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Development of 0.5-V Josephson junction array devices for quantum voltage standards
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作者 王兰若 李劲劲 +2 位作者 曹文会 钟源 张钟华 《中国物理B:英文版》 SCIE EI CAS CSCD 2019年第6期453-457,共5页
The design, fabrication, and the characterization of a 0.5-V Josephson junction array device are presented for the quantum voltage standards in the National Institute of Metrology(NIM) of China. The device consists of... The design, fabrication, and the characterization of a 0.5-V Josephson junction array device are presented for the quantum voltage standards in the National Institute of Metrology(NIM) of China. The device consists of four junction arrays, each of which has 1200 3-stacked Nb/NbxSi1-x/Nb junctions and an on-chip superconducting microwave circuit which is mainly a power divider enabling each Josephson array being loaded with an equal amount of microwave power. A direct current(dc) quantum voltage of about 0.5 V with a ~1-mA current margin of the 1 st quantum voltage step is obtained.To further prove the quality of NIM device, a comparison between the NIM device with the National Institute of Standards and Technology(NIST) programmable Josephson voltage standard(PJVS) system device is conducted. The difference of the reproduced 0.5-V quantum voltage between the two devices is about 0.55 nV, which indicates good agreement between the two devices. With the homemade device, we have realized a precise and applicable 0.5-V applicable-level quantum voltage. 展开更多
关键词 JOSEPHSON VOLTAGE standards JOSEPHSON JUNCTION superconducting-normal metal–superconducting(SNS) JUNCTION QUANTUM device
Beneficial effects of nutritional supplements on intestinal epithelial barrier functions in experimental colitis models in vivo 预览
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作者 Hilda Vargas-Robles Karla Fabiola Castro-Ochoa +1 位作者 AlíFrancisco Citalán-Madrid Michael Schnoor 《世界胃肠病学杂志:英文版》 SCIE CAS 2019年第30期4181-4198,共18页
Acute and chronic colitis affect a huge proportion of the population world-wide.The etiology of colitis cases can be manifold,and diet can significantly affect onset and outcome of colitis.While many forms of acute co... Acute and chronic colitis affect a huge proportion of the population world-wide.The etiology of colitis cases can be manifold,and diet can significantly affect onset and outcome of colitis.While many forms of acute colitis are easily treatable,chronic forms of colitis such as ulcerative colitis and Crohn’s disease(summarized as inflammatory bowel diseases)are multifactorial with poorly understood pathogenesis.Inflammatory bowel diseases are characterized by exacerbated immune responses causing epithelial dysfunction and bacterial translocation.There is no cure and therapies aim at reducing inflammation and restoring intestinal barrier function.Unfortunately,most drugs can have severe side effects.Changes in diet and inclusion of nutritional supplements have been extensively studied in cell culture and animal models,and some supplements have shown promising results in clinical studies.Most of these nutritional supplements including vitamins,fatty acids and phytochemicals reduce oxidative stress and inflammation and have shown beneficial effects during experimental colitis in rodents induced by dextran sulphate sodium or 2,4,6-trinitrobenzene sulfonic acid,which remain the gold standard in pre-clinical colitis research.Here,we summarize the mechanisms through which such nutritional supplements contribute to epithelial barrier stabilization. 展开更多
关键词 Colitis DEXTRAN sulphate sodium 2 4 6-trinitrobenzene sulfonic acid Tight JUNCTION Adherens JUNCTION PHYTOCHEMICALS BUTYRATE VITAMINS Short chain fatty acids MICRONUTRIENTS
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句子逻辑语义交际功能的双重性
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作者 张家骅 《语言学研究》 2019年第1期73-84,共12页
句子和名词短语一样,也具有概念和指物的双重性。命题为逻辑语义交际结构述位的句子表达广义指物意义;真值模态为逻辑语义交际结构述位的句子表达广义概念意义;情景命题和真值模态共同为逻辑语义交际结构述位的叙述话语句是不可切分句,... 句子和名词短语一样,也具有概念和指物的双重性。命题为逻辑语义交际结构述位的句子表达广义指物意义;真值模态为逻辑语义交际结构述位的句子表达广义概念意义;情景命题和真值模态共同为逻辑语义交际结构述位的叙述话语句是不可切分句,表达广义指物意义。从属小句和从属名词化述谓短语、紧缩修饰短语是句子的二级述谓单位,它们不直接参与句子逻辑语义交际结构切分,但常常是惯常意义实际切分的直接成分。二级述谓单位自身逻辑语义功能性质,主要取决于语法主导词的语法、语义和语用类型。 展开更多
关键词 指物意义 概念意义 逻辑语义交际结构切分 名词化述谓短语 修饰短语
The role of connexin43 in neuropathic pain induced by spinal cord injury
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作者 Anhui Wang Changshui Xu 《生物化学与生物物理学报:英文版》 SCIE CAS CSCD 2019年第6期555-561,共7页
Neuropathic pain is caused by the damage or dysfunction of the nervous system. In many neuropathic pain models, there is an increase in the number of gap junction (GJ) channels, especially the upregulation of the expr... Neuropathic pain is caused by the damage or dysfunction of the nervous system. In many neuropathic pain models, there is an increase in the number of gap junction (GJ) channels, especially the upregulation of the expression of connexin43 (Cx43), leading to the secretion of various types of cytokines and involvement in the formation of neuropathic pain. GJs are widely distributed in mammalian organs and tissues, and Cx43 is the most abundant connexin (Cx) in mammals. Astrocytes are the most abundant glial cell type in the central nervous system (CNS),which mainly express Cx43. More importantly, GJs play an important role in regulating cell metabolism, signaling, and function. Many existing literatures showed that Cx43 plays an important role in the nervous system, especially in the CNS under normal and pathological conditions. However, many internal mechanisms have not yet been thoroughly explored. In this review, we summarized the current understanding of the role and association of Cx and pannexin chan nets in neuropathic pain, especially after spinal cord injury, as well as some of our own in sights and thoughts which suggest that Cx43 may become an emerging therapeutic target for future neuropathic pain, bringing new hope to patients. 展开更多
关键词 connexin43 astrocytes gap junction NEUROPATHIC pain SPINAL CORD injury
Study on variation trend of repetitive nerve stimulation waveform in amyotrophic lateral sclerosis
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作者 Li-Lan Fu He-Xiang Yin +1 位作者 Ming-Sheng Liu Li-Ying Cui 《中华医学杂志:英文版》 SCIE CAS CSCD 2019年第5期542-550,共9页
Background: Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative disease involving both upper and lower neurons with no effective cure. Electrophysiological studies have found decremental responses d... Background: Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative disease involving both upper and lower neurons with no effective cure. Electrophysiological studies have found decremental responses during low-frequency repetitive nerve stimulation (RNS) except for diffused neurogenic activities. However, the difference between ALS and generalized myasthenia gravis (GMG) in terms of waveform features is unclear. In the current study, we explored the variation trend of the amplitudes curve between ALS and GMG with low-frequency, positive RNS, and the possible mechanism is discussed preliminarily. Methods: A total of 85 ALS patients and 41 GMG patients were recruited. All patients were from Peking Union Medical College Hospital (PUMCH) between July 1,2012 and February 28,2015. RNS study included ulnar nerve, accessory nerve and facial nerve at 3 Hz and 5 Hz stimulation. The percentage reduction in the amplitude of the fourth or fifth wave from the first wave was calculated and compared with the normal values of our hospital. A 15% decrease in amplitude is defined as a decrease in amplitude. Results: The decremental response at low-frequency RNS showed the abnormal rate of RNS decline was 54.1%(46/85) in the ALS group, and the results of different nerves were 54.1 %(46/85) of the accessory nerve, 8.2%(7/85) of the ulnar nerve and 0%(0/85) of the facial nerve stimulation, respectively. In the GMG group, the abnormal rate of RNS decline was 100%(41/41) at low-frequency RNS of accessory nerves. However, there was a significant difference between the 2 groups in the amplitude after the sixth wave. Conclusions: Both groups of patients are able to show a decreasing amplitude of low-frequency stimulation RNS, but the recovery trend after the sixth wave has significant variation. It implies the different pathogenesis of NMJ dysfunction of these 2 diseases. 展开更多
关键词 Amyotrophic lateral SCLEROSIS Generalized MYASTHENIA GRAVIS NEUROMUSCULAR junction REPETITIVE nerve stimulation
The impact of GJA3 SNPs on susceptibility to age-related cataract
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作者 Xia-Jing Tang Xing-Chao Shentu +2 位作者 Ye-Lei Tang Xi-Yuan Ping Xiao-Ning Yu 《国际眼科杂志:英文版》 SCIE CAS 2019年第6期1008-1011,共4页
AIM: To determine the association of gap junction protein alpha 3(GJA3) gene tag single-nucleotide polymorphisms(SNPs) with susceptibility to age-related cataract(ARC).METHODS: In total, 486 ARC patients were matched ... AIM: To determine the association of gap junction protein alpha 3(GJA3) gene tag single-nucleotide polymorphisms(SNPs) with susceptibility to age-related cataract(ARC).METHODS: In total, 486 ARC patients were matched with 500 healthy controls. All the participants underwent complete ophthalmic examinations. Haplotype-tagging SNPs of GJA3 gene were selected from the HapMap Beijing Han Chinese population. Genomic DNA was extracted from the peripheral blood leukocytes of all the subjects.Under three different genetic models: dominant, recessive,and additive, the association between SNPs and ARC was examined. After adjusting for age and sex, the genetic effects of the GJA3 SNPs were evaluated with logistic regression analysis.RESULTS: Four tag GJA3 SNPs(rs6490519, rs9506430,rs9509053, and rs9552089) were included in the present study. None of the SNPs showed a significant relationship with an altered risk of total ARC under the dominant,recessive, or additive models. In the subgroup analysis,rs9506430 had a significant effect on the formation of a posterior subcapsular cataract(P=0.002, OR: 0.227, 95%CI:0.088-0.590) under the recessive model.CONCLUSION: Our study indicates that GJA3 variants may influence the development of posterior subcapsular cataracts. Further studies need to be designed to confirm this possibility. 展开更多
关键词 gap JUNCTION protein alpha 3 single-nucleotide POLYMORPHISMS AGE-RELATED CATARACT
Seismic behavior of slab-structural wall junction of RC building 预览
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作者 Snehal Kaushik Kaustubh Dasgupta 《地震工程与工程振动:英文版》 SCIE EI CSCD 2019年第2期331-349,共19页
In high seismic zone regions, slender reinforced concrete structural walls are commonly used in high-rise buildings as a main lateral load resisting element. These walls are very effective in limiting the lateral drif... In high seismic zone regions, slender reinforced concrete structural walls are commonly used in high-rise buildings as a main lateral load resisting element. These walls are very effective in limiting the lateral drift of the building due to their large in-plane stiffness. However, the presence of floor slabs influences the behavior of the shear wall. Also, the current design requirements do not account for the presence of floor slabs. To understand the behavior of wall-slab junctions and address the shortcomings of the current design requirements, the influence of two parameters, namely(a) aspect ratio and(b) longitudinal reinforcement ratio on the behavior is studied numerically. It is observed that the presence of floor slabs at different levels tends to partition the wall into squat wall panels between two consecutive floors. The wall-slab junctions show large stress concentrations arising from the strut action in the squat panels. It is also observed that the floor slabs can get significantly damaged near the wall-slab junction for lower vertical reinforcement ratios in the wall. Thus, the current codeprescribed minimum reinforcement in shear walls is not sufficient and needs to be revisited at for improved performance. 展开更多
关键词 RC WALL building wall-slab JUNCTION SEISMIC damage nonlinear STATIC analysis
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Constraint-induced movement therapy enhances angiogenesis and neurogenesis after cerebral ischemia/reperfusion 预览
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作者 Zhi-Yong Zhai Juan Feng 《中国神经再生研究:英文版》 SCIE CAS CSCD 2019年第10期1743-1754,共12页
Constraint-induced movement therapy after cerebral ischemia stimulates axonal growth by decreasing expression levels of Nogo-A,RhoA,and Rho-associated kinase(ROCK)in the ischemic boundary zone.However,it remains uncle... Constraint-induced movement therapy after cerebral ischemia stimulates axonal growth by decreasing expression levels of Nogo-A,RhoA,and Rho-associated kinase(ROCK)in the ischemic boundary zone.However,it remains unclear if there are any associations between the Nogo-A/RhoA/ROCK pathway and angiogenesis in adult rat brains in pathological processes such as ischemic stroke.In addition,it has not yet been reported whether constraint-induced movement therapy can promote angiogenesis in stroke in adult rats by overcoming Nogo-A/RhoA/ROCK signaling.Here,a stroke model was established by middle cerebral artery occlusion and reperfusion.Seven days after stroke,the following treatments were initiated and continued for 3 weeks:forced limb use in constraint-induced movement therapy rats(constraint-induced movement therapy group),intraperitoneal infusion of fasudil(a ROCK inhibitor)in fasudil rats(fasudil group),or lateral ventricular injection of NEP1-40(a specific antagonist of the Nogo-66 receptor)in NEP1-40 rats(NEP1-40 group).Immunohistochemistry and western blot assay results showed that,at 2 weeks after middle cerebral artery occlusion,expression levels of RhoA and ROCK were lower in the ischemic boundary zone in rats treated with NEP1-40 compared with rats treated with ischemia/reperfusion or constraint-induced movement therapy alone.However,at 4 weeks after middle cerebral artery occlusion,expression levels of RhoA and ROCK in the ischemic boundary zone were markedly decreased in the NEP1-40 and constraint-induced movement therapy groups,but there was no difference between these two groups.Compared with the ischemia/reperfusion group,modified neurological severity scores and foot fault scores were lower and time taken to locate the platform was shorter in the constraint-induced movement therapy and fasudil groups at 4 weeks after middle cerebral artery occlusion,especially in the constraint-induced movement therapy group.Immunofluorescent staining demonstrated that fasudil promoted an immune response of nerve-regene 展开更多
关键词 nerve REGENERATION constraint-induced movement therapy ANGIOGENESIS ISCHEMIA/REPERFUSION subventricular zone Nogo-A FASUDIL NEUROVASCULAR unit tight junction protein vascular endothelial growth factor receptor 2 neural REGENERATION
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汉宜铁路变电所牵引回流不畅原因分析及对策研究 预览
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作者 于小四 徐学平 《电气化铁道》 2019年第3期30-34,共5页
针对汉宜铁路浩口变电所馈出供电臂内牵引回流不畅问题进行检测分析,确定了牵引回流不畅的供电臂及存在问题的设备,并制定了针对性整治措施,整治后达到预期效果,对含综合接地系统的直接供电方式牵引回流问题研究具有借鉴意义。
关键词 客运专线 牵引回流 综合地线 结合部
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Current surgical treatment of esophagogastric junction adenocarcinoma 预览
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作者 Shun Zhang Hajime Orita Tetsu Fukunaga 《世界胃肠肿瘤学杂志:英文版(电子版)》 CAS 2019年第8期567-578,共12页
The incidence of esophagogastric junction(EGJ)adenocarcinoma has shown an upward trend over the past several decades worldwide.In this article,we review previous studies and aimed to provide an update on the factors r... The incidence of esophagogastric junction(EGJ)adenocarcinoma has shown an upward trend over the past several decades worldwide.In this article,we review previous studies and aimed to provide an update on the factors related to the surgical treatment of EGJ adenocarcinoma.The Siewert classification has implications for lymph node spread and is the most commonly used classification.Different types of EGJ cancer have different incidences of mediastinal and abdominal lymph node metastases,and different surgical approaches have unique advantages and disadvantages.Minimally invasive surgeries have been increasingly applied in clinical practice and show comparable oncologic outcomes.Endoscopic resection may be a good therapy for early EGJ cancer.Additionally,there is still a great need for well-designed,large RCTs to forward our knowledge on the surgical treatment of EGJ cancer. 展开更多
关键词 Esophagogastric JUNCTION cancer SURGERY LYMPH NODES Siewert classification
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Electron-deficient core fused-ring based non-fullerene acceptor enables over 15%efficiency in single junction organic solar cells
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作者 Hongzheng Chen 《中国科学:化学英文版》 SCIE EI CAS CSCD 2019年第4期403-404,共2页
Organic solar cells(OSCs)are promising to access flexible,light weight and semi-transparent photovoltaic devices by low-cost solution fabrication.Recently,the fused-ring nonfullerene acceptors play an important role i... Organic solar cells(OSCs)are promising to access flexible,light weight and semi-transparent photovoltaic devices by low-cost solution fabrication.Recently,the fused-ring nonfullerene acceptors play an important role in promoting the research progress of the OSCs.The power conversion efficiencies(PCEs)have been rapidly boosted to over 14%in single junction OSCs with the development of new nonfullerene acceptors and the related devices[1-3].Although the PCEs of OSCs are still inferior to their inorganic counterparts,further improvement of the PCEs could be expected by the development of new photovoltaic materials. 展开更多
关键词 ELECTRON-DEFICIENT CORE SINGLE JUNCTION non-fullerene ACCEPTOR
Shuxuetong injection protects cerebral microvascular endothelial cells against oxygen-glucose deprivation reperfusion 预览
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作者 Zuo-Yan Sun Fu-Jiang Wang +6 位作者 Hong Guo Lu Chen Li-Juan Chai Rui-Lin Li Li-Min Hu Hong Wang Shao-Xia Wang 《中国神经再生研究:英文版》 SCIE CAS CSCD 2019年第5期783-793,共11页
Shuxuetong injection composed of leech(Hirudo nipponica Whitman)and earthworm(Pheretima aspergillum)has been used for the clinical treatment of acute stroke for many years in China.However,the precise neuroprotective ... Shuxuetong injection composed of leech(Hirudo nipponica Whitman)and earthworm(Pheretima aspergillum)has been used for the clinical treatment of acute stroke for many years in China.However,the precise neuroprotective mechanism of Shuxuetong injection remains poorly understood.Here,cerebral microvascular endothelial cells(bEnd.3)were incubated in glucose-free Dulbecco’s modified Eagle’s medium containing 95%N2/5%CO2 for 6 hours,followed by high-glucose medium containing 95%O2 and 5%CO2 for 18 hours to establish an oxygen-glucose deprivation/reperfusion model.This in vitro cell model was administered Shuxuetong injection at 1/32,1/64,and 1/128 concentrations(diluted 32-,64-,and 128-times).Cell Counting Kit-8 assay was used to evaluate cell viability.A fluorescence method was used to measure lactate dehydrogenase,and a fluorescence microplate reader used to detect intracellular reactive oxygen species.A fluorescent probe was also used to measure mitochondrial superoxide production.A cell resistance meter was used to measure transepithelial resistance and examine integrity of monolayer cells.The fluorescein isothiocyanate-dextran test was performed to examine blood-brain barrier permeability.Real-time reverse transcription polymerase chain reaction was performed to analyze mRNA expression levels of tumor necrosis factor alpha,interleukin-1β,interleukin-6,and inducible nitric oxide synthase.Western blot assay was performed to analyze expression of caspase-3,intercellular adhesion molecule 1,vascular cell adhesion molecule 1,occludin,vascular endothelial growth factor,cleaved caspase-3,B-cell lymphoma 2,phosphorylated extracellular signal-regulated protein kinase,extracellular signal-regulated protein kinase,nuclear factor-κB p65,I kappa B alpha,phosphorylated I kappa B alpha,I kappa B kinase,phosphorylated I kappa B kinase,claudin-5,and zonula occludens-1.Our results show that Shuxuetong injection increases bEnd.3 cell viability and B-cell lymphoma 2 expression,reduces cleaved caspase-3 expression,inhibits produ 展开更多
关键词 nerve REGENERATION SHUXUETONG injection brain MICROVASCULAR endothelial cells oxygen-glucose deprivation/reperfusion tight junction proteins mitochondrial function inflammatory factors blood-brain barrier neuroprotection neural REGENERATION
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Delta-doped quantum wire tunnel junction for highly concentrated solar cells
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作者 Ali Bahrami Mahyar Dehdast +1 位作者 Shahram Mohammadnejad Habib Badri Ghavifekr 《中国物理B:英文版》 SCIE EI CAS CSCD 2019年第4期275-279,共5页
We propose a novel structure for tunnel junction based on delta-doped AlGaAs/GaAs quantum wires. Higher spatial confinement of quantum wires alongside the increased effective doping concentration in the delta-doped re... We propose a novel structure for tunnel junction based on delta-doped AlGaAs/GaAs quantum wires. Higher spatial confinement of quantum wires alongside the increased effective doping concentration in the delta-doped regions extremely increase the peak tunneling current and enhance the performance of tunnel junction. The proposed structure can be used as tunnel junction in the multijunction solar cells under the highest possible thermodynamically limited solar concentration.The combination of the quantum wire with the delta-doped structure can be of benefit to the solar cells’ advantages including higher number of sub-bands and high degeneracy. Simulation results show a voltage drop of 40 mV due to the proposed tunnel junction used in a multijunction solar cell which presents an extremely low resistance to the achieved peak tunneling current. 展开更多
关键词 delta-doping quantum wire SOLAR cell TUNNEL JUNCTION
Thermoelec tricity in B80-based single-molecule junc ti ons: First-principles investigation
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作者 Ying-Xiang Zhen Ming Yang Rui-Ning Wang 《物理学前沿:英文版》 SCIE CSCD 2019年第2期83-88,共6页
Thermoelectricity is a therrnorelated property that is of great importance in single-molecule junctions. The electrical conductance (σ), electron-derived thermal conductance(kel) and Seebeck coefficient (S) of Bgo-ba... Thermoelectricity is a therrnorelated property that is of great importance in single-molecule junctions. The electrical conductance (σ), electron-derived thermal conductance(kel) and Seebeck coefficient (S) of Bgo-based single-molecule junctions are investigated by using density functional theory in combination with non-equilibrium Green's function. When the dist ance bet ween the left/right elec trodes is 11.4 A, the relationship between σ and kel obeys the Wiedemann-Franz law very well because of the strong hybridization between B80 molecular orbitals and the surface states of Au electrodes. Furthermore, the calculated Lorenz number is close to the famous value in metal or degenerate semiconductors. In addition, S is only —19.09 μV/K at 300 K, thus leading to the smaller electron's thermoelec trie figure of merit (ZeiT = S^2 σT / Kel). Interestingly, the st rain and chemical pot ential can modulate B80-based single-molecule junctions from n-type to p-type when the compressive strain reaches —0.6 A or the chemical potential shifts to —0.16 eV. This might be attributed that S reflects the asymmetry in the electrical conductance with respect to the chemical potential and is proportional to the slopes of the transmission spectrum. 展开更多
关键词 THERMOELECTRICITY SINGLE-MOLECULE JUNCTION NON-EQUILIBRIUM Green FUNCTION
T型三通管冷热流体掺混数值模拟 预览
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作者 邹智鑫 王合旭 +1 位作者 蒋彦龙 李泽伟 《计算机辅助工程》 2019年第1期46-52,共7页
针对T型三通管冷热流体掺混现象经常引发管道热疲劳甚至部件失效的问题,基于FLUENT混合雷诺平均N-S方程(Reynolds averaged N-S equations,RANS)和大涡模拟(large eddy simulation,LES)方法,对其管内冷热流体掺混问题进行仿真模拟。对... 针对T型三通管冷热流体掺混现象经常引发管道热疲劳甚至部件失效的问题,基于FLUENT混合雷诺平均N-S方程(Reynolds averaged N-S equations,RANS)和大涡模拟(large eddy simulation,LES)方法,对其管内冷热流体掺混问题进行仿真模拟。对划分的LES和RANS计算域分别采用壁面模拟LES(wall-modeledLES,WMLES)和k-ωSST模型进行计算,并将数值模拟结果与实验数据进行对比。分析功率谱密度(power spectral density,PSD),预测管内冷热流体掺混过程的热疲劳敏感位置,结果表明:数值模拟预测结果与实验数据吻合度较高,热疲劳敏感位置也与实际情况相符合。混合RANS-LES方法适用于T型三通管冷热流体掺混问题研究。 展开更多
关键词 T型三通管 冷热流体掺混 功率谱密度 热疲劳
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Activation of SIRT1 ameliorates LPS-induced lung injury in mice via decreasing endothelial tight junction permeability
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作者 Cui-ping Fu Sheng-yu Hao +6 位作者 Xiao-bo Xu Jian Zhou Zi-long Liu Huan Lu Li-min Wang Wei-zhong Jin Shan-qun Li 《中国药理学报:英文版》 SCIE CAS CSCD 2019年第5期630-641,共12页
The integrity of the endothelial barrier is a determinant of the prognosis of lipopolysaccharide (LPS)-induced acute lung injury (ALI). In this study, we investigated whether and how Sirtuin 1 (SIRT1) maintained the v... The integrity of the endothelial barrier is a determinant of the prognosis of lipopolysaccharide (LPS)-induced acute lung injury (ALI). In this study, we investigated whether and how Sirtuin 1 (SIRT1) maintained the vascular integrity during ALI. An experimental model of ALI was established in mice through intratracheal administration of LPS (10 mg/kg). LPS stimulation significantly increased the pulmonary permeability and decreased the expression of SIRT1 and tight junction proteins (TJs), including occludin, claudin-5, tight junction protein 1 and tight junction protein 2. Morphological studies showed that LPS induced obvious lung injury with inammatory cell infiltration in the interstitial and alveolar space, hemorrhage, edema, and the thickened alveolar wall compared to the control mice. Intratracheal administration of the selective SIRT1 activator SRT1720 (6.25 mg/kg) significantly attenuated LPS- induced lung injury, lung hyper-permeability and increased TJs expression, whereas intratracheal administration of the selective SIRT1 inhibitor EX527 (6.25 mg/kg) aggravated LPS-induced ALI. Similar protective effects of SIRT1 on pulmonary cellular permeability were observed in primary human pulmonary microvascular endothelial cells treated with LPS (2 mg/mL) in vitro. We further demonstrated that the RhoA/ROCK signaling pathway was activated in SIRT1 regulation of tight junction permeability. The RhoA/ROCK inhibitor Y-27632 (10 μM) increased the expression of TJs and reversed LPS- or EX527-induced hyper-permeability. In conclusion, SIRT1 ameliorates LPS-induced lung injury via decreasing endothelial tight junction permeability, possibly via RhoA/ ROCK signaling pathway. This finding may contribute to the development of new therapeutic approaches for lung injury. 展开更多
关键词 lung injury LPS SIRT1 protein RhoA/ROCK capillary ENDOTHELIAL PERMEABILITY tight junction proteins SRT1720 EX527 Y-27632 human pulmonary MICROVASCULAR ENDOTHELIAL cells
Presence of antibodies against low-density lipoprotein receptor-related protein 4 and impairment of neuromuscular junction in a Chinese cohort of amyotrophic lateral sclerosis
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作者 Lin Lei Xin-Ming Shen +8 位作者 Shu-Yan Wang Yan Lu Suo-Bin Wang Hai Chen Zheng Liu Ya-Sheng Ouyang Jian-Ying Duo Yu-Wei Da Zhi-Guo Chen 《中华医学杂志:英文版》 SCIE CAS CSCD 2019年第12期1487-1489,共3页
Amyotrophic lateral sclerosis (ALS) is a heterogeneous disorder characterized by a loss of upper and lower motor neurons with neither clear pathogenesis nor effective treatment. Thus, potential biomarkers are needed t... Amyotrophic lateral sclerosis (ALS) is a heterogeneous disorder characterized by a loss of upper and lower motor neurons with neither clear pathogenesis nor effective treatment. Thus, potential biomarkers are needed to classify the disease and find new drug targets. Previous studies have shown that auto-antibodies against the low-density lipoprotein receptor-related protein 4 (LRP4), called the anti-LRP4 antibodies, are found in ~23% patients of Greek and Italian ALS cohorts,[1] and in 10% of the American ALS population.[2] Anti-LRP4 antibodies were previously identified in myasthenia gravis (MG), the most common neuromuscular junction (NMJ) disorder, and were shown to cause NMJ abnormality in animal studies.[3] Here, we studied anti-LRP4 antibodies in Chinese patients and investigated the correlation between anti-LRP4 antibodies and abnormal neuromuscular transmission in ALS. 展开更多
关键词 ANTIBODIES AGAINST amyotrophic lateral SCLEROSIS NEUROMUSCULAR junction
Esophagogastric junction outflow obstruction successfully treated with laparoscopic Heller myotomy and Dor fundoplication:First case report in the literature 预览
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作者 Pedro F Pereira Andre RP Rosa +6 位作者 Leonardo A Mesquita Marcelle J Anzolch Rafael N Branchi Augusto L Giongo Francisco C Paixao Marcio F Chedid Cleber DP Kruel 《世界胃肠外科杂志:英文版(电子版)》 2019年第2期112-116,共5页
BACKGROUND Esophagogastric junction outflow obstruction(EGJOO)is a rare syndrome,characterized by an elevation of the integrated relaxation pressure of the lower esophageal sphincter,not accompanied by alterations in ... BACKGROUND Esophagogastric junction outflow obstruction(EGJOO)is a rare syndrome,characterized by an elevation of the integrated relaxation pressure of the lower esophageal sphincter,not accompanied by alterations in esophageal motility that may lead to the criteria for achalasia.We were unable to find any prior report of the combination of Heller myotomy with anterior partial fundoplication(Dor)as the treatment for EGJOO.We herein report a case of EGJOO treated with laparoscopic Heller myotomy combined with Dor fundoplication.CASE SUMMARY A 26-year-old man presented with a 3-year history of solid dysphagia and a 30-kg weight loss.He was treated with oral nifedipine,isosorbide,and omeprazole,without resolution of symptoms.An upper gastrointestinal series(barium swallow)revealed a“bird’s beak”sign.Esophagogastroduodenoscopy was positive for Los Angeles grade A peptic esophagitis.High-resolution esophageal manometry was compatible with EGJOO.Esophageal pH monitoring showed pathological acid reflux both in orthostatic and decubitus position.An 8-cm laparoscopic Heller myotomy combined with an anterior 220°Dor fundoplication was performed.Solid diet was introduced on postoperative day 2,and the patient was discharged home the same day.At 17-mo follow-up,he reported no symptoms.Barium swallow was compatible with complete radiologic resolution.Both esophageal manometry and upper endoscopy showed normal findings 9 mo after the operation.CONCLUSION Surgical treatment with Heller myotomy and Dor fundoplication is a potential treatment option for EGJOO refractory to medical treatment. 展开更多
关键词 Esophagogastric JUNCTION OUTFLOW OBSTRUCTION HELLER MYOTOMY Partial FUNDOPLICATION Dor FUNDOPLICATION Case report
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Surgical resection of gastric stump cancer following proximal gastrectomy for adenocarcinoma of the esophagogastric junction 预览
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作者 Fu-Hai Ma Li-Yan Xue +7 位作者 Ying-Tai Chen Wei-Kun Li Yang Li Wen-Zhe Kang Yi-Bin Xie Yu-Xin Zhong Quan Xu Yan-Tao Tian 《世界胃肠肿瘤学杂志:英文版(电子版)》 CAS 2019年第5期416-423,共8页
BACKGROUND Proximal gastrectomy (PG) is performed widely as a function-preserving operation for early gastric cancer located in the upper third of the stomach and is an important function-preserving approach for esoph... BACKGROUND Proximal gastrectomy (PG) is performed widely as a function-preserving operation for early gastric cancer located in the upper third of the stomach and is an important function-preserving approach for esophagogastric junction (EGJ) adenocarcinoma. The incidence of gastric stump cancer (GSC) after PG is increasing. However, little is known about the GSC following PG because very few studies have been conducted on the disease. AIM To clarify clinicopathologic features, perioperative complications, and long-term survival rates after the resection of GSC following PG. METHODS Data for patients with GSC following PG for adenocarcinoma of the EGJ diagnosed between January 1998 and December 2016 were retrospectively reviewed. Multivariate analysis was performed to identify factors associated with overall survival (OS). GSC was defined in accordance with the Japanese Gastric Cancer Association. RESULTS A total of 35 patients were identified. The median interval between the initial PG and resection of GSC was 4.9 (range 0.7-12) years. In 21 of the 35 patients, the tumor was located in a nonanastomotic site of the gastric stump. Total gastrectomy was performed in 27 patients;the other 8 underwent partial gastrectomy. Postoperative complications occurred in 6 patients (17.1%). The tumor stage according to the depth of tumor invasion was T1 in 6 patients, T2 in 3 patients, T3 in 9 patients, and T4 in 17 patients. Lymph node metastasis was observed in 18 patients. Calculated 1-, 3-, and 5-year OS rates were 86.5%, 62.3%, and 54.2%, respectively. Multivariate analysis showed advanced T stage to be associated with OS. CONCLUSION This study reveals the characteristics of GSC following PG for adenocarcinoma of the EGJ and suggests that a surgical approach can lead to a satisfactory outcome. 展开更多
关键词 GASTRIC stump cancer PROXIMAL GASTRECTOMY Esophagogastric JUNCTION DISTAL GASTRECTOMY
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Photo-controlled release of paclitaxel and model drugs from RNA pyramids
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作者 Congcong Xu Hui Li +4 位作者 Kaiming Zhang Daniel W.Binzel Hongran Yin Wah Chiu Peixuan Guo 《纳米研究:英文版》 SCIE EI CAS CSCD 2019年第1期41-48,共8页
Stimuli-resp on sive release of drugs from a nano carrier in spatial-,temporal-,and dosage-controlled fashi ons is of great interest in the pharmaceutical industry.Paclitaxel is one of the most effective and popular c... Stimuli-resp on sive release of drugs from a nano carrier in spatial-,temporal-,and dosage-controlled fashi ons is of great interest in the pharmaceutical industry.Paclitaxel is one of the most effective and popular chemotherapeutic drugs against a number of cancers such as metastatic or non metastatic breast can cer,non-small cell lung can cer,refractory ovaria n cancer,AIDS-related Kaposi's sarcoma,and head and neck can cers.Here,by taki ng the adva ntage of RNA nanotechno logy in biomedical and material scie nee,we developed a three-dime nsional pyramid-shaped RNA nanocage for a photocontrolled release of cargo,using paclitaxel as a model drug.The light-triggered release of paclitaxel or fluorophore Cy5 was achieved by incorporation of photocleavable spacers into the RNA nanoparticles.Upon irradiation with ultraviolet light,cargos were rapidly released(within 5 min).In vitro treatment of breast can cer cells with the RNA nano particles harbori ng photocleavable paclitaxel showed higher cytotoxicity as compared to RNA nanoparticles without the photocleavable spacer.The methodology provides proof of con cept for the applicati on of the light-triggered con trolled release of drugs from RNA nano cages. 展开更多
关键词 RNA NANOTECHNOLOGY controlled release PACLITAXEL DRUG delivery RNA nanoparticles Phi29 three-way JUNCTION
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