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The neutrophil–osteogenic cell axis promotes bone destruction in periodontitis
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作者 Yutaro Ando Masayuki Tsukasaki +12 位作者 Nam Cong-Nhat Huynh Shizao Zang Minglu Yan Ryunosuke Muro Kazutaka Nakamura Masatsugu Komagamine Noriko Komatsu Kazuo Okamoto Kenta Nakano Tadashi Okamura Akira Yamaguchi Kazuyuki Ishihara Hiroshi Takayanagi 《International Journal of Oral Science》 SCIE CAS CSCD 2024年第1期154-162,共9页
The immune-stromal cell interactions play a key role in health and diseases. In periodontitis, the most prevalent infectious disease in humans, immune cells accumulate in the oral mucosa and promote bone destruction b... The immune-stromal cell interactions play a key role in health and diseases. In periodontitis, the most prevalent infectious disease in humans, immune cells accumulate in the oral mucosa and promote bone destruction by inducing receptor activator of nuclear factor-κB ligand (RANKL) expression in osteogenic cells such as osteoblasts and periodontal ligament cells. However, the detailed mechanism underlying immune–bone cell interactions in periodontitis is not fully understood. Here, we performed single-cell RNAsequencing analysis on mouse periodontal lesions and showed that neutrophil–osteogenic cell crosstalk is involved in periodontitis-induced bone loss. The periodontal lesions displayed marked infiltration of neutrophils, and in silico analyses suggested that the neutrophils interacted with osteogenic cells through cytokine production. Among the cytokines expressed in the periodontal neutrophils, oncostatin M (OSM) potently induced RANKL expression in the primary osteoblasts, and deletion of the OSM receptor in osteogenic cells significantly ameliorated periodontitis-induced bone loss. Epigenomic data analyses identified the OSM-regulated RANKL enhancer region in osteogenic cells, and mice lacking this enhancer showed decreased periodontal bone loss while maintaining physiological bone metabolism. These findings shed light on the role of neutrophils in bone regulation during bacterial infection, highlighting the novel mechanism underlying osteoimmune crosstalk. 展开更多
关键词 period NEUTROPHIL destruction
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Gold mineralization in Jiaodong Peninsula and destruction of North China Craton:Insights from Mesozoic granite 被引量:1
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作者 WANG Bin ZHOU Jianbo +8 位作者 DING Zhengjiang ZHAO Tiqun SONG Mingchun BAO Zhongyi LYU Junyang XU Shaohui YAN Chunming LIU Xiangdong LIU Jialiang 《Global Geology》 2023年第2期98-113,共16页
Large-scale tectonic magmatism and extensive gold mineralization have occurred in the eastern North China Craton(NCC)(Jiaodong and Liaodong peninsulas)since Mesozoic,which indicated that the region experienced decrato... Large-scale tectonic magmatism and extensive gold mineralization have occurred in the eastern North China Craton(NCC)(Jiaodong and Liaodong peninsulas)since Mesozoic,which indicated that the region experienced decratonization process.The genesis type of granites evolved from S-type to I-type and A-type during Late Jurassic to Early Cretaceous,and thus reflects the evolution of geodynamics in the Late Mesozoic,indicating the varied subduction process of the Paleo-Pacific Plate(PPP)and the craton destruction.The evolution of geochemical features shows that the mantle beneath the Jiaodong Peninsula evolved from EM-II in Jurassic to EM-I in Early Cretaceous,demonstrating that the mantle switched from enriched to depleted.The gold of decratonic gold deposits in Jiaodong Peninsula mainly comes from the lithospheric mantle domains metasomatized by fluids derived from the metamorphism and dehydration of the subducted slab in the mantle transition zone.The rapid decomposition of minerals leads to the concentrated release of ore-forming fluids,and this process leads to the explosive gold mineralization during the craton destruction.Extensive magmatic uplift and extensional structures,triggered by the craton destruction in Early Cretaceous formed the extensional tectonic system,providing space for the decratonic gold deposits in Jiaodong Peninsula. 展开更多
关键词 Jiaodong Peninsula Mesozoic granite craton destruction decratonic gold deposit extensional structure
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Influence of vacuoles with gas–liquid inclusions on the thermobaric destruction conditions of natural quartz under dynamic heating in an RF-TICP torch system
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作者 苗龙 聂明卿 +7 位作者 Yuri Mihailovich GRISHIN 王晓宇 朱政羲 宋家辉 梁福文 何梓豪 田丰 王宁飞 《Plasma Science and Technology》 SCIE EI CAS CSCD 2023年第4期138-147,共10页
In the present work,the turbulent mixing process of a polydisperse quartz particle flow with a plasma stream generated by a radio-frequency(RF)inductively coupled plasma torch was numerically studied.The thermobaric s... In the present work,the turbulent mixing process of a polydisperse quartz particle flow with a plasma stream generated by a radio-frequency(RF)inductively coupled plasma torch was numerically studied.The thermobaric stress in the quartz particles under dynamic heating in a heterogeneous plasma flow was determined by a two-stage approximation approach.The effect of the presence of vacuoles in natural quartz on the particle thermobaric destruction conditions was studied.It was found that the equivalent thermal and baric stresses in quartz particles may significantly increase in the presence of vacuoles within a small gas volume fraction.The influence of the regime and energetic working conditions of an RF inductively coupled plasma torch system on the particle thermobaric destruction conditions was examined,and a recommendation was given to promote the degree of thermobaric destruction of quartz particles,which is of substantial importance for improving the overall enrichment efficiency of quartz concentrates. 展开更多
关键词 high purity quartz dynamic heating vacuole with gas–liquid inclusions thermobaric destruction radio-frequency inductively coupled plasma torch
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Airblast evolution initiated by Wangjiayan landslides in the M_(s)8.0 Wenchuan earthquake and its destructive capacity analysis
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作者 Yu-feng Wang Qian-gong Cheng Qi Zhu 《China Geology》 CAS CSCD 2024年第2期237-247,共11页
Airblasts,as one common phenomenon accompanied by rapid movements of landslides or rock/snow avalanches,commonly result in catastrophic damages and are attracting more and more scientific attention.To quantitatively a... Airblasts,as one common phenomenon accompanied by rapid movements of landslides or rock/snow avalanches,commonly result in catastrophic damages and are attracting more and more scientific attention.To quantitatively analyze the intensity of airblast initiated by landslides,the Wangjiayan landslide,occurred in the Wenchuan earthquake,is selected here with the landslide propagation and airblast evolution being studied using FLUENT by introducing the Voellmy rheological law.The results reveal that:(1)For the Wangjiayan landslide,its whole travelling duration is only 12 s with its maximum velocity reaching 36 m/s at t=10 s;(2)corresponding to the landslide propagation,the maximum velocity,28 m/s,of the airblast initiated by the landslide also appears at t=10 s with its maximum pressure reaching594.8 Pa,which is equivalent to violent storm;(3)under the attack of airblast,the load suffered by buildings in the airblast zone increases to 1300 Pa at t=9.4 s and sharply decreased to-7000 Pa as the rapid decrease of the velocity of the sliding mass at t=10 s,which is seriously unfavorable for buildings and might be the key reason for the destructive collapse of buildings in the airblast zone of the Wangjiayan landslide. 展开更多
关键词 LANDSLIDE Voellmy rheological law 3D FLUENT simulation Airblast Intensity Building destructive collapse Wenchuan earthquake Geological hazards survey engineering
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The Al_(2)O_(3)and Mn/Al_(2)O_(3)sorbents highly utilized in destructive sorption of NF_(3)
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作者 Yanfei Pan Hejian Li +1 位作者 Li Zheng Xiufeng Xu 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第1期54-62,共9页
NF_(3)is commonly used as an etching and cleaning gas in semiconductor industry,however it is a strongly greenhouse gas.Therefore,the destruction of disposal NF_(3)is an urgent task to migrate the greenhouse effect.Am... NF_(3)is commonly used as an etching and cleaning gas in semiconductor industry,however it is a strongly greenhouse gas.Therefore,the destruction of disposal NF_(3)is an urgent task to migrate the greenhouse effect.Among the technologies for NF_(3)abatement,the destructive sorption of NF_(3)over metal oxides sorbents is an effective way.Thus,the search for a highly reactive and utilized sorbent for NF_(3)destruction is in great demand.In this work,AlOOH supported on carbon-sphere(AlOOH/CS)as precursors were synthesized hydrothermally and heat-treated to prepare the Al_(2)O_(3)sorbents.The influence of AlOOH/CS hydrothermal temperatures on the reactivity of derived Al_(2)O_(3)sorbents for NF_(3)destruction was investigated,and it is shown that the Al2O3 from AlOOH/CS hydro-thermalized at 120℃is superior to others.Subsequently,the optimized Al_(2)O_(3)was covered by Mn(OH)x to prepare Mn/Al_(2)O_(3)sorbents via changing hydrothermal temperatures and Mn loadings.The results show that the Mn/Al_(2)O_(3)sorbents are more utilized than bare Al_(2)O_(3)in NF_(3)destructive sorption due to the promotional effect of Mn_(2)O_(3)as surface layer on the fluorination of Al_(2)O_(3)as substrate,especially the optimal 5%Mn/Al2O3(160℃)exhibits a utilization percentage as high as 90.4%,and remarkably exceeds all the sorbents reported so far.These findings are beneficial to develop more efficient sorbents for the destruction of NF_(3). 展开更多
关键词 Greenhouse gas NF_(3)destructive sorption Sorbents Al_(2)O_(3) Mn/Al_(2)O_(3) REACTIVITY
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Theoretical Study on Destruction Mechanism of 2,3,7,8-TCDD by O3 and NO3 被引量:2
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作者 王智化 温正城 +2 位作者 徐江荣 周俊虎 岑可法 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2010年第3期303-309,I0001,共8页
In order to improve the destruction efficiency of dioxins and also for developing new dioxin control technology, the destruction mechanisms of 2,3,7,8-tetrachlorodihenzo-p-dioxin (2,3,7,8-TCDD) by O3 and NO3, were i... In order to improve the destruction efficiency of dioxins and also for developing new dioxin control technology, the destruction mechanisms of 2,3,7,8-tetrachlorodihenzo-p-dioxin (2,3,7,8-TCDD) by O3 and NO3, were investigated employing quantum chemical calculations. For involved reactions, the microcosmic reaction processes were analyzed and depicted in detail based on geometry optimizations made by the B3LYP/6-31G(d) method. At the same time, the reaction activation energies were also calculated at the MP2/6- 311G(d,p)//B3LYP/6-31G(d) level. Configuration analysis indicated that 2,3,7,8-TCDD could be destroyed by 03 and NO3 in two different ways. The destruction of 2,3,7,8-TCDD by 03 proceeded via the addition of 03 and the cleavage of C=C while the destruction of 2,3,7,8-TCDD by NO3 proceeded via the substitution of chlorine by NO3. Calculated results show that, the activation energy of the destruction reaction of 2,3,7,8-TCDD by NO3 (267.48 kJ/mol) is much larger than that of the destruction reaction of 2,3,7,8-TCDD by O3 (51.20 kJ/mol). This indicated that the destruction of 2,3,7,8-TCDD by 03 is much more efficient than that of 2,3,7,8-TCDD by NO3. The reason why the activation energy for the destruction reaction of 2,3,7,8-TCDD by NO3 is so large, is also discussed. 展开更多
关键词 OZONE DIOXIN 2 3 7 8-tetrachlorodihenzo-p-dioxin Quantum chemistry destruction mechanism
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Determination of Optimum Conditions for Cell-wall Destruction of Auricularia auricula Mycelia under the Synergistic Effect of Ultrasonic Waves and Repeated Freeze-thaw Cycles 被引量:1
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作者 黄贤刚 鲁曾 胡晓文 《Agricultural Science & Technology》 CAS 2014年第8期1258-1261,共4页
We aimed to investigate the synergistic effects of ultrasonic waves and repeated freeze-thaw cycles on cel-wal destruction of Auricularia auric-ula mycelia, and determine the best combination of conditions for cel-wal... We aimed to investigate the synergistic effects of ultrasonic waves and repeated freeze-thaw cycles on cel-wal destruction of Auricularia auric-ula mycelia, and determine the best combination of conditions for cel-wal destruc-tion of Auricularia auricula mycelia. [Method] The effects of destruction time, added water, destruction times, freeze time and number of freeze-thaw cycles during ultra-sonic treatment on polysaccharide yield were investigated by single-factor test in our research. The optimum conditions for cel-wal destruction of Auricularia auricula mycelia by the synergistic effect of ultrasonic waves and repeated freeze-thaw cycles were ascertained by orthogonal test. [Result] The results of single test indicated the best combination of conditions was as fol ows: freeze time, 30 min; destruction time, 20 min; added water, 15 times; destruction times, 2 times; number of freeze-thaw cycles, 3 cycles. The results of orthogonal test indicated the influencing factors ranked as destruction time 〉 destruction times 〉 freeze time. The best combination of conditions was as fol ows: freeze time, 30 min; destruction time, 25 min; destruc-tion times, 2 times. Under above conditions, the polysaccharide yield reached 57.76 mg/g. [Conclusion] This research would provide a basis and reference for practical production. 展开更多
关键词 Ultrasonic waves-repeated freeze-thaw cycles Auricularia auricula mycelia Cel-wal destruction
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Destruction and Survival ——An Analysis of the Different Destinies of Pecola and Claudia in the Bluest Eye 被引量:1
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作者 肖志宏 《边疆经济与文化》 2009年第9期66-68,共3页
对比《最蓝的眼睛》中两个同为黑人社区贫穷家庭中的小女孩佩科拉与克劳迪亚截然不同的命运,从个人、家庭、社会三个角度分析造成两人完全不同命运的主要原因,可以看出莫里森的写作目的在于,向在文化冲突下的心灵扭曲的黑人群体指明... 对比《最蓝的眼睛》中两个同为黑人社区贫穷家庭中的小女孩佩科拉与克劳迪亚截然不同的命运,从个人、家庭、社会三个角度分析造成两人完全不同命运的主要原因,可以看出莫里森的写作目的在于,向在文化冲突下的心灵扭曲的黑人群体指明找回自我的方向:正视黑人自己的文化与身份,重构完整的自我才是生存的必由之路。 展开更多
关键词 毁灭 迷失 抗争 生存
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Amplitude.preserving plane-wave prestack time migration for AVO analysis 被引量:1
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作者 王棣 程玖兵 +2 位作者 郑晓东 王华忠 马在田 《Applied Geophysics》 SCIE CSCD 2008年第3期212-218,共7页
To support amplitude variation with offset (AVO) analysis in complex structure areas, we introduce an amplitude-preserving plane-wave prestack time migration approach based on the double-square-root wave equation in... To support amplitude variation with offset (AVO) analysis in complex structure areas, we introduce an amplitude-preserving plane-wave prestack time migration approach based on the double-square-root wave equation in media with little lateral velocity variation. In its implementation, a data mapping algorithm is used to obtain offset-plane-wave data sets from the common-midpoint gathers followed by a non-recursive phase-shift solution with amplitude correction to generate common-image gathers in offset-ray-parameter domain and a structural image. Theoretical model tests and a real data example show that our prestack time migration approach is helpful for AVO analysis in complex geological environments. 展开更多
关键词 plane-wave prestack time migration amplitude-preserving common-image gather
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基于Creative Destruction和模仿的增长模型
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作者 甄新 夏鹏涛 《湖北汽车工业学院学报》 2001年第2期48-51,71,共5页
本文对 Aghio和 Howitt基于 Schumpeterian Creative Destruction理论的增长模型进行改进 ,研究在企业间相互信息封锁的产品市场竞争的现实下 ,同一行业中的企业采用革新或模仿的单一策略来实现行业内的竞争时 ,对经济增长率产生的影响。
关键词 Creativedestruction 竞争 模仿 经济增长率 增长模型
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Self-Construction and Self-Destruction of Man:Reading The Lord of the Rings
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作者 曹长波 《海外英语》 2012年第12X期194-195,201,共3页
This essay is going to read the different kinds of beings in The Lord of the Rings as different stages of man,and to analyze how they construct or destruct their selves respectively over power.The Lord of the Rings is... This essay is going to read the different kinds of beings in The Lord of the Rings as different stages of man,and to analyze how they construct or destruct their selves respectively over power.The Lord of the Rings is read as a story about the self-construction and self-destruction of man,who begins to construct the sense of self from a very early stage in life,and becomes who he is in the continuous process of trying to identify himself with the image that keeps changing,of the frequently alternative construction and destruction of his self,and of intersubjectivity,the interrelation with other subjects. 展开更多
关键词 POWER SELF-CONSTRUCTION SELF-destruction
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Destruction of PCDD/Fs by gliding arc discharges 被引量:9
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作者 YAN Jian-hua PENG Zheng +5 位作者 LU Sheng-yong DU Chang-ming LI Xiao-dong CHEN Tong NI Ming-jiang CEN Ke-fa 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2007年第11期1404-1408,共5页
PCDD/Fs have been become a serious issue because of their toxicological effects and associated adverse health implications. In this study, the gliding arc plasma was tested for treatment of polychlorinated dibenzo-p-d... PCDD/Fs have been become a serious issue because of their toxicological effects and associated adverse health implications. In this study, the gliding arc plasma was tested for treatment of polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs), which was synthesized from pentachlorophenol in atmospheric condition at 350℃ with or without the catalysis of CuCl2. From the experiment, we found that the destruction efficiency of PCDD/F homologues after gliding was discharge ranged from 25% to 79%. This result demonstrates that gliding arc plasma is an effective technology to decompose PCDDs/Fs in flue gas. A plausible degradation mechanism for PCDD/Fs by gliding arc was discussed. Finally, a multistage reactor structure of gliding arc was proposed to upgrade removal efficiency for PCDD/Fs. 展开更多
关键词 PCDD/FS destruction gliding arc discharges multistage reactor
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Modeling of organic pollutant destruction in a stirred tank reactor by ozonation 被引量:2
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作者 CHENG Jiang YANG Zhuo-ru +2 位作者 CHEN Huan-qin KUO C.H. ZAPPI E.M. 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2001年第4期449-452,共4页
Destruction of organic contaminants in water by ozonation is a gas-liquid process which involves ozone mass transfer and fast irreversible chemical reactions. Ozonation reactor design and process optimizing require th... Destruction of organic contaminants in water by ozonation is a gas-liquid process which involves ozone mass transfer and fast irreversible chemical reactions. Ozonation reactor design and process optimizing require the modeling of the gas-liquid interactions within the reactor. In this paper a theoretical model combining the fluid dynamic and reaction kinetic parameters is proposed for predicting the destruction rates of organic pollutants in a semi-batch stirred-tank reactor by ozonation. A simple expression for the enhancement factor as our previous work has been applied to evaluate the chemical mass transfer coefficient in ozone absorption. 2,4-dichlorophenol (2,4-DCP) and 2,6-DCP or their mixture are chosen as the model compounds for simulating, and the predicted DCP concentrations are compared with some measured data. 展开更多
关键词 dichlorophenol destruction OZONATION stirred-tank reactor enhancement factor
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Overexpression of the neuroglobin gene delivered by ultrasound-targeted microbubble destruction protects SH-SY5Y cells against cobalt chloride induced hypoxia 被引量:3
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作者 Qian Yang Dianwen Gao +4 位作者 Qingzhu Nie Zhengang Cai Jian Du Lujuan Shan Yuejian Liu 《Neural Regeneration Research》 SCIE CAS CSCD 2011年第25期1947-1953,共7页
In this study, we examined the effects of neuroglobin gene (Ngb) transfection into SH-SY5Y cells, using ultrasound-targeted microbubble destruction (UTMD), on cobalt chloride-induced hypoxia. With an ultrasound in... In this study, we examined the effects of neuroglobin gene (Ngb) transfection into SH-SY5Y cells, using ultrasound-targeted microbubble destruction (UTMD), on cobalt chloride-induced hypoxia. With an ultrasound intensity of 0.8 W/cm2, a 60-second exposure duration, 50% duty cycle, and 20% microbubble concentration, pAcGFP1-C1-Ngb-transfected cells exhibited the highest cell viability and transfection efficiency. The efficiency of plasmid delivery was significantly higher with UTMD than transfection with plasmid alone, transfection with plasmid using microbubbles, or transfection of plasmid by ultrasound. In addition, during cobalt chloride-induced hypoxia, caspase-3 activity in pAcGFP1-C1-Ngb-transfected cells was significantly lower than in untransfected cells. Ngb protein and mRNA expression were significantly higher in cells transfected by UTMD than in cells transfected with the other methods. These results demonstrate that UTMD can very efficiently mediate exogenous gene delivery, and that Ngb overexpression protects cells against cobalt chloride-induced hypoxia. 展开更多
关键词 ultrasound-targeted microbubble destruction NEUROGLOBIN gene therapy recombinant plasmid SH-SY5Y cells neural regeneration
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Ultrasonic interventional analgesia in pancreatic carcinoma with chemical destruction of celiac ganglion 被引量:7
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作者 Tao Wang Fu-Zhou Tian Zhong-Hong Cai Xu Li Tao Cheng Li Shi Qi Cheng 《World Journal of Gastroenterology》 SCIE CAS CSCD 2006年第20期3288-3291,共4页
AIM: To detect the therapeutic effects of chemical destruction of celiac ganglion in patients with pancreatic carcinoma with intractable pain. METHODS: Ninety-seven cases with advanced pancreatic carcinoma received ... AIM: To detect the therapeutic effects of chemical destruction of celiac ganglion in patients with pancreatic carcinoma with intractable pain. METHODS: Ninety-seven cases with advanced pancreatic carcinoma received chemical destruction of celiac ganglion-5 mL pure alcohol injection around celiac artery under ultrasonic guidance. The changes of visual analogue scale (VAS), serum substance P (Sub P), β-endopeptide (β-EP) and T-lymphocyte subtypes level were compared between pre- and post-therapy. RESULTS: Successful rate of puncture was 98.7%, with one failure. No serious complications such as traumatic pancreatitis, pancreatic fistula, abdominal cavity hemorrhage or peritoneal infection occurred. VAS, serum Sub P and β-EP level significantly changed after treatment (8.0 ± 2.3 vs 4.6 ± 2.1, 254.1 ± 96.7 vs 182.4 ± 77.6, 3.2 ± 0.8 vs 8.8 ± 2.1, P 〈 0.01, P 〈 0.05, P 〈 0.01) with complete relief rate 54.2%, partial relief rate 21.9%, ineffective rate 12.5% and recurrent rate 10.7%. The T-lymphocyte subtypes level remarkably increased when compared with that of pre-therapy (46.7 ± 3.7 vs 62.5 ± 5.5, P 〈 0.01). CONCLUSION: Our study suggests that chemical destruction of celiac ganglion under ultrasonic guidance is highly safe, and can evidently relieve cancer pain and improve the cellular immunity in patients with advanced pancreatic carcinoma. 展开更多
关键词 Pancreatic carcinoma ANALGESIA Chemical destruction Ultrasonic intervention Celiac ganglion
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Coordination and evolution mechanism of fractal crack network in mining rock mass destruction 被引量:1
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作者 YU Guang-ming~1, ZHANG Chun-hui~2 (1. Qingdao Institute of Architecture and Engineering, Qingdao 266033, China 2. Liaoning Technical University, Fuxin 123000, China) 《中国有色金属学会会刊:英文版》 CSCD 2005年第S1期105-107,共3页
Based on the natural characters of stratum, complicated geological mining conditions and the essence of mining rock mass destruction, the complexity of rock mass destruction caused by miningw as analyzed. The inner li... Based on the natural characters of stratum, complicated geological mining conditions and the essence of mining rock mass destruction, the complexity of rock mass destruction caused by miningw as analyzed. The inner link between rock mass destruction phenomena caused by mining and nonlinear science was revealed. There are numerous cracks in natural rock mass. The cracks’ distribution is irregular and is of statistical fractal structure. Self-organizational nonlinear evolution of the inner structure flaws leads to the rock mass destruction with external force. The evolution includes single fault’s fractal development, formation and evolution of fractal crack network and coordination of fractal crack network, etc. The law of fractal crack network’s evolution was introduced, at the same time, the coordination of fractal crack network was analyzed. Finally, based on coordination the principal equation of mining-caused subsidence of structural rock mass was established and its steady-state solution and unsteady-state solution were found. 展开更多
关键词 the complexity of rock mass destruction FRACTAL CRACK NETWORK COORDINATION
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Kinetics study and analysis of zeolite Y destruction 被引量:5
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作者 杜晓辉 李雪礼 +1 位作者 张海涛 高雄厚 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2016年第2期316-323,共8页
A series of zeolites,including USY zeolites without sodium,Na-USY at different Na contents,La-USY with different rare earth(RE) contents and La-Na-USY with RE and Na were prepared by an ion exchange method.They were... A series of zeolites,including USY zeolites without sodium,Na-USY at different Na contents,La-USY with different rare earth(RE) contents and La-Na-USY with RE and Na were prepared by an ion exchange method.They were investigated to understand the activation barriers for the destruction of Y zeolite structure under hydrothermal treatment and the effect of V using the solid-state kinetic model.The results showed that the pathways for Y zeolite destruction were dealumination,desiliconization and the disappearance of La-O bonds.Zeolites were destroyed by steam through acid hydrolysis,which was accelerated by V.In addition,Na and V exerted a synergistic effect on the framework destruction,and the formation of NaOH was the rate-determining step.The presence of RE elements decreased hydrolysis and stabilized the structure of the zeolites.The interaction between V and RE destroyed zeolite structure by eliminating the stabilizing La-O[RE-OH-RE]^(5+)bridges in the sodalite cages. 展开更多
关键词 Y zeolite VANADIUM SODIUM Rare earth Hydrothermal stability destruction Apparent activation energy
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Efficient destruction of sodium cyanide by thermal decomposition with addition of ferric oxide 被引量:4
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作者 Kai-wei DONG Feng XIE +3 位作者 Wei WANG Yong-feng CHANG Chun-lin CHEN Xiao-wei GU 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2021年第4期1113-1126,共14页
Efficient destruction of cyanide by thermal decomposition with ferric oxide addition was proposed. The mechanism of destruction of sodium cyanide with or without ferric oxide addition under various conditions was exam... Efficient destruction of cyanide by thermal decomposition with ferric oxide addition was proposed. The mechanism of destruction of sodium cyanide with or without ferric oxide addition under various conditions was examined by XRD, DSC-TG, and chemical analysis technologies. In the absence of ferric oxide, sodium cyanide decomposes at 587.4 ℃ in air and 879.2 ℃ in argon atmosphere. In the presence of ferric oxide, about 60% of sodium cyanide decomposes at 350 ℃ for 30 min in argon, while almost all sodium cyanide decomposes within 30 min in air or O2 with mass ratio of ferric oxide to sodium cyanide of 1:1. The increase of ferric oxide addition, temperature, and heating time facilitates the destruction of sodium cyanide. It is believed that with ferric oxide addition, NaCN reacts with Fe2O3 to form Na4Fe(CN)6, Na2CO3, NaNO2 and Fe3O4 in argon. NaCN decomposes into NaCNO, Na4Fe(CN)6, minor NaNO2, and the formed NaCNO and Na4Fe(CN)6 further decompose into Na2CO3, CO2, N2, FeOx, and minor NOx in air or O2. 展开更多
关键词 cyanide destruction thermal decomposition ferric oxide catalytic oxidation sodium cyanide
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Ultrasound-triggered Microbubble Destruction in Combination with Cationic Lipid Microbubbles Enhances Gene Delivery 被引量:1
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作者 张丽 刘莹莹 +7 位作者 项光亚 吕清 黄桂 杨亚莉 张艳容 宋越 周欢 谢明星 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2011年第1期39-45,共7页
This study aimed to examine the preparation of cationic lipid microbubble(CLM),and evaluate its physical and chemical properties and toxicity,measure the gene transfection efficiency by ultrasound triggered microbob... This study aimed to examine the preparation of cationic lipid microbubble(CLM),and evaluate its physical and chemical properties and toxicity,measure the gene transfection efficiency by ultrasound triggered microbobble destruction(UTMD) in combination with CLM.The CLM was prepared by the method of the thin film hydration,and its morphology was observed under the electron microscopy at 1st,3rd,7th,10th,and 14th day after preparation,respectively.The size,Zeta potential and stability of CLM were tested.The acute toxicity of CLM was assessed.The green fluorescent protein gene(EGFP) transfection efficiency was evaluated.The experiment grouping was as follows:naked plasmid group(P group),ultrasonic irradiation plus naked plasmid group(P-US group),naked plasmid plus CLM group(P-CLM group),naked plasmid plus ultrasound and CLM group(UTMD group).The expression of EGFP was detected by fluorescent microscopy and flow cytometry.The results showed that CLMs were spherical in shape,with the similar size and good distribution degree under the light and electron microscopies.The size of CLMs was varied from 250.4±88.3 to 399.0±99.8 nm and the Zeta potential of CLMs from 18.80±4.97 to 20.1±3.1 mV.The EGFP expression was the strongest in the UTMD group,followed by the P-CLM group,P-US group and P group.Flow cytometry results were consistent with those of fluorescent microscopy.The transfection efficiency was substantially increased in the P-US group,P-CLM group and UTMD group as compared with that in the P group,almost 7 times,10 times and 30 times higher than that in the P group respectively.It is suggested that CLMs prepared by the method of thin film hydration are uniform in diameter,and proved non-toxic.UTMD combined with CLM can significantly increase the transfection efficiency of EGFP to targeted cells. 展开更多
关键词 ultrasound triggered microbubble destruction RNA interference gene
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Destruction of the Northern Margin of the North China Craton in Mid-Late Triassic: Evidence from Asthenosphere-derived Mafic Enclaves in the Jiefangyingzi Granitic Pluton from the Chifeng Area, Southern Inner Mongolia 被引量:3
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作者 LIU Jianfeng LI Jinyi +3 位作者 CHI Xiaoguo ZHENG Peixi HU Zhaochu ZHANG Xiaowei 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2020年第4期1071-1092,共22页
The petrology, geochronology and geochemistry of the mafic enclaves in the Mid-Late Triassic Jiefangyingzi pluton from Chifeng area, southern Inner Mongolia, in China are studied to reveal their petrogenetic relations... The petrology, geochronology and geochemistry of the mafic enclaves in the Mid-Late Triassic Jiefangyingzi pluton from Chifeng area, southern Inner Mongolia, in China are studied to reveal their petrogenetic relationship with the host pluton. Furthermore, the coeval magmatic assemblage and its petrogenesis on the northern margin of the North China craton(NCC) are studied synthetically to elucidate their tectonic setting and the implications for the destruction of the NCC. Zircon U-Pb dating reveals that the mafic enclaves formed at 230.4 ± 2.2 Ma, which is similar to the age of the host pluton. The most basic mafic enclaves belong to weak alkaline rocks, and they display rare earth element(REE) and trace element normalized patterns and trace element compositions similar to those of ocean island basalt(OIB). In addition, they have positive εNd(t) values(+3.84 to +4.94) similar to those of the Cenozoic basalts on the northern margin of the NCC. All of these geochemical characteristics suggest that the basic mafic rocks originated from the asthenosphere. Petrological and geochemical studies suggest that the Jiefangyingzi pluton and the intermediate mafic enclaves were formed by the mixing of the asthenosphere-derived and crust-derived magmas in different degrees. The Mid-Late Triassic magmatic rocks on the northern margin of the NCC could be classified into three assemblages according to their geochemical compositions: alkaline series, weak alkaline–sub-alkaline series and sub-alkaline series rocks. Petrogenetic analyses suggest that the upwelling of the asthenosphere played an important role in the formation of these Mid-Late Triassic magmatic rocks. Basing on an analysis of regional geological data, we suggest that the northern margin of the NCC underwent destruction due to the upwelling of the asthenosphere during the Mid-Late Triassic, which was induced by the delamination of the root of the collisional orogeny between Sino-Korean and Siberian paleoplates in Late Permian. 展开更多
关键词 mafic enclave craton destruction ASTHENOSPHERE Mid-Late Triassic North China craton
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