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A new method for quantitative evaluation of shale laminae using electrical image logging
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作者 Zhou Feng Hongliang Wu +4 位作者 Weilin Yan Han Tian Jiandong Zheng Chaoliu Li Kewen Wang 《Energy Geoscience》 EI 2024年第3期93-102,共10页
Shale oil reservoirs are generally characterized by complex mineral compositions, rapid lithofacies changes, and thin laminae. Explorations have confirmed that the type and density of shale laminae significantly influ... Shale oil reservoirs are generally characterized by complex mineral compositions, rapid lithofacies changes, and thin laminae. Explorations have confirmed that the type and density of shale laminae significantly influence reservoir quality, highlighting the importance of accurately identifying these laminae through well logging for effective shale reservoir evaluation. Presently, relevant technologies primarily focus on the qualitative identification of shale laminae using vertical slab images from image logs. However, influenced by the complex borehole conditions and image logging quality, this approach is less effective in identifying millimeter-scale laminae. This study proposes a new method for achieving high-resolution slab images and quantitatively evaluating the laminae using electrical image logs. The new method effectively improves the processing accuracy of slab images by delicately flattening and aligning the button electrode curves derived from electrical image logs point by point. Meanwhile, it allows for the accurate quantitative evaluation of the lamina number through precise identification of peaks and troughs in microelectrode curves. As demonstrated by the applications in shale oil reservoirs in the Gulong area in Daqing and the Ganchagou area in Qinghai, the proposed method can significantly improve accuracy compared to traditional slab images. Furthermore, the lamination index calculated using this method is highly consistent with the lamina number observed in cores. This study provides a new technical method for the quantitative lamina evaluation and rock structure analysis of shale reservoirs. 展开更多
关键词 Shale oil Slab image Lamina evaluation Lamination index
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Prediction of multiscale laminae structure and reservoir quality in fine-grained sedimentary rocks:The Permian Lucaogou Formation in Jimusar Sag,Junggar Basin 被引量:4
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作者 Xiao-Jiao Pang Gui-Wen Wang +8 位作者 Li-Chun Kuang Jin Lai Yang Gao Yi-Di Zhao Hong-Bin Li Song Wang Meng Bao Shi-Chen Liu Bing-Chang Liu 《Petroleum Science》 SCIE CAS CSCD 2022年第6期2549-2571,共23页
Fine-grained sedimentary rocks have become a research focus as important reservoirs and source rocks for tight and shale oil and gas.Laminae development determines the accumulation and production of tight and shale oi... Fine-grained sedimentary rocks have become a research focus as important reservoirs and source rocks for tight and shale oil and gas.Laminae development determines the accumulation and production of tight and shale oil and gas in fine-grained rocks.However,due to the resolution limit of conventional logs,it is challenging to recognize the features of centimeter-scale laminae.To close this gap,complementary studies,including core observation,thin section,X-ray diffraction(XRD),conventional log analysis,and slabs of image logs,were conducted to unravel the centimeter-scale laminae.The laminae recognition models were built using well logs.The fine-grained rocks can be divided into laminated rocks(lamina thickness of<0.01 m),layered rocks(0.01-0.1 m),and massive rocks(no layer or layer spacing of>0.1 m)according to the laminae scale from core observations.According to the mineral superposition assemblages from thin-section observations,the laminated rocks can be further divided into binary,ternary,and multiple structures.The typical mineral components,slabs,and T2spectrum distributions of various lamina types are unraveled.The core can identify the centimeter-millimeter-scale laminae,and the thin section can identify the millimeter-micrometer-scale laminae.Furthermore,they can detect mineral types and their superposition sequence.Conventional logs can identify the meter-scale layers,whereas image logs and related slabs can identify the laminae variations at millimeter-centimeter scales.Therefore,the slab of image logs combined with thin sections can identify laminae assemblage characteristics,including the thickness and vertical assemblage.The identification and classification of lamina structure of various scales on a single well can be predicted using conventional logs,image logs,and slabs combined with thin sections.The layered rocks have better reservoir quality and oil-bearing potential than the massive and laminated rocks.The laminated rocks’binary lamina is better than the ternary and multiple layers due to the high content of felsic minerals.The abovementioned results build the prediction model for multiscale laminae structure using well logs,helping sweet spots prediction in the Permian Lucaogou Formation in the Jimusar Sag and fine-grained sedimentary rocks worldwide. 展开更多
关键词 Fine-grained sedimentary rocks Mineral composition Multiscale laminae structure Reservoir quality Image logs Lucaogou formation
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Laminae combination and shale oil enrichment patterns of Chang 73 sub-member organic-rich shales in the Triassic Yanchang Formation, Ordos Basin, NW China 被引量:5
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作者 XI Kelai LI Ke +7 位作者 CAO Yingchang LIN Miruo NIU Xiaobing ZHU Rukai WEI Xinzhuo YOU Yuan LIANG Xiaowei FENG Shengbin 《Petroleum Exploration and Development》 2020年第6期1342-1353,共12页
The Chang 73 sub-member of Triassic Yanchang Formation in the Ordos Basin was taken as an example and the lamina types and combinations,reservoir space features and shale oil enrichment patterns in organic-rich shale ... The Chang 73 sub-member of Triassic Yanchang Formation in the Ordos Basin was taken as an example and the lamina types and combinations,reservoir space features and shale oil enrichment patterns in organic-rich shale strata were investigated using core observation,thin section analysis,XRF element measurement,XRD analysis,SEM,high solution laser Raman spectroscopy analysis,and micro-FTIR spectroscopy analysis,etc.According to the mineral composition and thickness of the laminae,the Chang 73 organic-rich shales have four major types of laminae,tuff-rich lamina,organic-rich lamina,silt-grade feldspar-quartz lamina and clay lamina.They have two kinds of shale oil-bearing layers,"organic-rich lamina+silt-grade feldspar-quartz lamina"and"organic-rich lamina+tuff-rich lamina"layers.In the"organic-rich+silt-grade feldspar-quartz"laminae combination shale strata,oil was characterized by relative high maturation,and always filled in K-feldspar dissolution pores in the silt-grade feldspar-quartz laminae,forming oil generation,migration and accumulation process between laminae inside the organic shales.In the"organic-rich+tuff-rich lamina"binary laminae combination shale strata,however,the reservoir properties were poor in organic-rich shales,the oil maturation was relatively lower,and mainly accumulated in the intergranular pores of interbedded thin-layered sandstones.The oil generation,migration and accumulation mainly occurred between organic-rich shales and interbedded thin-layered sandstones. 展开更多
关键词 organic-rich shale laminae combination oil enrichment patterns shale oil Triassic Yanchang Formation Ordos Basin
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Ultrathin Wood Laminae–Thermoplastic Starch Biodegradable Composites 被引量:1
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作者 Andrea Dorigato Martino Negri Alessandro Pegoretti 《Journal of Renewable Materials》 SCIE 2018年第5期493-503,共11页
Novel fully biodegradable thermoplastic composite laminates reinforced with ultrathin wood laminae were prepared through a hot-pressing process by using two different thermoplastic starch(TPS)matrices.The microstructu... Novel fully biodegradable thermoplastic composite laminates reinforced with ultrathin wood laminae were prepared through a hot-pressing process by using two different thermoplastic starch(TPS)matrices.The microstructure and physical properties of the resulting unidirectional and bidirectional laminates were studied.The investigated materials presented a complex microstructure,in which the porosity of the wood laminae was almost entirely occluded by the polymer matrix.The mechanical behavior of the laminates was strongly affected by the obtained microstructure,and matrix penetration in wood pores led to biodegradable composites with elastic modulus and tensile strength higher than those of their constituents.Finally,thermal welding and thermoformability tests proved how these materials possess features typical of thermoplastic materials. 展开更多
关键词 STARCH ultrathin wood laminae COMPOSITES mechanical properties
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Reservoir characteristics and genetic mechanisms of gas-bearing shales with different laminae and laminae combinations: A case study of Member 1 of the Lower Silurian Longmaxi shale in Sichuan Basin, SW China 被引量:2
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作者 SHI Zhensheng DONG Dazhong +2 位作者 WANG Hongyan SUN Shasha WU Jin 《Petroleum Exploration and Development》 2020年第4期888-900,共13页
Based on thin-section,argon-ion polished large-area imaging and nano-CT scanning data,the reservoir characteristics and genetic mechanisms of the Lower Silurian Longmaxi shale layers with different laminae and laminae... Based on thin-section,argon-ion polished large-area imaging and nano-CT scanning data,the reservoir characteristics and genetic mechanisms of the Lower Silurian Longmaxi shale layers with different laminae and laminae combinations in the Sichuan Basin were examined.It is found that the shale has two kinds of laminae,clayey lamina and silty lamina,which are different in single lamina thickness,composition,pore type and structure,plane porosity and pore size distribution.The clayey laminae are about 100μm thick each,over 15%in organic matter content,over 70%in quartz content,and higher in organic pore ratio and plane porosity.They have abundant bedding fractures and organic matter and organic pores connecting with each other to form a network.In contrast,the silty laminae are about 50μm thick each,5%to 15%in organic matter content,over 50%in carbonate content,higher in inorganic pore ratio,undeveloped in bedding fracture,and have organic matter and organic pores disconnected from each other.The formation of mud lamina and silt lamina may be related to the flourish of silicon-rich organisms.The mud lamina is formed during the intermittent period,and silt lamina is formed during the bloom period of silicon-rich organisms.The mud laminae and silt laminae can combine into three types of assemblages:strip-shaped silt,gradating sand-mud and sand-mud thin interlayers.The strip-shaped silt assemblage has the highest porosity and horizontal/vertical permeability ratio,followed by the gradating sand-mud assemblage and sand-mud thin interlayer assemblage.The difference in the content ratio of the mud laminae to silt laminae results in the difference in the horizontal/vertical permeability ratio. 展开更多
关键词 gas-bearing shale lamina reservoir characteristics genetic mechanism Lower Silurian Longmaxi Formation Sichuan Basin
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Laminae characteristics of gas-bearing shale fine-grained sediment of the Silurian Longmaxi Formation of Well Wuxi 2 in Sichuan Basin,SW China 被引量:1
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作者 SHI Zhensheng QIU Zhen +3 位作者 DONG Dazhong LU Bin LIANG Pingping ZHANG Mengqi 《Petroleum Exploration and Development》 2018年第2期358-368,共11页
Based on various test data, the composition, texture, structure and lamina types of gas-bearing shale were determined based on Well Wuxi 2 of the Silurian Longmaxi Formation in the Sichuan Basin. Four types of lamina,... Based on various test data, the composition, texture, structure and lamina types of gas-bearing shale were determined based on Well Wuxi 2 of the Silurian Longmaxi Formation in the Sichuan Basin. Four types of lamina, namely organic-rich lamina, organic-bearing lamina, clay lamina and silty lamina, are developed in the Longmaxi Formation of Well Wuxi 2, and they form 2 kinds of lamina set and 5 kinds of beds. Because of increasing supply of terrigenous clasts and enhancing hydrodynamics and associated oxygen levels, the contents of TOC and brittle mineral reduce and content of clay mineral increases gradually as the depth becomes shallow. Organic-rich lamina, organic-rich + organic-bearing lamina set and organic-rich bed dominate the small layers 1-3 of Member 1 of the Longmaxi Formation, suggesting anoxic and weak hydraulic depositional setting. Organic-rich lamina, along with organic-bearing lamina and silty lamina, appear in small layer 4, suggesting increased oxygenated and hydraulic level. Small layers 1-3 are the best interval and drilling target of shale gas exploration and development. 展开更多
关键词 Sichuan Basin Longmaxi Formation FINE-GRAINED SEDIMENT SHALE GAS lamina WELL WUXI 2
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Effect of forced lamina flow on microsegregation simulated by phase field method quantitatively 被引量:4
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作者 王军伟 王智平 +3 位作者 路阳 朱昌盛 冯力 肖荣振 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2012年第2期391-397,共7页
The influence of supercooled melt forced lamina flow on microsegregation was investigated. The concentration distribution at solid-liquid boundary of binary alloy Ni-Cu was simulated using phase field model coupled wi... The influence of supercooled melt forced lamina flow on microsegregation was investigated. The concentration distribution at solid-liquid boundary of binary alloy Ni-Cu was simulated using phase field model coupled with flow field. The microsegregation, concentration maximum value, boundary thickness of concentration near upstream dendrite and normal to flow dendrite, and downstream dendrite were studied quantitatively in the case of forced lamia flow. The simulation results show that solute field and flow field interact complexly. Compared with melt without flow, in front of upstream dendrite tip, the concentration boundary thickness is the lowest and the concentration maximum value is the smallest for melt with flow. However, in front of downstream dendrite tip, the results are just the opposite. The zone of poor Cu in upstream dendrite where is the most severely microsegregation and shrinkage cavity is wider and the concentration is lower for melt with flow than that without flow. 展开更多
关键词 computer simulation phase field method solidification forced lamina flow MICROSEGREGATION solute redistribution shrinkage cavity
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左西孟旦对扩张型心肌病的作用及机制 被引量:10
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作者 袁文金 李文峰 +4 位作者 罗刚 张丹丹 王诚高 刘罗英 罗骏 《中国老年学杂志》 CAS 北大核心 2019年第1期175-177,共3页
目的研究左西孟旦如何通过调控LMNA致病基因作用于扩张型心肌病的机制。方法通过培养HCM细胞,借助转染反义干扰LMNA(si-LMNA)基因和反义干扰核糖核酸(siRNA ctrl)基因分别作为si-LMNA组、siRNA ctrl组、si-LMNA+左西孟旦组,应用无血清... 目的研究左西孟旦如何通过调控LMNA致病基因作用于扩张型心肌病的机制。方法通过培养HCM细胞,借助转染反义干扰LMNA(si-LMNA)基因和反义干扰核糖核酸(siRNA ctrl)基因分别作为si-LMNA组、siRNA ctrl组、si-LMNA+左西孟旦组,应用无血清培养基、正常血清培养基〔10%胎牛血清(FBS)培养基〕及左西孟坦处理液培养转染后的细胞,通过MTT比色法检测细胞存活率,定量多聚酶链反应(qPCR)、Western印迹法分析心脏钠通道蛋白(SCN) 5A蛋白的变化。结果 si-LMNA降低LMNA蛋白的表达,沉默的LMNA基因抑制人心肌细胞HCM的存活率;加入左西孟旦可逆转上述趋势。左西孟旦可逆转LMNA基因沉默引起的SCN5A蛋白的降低。结论左西孟旦作用于LMNA基因上调SCN5A基因的表达,这可能是其治疗扩张型心肌病的机制之一。 展开更多
关键词 左西孟旦 扩张型心肌病 LaminA/C核纤层蛋白(LMNA) 心脏钠通道蛋白(SCN)5A
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核基质蛋白LaminA/C在正常乳腺和乳腺癌组织中的差异表达 被引量:2
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作者 何谦 张淑群 +2 位作者 赵丽华 王香玲 楚雍烈 《中国肿瘤临床》 CAS CSCD 北大核心 2010年第9期495-498,共4页
目的:采用比较蛋白质组学方法研究正常乳腺和乳腺癌组织中的差异表达核基质蛋白(nuclear matrix protein,NMP),并在蛋白质水平对差异蛋白LaminA/C进一步地确证。方法:分别提取4例正常乳腺和乳腺癌组织的核基质蛋白,进行双向凝胶电泳。... 目的:采用比较蛋白质组学方法研究正常乳腺和乳腺癌组织中的差异表达核基质蛋白(nuclear matrix protein,NMP),并在蛋白质水平对差异蛋白LaminA/C进一步地确证。方法:分别提取4例正常乳腺和乳腺癌组织的核基质蛋白,进行双向凝胶电泳。分离出的差异表达蛋白质点进行基质辅助激光解吸电离飞行时间质谱(MALDI-TOF-MS)分析,获得肽质量指纹图谱(Peptide Mass Fingerprinting,PMF),应用Mascot搜索引擎在NCBInr数据库中进行检索鉴定。最后用免疫组化和Western blotting方法验证差异蛋白LaminA/C在正常乳腺和乳腺癌组织的相对表达量。结果:经双向凝胶电泳和质谱鉴定,正常乳腺组含有(904±58)个蛋白质点,乳腺癌组检测出含有(944±70)个蛋白质点,共发现27个差异表达蛋白,成功鉴定出12种蛋白,其中包括LaminA/C。用免疫组化方法分析LaminA/C在正常乳腺和乳腺癌组织各20例中的表达,结果显示LaminA/C在正常乳腺和乳腺癌组织中的阳性率分别为15%(3/20)和40%(8/20),P<0.05。用Western blot方法观察LaminA/C在正常乳腺和乳腺癌组织各10例中的表达,结果显示乳腺癌组中LaminA/C/β-actin灰度值比值为0.40±0.13,是正常乳腺组LaminA/C/β-actin灰度值比值(0.21±0.13)的1.91倍(P<0.05)。结论:LaminA/C在乳腺癌组织中表达明显增高,LaminA/C蛋白在乳腺癌的发生和发展中可能起一定的作用。 展开更多
关键词 蛋白质组学 LaminA/C 乳腺癌
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核纤层蛋白Lamin A的结构及功能和代谢特征 被引量:1
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作者 马延超 许寿生 +1 位作者 周越 王瑞元 《中国组织工程研究与临床康复》 CAS CSCD 北大核心 2009年第46期9167-9170,共4页
Lamin A是细胞核内重要的骨架蛋白,对维持细胞的形态结构具有重要作用。文章综述了LMN A基因在染色体的位置lamin A蛋白质的形态、结构;LMN A基因不同位点的突变和缺失时机体产生的不同疾病;核纤层蛋白lamin A参与成肌细胞的分化作用功... Lamin A是细胞核内重要的骨架蛋白,对维持细胞的形态结构具有重要作用。文章综述了LMN A基因在染色体的位置lamin A蛋白质的形态、结构;LMN A基因不同位点的突变和缺失时机体产生的不同疾病;核纤层蛋白lamin A参与成肌细胞的分化作用功能;Caspase-6可促进核纤层蛋白lamin A的裂解以及NFAT5可能促进lamin A的表达等调节作用。 展开更多
关键词 LAMINA 功能 代谢
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核纤层蛋白LaminA/C负性调控ASCs增殖促进应力诱导脂肪再生的实验研究
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作者 任婧 万玲玲 +1 位作者 鲁峰 陈曦航 《中国临床解剖学杂志》 CSCD 北大核心 2021年第4期420-425,共6页
目的探索核纤层蛋白LaminA/C对脂肪来源间充质干细胞(Adipose-derived stromal cells,ASCs)机械敏感性的调控作用,及其在应力诱导脂肪再生中的作用机制。方法构建大鼠预扩张脂肪瓣(Expanded Prefabricated Adipose Tissue,EPAT)负压吸... 目的探索核纤层蛋白LaminA/C对脂肪来源间充质干细胞(Adipose-derived stromal cells,ASCs)机械敏感性的调控作用,及其在应力诱导脂肪再生中的作用机制。方法构建大鼠预扩张脂肪瓣(Expanded Prefabricated Adipose Tissue,EPAT)负压吸引模型,于术后1、4、8周取材制备标本,行组织免疫印迹及免疫化学检测核纤层蛋白(Lamins)表达量变化,用以分析核纤层蛋白表达与应力诱导脂肪再生的相关性;构建体外LaminA/C过表达慢病毒载体并转染ASCs,行体外静态拉伸ASCs处理并采用细胞免疫印迹及免疫荧光检测ASCs增殖程度,用以明确LaminA/C对ASCs增殖的调控作用。结果体内实验发现,负压作用早期,大鼠EPAT内ASCs增殖增多,与此同时,脂肪瓣内LaminA/C表达量明显下降,LaminB1、LaminB2的表达则无明显差异;体外实验发现,过表达LaminA/C可显著抑制体外静态机械应力对ASCs增殖的促进作用。结论新型力学感受器核纤层蛋白通过负性调ASCs增殖参与应力诱导脂肪组织再生过程。 展开更多
关键词 核纤层蛋白(LaminA/C) 脂肪来源间充质干细胞 机械应力 大鼠预扩张脂肪瓣(EPAT)
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Clostridium butyricum alleviates intestinal low-grade inflammation in TNBS-induced irritable bowel syndrome in mice by regulating functional status of lamina propria dendritic cells 被引量:22
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作者 Qin Zhao Wen-Rong Yang +5 位作者 Xiao-Hong Wang Gai-Qin Li Lei-Qi Xu Xiao Cui Yang Liu Xiu-Li Zuo 《World Journal of Gastroenterology》 SCIE CAS 2019年第36期5469-5482,共14页
BACKGROUND Irritable bowel syndrome (IBS) is one of the most common functional gastroenterological diseases characterized by abnormal visceral sensitivity and lowgrade inflammation. The role of Clostridium butyricum (... BACKGROUND Irritable bowel syndrome (IBS) is one of the most common functional gastroenterological diseases characterized by abnormal visceral sensitivity and lowgrade inflammation. The role of Clostridium butyricum (C. butyricum) in reducing intestinal low-grade inflammation via immune pathways has been well defined. However, the detailed mechanisms of the effects of C. butyricum on intestinal mucosal immunity, especially on immune cells of the lamina propria, remain unclear. Dendritic cells (DCs), which are important immune cells, secrete proinflammatory cytokines (IL-1β, IL-6, and others) and express T cell immunoglobulin and mucin domain-3 (TIM3), promoting proliferation and activation of DCs, and mediating Th1 and Th17 inflammatory responses. AIM To investigate the role of DCs in the development of IBS in a rat model and to understand the regulation of DCs after C. butyricum intervention. METHODS An IBS animal model was established using C57BL/6 mice, and C. butyricum was continuously administered via the intragastric route to simulate different intestinal immune states. Intestinal visceral hypersensitivity and histopathology were assessed using the abdominal withdrawal reflex (AWR) test and hematoxylin & eosin (H&E) staining, respectively. The expression of proinflammatory cytokines (IL-1β and IL-6) and TIM3 was analyzed by Western blot analysis and real-time PCR. Flow cytometry was applied to analyze the quantity, function, and membrane molecule TIM3 of the lamina propria dendritic cells (LPDCs). The regulatory effect of C. butyricum was verified in bone marrowderived dendritic cells by in vitro experiments. RESULTS The secretion of proinflammatory cytokines (IL-1β and IL-6) in mice with IBS was significantly increased compared with that of the control group, which suggested that the intestinal mucosa in mice with IBS was in a low-grade inflammatory state. The expression of CD11C+CD80+ and CD11c+TIM3+ in intestinal LPDCs in mice with IBS increased significantly. Meanwhile, the cytokines (IL-1β and IL-6) were significantly reduced after the intervention with probiotic C. butyricum. The amount and function of LPDCs and the TIM3 on the surface of the LPDCs were decreased with the alleviation of the intestinal inflammatory response. CONCLUSION The results suggest that C. butyricum regulates the amount and functional status of LPDCs in the intestinal mucosa of mice with IBS, and therefore modulates the local immune response in the intestine. 展开更多
关键词 CLOSTRIDIUM butyricum IRRITABLE bowel syndrome LAMINA propria dendritic cells T cell immunoglobulin and MUCIN domain-3 PROINFLAMMATORY cytokines
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Molecular mechanism of action of anti-tumor necrosis factor antibodies in inflammatory bowel diseases 被引量:20
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作者 Ulrike Billmeier Walburga Dieterich +1 位作者 Markus F Neurath Raja Atreya 《World Journal of Gastroenterology》 SCIE CAS 2016年第42期9300-9313,共14页
Anti-tumor necrosis factor(TNF) antibodies are successfully used in the therapy of inflammatory bowel diseases(IBD). However, the molecular mechanism of action of these agents is still a matter of debate. Apart from n... Anti-tumor necrosis factor(TNF) antibodies are successfully used in the therapy of inflammatory bowel diseases(IBD). However, the molecular mechanism of action of these agents is still a matter of debate. Apart from neutralization of TNF, influence on the intestinal barrier function, induction of apoptosis in mucosal immune cells, formation of regulatory macrophages as well as other immune modulating properties have been discussed as central features. Nevertheless, clinically effective anti-TNF antibodies were shown to differ in their mode-of-action in vivo and in vitro. Furthermore, the anti-TNF agent etanercept is effective in the treatment of rheumatoid arthritis but failed to induce clinical response in Crohn's disease patients, suggesting different contributions of TNF in the pathogenesis of these inflammatory diseases. In the following, we will review different aspects regarding the mechanism of action of anti-TNF agents in general and analyze comparatively different effects of each antiTNF agent such as TNF neutralization, modulation of the immune system, reverse signaling and induction of apoptosis. We discuss the relevance of the membranebound form of TNF compared to the soluble form for the immunopathogenesis of IBD. Furthermore, we review reports that could lead to personalized medicine approaches regarding treatment with antiTNF antibodies in chronic intestinal inflammation, by predicting response to therapy. 展开更多
关键词 Mucosal immunology Lamina propria mononuclear cells Crohn’s disease Ulcerative colitis Transmembrane tumor necrosis factor APOPTOSIS
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Determination of Fullerenes (C60/C70) from the Permian-Triassic Boundary in the Meishan Section of South China 被引量:10
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作者 LIYanfang LIANGHandong +4 位作者 YINHongfu SUNJing CAIHou'an RAOZhu RANFanlin 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2005年第1期11-15,共5页
Fullerenes (C 60 /C 70 ), clays and rocks near the Permian-Triassic (P/T) boundary in the Meishan section of South China are explored by means of comprehensive analytical techniques, including ultrasonic extraction wi... Fullerenes (C 60 /C 70 ), clays and rocks near the Permian-Triassic (P/T) boundary in the Meishan section of South China are explored by means of comprehensive analytical techniques, including ultrasonic extraction with column purification, high-performance liquid chromatography (HPLC) and matrix assisted laser desorption/ionization time-of- flight mass spectrometry (MALDI TOF MS). The study confirms the existence of fullerenes toward the P/T event boundary and their absence in clays and limestones beyond the boundary. In particular, the white clay, known as the event boundary, contains fullerenes of 0.33 ppb, while the red material, as the first lamina fill of goethite and gypsum on the base of the white clay, contains fullerenes of 1.23 ppb, and the last lamina of 2.50 ppb. Significantly, distinct enrichment of fullerenes is coincident with the disappearance of fossil records of marine species (94%) just at the base of the white clay, implying that geological fullerenes would be one of temporal remnants led by the P/T catastrophic event. This work strongly supports that fullerenes would be one of significant records of the P/T catastrophic event but their origin remains to be studied further. 展开更多
关键词 FULLERENES mass extinction PERMIAN-TRIASSIC laminas Meishan section China
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Intestinal barrier: A gentlemen's agreement between microbiota and immunity 被引量:11
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作者 Andrea Moro Caricilli Angela Castoldi Niels Olsen Saraiva Cmara 《World Journal of Gastrointestinal Pathophysiology》 CAS 2014年第1期18-32,共15页
Our body is colonized by more than a hundred trillion commensals, represented by viruses, bacteria and fungi. This complex interaction has shown that the microbiome system contributes to the host's adaptation to i... Our body is colonized by more than a hundred trillion commensals, represented by viruses, bacteria and fungi. This complex interaction has shown that the microbiome system contributes to the host's adaptation to its environment, providing genes and functionality that give flexibility of diet and modulate the immune system in order not to reject these symbionts. In the intestine,specifically, the microbiota helps developing organ structures, participates of the metabolism of nutrients and induces immunity. Certain components of the microbiota have been shown to trigger inflammatory responses, whereas others, anti-inflammatory responses.The diversity and the composition of the microbiota,thus, play a key role in the maintenance of intestinal homeostasis and explain partially the link between intestinal microbiota changes and gut-related disorders in humans. Tight junction proteins are key molecules for determination of the paracellular permeability. In the context of intestinal inflammatory diseases, the intestinal barrier is compromised, and decreased expression and differential distribution of tight junction proteins is observed. It is still unclear what is the nature of the luminal or mucosal factors that affect the tight junctionproteins function, but the modulation of the immune cells found in the intestinal lamina propria is hypothesized as having a role in this modulation. In this review,we provide an overview of the current understanding of the interaction of the gut microbiota with the immune system in the development and maintenance of the intestinal barrier. 展开更多
关键词 MICROBIOTA IMMUNE system LAMINA propria INTESTINAL barrier
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Gingival-derived mesenchymal stem cells:An endless resource for regenerative dentistry 被引量:6
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作者 Mohammed E Grawish 《World Journal of Stem Cells》 SCIE CAS 2018年第9期116-118,共3页
The gingiva, the masticatory portion of the oral mucosa, is excised and discarded frequently during routine dental treatments and following tooth extraction, dental crown lengthening, gingivectomy and periodontal surg... The gingiva, the masticatory portion of the oral mucosa, is excised and discarded frequently during routine dental treatments and following tooth extraction, dental crown lengthening, gingivectomy and periodontal surgeries. Subsequent to excision, healing eventually happens in a short time period after gingival surgery. Clinically, the gingival tissue can be collected very easily and, in the laboratory, it is also very easy to isolate gingival-derived mesenchymal stem cells (GMSCs) from this discarded gingival tissue. GMSCs, a stem cell population within the lamina propria of the gingival tissue, can be isolated from attached and free gingiva, inflamed gingival tissu-es, and from hyperplastic gingiva. Comparatively, they constitute more attractive alternatives to other dental-derived mesenchymal stem cells due to the availability and accessibility of gingival tissues. They have unique immunomodulatory functions and well-documented self-renewal and multipotent differentiation properties. They display positive signals for Stro-1, Oct-4 and SSEA-4 pluripotency-associated markers, with some co-expre-ssing Oct4/Stro-1 or Oct-4/SSEA-4. They should be considered as the best stem cell source for cell-based therapies and regenerative dentistry. The clinical use of GMSCs for regenerative dentistry represents an attrac-tive therapeutic modality. However, numerous biological and technical challenges need to be addressed prior to considering transplantation approaches of GMSCs as clinically realistic therapies for humans. 展开更多
关键词 Gingival-derived mesenchymal STEM cells REGENERATIVE DENTISTRY Lamina propria of the GINGIVA GINGIVA STEM cell therapy
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Eosinophils in the gastrointestinal tract and their role in the pathogenesis of major colorectal disorders 被引量:8
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作者 Alexandre Loktionov 《World Journal of Gastroenterology》 SCIE CAS 2019年第27期3503-3526,共24页
Eosinophils are currently regarded as versatile mobile cells controlling and regulating multiple biological pathways and responses in health and disease.These cells store in their specific granules numerous biological... Eosinophils are currently regarded as versatile mobile cells controlling and regulating multiple biological pathways and responses in health and disease.These cells store in their specific granules numerous biologically active substances(cytotoxic cationic proteins, cytokines, growth factors, chemokines,enzymes) ready for rapid release. The human gut is the main destination of eosinophils that are produced and matured in the bone marrow and then transferred to target tissues through the circulation. In health the most important functions of gut-residing eosinophils comprise their participation in the maintenance of the protective mucosal barrier and interactions with other immune cells in providing immunity to microbiota of the gut lumen. Eosinophils are closely involved in the development of inflammatory bowel disease(IBD),when their cytotoxic granule proteins cause damage to host tissues. However,their roles in Crohn’s disease and ulcerative colitis appear to follow different immune response patterns. Eosinophils in IBD are especially important in altering the structure and protective functions of the mucosal barrier and modulating massive neutrophil influx to the lamina propria followed by transepithelial migration to colorectal mucus. IBD-associated inflammatory process involving eosinophils then appears to expand to the mucus overlaying the internal gut surface. The author hypothesises that immune responses within colorectal mucus as well as ETosis exerted by both neutrophils and eosinophils on the both sides of the colonic epithelial barrier act as additional pathogenetic factors in IBD. Literature analysis also shows an association between elevated eosinophil levels and better colorectal cancer(CRC) prognosis, but mechanisms behind this effect remain to be elucidated. In conclusion, the author emphasises the importance of investigating colorectal mucus in IBD and CRC patients as a previously unexplored milieu of disease-related inflammatory responses. 展开更多
关键词 EOSINOPHILS Eosinophilopoiesis Gut lamina propria COLORECTAL MUCUS NORMAL HUMAN small intestine NORMAL HUMAN colon Inflammatory bowel DISEASE Crohn’s DISEASE Ulcerative colitis COLORECTAL cancer
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The application of machine learning under supervision in identification of shale lamina combination types——A case study of Chang 7_(3)sub-member organic-rich shales in the Triassic Yanchang Formation,Ordos Basin,NW China 被引量:3
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作者 Yuan-Yuan Zhang Ke-Lai Xi +5 位作者 Ying-Chang Cao Bao-Hai Yu Hao Wang Mi-Ruo Lin Ke Li Yang-Yang Zhang 《Petroleum Science》 SCIE CAS CSCD 2021年第6期1619-1629,共11页
Organic rich laminated shale is one type of favorable reservoirs for exploration and development of continental shale oil in China.However,with limited geological data,it is difficult to predict the spatial distributi... Organic rich laminated shale is one type of favorable reservoirs for exploration and development of continental shale oil in China.However,with limited geological data,it is difficult to predict the spatial distribution of laminated shale with great vertical heterogeneity.To solve this problem,taking Chang 73 sub-member in Yanchang Formation of Ordos Basin as an example,an idea of predicting lamina combinations by combining'conventional log data-mineral composition prediction-lamina combination type identification'has been worked out based on machine learning under supervision on the premise of adequate knowledge of characteristics of lamina mineral components.First,the main mineral components of the work area were figured out by analyzing core data,and the log data sensitive to changes of the mineral components was extracted;then machine learning was used to construct the mapping relationship between the two;based on the variations in mineral composition,the lamina combination types in typical wells of the research area were identified to verify the method.The results show the approach of'conventional log data-mineral composition prediction-lamina combination type identification'works well in identifying the types of shale lamina combinations.The approach was applied to Chang 73 sub-member in Yanchang Formation of Ordos Basin to find out planar distribution characteristics of the laminae. 展开更多
关键词 Organic-rich shale laminae combination Conventional logs Machine learning Ordos Basin
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Erdheim chester-A rare disease with unique endoscopic features 被引量:3
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作者 Gil Ben-yaakov Daniela Munteanu +2 位作者 Ignacio Sztarkier Alexer Fich Doron Schwartz 《World Journal of Gastroenterology》 SCIE CAS 2014年第25期8309-8311,共3页
Erdheim-Chester disease(ECD) is a rare inflammatory syndrome in which systemic infiltration of non-Langerhans cell histiocytes occurs in different sites. Both the etiology and pathophysiology of ECD are unknown, but C... Erdheim-Chester disease(ECD) is a rare inflammatory syndrome in which systemic infiltration of non-Langerhans cell histiocytes occurs in different sites. Both the etiology and pathophysiology of ECD are unknown, but CD68 positive CD 1a/S100 negative cells are characteristic. The presentation of ECD differs according to the involved organs. This case report describes a patient with ECD and the gastrointestinal manifestations and unique endoscopic appearance as seen in gastroscopy and colonoscopy with histological proof of histiocyte infiltration of the lamina propria. The clinical and endoscopic findings of this unique case, to our knowledge, were never described before, so were the features of the gastrointestinal involvement in this disease. 展开更多
关键词 Erdheim chester HISTIOCYTES Lamina propria COLON STOMACH
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Symmetric Equations for Evaluating Maximum Torsion Stress of Rectangular Beams in Compliant Mechanisms 被引量:3
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作者 Gui-Min Chen Larry L.Howell 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2018年第1期34-40,共7页
There are several design equations available for calculating the torsional compliance and the maximum torsion stress of a rectangular cross-section beam, but most depend on the relative magnitude of the two dimensions... There are several design equations available for calculating the torsional compliance and the maximum torsion stress of a rectangular cross-section beam, but most depend on the relative magnitude of the two dimensions of the crosssection(i.e., the thickness and the width). After reviewing the available equations, two thickness-to-width ratio Independent equations that are symmetric with respect to the two dimensions are obtained for evaluating the maximum torsion stress of rectangular cross-section beams. Based on the resulting equations, outside lamina emergent torsional joints are analyzed and some useful design Insights are obtained. These equations, together with the previous work on symmetric equations for calculating torsional compliance, provide a convenient and effective way for designing and optimizing torsional beams in compliant mechanisms. 展开更多
关键词 Compliant mechanism Maximum torsion stress Rectangular beam Lamina emergent joint
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