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西藏胡黄连中1个新的葫芦烷型糖苷化合物

中国中药杂志 2024年第7期49卷 1882-1887页

作者：吉海杰王舒王冬梅郝淑兰马祥雪仝立国路博丞李梅芳周文静史美军王晞星唐旭东山西省中医药研究院(山西省中医院) 山西太原030012 中国医学科学院北京协和医学院药物研究所北京100050 山西中医药大学山西太原030619 中国中医科学院西苑医院脾胃病研究所北京100091

采用柱色谱方法对西藏胡黄连Picrorhiza scrophulariiflora乙醇提取物进行提取分离,并通过HR-MS、1D和2D NMR等技术鉴定结构,同时采用CCK-8法检测细胞毒性。结果分离得到4个葫芦烷型糖苷,分别为2β-D-葡萄糖氧基-3β,16α,20β-三羟基-9... 详细信息

采用柱色谱方法对西藏胡黄连Picrorhiza scrophulariiflora乙醇提取物进行提取分离,并通过HR-MS、1D和2D NMR等技术鉴定结构,同时采用CCK-8法检测细胞毒性。结果分离得到4个葫芦烷型糖苷,分别为2β-D-葡萄糖氧基-3β,16α,20β-三羟基-9-甲基-19-去甲羊毛甾-5,25-二烯-22-酮(1)、2β-D-葡萄糖氧基-3β,16α,20β-三羟基-9-甲基-19-去甲羊毛甾-5,24-二烯-22-酮(2)、25-乙酰氧基-2β-葡萄糖氧基-3β,16α,20β-三羟基-9-甲基-19-去甲羊毛甾-5-烯-22-酮(3)、25-乙酰氧基-2β-葡萄糖氧基-3β,16α,20β-三羟基-9-甲基-19-去甲羊毛甾-5,23-(E)-二烯-22-酮(4),其中化合物1为1个新的葫芦烷型糖苷。对4种肿瘤细胞的半数抑制浓度均大于100μmol·L^(-1),表明这4个化合物无明显细胞毒作用。

关键词：西藏胡黄连葫芦烷型糖苷细胞毒性

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非相干扩频信号捕获算法研究和实现

信息技术 2024年第9期48卷 1-7,13页

作者：曾艳文胡一皓刘才瑞王晋阳梁显锋刘守印华中师范大学物理科学与技术学院武汉430079 中国科学院国家空间科学中心北京100190

研究了一种非相干扩频信号的捕获算法,用于星载S波段非相干扩频应答机实现一路遥控信号和四路测距信号的快速捕获。捕获单元采用并行FFT技术和分块-双倍补零技术实现对1kHz相干测距信号和2kHz非相干遥控信号的相关积分运算,在保证捕获... 详细信息

研究了一种非相干扩频信号的捕获算法,用于星载S波段非相干扩频应答机实现一路遥控信号和四路测距信号的快速捕获。捕获单元采用并行FFT技术和分块-双倍补零技术实现对1kHz相干测距信号和2kHz非相干遥控信号的相关积分运算,在保证捕获性能条件下抑制了数据跳变,对积分结果利用两级门限检测判决技术降低误捕概率,最后加入捕获验证算法抑制旁瓣干扰。仿真和测试结果表明,捕获单元能够抑制数据翻转,实现多通道相干和非相干扩频信号的快速捕获,且单通道捕获时间小于2s。

关键词：非相干扩频并行FFT 分块-双倍补零数据翻转多通道

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关键词与创新点词句群分布分析

情报学报 2007年第1期26卷 50-55页

作者：温有奎温浩西安电子科技大学经济管理学院西安710071 西安电子科技大学通信工程学院西安710071

本文对400篇《电子学报》论文中作者标出的关键词及作者提出的创新点词在正文中的句群分布做了统计分析。结果显示关键词0句群分布的概率为31．5％，关键词大于等于0．3的句群分布概率为40．5％，关键词与创新点词用词一致的概率为19．... 详细信息

本文对400篇《电子学报》论文中作者标出的关键词及作者提出的创新点词在正文中的句群分布做了统计分析。结果显示关键词0句群分布的概率为31．5％，关键词大于等于0．3的句群分布概率为40．5％，关键词与创新点词用词一致的概率为19．2％；创新点词具有引导特征词和适中的句群分布，由此提出增设创新点词标引的建议。试验表明，该方法不仅专指度高，且有利于创新点的知识单元发现。

关键词：关键词统计分析创新点词标引句群分布

Direct ZnO X-Ray Detector with Tunable Sensitivity

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Chinese Physics Letters 2019年第11期36卷 6-9页

作者： Hui-Li Liang Shu-Juan cui wen-Xing Huo Tao Wang Yong-Hui Zhang Bao-Gang Quan Xiao-Long Du Zeng-Xia Mei Key Laboratory for Renewable Energy Beijing Key Laboratory for New Energy Materials and DevicesBeijing National Laboratory for Condensed Matter PhysicsInstitute of PhysicsChinese Academy of SciencesBeijing 100190 School of Physical Sciences University of Chinese Academy of SciencesBeijing 100049 Laboratory of Microfabrication Beijing National Laboratory for Condensed Matter PhysicsInstitute of PhysicsChinese Academy of SciencesBeijing 100190 Songshan Lake Materials Laboratory Dongguan 523808

Direct ZnO x-ray detectors with tunable sensitivity are realized by delicately controlling the oxygen flux during the sputtering deposition process. The photocurrents induced by x-rays from a 40 kV x-ray tube with a Cu anode increase apparently as the oxygen flux decreases, which is attributed to the introduction of Vo *** introducing Vo defects, the annihilation rate of the photo-generated electron-hole pairs will be greatly slowed down, leading to a remarkable photoconductive gain. This finding informs a novel way to design the x-ray detectors based on abundant oxide materials.

关键词： materials. process. annihilation

Real time imaging of two-dimensional iron oxide spherulite nanostructure formation

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Nano Research 2019年第11期12卷 2889-2893页

作者： wenjing Zheng Matthew R.Hauwiller wen-I Liang Colin Ophus Peter Ercius Emory M.Chan Ying-hao Chu Mark Asta Xiwen Du A.Paul Alivisatos Haimei Zheng Institute of New-Energy Materials School of Materials Science and EngineeringTianjin UniversityTianjin300350China Materials Sciences Division Lawrence Berkeley National LaboratoryBerkeleyCA94720USA Department of Chemistry University of CaliforniaBerkeleyBerkeleyCA94720USA Department of Materials Science and Engineering “National Chiao Tung University”Hsinchu30010TaiwanChina The Molecular Foundry Lawrence Berkeley National LaboratoryBerkeleyCA94720USA Department of Materials Science and Engineering University of CaliforniaBerkeleyBerkeleyCA94720USA Kavli Energy NanoScience Institute University of California-Berkeley and Lawrence Berkeley National LaboratoryBerkeleyCA94720USA

The formation of complex hierarchical nanostructures has attracted a lot of attention from both the fundamental science and potential applications point of *** structures with radial fibrillar branches have been found in various solids;however,their growth mechanisms remain poorly ***,we report real time imaging of the formation of two-dimensional(2D)iron oxide spherulite nanostructures in a liquid cell using transmission electron microscopy(TEM).By tracking the growth trajectories,we show the characteristics of the reaction front and growth *** observations reveal that the tip of a growing branch splits as the width exceeds certain sizes(5.5–8.5 nm).The radius of a spherulite nanostructure increases linearly with time at the early stage,transitioning to nonlinear growth at the later ***,a thin layer of solid is accumulated at the tip and nanoparticles from secondary nucleation also appear at the growing front which later develop into fibrillar *** spherulite nanostructure is polycrystalline with the co-existence of ferrihydrite and Fe3O4 through-out the growth.A growth model is further established,which provides rational explanations on the linear growth at the early stage and the nonlinearity at the later stage of growth.

关键词： liquid cell transmission electron microscopy(TEM) in situ TEM iron oxide spherulite nanostructures

Efficacy and Safety of Washed Microbiota Transplantation to Treat Patients with Mild-to-Severe COVID-19 and Suspected of Having Gut Microbiota Dysbiosis: Study Protocol for a Randomized Controlled Trial

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Current Medical Science 2021年第6期41卷 1087-1095页

作者： Li-hao WU Zhi-ning YE Ping PENG wen-rui XIE Jia-ting XU Xue-yuan ZHANG Harry Hua-xiang XIA Xing-xiang HE Department of Gastroenterology the First Affiliated Hospital of Guangdong Pharmaceutical UniversityGuangzhou 510080China Research Center for Engineering Techniques of Microbiota-Targeted Therapies of Guangdong Province the First Affiliated Hospital of Guangdong Pharmaceutical UniversityGuangzhou 510080China Guangzhou Eighth People's Hospital Guangzhou 510060China

Objective:Coronavirus disease 2019(COVTD-19)is often accompanied by gastrointestinal symptoms,which are related to gut microbiota dysbiosis(GMD).Whether washed microbiota transplantation(WMT)is an effective treatment for COV1D-19 patients suspected of having GMD by restoring the gut microbiota is *** study is designed to explore the efficacy and safety of WMT in COVID-19 patients suspected of having ***:This is a randomized,multicenter,single-blind prospective ***-19 patients suspected of having GMD will be randomly divided to receive routine treatment only or to receive routine treatment and *** frequency of WMT will be once a day for three consecutive *** and imaging examinations will be performed at admission,1 and 2 weeks after treatment,and on the day of *** a telephone follow-up will be conducted at 1st week,2nd week,and 6th month after *** clinical efficacy and safety of WMT in COVD-19 patients suspected of having GMD and the effects of WMT on the organ function,homeostasis,inflammatory response,intestinal mucosal barrier function,and immunity of the patients will be ***:By following the proposed protocol,WMT is expected to be efficacious and safe for the treatment of COVID-19 patients suspected of having GMD,and the therapeutic effect is expected to be associated with improvement of the intestinal mucosal barrier function,inflammatory response,and ***:The findings from this study may offer a new approach for the prevention and treatment of COVID-19 patients suspected of having GMD.

关键词： COVID-19 SARS-Cov-2 virus gut microbiota microbiome dysbiosis washed microbiota transplantation

m6A RNA methylation-mediated HNF3γ reduction rendershepatocellular carcinoma dedifferentiation and sorafenibresistance

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Signal Transduction and Targeted Therapy 2021年第1期6卷 144-157页

作者： Tengfei Zhou Shichao Li Daimin Xiang Junyu Liu wen Sun Xiuliang cui Beifang Ning Xiao Li Zhuo Cheng Weiqi Jiang Cheng Zhang Xijun Liang Liang Li Xin Cheng Liu Hui Hongyang Wang Jin Ding International Cooperation Laboratory on Signal Transduction Eastern Hepatobiliary Surgery Hospital/InstituteThe Second Military Medical UniversityShanghaiChina Department of Gastroenterology Changzheng HospitalThe Second Military Medical UniversityShanghaiChina Shanghai Institutes for Biological Sciences Chinese Academy of SciencesShanghaiChina The Third Department of Hepatic Surgery Eastern Hepatobiliary Surgery HospitalThe Second Military Medical UniversityShanghaiChina National Center for Liver Cancer ShanghaiChina Tongji University School of Medicine ShanghaiChina

Hepatocyte nuclear factor 3γ(HNF3γ)is a hepatocyte nuclear factor,but its role and clinical significance in hepatocellular carcinoma(HCC)remain ***,we report that HNF3γexpression is downregulated in patient HCC and inversely correlated with HCC malignancy and patient ***,our data suggested that the HNF3γreduction in HCC could be mediated by METTL14-dependent m6A methylation of HNF3γ***3γexpression was increased during hepatic differentiation and decreased in dedifferentiated HCC ***,HNF3γdelivery promoted differentiation of not only HCC cells but also liver CSCs,which led to suppression of HCC *** analysis suggested an HNF3γ-centered regulatory network that includes essential liver differentiation-associated transcription factors and functional molecules,which could synergistically facilitate HCC cell *** importantly,enforced HNF3γexpression sensitized HCC cells to sorafenib-induced growth inhibition and cell apoptosis through transactivation of OATP1B1 and OATP1B3 expression,which are major membrane transporters for sorafenib *** investigation showed that patient-derived HCC xenografts with high HNF3γexpression exhibited a sorafenib response and patients with high HCC HNF3γlevels benefited from sorafenib ***,these results suggest that HNF3γplays an essential role in HCC differentiation and may serve as a therapeutic target and predictor of sorafenib benefit in patients.

关键词： sorafenib hepatocellular mediated

CPEB1,a novel risk gene in recent-onset schizophrenia,contributes to mitochondrial complex I defect caused by a defective provirus ERVWE1

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World Journal of Psychiatry 2021年第11期11卷 1075-1094页

作者： Ya-Ru Xia Xiao-cui Wei wen-Shi Li Qiu-Jin Yan Xiu-Lin Wu Wei Yao Xu-Hang Li Fan Zhu State Key Laboratory of Virology and Hubei Province Key Laboratory of Allergy&Immunology Department of Medical MicrobiologySchool of MedicineWuhan UniversityWuhan 430071Hubei ProvinceChina

BACKGROUND Schizophrenia afflicts 1%of the world *** studies suggest that schizophrenia patients may have an imbalance of mitochondrial energy metabolism via inhibition of mitochondrial complex I ***,recent studies have shown that ERVWE1 is also a risk factor for ***,there is no available literature concerning the relationship between complex I deficits and ERVWE1 in *** risk factors and blood-based biomarkers for schizophrenia may provide new guidelines for early interventions and prevention *** To address novel potential risk factors and the underlying mechanisms of mitochondrial complex I deficiency caused by ERVWE1 in *** Quantitative polymerase chain reaction(qPCR)and enzyme-linked immunosorbent assay were used to detect differentially expressed risk factors in blood *** statistical analyses were performed by median analyses and Mann-Whitney U ***’s rank correlation was applied to examine the correlation between different risk factors in blood ***,western blot analysis,and luciferase assay were performed to confirm the relationship among ERVWE1,cytoplasmic polyadenylation element-binding protein 1(CPEB1),NADH dehydrogenase ubiquinone flavoprotein 2(NDUFV2),and NDUFV2 pseudogene(NDUFV2P1).The complex I enzyme activity microplate assay was carried out to evaluate the complex I activity induced by *** Herein,we reported decreasing levels of CPEB1 and NDUFV2 in schizophrenia *** studies showed that ERVWE1 was negatively correlated with CPEB1 and NDUFV2 in ***,NDUFV2P1 was increased and demonstrated a significant positive correlation with ERVWE1 and a negative correlation with NDUFV2 in *** vitro experiments disclosed that ERVWE1 suppressed NDUFV2 expression and promoter activity by increasing NDUFV2P1 *** luciferase assay revealed that ERVWE1 could enhance the promoter

关键词： ERVWE1 CPEB1 NADH dehydrogenase ubiquinone flavoprotein 2 complex I Pseudogene

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亚波长薄膜堆栈超构材料:理论及应用

红外与毫米波学报 2022年第1期41卷 151-168页

作者：文政绩李晓温赵文超孙艳郝加明戴宁褚君浩中国科学院上海技术物理研究所红外物理国家重点实验室上海200083 湖州学院电子与信息系浙江湖州313000 复旦大学光电研究院上海200433 国科大杭州高等研究院物理与光电工程学院浙江杭州310024

亚波长薄膜堆栈超构材料,作为超构材料领域一个特殊的组成部分,因其具有亚波长厚度、无需复杂光刻加工以及可低成本大面积制备等诸多优点,吸引了人们越来越多的关注。本文聚焦回顾近些年亚波长薄膜堆栈超构材料相关研究进展,首先简要回... 详细信息

亚波长薄膜堆栈超构材料,作为超构材料领域一个特殊的组成部分,因其具有亚波长厚度、无需复杂光刻加工以及可低成本大面积制备等诸多优点,吸引了人们越来越多的关注。本文聚焦回顾近些年亚波长薄膜堆栈超构材料相关研究进展,首先简要回顾了多层薄膜堆栈体系的基础理论研究方法,侧重介绍了亚波长薄膜堆栈超构材料的新理论新设计;接着,着重介绍了基于亚波长薄膜堆栈超构材料的若干典型应用,具体包括结构色调控、光致发光增强、窄带红外光源、红外伪装以及其他一些有趣应用;最后,探讨并展望了亚波长薄膜堆栈超构材料领域未来的发展方向以及其可能遇到的问题挑战。

关键词：超构材料亚波长薄膜堆栈光学器件