检索结果-南通市图书馆

甘肃北山红旗山井岩体锆石U-Pb定年、地球化学特征及地质意义

在线全文

学校读者我要写书评

暂无评论

科学技术与工程 2024年第25期24卷 10688-10700页

作者：陈杰赵吉昌杨镇熙雷自强张玉鹏李创远甘肃省地质矿产勘查开发局第四地质矿产勘查院酒泉735000 甘肃省矿产资源勘查重点实验室酒泉735000

北山地区岩浆岩分布广泛,这些侵入岩的形成年龄时间可从早古生代跨至中生代。尽管前人对北山地区岩浆岩形成年龄开展了大量研究,然而多集中于对古生代岩浆岩的研究,而较少关注中生代岩浆。对甘肃北山红旗山井斑状二长花岗岩的年龄做了... 详细信息

北山地区岩浆岩分布广泛,这些侵入岩的形成年龄时间可从早古生代跨至中生代。尽管前人对北山地区岩浆岩形成年龄开展了大量研究,然而多集中于对古生代岩浆岩的研究,而较少关注中生代岩浆。对甘肃北山红旗山井斑状二长花岗岩的年龄做了高精度的激光剥蚀电感耦合等离子体质谱(laser ablation inductively coupled plasma mass spectrometry,LA-ICP-MS)锆石U-Pb测年,获得其年龄加权平均值为(237.6±1.1)Ma(平均标准权重偏差MSWD=0.44),为中三叠世岩浆活动的产物。岩石地球化学数据表明,该岩体具高硅(SiO_(2)=67.17%~68.33%),高铝(Al 2O 3=15.02%~15.82%),贫镁(MgO=1.07%~1.18%),以及富钠、钾(Na_(2) O=3.35%~3.75%,K_(2) O=4.2%~4.38%,Na_(2) O/K_(2) O=0.80~0.85)等特征,TiO_(2)含量为0.57%~0.64%,CaO含量2.39%~2.6%。轻、重稀土明显分馏,LREE/HREE为36.86~44.52,轻稀土明显富集,具轻微的Eu负异常。微量元素分析发现岩石中明显富集大离子亲石元素Ba及强不相容元素Th、U,亏损Nb、Ta、Ti、Y、Yb、Lu等高场强元素,表现出I型花岗岩的特征。因此,结合区域构造特征,认为在中三叠世时期,北山洋盆尚未闭合,而北山南带处于大洋板块俯冲的大陆边缘岛弧环境。

关键词：斑状二长花岗岩锆石U-Pb 岩石地球化学大洋板块俯冲北山地区

红花提取物通过调节PI3K/Akt/FoxO信号通路改善酒精性肝病

在线全文

学校读者我要写书评

暂无评论

中国药理学通报 2024年第6期40卷 1137-1145页

作者：王文萱付向磊戚曼范芙蓉朱芙蓉王元创张凯月刘敏楚生辉石河子大学药学院新疆植物药资源利用教育部重点实验室新疆石河子832000

目的探讨红花提取物(Carthamus tinctorius ***,CTLE)对酒精诱导的肝损伤小鼠氧化应激、脂质代谢和凋亡水平的影响及其作用机制。方法采用慢性酒精喂养加急性酒精灌胃的酒精性肝病小鼠模型造模。小鼠被随机分为4组,造模期间每天观察小... 详细信息

目的探讨红花提取物(Carthamus tinctorius ***,CTLE)对酒精诱导的肝损伤小鼠氧化应激、脂质代谢和凋亡水平的影响及其作用机制。方法采用慢性酒精喂养加急性酒精灌胃的酒精性肝病小鼠模型造模。小鼠被随机分为4组,造模期间每天观察小鼠状态变化并记录体质量。造模结束后,收集各组小鼠血液和肝脏组织。对小鼠血液进行生化分析。HE染色和油红O染色进一步评价小鼠肝脏病理损伤程度。应用实时荧光定量PCR(quantitative real-time PCR,qPCR)和Western blot法检测p-PI3K、PI3K、p-Akt、Akt、p-mTOR、mTOR、p-FoxO1、FoxO1、p-FoxO3a、FoxO3a、p-FoxO4、FoxO4、BCL-2和BAX因子的mRNA和蛋白表达水平。结果与模型组相比,CTLE给药组小鼠肝脏病理损伤程度和脂质沉积有所改善;小鼠血清及肝脏中的生化相关指标,如ALT、AST、TG、TC、MDA水平有所降低,GSH、SOD水平有所升高。并且通过调控PI3K/Akt/FoxO通路产生了更多的SOD,减少了活性氧(reactive oxygen species,ROS)对机体的损伤和细胞凋亡。结论CTLE可以通过PI3K/Akt/FoxO通路发挥抗氧化应激和抗凋亡作用,减轻小鼠的酒精性肝损伤,为治疗酒精性肝病和开发相关药物提供新的思路。

关键词：红花提取物酒精性肝病脂质代谢氧化应激细胞凋亡 PI3K/Akt/FoxO信号通路

维普期刊数据库博看期刊

Breakdown characteristics of CF4 and CF4/N2 hybrid gas in refrigeration temperature range

在线全文

学校读者我要写书评

暂无评论

Journal of Central South University 2017年第4期24卷 861-865页

作者： HOU Meng-xi LI Wei-guo yuan chuang-ye YANG Yi-xin OUYANG Jie School of Electrical and Electronic Engineering North China Electric Power University Beijing 102206 China Measuring Center of State Grid Hunan Electric Power Corp Changsha 410000 China

Common insulation gas cannot normally work in refrigeration temperature range(153-243 K), especially in extremely cold regions. To solve this problem, this essay uses cubic equation combined with two-parameter model in theorem of corresponding states to estimate dew-point of hybrid gas. The influence of temperature on mixing ratio is studied by using van der Waals equation. The result shows that the mixing ratio is stable during temperature-fall period. Insulation property of CF_4 and CF_4/N_2 in refrigeration temperature range is studied through self-designed low-temperature test system. The result shows when the density of hybrid gas is invariable, temperature changing has less influence on breakdown voltage, and when the mixing ratio is 20%, CF_4/N_2 is the greatest potential hybrid gas.

关键词： dew-point refrigeration temperature range CF4 gas insulation

Applications and prospects of cryo-EM in drug discovery

在线全文

学校读者我要写书评

暂无评论

Military Medical Research 2023年第6期10卷 848-861页

作者： Kong-Fu Zhu chuang yuan Yong-Ming Du Kai-Lei Sun Xiao-Kang Zhang Horst Vogel Xu-Dong Jia yuan-Zhu Gao Qin-Fen Zhang Da-Ping Wang Hua-Wei Zhang Department of Biomedical Engineering Southern University of Science and TechnologyShenzhen 518055GuangdongChina Department of Biochemistry and Molecular Biology School of Basic Medical SciencesPeking UniversityBeijing 100191China Department of Structural Biology St.Jude Children’s Research HospitalMemphisTN 38105USA Center for Protein Science and Crystallography School of Life SciencesFaculty of ScienceChinese University of Hong KongHong Kong 999077China Interdisciplinary Center for Brain Information the Brain Cognition and Brain Disease InstituteShenzhen Institute of Advanced TechnologyChinese Academy of SciencesShenzhen 518055GuangdongChina Faculty of Life and Health Sciences Shenzhen Institute of Advanced TechnologyChinese Academy of SciencesShenzhen 518055GuangdongChina Shenzhen-Hong Kong Institute of Brain Science-Shenzhen Fundamental Research Institutions Shenzhen 518055GuangdongChina Shenzhen Institute of Advanced Technology Chinese Academy of SciencesShenzhen 518055GuangdongChina State Key Lab for Biocontrol School of Life SciencesSun Yat-Sen UniversityGuangzhou 510275China Cryo‑EM Facility Center Southern University of Science and TechnologyShenzhen 518055GuangdongChina Department of Orthopedics Shenzhen Intelligent Orthopaedics and Biomedical Innovation PlatformGuangdong Provincial Research Center for Artifcial Intelligence and Digital Orthopedic TechnologyShenzhen Second People’s HospitalThe First Affiliated Hospital of Shenzhen UniversityShenzhen 518000GuangdongChina Guangdong Provincial Key Laboratory of Advanced Biomaterials Southern University of Science and TechnologyShenzhen 518055GuangdongChina

Drug discovery is a crucial part of human healthcare and has dramatically benefited human lifespan and life quality in recent centuries, however, it is usually time-and effort-consuming. Structural biology has been demonstrated as a powerful tool to accelerate drug development. Among different techniques, cryo-electron microscopy(cryo-EM) is emerging as the mainstream of structure determination of biomacromolecules in the past decade and has received increasing attention from the pharmaceutical industry. Although cryo-EM still has limitations in resolution, speed and throughput, a growing number of innovative drugs are being developed with the help of cryo-EM. Here, we aim to provide an overview of how cryo-EM techniques are applied to facilitate drug discovery. The development and typical workflow of cryo-EM technique will be briefly introduced, followed by its specific applications in structure-based drug design, fragment-based drug discovery, proteolysis targeting chimeras, antibody drug development and drug repurposing. Besides cryo-EM, drug discovery innovation usually involves other state-of-the-art techniques such as artificial intelligence(AI), which is increasingly active in diverse areas. The combination of cryo-EM and AI provides an opportunity to minimize limitations of cryo-EM such as automation, throughput and interpretation of mediumresolution maps, and tends to be the new direction of future development of cryo-EM. The rapid development of cryo-EM will make it as an indispensable part of modern drug discovery.

关键词： Cryo-electron microscopy(cryo-EM) Drug discovery Structure-based drug design Fragment-based drug discovery Proteolysis targeting chimeras Drug repurposing Artificial intelligence(AI)

A novel AMH variant at the prehelix loop impairs the binding to AMHR2 and causes persistent Mullerian duct syndrome

在线全文

学校读者我要写书评

暂无评论

Asian Journal of Andrology 2024年第2期26卷 222-224页

作者： Qiang Du chuang Qiu yuan-yuan Zhang Xue-Jun Shang Xiao-Liang Liu Center of Reproductive Medicine Shengjing Hospital of China Medical UniversityShenyang 110004China Department of Orthopedics Shengjing Hospital of China Medical UniversityShenyang 110004China Department of Clinical Genetics Shengjing Hospital of China Medical UniversityShenyang 110004China Department of Urology Jinling HospitalSchool of MedicineNanjing UniversityNanjing 210012China

Dear Editor,Persistent Mullerian duct syndrome(PMDS;Online Mendelian Inheritance in Man[OMIM]:#261550)is a rare autosomal recessive inherent difference in sex development in males with Mullerian duct derivatives,including the uterus,fallopian tubes,and upper part of the vagina.'Approximately 88%of PMDS patients were found to have biallelic variants in the anti-Mullerian hormone(AMH;OMIM:*600957)or AMH type 2 receptor(AMHR2;OMIM:*600956)genes,and the rest were referred as idiopathic.I The serum AMH levels are usually very low or undetectable in PMDS patients with AMH gene mutations but normal or elevated in those with AMHR2 gene ***,an adult Chinese patient with PMDS carrying biallelic variants of the AMH gene was reported to have unexpectedly normal serum AMH *** refer to Supplementary Information of Patient and Methods for methodologies.

关键词： elevated AMH Muller

Thioacetamide Additive Homogenizing Zn Deposition Revealed by In Situ Digital Holography for Advanced Zn Ion Batteries

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Nano-Micro Letters 2024年第6期16卷 261-275页

作者： Kaixin Ren Min Li Qinghong Wang Baohua Liu chuang Sun Boyu yuan Chao Lai Lifang Jiao Chao Wang School of Chemistry and Materials Science Jiangsu Normal UniversityXuzhou 221116JiangsuPeople’s Republic of China Jiangsu Key Laboratory of Advanced Laser Materials and Devices School ofPhysics and Electronic EngineeringJiangsu Normal UniversityXuzhou 221116JiangsuPeople’s Republic of China Key Laboratory of Advanced Energy Materials Chemistry(Ministry of Education) Nankai University300071 TianjinPeople’s Republic of China

Zinc ion batteries are considered as potential energy storage devices due to their advantages of low-cost,high-safety,and high theoretical ***,dendrite growth and chemical corrosion occurring on Zn anode limit their *** problems can be tackled through the optimization of the ***,the screening of electrolyte additives using normal electrochemical methods is time-consuming and ***,a fast and simple method based on the digital holography is *** can realize the in situ monitoring of electrode/electrolyte interface and provide direct information concerning ion concentration evolution of the diffusion *** is effective and time-saving in estimating the homogeneity of the deposition layer and predicting the tendency of dendrite growth,thus able to value the applicability of electrolyte *** feasibility of this method is further validated by the forecast and evaluation of thioacetamide *** on systematic characterization,it is proved that the introduction of thioacetamide can not only regulate the interficial ion flux to induce dendrite-free Zn deposition,but also construct adsorption molecule layers to inhibit side reactions of Zn *** easy to operate,capable of in situ observation,and able to endure harsh conditions,digital holography method will be a promising approach for the interfacial investigation of other battery systems.

关键词： Digital holographic microscopy In situ observation Electrode/electrolyte interface Zn dendrites Screening electrolyte additives

在线全文

学校读者我要写书评

暂无评论

试论科学技术的社会沟通

科学技术与辩证法 2008年第6期25卷 102-106页

作者：袁闯复旦大学哲学学院上海200433

科学技术的高速发展引起科学技术与社会其他方面的对立与分离。文章提出科学技术的社会沟通的概念,试图引起对上述现象的重视并讨论其解决办法,以期对科学技术与社会的和谐发展有所帮助。

关键词：科学技术的社会沟通科技沟通科技传播

在线全文

学校读者我要写书评

暂无评论

关于高校如何为残疾大学生服务的思考

图书馆 2006年第4期 84-85,88页

作者：袁闯吉首大学图书馆湖南吉首416000

基于对残疾大学生思想感情特征及其面临的实际困难与问题的分析,本文简要论述了高校相关职能部门应为残疾大学生提供的特殊服务。

关键词：高校残疾大学生特殊服务

Breakdown mechanism of CF_4 and N_2 binary gas in refrigeration temperature range

在线全文

学校读者我要写书评

暂无评论

Journal of Central South University 2018年第7期25卷 1701-1707页

作者： LI Wei-guo HOU Meng-xi yuan chuang-ye CHENG Yu-di TU You-ping School of Electrical and Electronic Engineering North China Electric Power UniversityBeijing 102206China

The mechanism of gas discharge in refrigeration temperature range is still not clear. N2, CF4, 20% CF4＋N2 and 50%CF4＋50%N2 binary gas mixtures were tested under the conditions of –153–25 ℃ and 50–2000 Pa. The experimental results show that the minimum of Paschen curves of all test samples shifts to low pressure, from 500 Pa to 200 Pa. The value of Paschen curve minimum of N2 shows remarkable fluctuation. This fluctuation is explained by molecule agglomeration and electronic mean energy. The fluctuation decreases with the increasing mixing ratio of CF4. What’s more, the value of Paschen curve minimum of CF4 decreases with temperature. This phenomenon is ascribed to attach-radiation and secondary process.

关键词： CF4 N2 agglomeration attach-radition breakdown mechanism refrigeration temperature range