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天津大学学报（自然科学与工程技术版） 2003年第1期36卷 19-22页

作者：李华郑蕊陈宏颜亮吕卫天津大学电子信息工程学院电视与图像信息研究所天津300072

重点介绍了MPEG 2传送流分析仪的功能原理,采用微软公司的VisualC++6.0版本的程序设计语言进行码流分析和结果显示的软件实现方法及硬件设计方案.所研制的分析仪经实践检验证实其对MPEG 2码流的分析结果正确且用户界面简洁友好.

关键词： MPEG-2 传送流分析仪 PCI总线数字电视码流分析语法分析

应对供应中断风险下消费者恐慌囤货行为:涨价策略与限购策略

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管理工程学报 2025年第2期39卷 118-129页

作者：郑锐王宇鲍丽娜武汉理工大学安全科学与应急管理学院武汉理工大学中国应急管理研究中心浙江大学管理学院

本文研究了零售商应对供应中断风险下消费者恐慌囤货行为的涨价策略与限购策略。研究模型考虑一个垄断零售商在两个订货周期内向市场销售一种生活必需品,第二期的供应中断风险可能导致消费者在第一期发生恐慌囤货。研究基于对消费者恐... 详细信息

本文研究了零售商应对供应中断风险下消费者恐慌囤货行为的涨价策略与限购策略。研究模型考虑一个垄断零售商在两个订货周期内向市场销售一种生活必需品,第二期的供应中断风险可能导致消费者在第一期发生恐慌囤货。研究基于对消费者恐慌囤货决策模型的刻画,分析了消费者恐慌囤货行为如何影响零售商利润以及社会总福利,然后进一步分析了零售商分别在什么条件下应采取涨价策略或限购策略以及这些策略将如何影响社会总福利。研究结果表明:(1)当零售商拥有足够的库存时,一定程度的恐慌囤货可以增加零售商利润和社会总福利;而当恐慌囤货导致零售商严重缺货时,恐慌囤货将损害零售商利润和社会总福利。(2)当零售商需要采取策略应对消费者恐慌囤货行为时,存在一个消费者恐慌强度的阈值,当恐慌强度低于阈值时,零售商应采取涨价策略调节消费者的囤货需求;当恐慌强度高于阈值时,零售商应采取限购策略限制消费者的囤货。(3)零售商不同的应对策略对社会总福利有不同的影响,当恐慌强度非常高时,采取限购策略可以显著改善社会总福利;采取涨价策略可以提高零售商的备货动机,在一定条件下可以改善社会总福利。

关键词：供应链管理供应中断风险恐慌囤货需求管理限购策略

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厦门市学龄儿童龋牙修复状况及其影响因素

牙体牙髓牙周病学杂志 2012年第10期22卷 588-590页

作者：李俊震张旭辉李辉莉苏瑞真厦门市口腔医院福建厦门361003

目的:了解厦门市学龄儿童龋牙的修复状况及其影响因素,为开展学龄儿童龋病防治工作提供科学依据。方法:按照分层随机整群抽样方法选取厦门市城乡各2所小学,共824名患龋儿童为研究对象。调查内容包括口腔检查和问卷(儿童问卷和父母问卷)... 详细信息

目的:了解厦门市学龄儿童龋牙的修复状况及其影响因素,为开展学龄儿童龋病防治工作提供科学依据。方法:按照分层随机整群抽样方法选取厦门市城乡各2所小学,共824名患龋儿童为研究对象。调查内容包括口腔检查和问卷(儿童问卷和父母问卷)调查。按照WHO推荐的龋病流行病学调查方法进行口腔检查,记录各牙龋、失、补状况。所有数据经EpiData 3.0录入后,运用SPSS 13.0进行统计分析。结果:824名患龋学龄儿童龋牙修复率为24.27%,影响学龄儿童龋牙修复的主要因素包括:家庭经济文化水平、口腔检查频率、患儿的恐惧心理、就诊时间和医疗费用等。结论:厦门市学龄儿童龋牙修复率较低,农村学龄儿童龋牙修复率明显低于城市。影响龋牙修复的因素众多,应加强口腔保健知识普及,开展定期口腔检查,对儿童龋牙及早进行修复治疗,以促进学龄儿童口腔健康。

关键词：学龄儿童龋病龋修复率影响因素

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超声造影对酒精注射治疗小肝癌疗效研究

中国现代医学杂志 2008年第11期18卷 1568-1570,1574页

作者：肖际东李瑞珍周平朱文晖中南大学湘雅三医院超声科湖南长沙410013

目的应用超声造影对彩超引导下酒精介入治疗小肝癌疗效进行研究。方法应用彩色超声引导无水酒精注射治疗8例小肝癌,每周1次,1个月后应用超声造影检查。结果所有病例治疗后1个月应用超声造影,其中6例肿块内血流消失,各个时相呈无回声增强... 详细信息

目的应用超声造影对彩超引导下酒精介入治疗小肝癌疗效进行研究。方法应用彩色超声引导无水酒精注射治疗8例小肝癌,每周1次,1个月后应用超声造影检查。结果所有病例治疗后1个月应用超声造影,其中6例肿块内血流消失,各个时相呈无回声增强。2例肿块内血流减少,未灭活部分动脉相高回声增强,门脉相及延迟相低回声增强,灭活部分呈无回声增强。病人治疗后全身情况好转,症状减轻或消失,AFP和肝功能改善,无严重并发症发生。结论超声引导酒精介入治疗对小肝癌的治疗有较好的疗效,安全实用,超声造影有助于判断无水酒精注射治疗的疗效。

关键词：超声造影酒精注射小肝癌

Modular assembly of complex C-alkyl glycoside enabled via cooperative NHC and photoredox catalysis

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Science China Chemistry 2025年

作者： rui-Qiang Jiao Ming li Xi Chen Mei-Ze Xu Tian Ding Xiao-Ping Gong Zhuo-Mei li Xue-Yuan liu Yong-Min liang State Key Laboratory of Applied Organic Chemistry Lanzhou University College of Chemistry and Chemical Engineering Northwest Normal University

C-Alkyl glycosides are found in natural products and are indispensable in drug development programs,owing to their diverse range of medicinal ***-component reactions involving glycosyl radical addition are well documented and proved efficient for the C-alkyl glycosides ***,multicomponent reactions for the rapid and controllable construction of structurally diversified C-alkyl glycosides in a single step remains a significant challenge due to the issues associated with balancing reactivity,compatibility,and ***,we report an NHC and photoredox co-catalyzed three-component method to access complex and valuable C-alkyl *** protocol exhibits broad substrate scope and excellent chemoand ***,nine types of sugars are compatible with this *** addition,the generality of this catalytic strategy was further highlighted by the potential for scalable production,the feasibility of further modifications of the products and its successful application in the late-stage functionalization of pharmaceutical skeletons.

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Activatable chemiluminescence probe based on four-arm PEGconjugated-pyropheophorbide-a for in vivo autofluorescence-free imaging of peroxynitrite

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Science China Chemistry 2025年

作者： Jianmei Ke Lei Ding Ronggui lian Cheng zheng Wenjun li Aixian zheng Yupeng Sun Ming Wu Yongyi Zeng Xiaolong liu Maochun Hong Xiaolong Zhang The United Innovation of Mengchao Hepatobiliary Technology Key Laboratory of Fujian Province Mengchao Hepatobiliary Hospital of Fujian Medical University Ganjiang Innovation Academy Chinese Academy of Sciences School of Rare Earths University of Science and Technology of China College of Chemistry Fuzhou University State Key Laboratory of Structure Chemistry Fujian Institute of Research on the Structure of Matter Chinese Academy of Sciences

Peroxynitrite（ONOO-） is a highly reactive nitrogen species that plays pivotal roles in cell signal transduction and physiological or pathological progresses. However, commonly used ONOO-optical imaging probes are still hampered by high background/autofluorescence（fluorescence probe）, short emission wavelength, or poor selectivity in the case of chemiluminescence. Herein,we report a facile method to prepare an activatable chemiluminescence probe（PPA-PEG） with good biocompatibility and functionality for in vivo autofluorescence-free imaging of ONOO-. The PPA-PEG consists of pyropheophorbide-a（PPA）, a typical deep red photosensitizer that acts as both the recognition and signaling element, and 4-arm poly（ethylene glycol）(4-arm PEG), which improves the biosafety and water solubility of probe. These components can self-assemble into nanoparticles（namely PPA-PEG nanoprobe） in aqueous solution. The PPA-PEG nanoprobe showed an ultra-low chemiluminescence signal before interacting with ONOO-, but exhibited good selectivity, high sensitivity and a fast response toward ONOO-. The PPAPEG was successfully applied to image cellular ONOO-changes, as well as the endogenous ONOO-changes in inflammation models and subcutaneous or orthotopic hepatocellular carcinoma（HCC） tumors models in living mice. In vitro and in vivo studies verified the good detection and imaging capabilities of PPA-PEG for peroxynitrite, demonstrating suitable tissue penetration and a high signal-to-background ratio（SBR）. Thus, our nanoprobe can serve as a valuable activatable chemiluminescence imaging tool for studying important peroxynitrite-related chemical and biological applications.

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Mechanical responses of osteoblastS in hard scaffold subjected direct compression during bone tissue engineering

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Mechanical responses of osteoblastS in hard scaffold subject...

Caching Scheme Based on Power-Law Characteristic in Unstructured P2P Networks

第八届全国生物力学学术会议

作者： ZHANG Chun-qiu~(1,2),ZHANG Xi-zheng~1,GUO Yong~1,li rui-xin~1,zheng Xiao-long~1 (1.Tianjin Institute of Medical Equipment Tianjin 300161,China 2.School of Mechanical Engineering, Tianjin University of Technology,Tianjin 300191,China)

Determining how to apply an appropriately mechanical environment which can improve the quality and function of bone-like construct in vitro is a required problem to be solved for the current development of bone tissue engineering.A specific mechanical force may be a key determinant of tissue development in vitro in bone tissue *** the standpoint of bionics,the mechanical environments applied

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Journal of Southwest Jiaotong University(English Edition) 2009年第3期17卷 177-184页

作者：左翠华李瑞轩卢正鼎 School of Computer Science and Technology Huazhong University of Science and Technology

In order to reduce the traffic load and improve the availability of the shared resources in unstructured P2P networks, a caching scheme combining alternative index and adaptive replication （AIAR） is presented. AIAR uses random walk mechanism to disperse the caching information of resources in the network based on its power-law characteristic, and dynamically adjusts replicas according to the visit frequency on resources and the degree information of peers. Subsequent experimental results show that the proposed AIAR scheme is beneficial to improve the search performance of success rate and respond speed. In addition, compared to some existing caching scheme, AIAR can perform much better in success rate, especially in a dynamic environment.

关键词： P2P (peer-to-peer) Caching scheme Replication Random walk Power law

The compound(E)-2-(3,4-dihydroxystyryl)-3-hydroxy-4H-pyran-4-one alleviates neuroinflammation and cognitive impairment in a mouse model of Alzheimer's disease

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Neural Regeneration Research 2025年第11期20卷 3330-3344页

作者： Xueyan liu Wei Wu Xuejuan li Chengyan Wang Ke Chai Fanru Yuan Huijuan zheng Yuxing Yao Chenlu li Zu-Cheng Ye Daijun Zha Department of Medicinal Chemistry School of PharmacyFujian Medical UniversityFuzhouFujian ProvinceChina Fujian Provincial Key Laboratory of Brain Aging and Neurodegenerative Diseases School of Basic Medical SciencesFujian Medical UniversityFuzhouFujian ProvinceChina Institute of Laboratory Animal Center Fujian Medical UniversityFuzhouFujian ProvinceChina Department of Neurosurgery Neurosurgery Research InstituteThe First Affiliated HospitalFujian Medical UniversityFuzhouFujian ProvinceChina Department of Hyperbaric Oxygen National Regional Medical CenterBinhai Campus of the First Affiliated HospitalFujian Medical UniversityFuzhouFujian ProvinceChina

Previous studies have shown that the compound(E)-2-(3,4-dihydroxystyryl)-3-hydroxy-4H-pyran-4-one(D30),a pyromeconic acid derivative,possesses antioxidant and anti-inflammatory properties,inhibits amyloid-β aggregation,and alleviates scopolamine-induced cognitive impairment,similar to the phase Ⅲ clinical drug *** this study,we established a mouse model of Alzheimer's disease via intracerebroventricular injection of fibrillar amyloid-β to investigate the effect of D30 on fibrillar amyloid-β-induced *** results showed that D30 alleviated fibrillar amyloid-β-induced cognitive impairment,promoted fibrillar amyloid-β clearance from the hippocampus and cortex,suppressed oxidative stress,and inhibited activation of microglia and astrocytes.D30 also reversed the fibrillar amyloid-β-induced loss of dendritic spines and synaptic protein ***,we demonstrated that exogenous fibrillar amyloid-βintroduced by intracerebroventricular injection greatly increased galectin-3 expression levels in the brain,and this increase was blocked by *** the role of D30 in clearing amyloid-β,inhibiting neuroinflammation,protecting synapses,and improving cognition,this study highlights the potential of galectin-3 as a promising treatment target for patients with Alzheimer's disease.

关键词： Alzheimer's disease amyloid-β astrocyte cognitive impairment D30 dendritic spines galectin-3 microglia neuroinflammation neuron

Small modifications of endo-functionalized cavities lead to large changes in molecular interaction in water

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Science China Chemistry 2025年第1期 369-376页

作者： Song-Meng Wang Hao Nian Yan-Fang Wang li-Shuo zheng Yu-Tao zheng Yi-Wei Dong liping Huang Xiaoping Wang Wei Jiang liu-Pan Yang Department of Chemistry Southern University of Science and Technology School of Chemistry and Pharmaceutical Sciences State Key Laboratory for Chemistry and Molecular Engineering of Medicinal ResourcesGuangxi Normal University School of Pharmaceutical Science Hengyang Medical School University of South China

Studying molecular recognition in aqueous environments is crucial for understanding biological processes. Herein, we present a series of N-doped endo-functionalized anthracene-based cavities by introducing inward-directed pyridine units. The subtle modifications can significantly affect the binding properties of these receptors, which is similar to the mutations in biological systems. Combining theoretical calculations and molecular recognition experiments demonstrated that these “mutations” have an impact on the hydrophobicity and charge distribution of the hosts, consequently significantly influencing molecular *** is crucial for understanding the intricate mechanisms of molecular-level interactions in biological receptors.

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