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Engineering polymer nanoparticles using cell membrane coating technology and their application in cancer trea.m.nts:Opportunities and challenges

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Nano materials Science 2022年第4期4卷 295-321页

作者： Kai Guo Nanyang Xiao Yixuan Liu Zhenming Wang Judit Tóth János Gyenis Vijay Kumar thakur Ayako Oyane Quazi T.H.Shubhra Stomatology Hospital of Guangzhou medical University Guangzhou Medical UniversityGuangzhou510140China Department of microbiology The University of ChicagoChicagoIL60637USA Department of Pathology School of Basic Medical SciencesNanjing Medical UniversityNanjing21116China State Key Laboratory of Oral Diseases West China Hospital of StomatologySichuan UniversityChengdu610041China Research Centre for Natural Sciences Institute of Materials and Environmental Chemistry1117BudapestMagyar Tudósok Körútja 2Hungary University of Pannonia Egyetem u.10H-8200VeszprémHungary Nanomaterials Research Institute National Institute of Advanced Industrial Science and Technology(AIST)Tsukuba305-8565Japan School of Engineering University of Petroleum&Energy Studies(UPES)Dehradun 248007India

Nanotechnology has revolutionized cancer drug delivery,and recent research continues to focus on the development of“one-size-fits-all,”i.e.,“all-in-one”delivery *** nanomedicines can address significant shortcomings of conventional therapy,biological barriers remain a challenge in their delivery and accumulation at diseased *** achieve long circulation time,immune evasion,and targeted accumulation,conventional nanocarriers need modifications,e.g.,PEGylation,peptide/aptamer attachment,*** such modification is a biomimetic coating using cell membrane(Cm),which can offer long circulation or targeting,or *** top-down Cm coating process is facile and can provide some advantageous features over surface modification by synthetic ***,an overview is provided on the engineering of Cm camouflaged polymer nanoparticles.A short section on Cm and the development of Cm coating technology has been *** description of the preparation and characterization of Cm camouflaged polymer NPs and their applications in cancer trea.m.nt has been reported.A brief comparison between Cm coating and PEGylation has been *** targeting approaches to achieve tumor-specific delivery of Cm coated NPs have been summarized ***,this review will give the readers a nice picture of Cm coated polymer NPs,along with their opportunities and challenges.

关键词： Cell membrane(Cm) Nanoparticles(NPs) Cancer Camouflage Biomimetic coating Drug delivery

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越南HaNoi市土地利用变化研究

越南HaNoi市土地利用变化研究

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作者：范氏梅（Ph(?)m th(?) mai）重庆交通大学

学位级别：硕士

作为一名越南籍留学生对自己国家更加的了解,所以我选择了越南的首都HaNoi市作为硕士论文的研究区域。HaNoi市是越南的首都,也是经济最发达的城市之一。 HaNoi市现由十郡和五县共计十五个行政单位构成，全市面积为92064.02公顷，占全国... 详细信息

作为一名越南籍留学生对自己国家更加的了解,所以我选择了越南的首都HaNoi市作为硕士论文的研究区域。HaNoi市是越南的首都,也是经济最发达的城市之一。 HaNoi市现由十郡和五县共计十五个行政单位构成，全市面积为92064.02公顷，占全国国土面积的0.28%，本文的研究区是扩建前的HaNoi市。随着HaNoi市经济的高速发展，快速的工业化和城市化进程以及HaNoi市2008年的扩大面积使得HaNoi市成为越南土地利用变化最为显著的城市之一。对于越南HaNoi市的土地利用研究内容和预测越南HaNoi市变化的趋势具有十分重要的意义，可以对土地合理开发、土地利用管理、土地利用预测预报等领域带来良好的经济效益、社会预期效益。本文采用越南资源与环境部的土地利用分类标准，对HaNoi市2000-2005年、2005-2010年和2000-2010年三个阶段的土地利用变化进行研究。论文通过收集的HaNoi市2000、2005、2010年的统计年鉴，2000、2005、2010年行政区划图、地形图、交通图、土地利用图(纸图)，2000、2005、2010年土地利用现状图的1:50000和1:10000的土地利用数据库，数据库存储格式为microStation下的dgn格式。结合单一土地利用动态度模型、综合土地利用动态度模型和转移矩阵法对HaNoi市土地利用转移矩阵进行了分析。运用土地利用程度模型对HaNoi市土地利用变化的程度进行研究。运用马尔科夫预测模型来预测了HaNoi市2020、2030土地利用变化的趋势。并对影响HaNoi市土地利用变化的因素进行了定性分析。论文主要研究结果如下： ⑴HaNoi市土地利用以11种土地类型为主体的格局变化。2000-2010年土地利用数量结构变化表现为：①专用设施用地、居住用地、水产养殖用地、其他非农业用地、水系及专用水面、其他农业用地、坟地和信仰-宗教用地面积增加，分别从2000年的17859.93公顷、11752.84公顷、3043.10公顷、171.69公顷、8209.78公顷、65.56公顷、755.49公顷和155.08公顷增加到2010年的24305.80公顷、13438.03公顷、3485.09公顷、541.22公顷、8444.72公顷、279.04公顷、849.99公顷、177.11公顷;②农业产出用地、林业用地和未利用土地面积减少，分别由2000年的40357.31公顷、6772.94公顷和2920.30公顷减少到2010年的33515.49公顷、5182.42公顷和1845.11公顷;③2000-2010年HaNoi市土地利用综合利用年变化率为0.8246%，土地利用变化较为活跃。 ⑵2000-2005年间，HaNoi市土地利用变化转移主要发生在农业产出用地、林业用地、水产养殖用地、居住用地、专用设施用地、水系及专用水面和未利用地之间。其中，农业产出用地的转出面积最大，为3478.92公顷。其次是林业用地，转出面积为1599.74公顷。转出面积最小的是坟地，仅为18.41公顷。2005-2010年间，HaNoi市土地利用变化转移主要发生在农业产出用地、林业用地、水产养殖用地、居住用地、专用设施用地和未利用地之间。其中，农业产出用地的转出面积最大为5146.91公顷。其次是林业用地，转出面积为249.71公顷。转出面积最小的是信仰-宗教用地，仅为0.07公顷。2000-2010年阶段，HaNoi市土地利用变化转移主要发生在农业产出用地、林业用地、水产养殖用地、居住用地、专用设施用地和未利用地之间。其中，农业产出用地的转出面积最大为8625.83公顷。其次是林业用地，转出面积为1849.45公顷。转出面积最小的是坟地，仅为18.62公顷。 ⑶HaNoi市土地利用程度综合指数总体上较高，2000年为305.63、2005年为312.59、2010年为317.65。土地利用程度综合指数变化较小，说明HaNoi市土地利用程度在逐渐提高，速度比较快。2000-2005年间比2005-2010年间的土地利用程度变化大，△I为6.96，△I为5.06，说明从2000-2010年HaNoi市正加强土地资源开发利用度，土地利用变化较快。 ⑷论文应用马尔科夫预测模型预测了HaNoi市土地利用变化。预测结果表明：HaNoi市未来土地利用格局变化的基本态势仍以农业产出用地、林业用地的持续减少和居住用地、专用设施用地的快速增加为主要特征。2010-2030年的20年间，面积保持增加趋势的几种土地利用类型，专用设施用地的增加面积最大，将达到9294.99公顷。其次是居住用地，增加面积将达到2498.71公顷。此外，水系及专用水面、坟地、水产养殖用地、信仰-宗教用地也将分别增加231.67公顷、120.36公

关键词：越南 HaNoi市 GIS 土地利用马尔科夫

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机械弹簧

机械弹簧

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作者： a.m.·沃尔(a.m. Wahl)

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Cytotoxic Properties on Cervical and Liver Cancer Cells of Two Plant Recipes from Burkina Faso

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Journal of Biosciences and medicines 2024年第6期12卷 216-229页

作者： Estelle Ouédraogo Bagora Bayala théodora.m.houkèdè Zohoncon Samiratou Ouédraogo Olga.m.lanie Lompo Essi Etonam Dovo Jean-marie Compaoré Albert théophane Yonli Jacques Simpore Laboratory of molecular Biology and Genetics (LABIOGENE) Joseph KI-ZERBO University Ouagadougou Burkina Faso Center of Biomolecular Research Pietro Annigoni (CERBA) Ouagadougou Burkina Faso Ecole Normale Suprieure Koudougou Burkina Faso Hspital Saint Camille of Ouagadougou (HOSCO) Ouagadougou Burkina Faso Faculty of Health University Saint Thomas dAquin (USTA) Ouagadougou Burkina Faso Chair Research and Action against Cancer Department of Public Health Training and Research Unit in Health Sciences Joseph KI-ZERBO University Ouagadougou Burkina Faso National Population Health Observatory National Institute of Public Health Ouagadougou Burkina Faso the Department of Epidemiology Biostatistics and Occupational Health School of Population and Global Health Montral Canada Laboratory of Pathological Anatomy and Cytology University Joseph KI-ZERBO Ouagadougou Burkina Faso TIIG LA TIIm Ouagadougou Burkina Faso

Cancer is one of the deadliest diseases in developing countries. In recent years, natural plant-based compounds have been used in the search for drugs to combat numerous diseases, including cancer. In this study, we evaluate the cytotoxic properties of paanfo tiben 1 and paanfo tiben 2, two traditional herbal formulations from Burkina Faso used in the trea.m.nt of cancer in Burkina Faso. To this end, the recipes were infused and freeze-dried. the dry extracts obtained were used to determine total phenolics and flavonoids content, assess antioxidant activity using the DPPH, ABTS and FRAP methods, evaluate anti-infla.m.tory properties by inhibiting 15-LOX, COX 1 and 2, and assess cytotoxic activity on HeLa cervical cancer and HePG2 liver cancer cell lines using the mTT test. the paanfo tiben 1 recipe showed the highest levels of total phenolics and flavonoids, as well as the best antioxidant activities, with IC50 values of 21.020 ± 0.6 µg/ml and 22.94 ± 0.57 µg/ml for DPPH and ABTS, and 165.15 mm EAa.m. dry extract for FRAP. It also exhibited the best cytotoxic activity with IC50 values of 112.02 ± 0.025 µg/ml on HeLa cells and 80.67 ± 6.08 µg/ml on HepG2 cells. On the other hand, paanfo tiben 2 exhibited the best anti-infla.m.tory activities through inhibition of 15-LOX and COX 1, with inhibition percentages at 100 µg/ml of 32.523% and 24.717 % respectively. these results could justify the traditional use of these two recipes by traditional health practitioners in the trea.m.nt of cancer sufferers in Burkina Faso.

关键词： Antioxidant Anti-Infla.m.tory Cytotoxicity Paanfo Tiben Burkina

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A New Explicit Algorithm for Bi-Phasic mixture Flow in mIm

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Journal of Southwest Jiaotong University(English Edition) 2002年第2期10卷 152-160页

作者：柳葆生 Barriere th Gelin J.C Institute of Engineering Science Southwest Jiaotong University Chengdu 610031 China LmARC Université de Franche-Comté 24 Chemin de lépitaphe 25030 Besan on France

metal injection moulding (mIm) is a new technology to manufacture small intricate parts in large quantity. Numerical simulation plays an important role in its development. To predict the specific segregation effect in mIm injection, mixture theory is adopted to model the injection flow by a bi-phasic model. this model conducts to the solution of two-coupled Stokes equations. It is an extremely computational consuming solution in the scope of the traditional algorithms, which induce a serious challenge to cost-effectivity of the mIm simulation. Referred to some methods proposed by Lewis in mono-phasic simulation and the implicit algorithms in mIm simulation, a new explicit algorithm is proposed and realized to perform efficiently this type of bi-phasic flow. Numerically this algorithm is devised to perform the simulation in a fully uncoupled manner except for a global solution of the pressure field in each time step. the physical coupling is taken into account in a sequential pattern by fractional steps.

关键词： metal injection moulding simulation explicit algorithm bi-phasic flow

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Interfacial Reinitiation of Free Radicals Enables the Regeneration of Broken Polymeric Hydrogel Actuators

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CCS Chemistry 2023年第3期5卷 704-717页

作者： Baoyi Wu Huanhuan Lu Yukun Jian Dachuan Zhang Yu Peng Jie Zhuo Xiaoxia Le Jiawei Zhang Patrick théato Tao Chen Key Laboratory of marine materials and Related Technologies Zhejiang Key Laboratory of Marine Materials and Protective TechnologiesNingbo Institute of Materials Technology and EngineeringChinese Academy of SciencesNingbo 315201 School of Chemical Sciences University of Chinese Academy of SciencesBeijing 100049 Soft matter Synthesis Laboratory Institute for Biological InterfacesⅢKarlsruhe Institute of Technology(KIT)D-76344 Eggenstein-Leopoldshafen Institute for Chemical Technology and Polymer Chemistry Karlsruhe Institute of Technology(KIT)D-76131 Karlsruhe

Living organisms,from plants to animals,have inspired and guided the design and fabrication of polymeric hydrogels with biomimetic morphology,shape deformation,and actuation ***,the existing polymeric hydrogels are fragile and vulnerable,which seriously hinders further ***,endowing hydrogels with a biomimetic self-growth property and regenerating the macroscopic shape of hydrogels after they suffer significant damage are highly desirable for the next generation of adaptive biomimetic *** by the tail regeneration of geckos,we herein report an efficient and universal strategy of interfacial diffusion polymerization(IDP),which can regenerate the polymeric layer at a solid–liquid interface,thereby growing new hydrogels on the existing hydrogel *** changing the solvent viscosity and/or monomer type of the hydrogel precursor,diverse new hydrogels have been regenerated to endow the initial hydrogels with additional fluorescent functions and/or actuating *** to the high efficiency and universality of IDP,an injured hydrogel actuator can be repaired,regenerated,and recovered to its initial condition,even after suffering severe damage such as cutting or *** believe that the regeneration strategy of polymeric hydrogels will inspire the design of biomimetic materials and motivate the fabrication of the next generation of soft robots with adaptive and multifunctional properties.

关键词： hydrogels biomimetics interface diffusion polymerization free radicals monitor

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Alteration of Cylindrospermopsin Content of <i>Aphanizomenon ovalisporum</i>(Cyanobacteria, Nostocales) due to Step-Down from Combined Nitrogen to Dinitrogen

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Advances in microbiology 2013年第8期3卷 557-564页

作者： Gábor Vasas Gyula Surányi István Bácsi márta.m.Hamvas Csaba.m.thé Sándor Gonda George Borbely Department of Botany Faculty of Science University of Debrecen Debrecen Hungary Department of Hidrobiology Faculty of Science University of Debrecen Debrecen Hungary

In this study we show that cylindrospermopsin (a cyanotoxin) content of filaments of Aphanizomenon ovalisporum ILC164 depended on growth on combined nitrogen or nitrogen fixation. Our results also demonstrated that the shift down of cyanobacterial filaments from combined nitrogen to dinitrogen fixing condition resulted in a significant decrease of cylindrospermopsin pool size which resumed a growth rate dependent manner as the heterocyst and nitrogenase formation appeared. the current study indicated that alteration of nitrogen metabolism of Aphanizomenon ovalisporum (Forti) induced changes in cyanotoxin (cylindrospermopsin) metabolism. In addition, this is the first report that isolated heterocysts, the differentiated anaerobic cells for nitrogen fixation of cyanobacteria, did not contain cylindrospermopsin.

关键词： Cylindrospermopsin Cyanobacteria Heterocyst Nitrogen Starvation Nitrogenase Cyanotoxin

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Novel All Digital Scheme for Open Loop Fiber Optic Gyroscopes

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Chinese Journal of Lasers 1997年第6期B6卷 39-43页

作者： YANG Yuanhong(the 5th Research Division of Beijing University of Aeronauts & Astronauts,P.O.Box 85, Beijing 100083, China) Beijing Univ of Aeronautics and Astronautics Beijing China

ＮｏｖｅｌＡｌＤｉｇｉｔａｌＳｃｈｅｍｅｆｏｒＯｐｅｎＬｏｏｐＦｉｂｅｒＯｐｔｉｃＧｙｒｏｓｃｏｐｅｓＹＡＮＧＹｕａｎｈｏｎｇ（Ｔｈｅ５ｔｈＲｅｓｅａｒｃｈＤｉｖｉｓｉｏｎｏｆＢｅｉｊｉｎｇＵｎｉｖｅｒｓｉｔｙｏｆＡ... 详细信息

ＮｏｖｅｌＡｌＤｉｇｉｔａｌＳｃｈｅｍｅｆｏｒＯｐｅｎＬｏｏｐＦｉｂｅｒＯｐｔｉｃＧｙｒｏｓｃｏｐｅｓＹＡＮＧＹｕａｎｈｏｎｇ（Ｔｈｅ５ｔｈＲｅｓｅａｒｃｈＤｉｖｉｓｉｏｎｏｆＢｅｉｊｉｎｇＵｎｉｖｅｒｓｉｔｙｏｆＡｅｒｏｎａｕｔｓ＆Ａｓｔｒｏｎａｕ...

关键词： open loop FOG all digital detection all digital processing

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Interleukin-1α, 6 regulate the secretion of vascular endothelial growth factor A, C in pancreatic cancer

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Hepatobiliary & Pancreatic Diseases International 2005年第3期4卷 460-463页

作者： Department of Hepatobiliary Surgery (Tang RF, Zhang FR, Peng L, Wang SX, Xiao Y and Zhang m) and Department of Dermatology (Wang SX), 4th Hospital, Hebei medical University, Shijiazhuang 050011, China Department of Hepatobiliary Surgery 4th Hospital Hebei Medical University Shijiazhuang 050011 China. tangreifeng@***

Vascular endothelial growth factor (VEGF, namely VEGF-A) is an angiogenic polypeptide and VEGF-C is a lymphangiogenic polypeptide that has been implicated in cancer growth, invasion and metastasis. Several cytokines and growth factors play an important part in cancer progression. these cytokines and growth factors are the principal mediators of cancer cells-stromal cell interaction , which is critical for invasion of cancer cells to the surrounding tissues and metastatic dissemination to distant organs. In this study, we studied VEGF-A, C expression in cultured human pancreatic cancer cell lines and whether the presence of VEGF-A, C in the cell lines is regulated by cytokines interleukin-lct (EL-1α), and interleukin-6 (IL-6). mEthODS: We used Northern blot and Western blot methods to analyze expression of the gene and protein of VEGF-A, C in all 6 tested cell lines (ASPC-1, CAPAN-1, mIA-PaCa-2, PANC-1, COLO-357 and T3m4) respectively. To analyze what is the regulator for this VEGF-A, C expression in pancreatic cancer,we used the reverse transcription -polymerase chain reaction (RT-PCR) method to analyze VEGF-A, C expression in cultured human pancreatic cancer cell lines (CAPAN-1 and COLO-357) under the stimulation with IL-1α (10μg/L) or IL-6 (100 μg/L). RESULTS:Northern blot analysis revealed the presence of the 4.1-kb VEGF-a.m.NA transcript and 2.4-kb VEGF-C mRNA transcript in all 6 tested cell lines. Immunoblotting with highly specific anti-VEGF-A, anti-VEGF-C antibody revealed the presence of a.m.lecular weight of 43-kDa VEGF-A protein and 55-kDa VEGF-C protein in all the cell lines. RT-PCR analysis revealed the levels of the VEGF-A and VEGF-C gene were 1-2 fold and a 1-fold increase in the COLO-357 cell line by stimulation with IL-la, however, no effect was found in the CAPAN-1 cell line. the levels of the VEGF-A and VEGF-C gene were 2-5 fold and a 1-fold increase in the CAPAN-1 cell line by stimulation with IL-6, but, no effect was found in the COLO-357 cell li

关键词： pancreatic cancer vascular endothelial growth factor VEGF-C cytokine interleukin-1α interleukin-6

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methionine sources and genotype affect embryonic intestinal development,antioxidants,tight junctions,and growth-related gene expression in chickens

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Animal Nutrition 2024年第1期16卷 218-230页

作者： James K.Lugata Sawadi F.Ndunguru Gebrehaweria K.Reda Xénia E.Ozsváth Eszter Angyal Levente Czeglédi Gabriella Gulyás Renáta Knop János Oláh Zoltán mészár Rita Varga Brigitta Csernus Csaba Szabó Department of Animal Nutrition and Physiology Faculty of Agriculture and Food Sciences and Environmental ManagementUniversity of DebrecenDebrecenHungary Department of Animal Husbandry Faculty of Agriculture and Food Sciences and Environmental ManagementUniversity of DebrecenDebrecenHungary Faculty of Agriculture and Food Sciences and Environmental management Doctoral School of Animal ScienceUniversity of DebrecenDebrecenHungary Institutes for Agricultural Research and Educational Farm University of DebrecenDebrecenHungary Department of Anatomy Histology and EmbryologyFaculty of MedicineUniversity of DebrecenDebrecenHungary Department of Evolutionary Zoology and Human Biology Faculty of Science and TechnologyUniversity of DebrecenDebrecenHungary

methionine(met)is an essential and first limiting amino acid in the poultry diet that plays a significant role in chicken embryonic development and *** present study examined the effect of in ovo injection of DL-met and L-met sources and genotypes on chicken embryonic-intestinal development and *** eggs of the two genotypes,TETRA-SL layer hybrid(TSL)—commercial layer hybrid and Hungarian Partridge colored hen breed(HPC)—a native genotype,were randomly distributed into four trea.m.nts for each *** trea.m.nt groups include the following:1)control non-injected eggs(NoIn);2)saline-injected(SaIn);3)DL-met injected(DLm);and 4)L-met injected(Lm).the in ovo injection was carried out on 17.5 d of embryonic development;after hatching,eight chicks per group were sacrificed,and the jejunum was extracted for *** results showed that both DLm and Lm groups had enhanced intestinal development as evidenced by increased villus width,villus height,and villus area(Pmpared to the *** DLm group had significantly reduced crypt depth,glutathione(GSH)content,glutathione S-transferase 3 alpha(GST3),occludin(OCLN)gene expression and increased villus height to crypt depth ratio in the TSL genotype than the Lm group(Pthe HPC genotype has overexpressed insulin-like growth factor 1(IGF1)gene,tricellulin(mD2),occludin(OCLN),superoxide dismutase 1(SOD1),and GST3 genes than the TSL genotype(Pthese findings showed that in ovo injection of met enhanced intestinal development,and function,with genotypes responding differently under normal *** also influenced the expression of intestinal antioxidants,tight junction,and growth-related genes.

关键词： DL-methionine L-methionine In ovo injection Intestinal development Poultry

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