verdana;"> next-genera</span><span style="font-family:Verdana;">tion high throughput sequencing indicated that EP300 gene was missense</span><span style="font-family:Verdana;"> mutated (c.457A > G) with 33% mutation abundance, and genes of DPYD (c.1627A > G), ERCC1 (c.354T > C), NQO1 (c.559C > T), TPMT (c.719A > G) and XRCC1 (c.1196A > G) were polymorphic mutated. The patient died after three months of the second surgical treatment. </span><b><span style="font-family:Verdana;">Conclusions</span></b></span><b><span style="font-family:Verdana;">:</span></b><b><span style="font-family:""> </span></b><span style="font-family:Verdana;">We report for the first time a primary bladder malignant GCM accompanied by mutations in special driving genes such as EP300. We also conducted a comprehensive literature review and an in-depth discussion.</span> 展开更多
关键词 Malignant Granular Cell Tumor BLADDER HISTOPATHOLOGY EP300 Next-Generation High Throughput Sequencing
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Excess Coalbed Methane Production Mechanism in the Process of Coal Tectonic Deformation
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作者 yi luo Shuying Li 《Journal of Geoscience and Environment Protection》 2016年第7期175-178,共4页
Source and occurrence of Excess Coalbed Methane is a long-term concern research topic in Coal Geology and Structural Geology. Since it is essential to understand the outburst mechanism of coal gas, and to support the ... Source and occurrence of Excess Coalbed Methane is a long-term concern research topic in Coal Geology and Structural Geology. Since it is essential to understand the outburst mechanism of coal gas, and to support the coalbed methane development projects as the theoretical basis. We found in the study that, huge imparity is behind the evolutionary trend on molecular structure and the mechanism of influence from different deformation. The thesis demonstrates its probable routes of gas evolution according to distinct deformation mechanisms of coal. In the role of brittle deformation mechanism, a rapidly formed advantage rupture surface along with sliding motion from which has worked on coal. As another result, mechanical energy has transformed into friction and kinetic energy during the process. Kinetic energy increases simultaneously, which brings some results, that the new generated gas molecule. While the chemical structure of coal remains in a steady-state and do not react easily an outburst with gas. Mechanical energy turns into strain energy through its ductile deformation mechanism. The dislocation or lamellar slip made disordered between the constitutional units of aromatic rings and aromatic lamellas, as soon as secondary structural defects created. On another hand, molecular motion accelerates and splits off the small molecular on the side chain, due to the dissociation of aromatic nucleus;CH<sub>4  </sub>gas molecular was generated and placed in the secondary structural defect of coal, along with a great deal of strain energy in non-steady-state. By breaking away the balance maintaining terms, huge strain energy releases suddenly, small moleculars are free from the secondary structure defect, react outburst with gas. Furthermore to extend the discussion of the conventional physical ideas on coal absorb gas, according to the phenomenon of exceeded CBM, the gas molecular has a significant chance existing in a low bond energy of chemical bonds of coal structure. 展开更多
关键词 Tectonic Coal Gas Generation by Deformation Mechanism of Gas Generation
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层剥离MWW结构分子筛的直接可控合成 被引量:7
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作者 王振东 Magdalena OCichock +4 位作者 罗翼 张斌 孙洪敏 唐颐 杨为民 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2020年第7期1062-1066,共5页
分子筛是一类重要的催化材料,在石油和煤制化学品工业中应用广泛.目前,国际分子筛协会结构委员会确认的248种分子筛骨架结构中的19种已经商业化应用,如FAU,MFI,*BEA,MOR和MWW.具有多层结构的MCM-22是MWW结构分子筛的典型代表,已应用于... 分子筛是一类重要的催化材料,在石油和煤制化学品工业中应用广泛.目前,国际分子筛协会结构委员会确认的248种分子筛骨架结构中的19种已经商业化应用,如FAU,MFI,*BEA,MOR和MWW.具有多层结构的MCM-22是MWW结构分子筛的典型代表,已应用于苯与乙烯液相烷基化制乙苯.然而,烷基化反应主要发生在位于MCM-22分子筛晶体外表面的半超笼内,位于10元环孔道和12元环超笼内的酸性位对乙烯转化率几乎没有贡献.因此,有必要制备能够容纳更多半超笼的具有超大外比表面积的新型MWW结构分子筛.厚度仅2.5 nm的单层MWW结构分子筛ITQ-2具备以上特征,但是其较弱的酸性质及复杂的制备过程使其无法工业应用.受到采用具有长碳链的双子季铵阳离子两亲性有机结构导向剂直接合成层状MFI分子筛的启发,其有机结构导向剂同时起到导向MFI结构和抑制晶体沿b轴方向生长的作用.类似地,层剥离MWW结构分子筛也被直接合成出来,但所得材料的催化性能不理想,且有机结构导向剂不易得.通过对MCM-22分子筛的结构分析发现,其合成态是由多个MWW结构层有序组装而成,可以通过溶胀处理增大层间距,削弱层间相互作用,经超声处理即可实现层剥离.鉴于此,本文采用向合成MCM-22分子筛的常规体系中加入二环己基胺充当有机添加剂构筑'双功能'合成体系的策略,开展层剥离MWW结构分子筛新材料的直接合成.X射线衍射(XRD)结果表明,与MCM-22分子筛相比,在二环己基胺参与下合成的分子筛SCM-1(DCHA/SiO2=0.4)和SCM-6(DCHA/SiO2=0.6)的XRD谱中与MWW结构c轴方向有关的(101)和(102)晶面的衍射峰出现偏移和重叠的现象,表明其沿c轴方向有序性降低.扫描电子显微镜显示,所有样品均为片状形貌,其中SCM-6含有少量无定形物种.氩气及氮气物理吸附结果表明,SCM-1和SCM-6具有超大外比表面积,而微孔体积小于MCM-22分子筛.透射电子显微镜表征结果表明,MCM-22为多层结构,厚度约为20 nm,而SCM-1和SCM-6的厚度分别约为5.0和2.5 nm,对应双层和单层结构,表明在有机添加剂参与下直接合成了层剥离的新型MWW结构分子筛.值得注意的是,通过调节添加剂用量,可以调节剥离程度,即实现可控层剥离,得到完全(单层)或部分(双层)剥离的MWW结构分子筛.该方法所采用的添加剂的尺寸是关键因素,选用尺寸大于有机结构导向剂的添加剂才能有效抑制晶体沿c轴方向的有序生长,实现层剥离MWW结构分子筛的直接合成.采用该方法合成的新型MWW结构分子筛具有超大外比表面积和更多的表面半超笼,在苯与乙烯液相烷基化反应中,SCM-1催化的乙烯转化率明显高于MCM-22分子筛.SCM-6因结晶度低而未能表现出优势.进一步比较SCM-1和MCM-22的催化稳定性发现,SCM-1的稳定性更好,经过64 h连续反应,其吸附的有机物及积碳更少.在1,3,5-三异丙苯裂解反应中,SCM-1的催化性能也明显优于MCM-22. 展开更多
关键词 分子筛 MWW 烷基化 乙苯 剥离 催化
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青龙矿田兰旗组火山岩岩石学、地球化学特征及成因探讨
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作者 李国臣 孙祥 +1 位作者 罗毅 谷勇 《自然科学》 2015年第2期40-48,共9页
青龙铀矿田中侏罗统兰旗组为一套较厚中性火山熔岩–火山碎屑岩,是含矿层上覆最重要保护层。基于火山岩相学特征将兰旗组划分为3段:下段安山集块岩、安山角砾岩、及碎斑安山岩、安山岩;中段紫红色凝灰质砂岩、砾岩;上段气孔状安山岩夹... 青龙铀矿田中侏罗统兰旗组为一套较厚中性火山熔岩–火山碎屑岩,是含矿层上覆最重要保护层。基于火山岩相学特征将兰旗组划分为3段:下段安山集块岩、安山角砾岩、及碎斑安山岩、安山岩;中段紫红色凝灰质砂岩、砾岩;上段气孔状安山岩夹薄层黑云母晶屑凝灰岩。对各层位的火山熔岩进行了岩石地球化学分析,结果显示总体具有低镁低钛高铝高钾特征,属准铝质系列和高钾钙碱性系列;稀土元素、相容元素、不相容元素等显示下地壳岩浆混入幔源特征,并显示了各阶段混染程度存在强–弱–强演化趋势;岩浆成因并非大规模结晶分异,可能主要为部分熔融;其形成构造背景为板内造山环境,处于地壳缩短加厚晚期向减薄转换阶段。 展开更多
关键词 兰旗组 中性火山岩 岩石学 地球化学 成因
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Pentacam眼前节分析仪诊断早期圆锥角膜的临床应用 被引量:4
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作者 罗毅 侯晓燕 黎作为 《国际眼科杂志》 CAS 北大核心 2020年第9期1603-1606,共4页
目的:探讨Pentacam眼前节分析仪在早期圆锥角膜诊断中的临床应用。方法:选取2019-02/12于我院就诊的早期圆锥角膜患者49例49眼纳入研究,参照Rabinowitz诊断标准,将其分为临床期圆锥角膜组27例27眼和亚临床期圆锥角膜组22例22眼,另选取20... 目的:探讨Pentacam眼前节分析仪在早期圆锥角膜诊断中的临床应用。方法:选取2019-02/12于我院就诊的早期圆锥角膜患者49例49眼纳入研究,参照Rabinowitz诊断标准,将其分为临床期圆锥角膜组27例27眼和亚临床期圆锥角膜组22例22眼,另选取20例20眼有近视、散光史的正常眼作为对照组。采用Pentacam眼前节分析仪分别测定3组受检者角膜表面变异指数(ISV)、圆锥角膜指数(KI)、垂直不对称指数(IVA)、中央圆锥角膜指数(CKI)、高度离心指数(IHD)、高度不对称性指数(IHA)、不规则指数(ABR)、最小曲率半径(Rmin)、角膜散光(CYL)、角膜前表面高度(AE)、角膜前表面最大屈光力(Kmax)、角膜后表面高度(PE)变化,比较三组受检者各指标检测值,绘制ROC曲线,分析各指标诊断圆锥角膜的临床价值。结果:三组受检者ISV、KI、IVA、CKI、IHD、IHA、ABR、Rmin、CYL、AE、Kmax、PE检测值比较有差异(P<0.05);临床期圆锥角膜组受检者ISV、KI、IVA、CKI、IHD、IHA、ABR、Rmin、CYL、AE、Kmax、PE检测值与对照组比较有差异(P<0.05);亚临床期圆锥角膜组受检者ISV、KI、IVA、CKI、IHD、IHA、ABR、Rmin、CYL、AE、Kmax、PE检测值与对照组比较有差异(P<0.05);ROC曲线分析结果显示,IVA、KI、AE、PE、Rmin、IHD、Kmax、ISV、ABR诊断临床期圆锥角膜的敏感度和特异度均较高;IVA、Rmin、AE、PE诊断亚临床期圆锥角膜的敏感度和特异度均较高。结论:Pentacam眼前节分析仪可精确测量角膜前后表面形态学参数,其在圆锥角膜早期临床诊断中发挥重要作用。 展开更多
关键词 Pentacam眼前节分析仪 临床期圆锥角膜 亚临床期圆锥角膜
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动脉粥样硬化性疾病的DNA甲基化改变 被引量:1
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作者 伊珞 周宏宇 +2 位作者 仇鑫 李子孝 王拥军 《中国卒中杂志》 2022年第11期1162-1170,共9页
动脉粥样硬化是缺血性卒中、冠心病等心脑血管疾病的主要病因。既往研究发现DNA甲基化在动脉粥样硬化斑块的发生、进展中具有重要调节作用,并在病变的不同阶段表现出细胞特异性改变。本文综述了动脉粥样硬化斑块中内皮细胞、平滑肌细胞... 动脉粥样硬化是缺血性卒中、冠心病等心脑血管疾病的主要病因。既往研究发现DNA甲基化在动脉粥样硬化斑块的发生、进展中具有重要调节作用,并在病变的不同阶段表现出细胞特异性改变。本文综述了动脉粥样硬化斑块中内皮细胞、平滑肌细胞、巨噬细胞以及动脉粥样硬化性疾病患者外周血免疫细胞中DNA甲基化模式改变相关研究,总结了动脉粥样硬化性卒中患者的DNA甲基化改变,以期为新靶点的发现和疾病诊治提供新的思路。 展开更多
关键词 DNA甲基化 动脉粥样硬化 缺血性卒中
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Prognostic factors of refractory NSCLC patients receiving anlotinib hydrochloride as the third-or further-line treatment 被引量:46
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作者 Jing Wang yizhuo Zhao +18 位作者 Qiming Wang Li Zhang Jianhua Shi Zhehai Wang ying Cheng Jianxing He Yuankai Shi Hao Yu Yang Zhao Weiqiang Chen yi luo Xiuwen Wang Kejun Nan Faguang Jin Jian Dong Baolan Li Zhujun Liu Baohui Han Kai Li 《Cancer Biology & Medicine》 SCIE CAS CSCD 2018年第4期443-451,共9页
Objective:Anlotinib hydrochloride is a multitarget tyrosine kinase inhibitor that targets vascular endothelial growth factor receptor,fibroblast growth factor receptor,platelet-derived growth factor receptor,c-Kit,and... Objective:Anlotinib hydrochloride is a multitarget tyrosine kinase inhibitor that targets vascular endothelial growth factor receptor,fibroblast growth factor receptor,platelet-derived growth factor receptor,c-Kit,and c-MET;therefore,it exhibits both antitumor and anti-angiogenetic activities.A phase III trial has shown that anlotinib improved progression-free survival(PFS)and overall survival(OS)in patients with advanced non-small cell lung cancer(NSCLC),who presented with progressive disease or intolerance after standard chemotherapy.This study aimed to analyze the characteristics of patients receiving anlotinib treatment to determine the dominant populations who are fit for the treatment.Methods:Data were collected from March 2015 to January 2017 from a randomized,double-blind,placebo-controlled,multicenter,phase III trial of anlotinib(ALTER0303).A total of 437 patients were enrolled and randomly allocated(2:1)to the anlotinib and placebo groups.Kaplan–Meier analysis and log-rank test were performed to compare PFS and OS.Cox proportional hazards model was adopted for multivariate prognostic analysis.Results:Multivariate analysis indicated that high post-therapeutic peripheral blood granulocyte/lymphocyte ratio and elevated alkaline phosphatase levels were independent risk factors for PFS.Meanwhile,elevated thyroid-stimulating hormone,blood glucose,and triglyceride levels;hypertension;and hand–foot syndrome were independent protective factors of PFS.High posttherapeutic peripheral blood granulocyte/lymphocyte ratio,an Eastern Cooperative Oncology Group(ECOG)score≥2,and the sum of the maximal target lesion length at baseline were independent risk factors of OS,and hypertriglyceridemia was an independent protective factor of OS.Conclusions:This study preliminarily explored the possible factors that affected PFS and OS after anlotinib treatment in patients with advanced refractory NSCLC,and the baseline characteristics of the therapeutically dominant populations were then identified. 展开更多
关键词 NON-SMALL cell lung cancer anlotinib third- or further-line therapy PROGNOSTIC factor analysis
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阿帕替尼治疗复发性和进展性韧带样纤维瘤的疗效与安全性分析
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作者 方建国 王一天 +5 位作者 郑传禧 闵理 罗翼 周勇 段宏 屠重棋 《中国肿瘤临床》 CAS CSCD 北大核心 2021年第3期151-156,共6页
目的:分析阿帕替尼治疗复发性和进展性韧带样纤维瘤(desmoid fibromatosis,DF)的疗效和安全性。方法:收集2017年10月至2020年9月就诊于四川大学华西医院的复发性或进展性韧带样纤维瘤患者37例,接受靶向药物阿帕替尼治疗,起始剂量250 mg... 目的:分析阿帕替尼治疗复发性和进展性韧带样纤维瘤(desmoid fibromatosis,DF)的疗效和安全性。方法:收集2017年10月至2020年9月就诊于四川大学华西医院的复发性或进展性韧带样纤维瘤患者37例,接受靶向药物阿帕替尼治疗,起始剂量250 mg/d,根据药物不良反应调整剂量。结果:无完全缓解病例,17例(45.9%)为部分缓解,18例(48.6%)为疾病稳定,2例(5.4%)为疾病进展,客观有效率为45.9%,疾病控制率为94.6%。患者的关节活动度(rang of motion,ROM)、视觉模拟评分(visual analog scale,VAS)、上肢功能评定表(disabilities of the arm,shoulder and hand,DASH)评分、髋关节Harris评分及美国特种外科医院(HSS)评分均较治疗前有明显改善,且差异具有统计学意义(P<0.05)。常见的不良反应为手足综合征(37.8%)、胃肠反应(29.7%)和月经紊乱(21.6%)。结论:靶向药物阿帕替尼对复发性和进展性DF有一定的疗效,且不良反应可耐受,可作为复发性和进展性韧带样纤维瘤治疗的新途径。 展开更多
关键词 韧带样纤维瘤 阿帕替尼 疗效 不良反应
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