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Temporal changes in wetland plant communities with decades of cumulative water pollution in two plateau lakes in China's Yunnan Province 被引量:1
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作者 WANG Si-hai WU Chao +3 位作者 XIAO De-rong WANG Juan CHENG Xi-ping GUO Fang-bin 《Journal of Mountain Science》 SCIE CSCD 2017年第7期1350-1357,共8页
Abstract: Wetland plant communities in the plateau lakes of Yunnan Province, China, have decreased significantly over the past decades. To better understand this degradation, we analyzed the processes and characteris... Abstract: Wetland plant communities in the plateau lakes of Yunnan Province, China, have decreased significantly over the past decades. To better understand this degradation, we analyzed the processes and characteristics of changes in wetland plant communities in two of the largest lakes in Yunnan Province, Dianchi and Erhai lakes. We collected records of native and alien plant communities in the two lakes from literature published from the 195os to current period. We calculated plant community types and their area in some historical periods when related data were reported, and analyzed the relationship between chances in nlant communities and water nollution. InDianehi Lake, 12 community types of native plant communities, covering over 80% of the surface in the 195os and 196os, were reduced to four types covering 2.4% by the late 2ooos. Alien plant communities started to appear in the lake in the late 197os, and have since come to cover 4.9% of the lake surface, thereby becoming dominant. In Erhai Lake, 16 community types of native plant communities, covering 47.1% of the lake surface in the late 197os, declined to lo community types, covering 9.3% of the surface, by the late 2ooos. Alien plant communities appeared in the middle 198os, and at present cover 0.7% of the surface area. It was indicated that changes in plant communities were significant related to water eutrophication. The area occupied by native and alien plant communities was, respectively, negatively andpositively related to the content of nutrients in water. This showed lacustrine pollution played an important role in native plant loss and alien plant invasion in the two plateau lakes. 展开更多
关键词 Dianchi Lake Erhai Lake Wetland plantcommunity EUTROPHICATION Alien plant
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荣格“原型”理论内涵再探 被引量:3
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作者 夏秀 《山东社会科学》 2000年第2期107-108,共2页
荣格的“原型”理论对心理学、文学的研究具有重要的价值。它内涵丰富 ,首先是一种反应倾向或领  悟模式 ,是无意识中的一种“形象构成倾向”。其次 ,它又可以形成具体意象 ,可以衍生出丰富多采的形象。处于形象和具体物之间 ,因此具... 荣格的“原型”理论对心理学、文学的研究具有重要的价值。它内涵丰富 ,首先是一种反应倾向或领  悟模式 ,是无意识中的一种“形象构成倾向”。其次 ,它又可以形成具体意象 ,可以衍生出丰富多采的形象。处于形象和具体物之间 ,因此具有中介性 ;它是意识所无法把握的 ,所以具有隐蔽性 ;同时 ,它又与地理因素和历史条件无关 ,存在于从古至今一切人的心理中 ,具有普遍性和永恒性。 展开更多
关键词 荣格 '原型'理论 内涵 反应倾向 形象构成倾向
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Light-Induced Hofstadter's Butterfly Spectrum in Optical Lattices
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作者 HOU Jing-Min 《Communications in Theoretical Physics》 SCIE CAS CSCD 2009年第3期441-444,共4页
We propose a scheme to create an effective magnetic field, which can be perceived by cold neutral atoms in a two-dimensional optical lattice, with a laser field with a space-dependent phase and a conventional laser fi... We propose a scheme to create an effective magnetic field, which can be perceived by cold neutral atoms in a two-dimensional optical lattice, with a laser field with a space-dependent phase and a conventional laser field acting on A-type three-level atoms. When the dimensionless parameter a, being the ratio of flux through a lattice cell to one flux quantum, is rational, the energy spectrum shows a fractal band structure, which is so-called Hofstadter's butterfly. 展开更多
关键词 optical lattices cold atoms Hofstadter's butterfly
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电影中的怪物——魅惑人心的“原型” 被引量:2
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作者 王珺 《电影评介》 北大核心 2008年第6期12-12,共1页
怪物,一直是电影所热衷表现的对象之一。根据荣格的"原型"理论,怪物是作为一种集体无意识的具象活跃在人类舞台上的。在好莱坞电影中,这种"原型"则化身为摄人心魄的百变魅影,定居在银幕的一角警示着人类。
关键词 怪物 '原型' 异化
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“妈祖”原型与许地山小说的关系 被引量:4
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作者 张永 《江苏社会科学》 CSSCI 北大核心 2003年第1期124-129,共6页
本文从民俗学角度阐释妈祖文化对许地山创作的影响。妈祖从一个真实普通的女性演化为特异的神灵,并在长期流传中浸染上宗教色彩。小说中人物刻画、意象营造和情节建构都与妈祖原型叙事存在着同构现象。
关键词 '妈祖'原型 许地山 小说 民俗学 创作 宗教色彩 民间故事 '妈祖'文化
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旷野中奏响的生命狂欢曲——《红高粱》中“红色”原型的解读 被引量:3
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作者 李静 《山西广播电视大学学报》 2003年第3期97-98,共2页
在《红高粱》这部小说中 ,莫言用他优美的笔调为人们奏响了一曲荡气回肠的生命乐章。现从“红色”原型批评的角度对红高粱世界中呈现出的“生的伟大”“死的美丽”进行全面解释 。
关键词 '红色'原型 红高粱 生命意识 死亡意识 精神家园
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Revealing Photoinduced Charge Transfer Mechanism of SnO2/BiOBr SScheme Heterostructure for CO_(2)Photoreduction
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作者 Yuejiao An Wenxuan Liu +2 位作者 Yanfeng Zhang Jianjun Zhang Zhansheng Lu 《物理化学学报》 SCIE CAS CSCD 北大核心 2024年第12期15-16,共2页
S-scheme heterojunctions can preserve strong redox capacity on the basis of achieving spatial separation of photogenerated carriers.Therefore,a deep comprehension of the photoinduced charge transfer dynamics in S-sche... S-scheme heterojunctions can preserve strong redox capacity on the basis of achieving spatial separation of photogenerated carriers.Therefore,a deep comprehension of the photoinduced charge transfer dynamics in S-scheme heterostructures is vital to enhancing photocatalytic properties.Herein,SnO_(2)/BiOBr S-scheme heterojunctions with tight contact are fabricated with in situ hydrothermal method.The optimal SnO_(2)/BiOBr exhibits excellent photocatalytic performance for CO_(2)reduction,with yields of CO and CH4 of 345.7 and 6.7μmol∙g^(–1)∙h^(–1),which are 5.6 and 3.7 times higher than those of the original BiOBr.The photoinduced charge transfer mechanism and dynamics of SnO_(2)/BiOBr S-scheme heterostructure are characterized by in situ X-ray photoelectron spectrum(XPS)and femtosecond transient absorption spectroscopy(fs-TA).A new fitted lifetime of photogenerated carriers are observed,which could be attributed to interfacial electron transfer of S-scheme heterojunction,further illustrating an ultrafast transfer channel for photoelectrons from SnO_(2)conduction band to BiOBr valence band.As a result,the powerful reduced electrons in BiOBr conduction band and the powerful oxidation holes in SnO_(2)valence band are retained.This work provides profound comprehension of photoinduced charge transfer mechanism of S-scheme heterojunction. 展开更多
关键词 SnO_(2)/BiOBr CO_(2)photoreduction S-scheme heterojunction fs-TA in situ XPS
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Photocatalytic CO_(2)Reduction by Modified g-C_(3)N_(4)
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作者 Xuejiao Wang Suiying Dong +2 位作者 Kezhen Qi Vadim Popkov Xianglin Xiang 《物理化学学报》 SCIE CAS CSCD 北大核心 2024年第12期7-8,共2页
The use of carbon-based fuels causes a significant increase in CO_(2)emissions,posing a serious threat to the environment.This review explores the potential application of graphitic carbon nitride(g-C_(3)N_(4))in phot... The use of carbon-based fuels causes a significant increase in CO_(2)emissions,posing a serious threat to the environment.This review explores the potential application of graphitic carbon nitride(g-C_(3)N_(4))in photocatalytic CO_(2)reduction as a strategy to mitigate global warming.The effectiveness of g-C_(3)N_(4)(gCN)in this process is hindered by several factors,including rapid exciton recombination,limited solar light absorption,and a lack of active sites for conducting the reduction.To address these challenges,various amendment techniques have been executed,such as adjusting the morphology of g-C_(3)N_(4),doping it with different atoms,and forming heterojunctions with other semiconductors.This review highlights the role of S-scheme heterojunctions in expanding the photocatalytic activity of g-C_(3)N_(4)and emphasizes that,despite its potential as a photocatalyst for CO_(2)reduction,further research and innovation are essential to overcome its current limitations. 展开更多
关键词 g-C_(3)N_(4) PHOTOCATALYSIS CO_(2)reduction Modification S-scheme heterojunction
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Design and Implementation of an Open Network Security Management Platform 被引量:2
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作者 曹元大 王勇 《Journal of Beijing Institute of Technology》 EI CAS 2002年第3期316-320,共5页
In order to manage all kinds of network security devices and software systems efficiently, and make them collaborate with each other, the model for an open network security management platform is presented. The feasib... In order to manage all kinds of network security devices and software systems efficiently, and make them collaborate with each other, the model for an open network security management platform is presented. The feasibility and key implementing technology of the model are expatiated. A prototype system is implemented to validate it. 展开更多
关键词 network security management open platform XML RPC SNMP
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Efficient channelized technology based on filter banks 被引量:1
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作者 张迪 韩铮 张立萍 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2016年第3期261-265,共5页
With the appearance of novel radar signal with low intercept probability, the bandwidth of radar receiver is wider and wider. Wideband digital receiver becomes a research hotspot in the field of communication... With the appearance of novel radar signal with low intercept probability, the bandwidth of radar receiver is wider and wider. Wideband digital receiver becomes a research hotspot in the field of communication, radar and electronic reconnaissance, etc. As one of wideband digital receiver systems, digital channelized receiver has become a research emphasis due to the characteristics of full probability receiving and processing multiple signals. Digital channelized technology and signal sampling theory are deeply studied and an efficient channelized model is derived based on filter banks. The correctness of the model is verified by computer simulation The model has less computation compared with the traditional model, which is suitable for engineering application 展开更多
关键词 filter banks efficient channelized technology band-pass sampling prototype filter
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Recovery of cobalt from converter slag of Chambishi Copper Smelter using reduction smelting process 被引量:6
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作者 翟秀静 李乃军 +2 位作者 张旭 符岩 姜澜 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第9期2117-2121,共5页
The reduction smelting process for cobalt recovery from converter slag of the Chambishi Copper Smelter in Zambia was studied. The effects of reducing agent dosage, smelting temperature and time and the addition of sla... The reduction smelting process for cobalt recovery from converter slag of the Chambishi Copper Smelter in Zambia was studied. The effects of reducing agent dosage, smelting temperature and time and the addition of slag modifiers (CaO and TiO2) were investigated. In addition, the depleted slag and cobalt-bearing alloy were characterized by X-ray diffraction, scanning electron microscopy and energy dispersive spectroscopy. Under the determined conditions, 94.02% Co, 95.76% Cu and less than 18% Fe in the converter slag were recovered. It was found that the main phases of depleted slag were fayalite and hercynite; and the cobalt-bearing alloy mainly contained metallic copper, Fe-Co-Cu alloys and a small amount of sulfide. 展开更多
关键词 converter slag cobalt recovery reduction smelting slag modifier cobalt-bearing alloy
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Detecting Vegetation Fractional Coverage of Typical Steppe in Northern China Based on Multi-scale Remotely Sensed Data 被引量:15
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作者 李晓兵 陈云浩 +1 位作者 史培军 陈晋 《Acta Botanica Sinica》 CSCD 2003年第10期1146-1156,共11页
One of the study objectives of global change is land use/cover change (LUCC) by using multiscale remotely sensed data on global and regional scale. In this paper, field sample, digital camera, Landsat-ETM+ (ETM+, Enha... One of the study objectives of global change is land use/cover change (LUCC) by using multiscale remotely sensed data on global and regional scale. In this paper, field sample, digital camera, Landsat-ETM+ (ETM+, Enhanced Thematic Mapper) image and the National Oceanic and Atmospheric Administration/the advanced very high resolution radiometer (NOAA/AVHRR) image were integrated to detect, simulate and analyze the vegetation fractional coverage of typical steppe in northern China. The results show: (1) Vegetation fractional coverage measured by digital camera is more precise than results measured by other methods. It can be used to validate other measuring results. (2) Vegetation fractional coverage measured by 1 m 2 field sample change fluctuantly for different observers and for different sample areas. In this experiment, the coverage is generally high compared with the result measured by digital camera, and the average absolute error is 9.92%, but two groups measure results, correlation coefficient r(2) = 0.89. (3) Three kinds of methods using remotely sensed data were adopted to simulate the vegetation fractional coverage. Average absolute errors of the vegetation fractional coverage, measured by ETM+ and NOAA, are respectively 7.03% and 7.83% compared with the result measured by digital camera. When NOAA pixel was decomposed by ETM+ pixels after geometrical registry, the average absolute errors measured by this method is 5.68% compared with the digital camera result. Correction coefficients of three results with digital camera result r(2) are respectively 0.78, 0.61 and 0.76. (4) The result of statistic model established by NOAA-NDVI (NDVI, Normalized Difference Vegetation Index) and the vegetation fractional coverage measured by digital camera show lower precision (r(2) = 0.65) than the result of statistic model established by ETM+-NDVI and digital camera coverage then converted to NOAA image (r(2) = 0.80). Pixel decomposability method improves the precision of measuring the vegetation fractional coverage on a large scale. This is a significant practice on scaling by using remotely sensed data. Integrated application of multi-scale remotely sensed data in earth observation will be an important approach to promoting measuring precision of ecological parameters. 展开更多
关键词 multi-scale remote sensing typical steppe vegetation fractional coverage
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Memetic analysis on the prototype theory 被引量:1
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作者 邹春玲 苏秀云 《Sino-US English Teaching》 2007年第8期36-38,共3页
Meme, which was proposed by Dawkins first, is considered as one of the necessary elements which can explain the emergence and extinction of the language. Thus, some linguists are engaged in perfecting the linguistic t... Meme, which was proposed by Dawkins first, is considered as one of the necessary elements which can explain the emergence and extinction of the language. Thus, some linguists are engaged in perfecting the linguistic theories from the completely new aspect based on the new interface -- meme. This paper has briefly introduced the preliminary achievements in the memetics research. In terms of the memetics it gives a new analysis on the prototype theory, one of the important theories in the cognitive linguistics, and explores that meme is the cognitive root of the prototype theory. Besides, employing the memetics the paper has explained the cognitive characteristics of the prototype theory. The authors hold the prototype is one kind of memes, while the non-prototype or peripheral member of this prototype is the memetine of this meme. 展开更多
关键词 MEME orototvoe theorv memetine
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Highly selective supported gold catalyst for CO-driven reduction of furfural in aqueous media 被引量:1
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作者 董静 朱明明 +4 位作者 张高硕 刘永梅 曹勇 刘苏 王仰东 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2016年第10期1669-1675,共7页
The reductive transformation of furfural (FAL) into furfuryl alcohol (FOL) is an attractive route for the use of renewable bio‐sources but it suffers from the heavy use of H2. We describe here a highly efficient ... The reductive transformation of furfural (FAL) into furfuryl alcohol (FOL) is an attractive route for the use of renewable bio‐sources but it suffers from the heavy use of H2. We describe here a highly efficient reduction protocol for converting aqueous FAL to FOL. A single phase rutile TiO2 support with a gold catalyst (Au/TiO2‐R) that used CO/H2O as the hydrogen source catalyze this reduction efficiently under mild conditions. By eliminating the consumption of fossil fuel‐derived H2, our pro‐cess has the benefit afforded by using CO as a convenient and cost competitive reducing reagent. 展开更多
关键词 Furfural Reduction Supported gold catalyst Carbon monoxide AQUEOUS
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A New Genus (Protosciadopityoxylon gen .nov .) of Early Cretaceous Fossil Wood from Liaoning ,China 被引量:2
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作者 张武 郑少林 丁秋红 《Acta Botanica Sinica》 CSCD 1999年第12期1312-1316,共5页
Anewgenus (Protosciadopityoxylongennov .)ofEarlyCretaceousfossilwoodreportedinthepre sentpaperwasdiscoveredfromLiaoningProvince ,China ,andisnamedasanewspecies :Protosciado pityoxylonliaoningensegen .etsp .nov .It... Anewgenus (Protosciadopityoxylongennov .)ofEarlyCretaceousfossilwoodreportedinthepre sentpaperwasdiscoveredfromLiaoningProvince ,China ,andisnamedasanewspecies :Protosciado pityoxylonliaoningensegen .etsp .nov .Itisdescribedhereandthisgenericname ,adoptedbytheauthors ,is employedforfossilwoodthatisbelievedtobenearlyrelatedtotherecentgenusSciadopitysandthefossil genusSciadopityoxylon .ThenewgenusbearssomesimilaritiestoProtophyllocladoxylon ,Protocircoporoxylon andXenoxylonindifferentgeologicalages ,butitdiffersfromtheminthetypesofcross_fieldpitting . 展开更多
关键词 LIAONING EarlyCretaceous Fossilwood Protosciadopityoxylon (gen .nov .)
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Pilot Study of Molecular Mechanism on Vasculogenic Mimicry in Bi-directional Differentiated Malignant Tumors 被引量:2
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作者 孙保存 张诗武 +2 位作者 赵秀兰 张丹芳 郝希山 《The Chinese-German Journal of Clinical Oncology》 CAS 2005年第1期50-52,68,共4页
Objective: To investigate the role of collagen IV and PAS positive substancesecreted by tumor cells in vasculogenic mimicry (VM) and the effects of VM on tumor cells expressingVEGF. Methods: 158 cases of bi-direction ... Objective: To investigate the role of collagen IV and PAS positive substancesecreted by tumor cells in vasculogenic mimicry (VM) and the effects of VM on tumor cells expressingVEGF. Methods: 158 cases of bi-direction differential malignant tumor specimens withparaffin-embedded were enrolled into our study and made tissue microarray which were dual-stainedwith CD31-PAS and stained with collagen IV. The difference of the areas and distribution withpattern surrounded by between CD31 and PAS positive respectively were identified via grid-counting,as well as the difference of VEGF expression with VE absent and present. Results: The basementmembrane of VM was both PAS and collagen IV positive. VEGF expression in the bi-directiondifferential malignant tumor was higher VM-absent than VM-present and the difference wasstatistically significance in malignant melanoma and alveolar rhabdomyosarcoma (P 【 0.05).Conclusion: PAS positive substance and collagen IV compose the wall of VE and VE could provide theoxygen and nutrition for tumor growth and progression. 展开更多
关键词 bi-direction differential malignant tumor vasculogenic mimicry dual-staining tissue microarray
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Gelled Ionic Liquid/PMMA Polymer Electrolyte Prepared by Radical Polymerization 被引量:1
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作者 李丽波 杨硕 +1 位作者 李捷斯 国绍文 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2014年第4期485-490,J0002,共7页
The gel polymer electrolyte containing N-propyl, methylpyrrolidinium bis((trifiuoromethyl) sulfonyl)imide (PYR13TFSI) with better performance is prepared by radical polymerization method. The interface status be... The gel polymer electrolyte containing N-propyl, methylpyrrolidinium bis((trifiuoromethyl) sulfonyl)imide (PYR13TFSI) with better performance is prepared by radical polymerization method. The interface status between the LiFePO4 electrode and the electrolyte is characterized by a scanning electron microscope and X-ray photoelectron spectroscopy (XPS). There is a layer of membrane on the gel electrolyte and perfect shell membranes on the surface of active LiFePO4 cluster, on the other hand, N and S photoelectron signals are observed in XPS spectra after charge-discharge cycles. The results show that the ionic liquids and unpolymerized methyl methacrylate incorporate into the electrode surface and form the SEI membrane with Li ion and electrons while the gel electrolyte contacts with the electrode. The formation process of the SEI membrane needs at least three cycles, the discharge capacity increases as the SEI membrane becomes sufficiently thick, which blocks further electron transfer, and the system may approach steady state. The performance of cell with ionic liquid gel polymer electrolyte is measured at different rate. The cells retain 132 mAh/g at 0.2 C, 128 mAh/g at 0.5 C, and 120 mAh/g at 1.0 C after 30 cycles with charge-discharge efficiency of ca. 98% at every rate. 展开更多
关键词 Radical polymerization Gelled ELECTROLYTE ELECTROCHEMISTRY
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Cavitary Pulmonary Metastases: CT Features and Their Correlation with the Pathology of the Primary Malignancy 被引量:1
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作者 于小平 王平 梁赵玉 《The Chinese-German Journal of Clinical Oncology》 CAS 2004年第1期29-33,66,共6页
Objective: To study CT features of cavitary pulmonary metastases and to investigate the pos- sible relationship between CT features and the pathology of the primary lesions. Methods: CT ?ndings o... Objective: To study CT features of cavitary pulmonary metastases and to investigate the pos- sible relationship between CT features and the pathology of the primary lesions. Methods: CT ?ndings of 131 cavitary metastatic nodules in 40 patients with pathologically-proved pulmonary metastases were retrospectively analyzed. A comparison between CT signs and the pathologic types of the primary tumors was made. Results: Cavitary metastases and multiple solid nodules coexisted in all patients. Cavitary metastases presented as bubble (n=41), irregular (n=33), cystic (n=26) or small circular (n=31) cavities, with even (n=61) or uneven (n=70) thickness of the cavity wall. Of 131 cavitary nodules, diameter less than 15 mm was seen in 44, between 15–25 mm in 66, 25–40 mm in 17 and larger than 40 mm in 4 respectively. And the wall thickness of the cavity below 4 mm, between 4–15 mm and over 15 mm was respectively seen in 69, 44 and 18 metastatic nodules. Cavitary pulmonary metastases mainly occurred in patients whose primary malignancy was squamous cell carcinoma (n=13) or adenocarcinoma (n=22). Both squamous cell carcinoma and adenocarcinoma had its own CT characteristics. The occurrence of cavity bore no relationship to its site in the lung. Conclusion: Cavitary pulmonary metastases carries certain CT features and its occurrence is related to the pathologic type of the primary malignancy. 展开更多
关键词 lung neoplasm metastatic tomography X-ray computed PATHOLOGY
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Vascular Channel Formation by Osteosarcoma Cells in Vitro: Vasculogenic Mimicry 被引量:2
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作者 梅炯 贾永伟 蔡宣松 《The Chinese-German Journal of Clinical Oncology》 CAS 2003年第4期237-239,253,共4页
Objective: To observe whether there is evidence for vascular channel formation by osteosarcoma cellsin vitro and to illustrate mechanism of vasculogenic mimicry in osteosarcoma.Methods: Osteosarcoma cell lines (U-2OS)... Objective: To observe whether there is evidence for vascular channel formation by osteosarcoma cellsin vitro and to illustrate mechanism of vasculogenic mimicry in osteosarcoma.Methods: Osteosarcoma cell lines (U-2OS) were tested for their ability to form tubular networks in three-dimensional culture containing type I collagen. The structures of the tubular networks were observed under a phase contrast microscope and an electron microscope.Results: Observation under light microscopy and electron microscopy showed that high aggressive osteosarcoma cells line (U-2OS) formed networks containing channels when grown in three-dimensional culture containing type I collagen in the absence of endothelial cells or fibroblasts.Conclusion: These observations strongly suggest that aggressive osteosarcoma cells may generate vascular channels that facilitate tumor perfusion independent of tumor angiogenesis and have the ability of vasculogenic mimicry. Key words osteosarcoma cells line - vasculogenesis mimicry - angiogenesis - 3-dimensional cultures This study was supported in part by the National Natural Sciences Foundation of China (No. 30271314). 展开更多
关键词 osteosarcoma cells line vasculogenesis mimicry ANGIOGENESIS 3-dimensional cultures
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Simulation study on non-linear effects of initial melt temperatures on microstructures during solidification process of liquid Mg_7Zn_3 alloy 被引量:3
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作者 刘让苏 梁永超 +5 位作者 刘海蓉 郑乃超 莫云飞 侯兆阳 周丽丽 彭平 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2013年第4期1052-1060,共9页
The non-linear effects of different initial melt temperatures on the microstructure evolution during the solidification process of liquid Mg7Zn3 alloys were investigated by molecular dynamics simulation, The microstru... The non-linear effects of different initial melt temperatures on the microstructure evolution during the solidification process of liquid Mg7Zn3 alloys were investigated by molecular dynamics simulation, The microstructure transformation mechanisms were analyzed by several methods. The system was found to be solidified into amorphous structures from different initial melt temperatures at the same cooling rate of 1×10^12 K/s, and the 1551 bond-type and the icosahedron basic cluster (12 0 12 0 ) played a key role in the microstructure transition. Different initial melt temperatures had significant effects on the final microstructures. These effects only can be clearly observed below the glass transition temperature Tg; and these effects are non-linearly related to the initial melt temperatures, and fluctuated in a certain range. However, the changes of the average atomic energy of the systems are still linearly related with the initial melt temperatures, namely, the higher the initial melt temperature is, the more stable the amorphous structure is and the stronger the glass forming ability will be. 展开更多
关键词 liquid Mg-Zn alloy initial melt temperature microstructure evolution molecular dynamics simulation cluster-typeindex method
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