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Chinese Chemical Letters 2007年第5期18卷 505-508页

作者： Chun xia Tan Ruo Fei Feng xiao xia peng The College of Traditional Medicine of Gansu Lanzhou 730030 China Life Science ＆ Engineering College Northwest University for Nationalities Lanzhou 730030 China

By the condensation of 2,6-bis（4-amino-5-mercapto-[1,2,4]-triazoles-2）pyridine with aromatic acid in the presence of phosphorus oxychloride. Compounds of 2,6-bis（6-aryl-[1,2,4]-triazolo[3,4-b][1,3,4]-thiadiazole-3-yl）pyridines were synthesized. Their structures were confirmed by IR, ^1H NMR spectroscopies and elemental analysis. Their electrochemical behavior and cyclic voltammogram also were be studied. The results showed that they have high ionization potentials and good affinity.

关键词： Synthesis Triazolo-thiadiazoles Electrochemical properties

Scheme for Implementing Quantum Dense Coding and Teleportation with Tripartite Entangled State in Cavity QED

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Communications in Theoretical Physics 2008年第11期50卷 1113-1116页

作者： JIA Chun-xia peng Zhao-Hui Department of Physics Hunan University of Science and Technology Xiangtan 411201 China

In this paper, we present a peculiar tripartite entangled state that is inequivalent to both the GHZ state and the W state, and then propose to implement efficient quantum information processing such as quantum dense coding and teleportation with this entangled state in cavity QED. In this scheme the atoms interact with a highly detuned cavity field with the assistance of a strong classical driven field. It does not require the transfer of quantum information between the atomic system and the cavity, and then our scheme is insensitive to both the cavity decay and the thermal field.

关键词： dense coding teleportation cavity QED

齐墩果酸通过miR-18a-5p/STK4轴抑制白血病K562细胞恶性进展

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中国生物化学与分子生物学报 2024年第5期40卷 708-720页

作者：谢波来永巍韩旭徐岩王迪迪张鹏霞佳木斯大学基础医学院生物化学与分子生物学教研室黑龙江佳木斯154007

慢性粒细胞白血病(chronic myeloid leukemia,CML)是由于骨髓造血干细胞的恶性增生导致的疾病。虽然酪氨酸激酶抑制剂(Tyrosine kinase inhibitors,TKI)对慢性粒细胞性白血病的治疗取得长足进展,但耐药问题仍未解决。因此,寻找新的治疗... 详细信息

慢性粒细胞白血病(chronic myeloid leukemia,CML)是由于骨髓造血干细胞的恶性增生导致的疾病。虽然酪氨酸激酶抑制剂(Tyrosine kinase inhibitors,TKI)对慢性粒细胞性白血病的治疗取得长足进展,但耐药问题仍未解决。因此,寻找新的治疗药物和靶点十分关键。有研究表明,miRNAs与慢性粒细胞白血病在内的多种肿瘤有密切联系,齐墩果酸(oleanolic acid,OA)对白血病细胞有较好的抑制效果。通过对转录物组测序结果发现,齐墩果酸可以显著上调丝氨酸/苏氨酸蛋白质激酶4(serine/threonine-protein kinase 4,STK 4)的水平,而miR1a-5p是STK 4的靶miRNA。因此,本文旨在探究齐墩果酸是否可以通过miR-18a-5p/STK4影响K562细胞恶性进展。K562细胞经齐墩果酸处理后差异表达基因富集在凋亡相关通路上。EdU实验和CCK-8实验结果发现,齐墩果酸降低K562细胞增殖能力(P<0.05)。qRT-PCR,免疫荧光和Western印迹结果显示,齐墩果酸处理后,K562细胞中STK 4蛋白质水平表达显著上调(P<0.05),miR-18a-5p表达下调(P<0.05)。在细胞中转染miR-18a-5p mimics,能显著抑制STK 4的表达(P<0.05);转染miR-18a-5p inhibitor能显著增加STK 4的表达(P<0.05)。活性氧(reactive oxygen species、ROS)检测和线粒体膜电位检测结果显示,齐墩果酸可以促进K562细胞中ROS的增加,降低线粒体膜电位。过表达STK 4后,与Vector组相比,细胞的线粒体膜电位下降;敲降STK 4可以逆转齐墩果酸组导致的线粒体膜电位下降。流式细胞术检测显示,齐墩果酸能明显促进细胞凋亡的发生,而转染miR-18a-5p mimics后凋亡率显著下调(P<0.05);过表达STK 4可以促进细胞从早期凋亡向晚期凋亡转化,而同时转染miR-18a-5p mimics可以抑制这一现象。我们的研究结果证实,齐墩果酸可以通过维持miR-18a-5p的低表达和保持STK 4的高表达状态来促进K562细胞的凋亡。

关键词：齐墩果酸 K562 miR-18a-5p 丝氨酸/苏氨酸蛋白质激酶4 细胞凋亡

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伏诺拉生抗幽门螺杆菌治疗中的疗效观察

药物生物技术 2024年第2期31卷 181-184页

作者：金迪夏鹏飞余意武汉市中医医院脾胃肝胆病科湖北武汉430000

观察伏诺拉生(VNP)治疗幽门螺杆菌(Hp)的疗效及安全性。纳入240例Hp感染的慢性胃炎患者,随机数表法分为质子泵抑制剂(PPI)14 d组、VNP 14 d组、VNP 7 d组,每组80例。PPI 14 d组给予雷贝拉唑20 mg bid+胶体果胶铋颗粒200 mg bid+阿莫西... 详细信息

观察伏诺拉生(VNP)治疗幽门螺杆菌(Hp)的疗效及安全性。纳入240例Hp感染的慢性胃炎患者,随机数表法分为质子泵抑制剂(PPI)14 d组、VNP 14 d组、VNP 7 d组,每组80例。PPI 14 d组给予雷贝拉唑20 mg bid+胶体果胶铋颗粒200 mg bid+阿莫西林胶囊1000 mg bid+克拉霉素片500 mg bid治疗,疗程为14 d;VNP 7 d组给予富马酸伏诺拉生片20 mg bid+阿莫西林胶囊1000 mg bid治疗,疗程为7 d;VNP 14 d组给予富马酸伏诺拉生片20 mg bid+阿莫西林胶囊1000 mg bid治疗,疗程为14 d。治疗结束停药4~6 w后,空腹行^(13)C-尿素呼气试验复查Hp,比较三组Hp根除率及不良反应发生率。PPI 14 d组、VNP 14 d组和VNP 7 d组分别有76例、77例、74例患者完成了治疗。根据意向性治疗(ITT)分析,PPI 14 d组、VNP 14 d组、VNP 7 d组的根除率分别为80.0%、83.8%、76.3%;根据实验方案(PP)分析三组的根除率分别为84.2%、87.0%、82.4%;三组患者Hp清除率比较,差异无明显统计学意义(χ^(2)ITT分析=1.41,χ^(2)PP分析=0.62,P>0.05)。3组所有不良事件均为轻度,不良反应发生率分别为8.8%、11.3%和8.8%,差异无统计学意义(P>0.05)。VNP 7 d方案耐受性良好,其疗效和安全性与PPI 14 d方案和VNP 14 d方案相似,或可作为根除Hp的推荐方案之一。

关键词：幽门螺杆菌四连方案伏诺拉生根除治疗慢性胃炎质子泵抑制剂

Studies on the esterifications of 9-(hydroxyimino)-4-methyl-8,9-dihydrofuro[2,3-h]chromen-2-one with acid chlorides under different conditions

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Chinese Chemical Letters 2008年第7期19卷 791-794页

作者： Ru Shu Sun Yang Wang peng xia Department of Medicinal Chemistry School of Pharmacy Fudan University Shanghai 200032 China

The esterifications of 9-（hydroxyimino）-4-methyl-8,9-dihydrofuro[2,3-h]chromen-2-one （4） with acid chlorides afforded normal oxime-esters 3a-e in 35-78% yields in presence of excessive 4-dimethylaminopyridine as the acid scavenger, whereas the reactions gave unexpected 8-substituted products N-（8-chloro-4-methyl-2-oxo-2H-furo-[2,3-h]chromen-9-yl）amides （5a-c） and 4-methyl-2,9-dioxo-8,9-dihydro-2H-furo[2,3-h]chromen-8-ylcarboxyloates （6d-e） by using excessive acid chlorides. The structures of 10 new compounds were determined by 1H NMR, 13C NMR, MS and HRMS, and the possible mechanism for the formation of unexpected products 5a--c and 6d-e was also proposed.

关键词： 9-(Hydroxyirnino)-4-methyl-8,9-dihydrofuro[2,3-h]chromen-2-one Oxime-ester N-(8-Chloro-4-methyl-2-oxo-2H-furo[2,3-h]chro-men-9-yl)amide 4-Methyl-2,9-dioxo-8,9-dihydro-2H-furo[2,3-h]chromen-8-ylcarboxyloate

不同时间尺度红树林演化的示踪方法及受控机制

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海洋地质与第四纪地质 2024年第3期44卷 197-210页

作者：张尧孟宪伟夏鹏张道来张俊徐元芹潘良浩邱广龙中国地质调查局青岛海洋地质研究所青岛266237 自然资源部北方滨海盐沼湿地生态地质野外科学观测研究站青岛266237 自然资源部第一海洋研究所青岛266061 广西海洋科学院(广西红树林研究中心) 广西红树林保护与利用重点实验室北海536000

红树林具有多重生态系统服务功能,是减缓和适应气候变化的战略要地,其对未来全球变化的响应可通过重建过去红树林的演化来实现,进而为制定适应不同战略需求的短期/长期红树林保护和修复方案奠定科学基础。本文归纳了红树植物花粉、有机... 详细信息

红树林具有多重生态系统服务功能,是减缓和适应气候变化的战略要地,其对未来全球变化的响应可通过重建过去红树林的演化来实现,进而为制定适应不同战略需求的短期/长期红树林保护和修复方案奠定科学基础。本文归纳了红树植物花粉、有机碳氮及其稳定同位素和三萜类化合物等红树林演化示踪指标的优缺点,并对红树林有机碳来源定量判识方法进行了介绍;重点从长时间尺度(晚白垩世以来和全新世以来)和短时间尺度(近百年来和近几十年来)回顾和总结了红树林起源、进化、灭绝、迁移、兴衰和演替等多样化的演化历史;揭示了自然环境(构造运动、海平面、气候和水文环境等)和人类活动(海水养殖、围垦、伐木、工程建设和人工保护修复等)对红树林演化的控制作用;最后提出了未来在深化红树林演化研究领域的关键科学目标。

关键词：红树林演化红树林源有机碳海平面和气候变化人类活动全新世近百年来

Mangrove forest degradation indicated by mangrove-derived organic matter in the Qinzhou Bay,Guangxi,China,and its response to the Asian monsoon during the Holocene climatic optimum

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Acta Oceanologica Sinica 2016年第2期35卷 95-100页

作者： MENG xianwei xia peng LI Zhen LIU Lejun First Institute of Oceanography State Oceanic Administration Laboratory for Marine Geology and Environment Qingdao National Laboratory for Marine Science and Technology State Key Laboratory of Estuarine and Coastal Research East China Normal University

The response of mangrove ecosystems to the Asian monsoon in the future global warming can be understood by reconstructing the development of mangrove forests during the Holocene climatic optimum（HCO）, using proxies preserved in coastal sediments. The total organic matter in sediments of a segmented core, with calibrated age ranges between 5.6 and 7.7 cal. ka BP and corresponding to the HCO, from the Qinzhou Bay in Guangxi, China, is quantitatively partitioned into three end-members according to their sources： mangrove-derived, terrigenous,and marine phytoplanktonic, using a three-end-member model depicted by organic carbon isotope（δ13Corg） and the molar ratio of total organic carbon to total nitrogen（C/N）. The percentage of mangrove-derived organic matter（MOM） contribution is used as a proxy for mangrove development. Three visible drops in MOM contribution occurred at ca. 7.3, ca. 6.9, and ca. 6.2 cal. ka BP, respectively, are recognized against a relatively stable and higher MOM contribution level, indicating that three distinct mangrove forest degradations occurred in the Qinzhou Bay during the HCO. The three mangrove forest degradations approximately correspond to the time of the strengthened/weakened Asian winter/summer monsoon. This indicates that even during a period favorable for the mangrove development, such as the HCO, climatic extremes, such as cold and dry events driven by the strengthened/weakened Asian winter/summer monsoon, can trigger the degradation of mangrove forests.

关键词： Holocene climatic optimum mangrove-derived organic matter degradation of mangrove forests Asian monsoon Qinzhou Bay

Organic carbon isotope and pollen evidence for mangrove development and response to human activity in Guangxi(Southwest China) over the last 140 years

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Acta Oceanologica Sinica 2017年第2期36卷 11-21页

作者： xia peng MENG xianwei LI Zhen FENG Aiping The First Institute of Oceanography State Oceanic Administration Laboratory for Marine Geology Qingdao National Laboratory for Marine Science and Technology School of Earth and Ocean Sciences University of Victoria

Mangrove degradation must reduce carbon sequestration in recent years, thereby aggravating global ***, short-term impacts of human activity on mangrove ecosystems are cause for concern from local governments and scientists. Mangroves sediments can provide detailed records of mangrove species variation in the last one hundred years, based on detailed 210 Pb data. The study traced the history of mangrove development and its response to environmental change over the last 140 years in two mangrove swamps of Guangxi, Southwest China. Average sedimentation rates were calculated to be 0.48 cm/a and 0.56 cm/a in the Yingluo Bay and the Maowei Sea, respectively. Chemical indicators（δ13Corg and C：N） were utilized to trace the contribution of mangrove-derived organic matter（MOM） using a ternary mixing model. Simultaneous use of mangrove pollen can help to supplement some of these limitations in diagenetic/overlap of isotopic signatures. We found that vertical distribution of MOM was consistent with mangrove pollen, which could provide similar information for tracing mangrove ecosystems. Therefore, mangrove development was reconstructed and divided into three stages： flourishing, degradation and re-flourishing/re-degradation period. The significant degradation, found in the period of 1968–1998 and 1907–2007 in the Yingluo Bay and the Maowei Sea, respectively, corresponding to a rapid increase of reclamation area and seawall length, rather than climate change as recorded in the region.

关键词： mangrove development organic carbon isotope pollen human activity Guangxi

Study on the breakup lengths of free round liquid jets

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航空动力学报 2007年第8期22卷 1258-1263页

作者： ZHU Ying WAN Yun-xia HUANG Yong peng Xin-ke School of Jet Propulsion Beijing University of Aeronautics and Astronautics Beijing 100083 China

An experi ment was conducted to measure the breakup lengths of water jets with a high-speed video camera for Weber numbers from0 to about 1.1×*** initial jet diameters are changed from0.3 mmto 1. 0 *** results indicate that at lowjet velocity the breakup lengths of the jets are increased linearly from 0 to a maxi *** the Weber number about 20 the breakup length of the jet reaches its maxi mum value for different initial jet *** based onthe dispersion equationis conducted to study the relationship between the growth rate of the jet surface wave and the maxi mumbreakup *** computations showthat the maxi mumgrowth rate for the axisymmetric surface wave has a turning point at Weber number about 20,and that agrees well with the experi ments.

关键词：高速照相机表面波循环液体喷射分散雾化生长率

Tracking Registration Algorithm for Augmented Reality Based on Template Tracking

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International Journal of Automation and computing 2020年第2期17卷 257-266页

作者： peng-xia Cao Wen-Xin Li Wei-Ping Ma Lanzhou Institute of Physics China Academy of Space TechnologyLanzhou 730000China

Tracking registration is a key issue in augmented reality applications,particularly where there are no artificial identifier placed *** this paper,an efficient markerless tracking registration algorithm which combines the detector and the tracker is presented for the augmented reality *** capture the target images in real scenes as template images,use the random ferns classifier for target detection and solve the problem of reinitialization after tracking registration failures due to changes in ambient lighting or occlusion of *** the target has been successfully detected,the pyramid Lucas-Kanade(LK)optical flow tracker is used to track the detected target in real time to solve the problem of slow *** least median of squares(LMedS)method is used to adaptively calculate the homography matrix,and then the three-dimensional pose is estimated and the virtual object is rendered and *** results demonstrate that the algorithm is more accurate,faster and more robust.

关键词： Tracking registration augmented reality markerless random ferns Lucas-Kanade(LK)optical flow