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| 1 | Ischemia/reperfusion injury and cardioprotective mechanisms:Role of mitochondria and reactive oxygen species显示文摘Reperfusion therapy must be applied as soon as possible to attenuate the ischemic insult of acute myocardial infarction(AMI).However reperfusion is responsible for additional myocardial damage,which likely involves opening of the mitochondrial permeability transition pore(mPTP).In reperfusion injury,mitochondrial damage is a determining factor in causing loss of cardiomyocyte function and viability.Major mechanisms of mitochondrial dysfunction include the long lasting opening of mPTPs and the oxidative stress resulting from formation of reactive oxygen species(ROS).Several signaling cardioprotective pathways are activated by stimuli such as preconditioning and postconditioning,obtained with brief intermittent ischemia or with pharmacological agents.These pathways converge on a common target,the mitochondria,to preserve their function after ischemia/reperfusion.The present review discusses the role of mitochondria in cardioprotection,especially the involvement of adenosine triphosphate-dependent potassium channels,ROS signaling,and the mPTP.Ischemic postconditioning has emerged as a new way to target the mitochondria,and to drastically reduce lethal reperfusion injury.Several clinical studies using ischemic postconditioning during angioplasty now support its protective effects,and an interesting alternative is pharmacological postconditioning.In fact ischemic postconditioning and the mPTP desensitizer,cyclosporine A,have been shown to induce comparable protection in AMI patients. | Maria-Giulia Perrelli Pasquale Pagliaro Claudia Penna | 2011 | World Journal of Cardiology2011，3，6： | 64 |
| 2 | Relationship between plasma D(-)-lactate and intestinal damage after severe injuries in rats显示文摘AIM To explore the kinetic changes in plasma D (-)lactate and lipopolysaccharide ( LPS ) levels, and investigate whether D (-)-lactate could be used as a marker of intestinal injury in rats following gut ischemia/reperfusion, burn, and acute necrotizing pancreatitis (ANP).METHODS Three models were developed in rats:gut ischemia/reperfusion obtained by one hour of superior severe burn injury created by 30% of total body surface induced by continuous inverse infusion of sodium taurocholate and trypsin into main pancreatic duct.Plasma levels of D( - )-lactate in systemic circulation and LPS in portal circulation were measured by enzymaticspectrophotometric method and limulus amebocyte lysate (LAL) test kit, respectively. Tissue samples of intestine were taken for histological analysis.RESULTS One hour gut ischemia followed by reperfusion injuries resulted in a significant elevation in plasma D( - )lactate and LPS levels, and there was a significant correlation between the plasma D( - )-lactate and LPS (r =0.719, P<0.05). The plasma concentrations of D(-)lactate and LPS increased significantly at 6 h postburn,and there was also a remarkable correlation between them (r = 0.877, P < 0.01). D ( - )-lactate and LPS levels elevated significantly at 2 h after ANP, with a similar significant correlation between the two levels (r-0.798,P < 0.01 ). The desquamation of intestine villi and infiltration of inflammatory cells in the lamina propria were observed in all groups.CONCLUSION The changes of plasma D( - )-lactate levels in systemic blood paralleled with LPS levels in the portal vein blood. The measurement of plasma D (-)-lactate level may be a useful marker to assess the intestinal injury and to monitor an increase of intestinal permeability and endotoxemia following severe injuries in early stage. | Xiao-Qing Sun Xiao-Bing Fu Rong-Zhan Yi Lü Qun Deng Xiao-Guo Jian Zhi-Yong Sheng Bum Institute, 304~(th)Hospital,Beijing 100037,China Department of General Surgery,Chinese PLA 304 Hospital,Beijing 100037,China | 2001 | World Journal of Gastroenterology2001，7，4： | 56 |
| 3 | Changes of plasma D(-) -lactate, diamine oxidase and endotoxin in patients with liver cirrhosis显示文摘BACKGROUND: Plasma D(-)-lactate and diamine oxidase (DAO) can reflect patients’ intestinal mucosal condition. We evaluated the changes of plasma D (-)-lactate, DAO and endotoxin activities and their significance in patients with liver cirrhosis. METHODS: Fifty liver cirrhosis patients were enrolled into experimental group and 30 healthy people into control group. The plasma levels of D(-)-lactate, DAO and endo- toxin were detected spectrophotographically. RESULTS: The level of D(-)-lactate was significantly high- er in the experimental group than that in the control group (P<0.01). Significant differences of D (-)-lactate levels were observed in Child-Pugh subgroups of the experimen- tal group (P <0. 01). The level of DAO was significantly higher in the experimental group than that in the control group (P <0.01), but the level of DAO in Child-Pugh sub- group C was significantly lower than that in Child-Pugh subgroup B (P<0.01). The level of endotoxin was signifi- cantly increased in the experimental group except Child Pugh subgroup A (P<0.01). The plasma levels of D(-) lactate, DAO and endotoxin were positively correlated with each other (P<0.01). CONCLUSIONS: The data suggest that both plasma D(-) lactate and DAO activity are sensitive markers for early diagnosis of gut failure and endotoxemia in patients with liver cirrhosis. The impairment of intestinal barrier func- tion may be one of the critical reasons for deterioration of liver cirrhosis. | Peng Ruan, Zuo-Jiong Gong and Quan-Rong Zhang Wuhan, China Department of Infectious Diseases, Renmin Hospital Wuhan University Medical College, Wuhan 430060 , China | 2004 | Hepatobiliary & Pancreatic Diseases International2004，3，1： | 31 |
| 4 | Recent progress of nanomaterials for microwave absorption显示文摘Microwave absorbing materials have received considerable interest over the years for their applications in stealth,communications,and information processing technologies.These materials often require functionalization at the nanoscale so to achieve desirable dielectric and magnetic properties which induce interaction with incident electromagnetic radiation.This article presents a comprehensive review on the recent research progress of nanomaterials for microwave absorption,including the basic mechanism of microwave absorption(e.g.,dielectric loss,magnetic loss,dielectric/magnetic loss coupling),measurement principle(e.g.,fundamentals of analysis,performance evaluation,common interaction pathways:Debye relaxation,Eddy current loss,natural resonance,size and shape factors),and the advances and performance review in microwave absorption(e.g.,absorption bandwidth,reflection loss values,absorption peak position)using various nanomaterials,such as carbon nanotubes,carbon fibers,graphenes,oxides,sulfides,phosphides,carbides,polymers and metal organic frameworks.Overall,this article not only provides an introduction on the fundamentals of microwave absorption research,but also presents a timely update on the research progress of the microwave absorption performance of various nanomaterials. | Michael Green Xiaobo Chen | 2019 | Journal of Materiomics2019，5，4： | 33 |
| 5 | Geologic characteristics, controlling factors and hydrocarbon accumulation mechanisms of China’s Large Gas Provinces of low porosity and permeability显示文摘Based on the analysis of the geological characteristics and controlling factors, we analyzed the formation mechanism of different types of gas reservoirs. The main characteristics of gas provinces with low porosity and permeability are mainly as follows: large area, low abundance, small gas pools and large gas provinces; widely distributed excellent hydrocarbon source rocks with closely contacted source-reservoir-cap association; development mainly in large continental depressions or in paralic shallow-river delta systems; many kinds of traps coexisting in large areas, dominantly para-layered lithologic, digenetic and capillary pressure traps; double fluid flow mechanisms of Darcy flow and non-Darcy flow; complicated gas and water relations; and having the resource distribution of highly productive 'sweet spots', banding concentration, and macroscopically large areas integrated. The main controlling factors of large sandstone gas provinces with low porosity and permeability are stable dynamic backgrounds and gentle structural frameworks which control the extensive distribution of alternate (interbedded) sandstones and mudstones; weak hydropower of large gentle lake basins controlling the formation of discontinuous, low porosity and permeability reservoirs in shallow-water deltas; regionally differential diagenesis and no homogeneous digenetic facies controlling the development of favorable reservoirs and digenetic traps; and weak and dispersive reservoir-forming dynamic forces leading to the widely distributed small traps with low abundance. Low porosity and permeability gas provinces with different trap types have different formation mechanisms which include fluid diversion pressure difference interactive mechanism of lithologic-trap gas accumulations, separated differential collection mechanism of digenetic-trap gas accumulations, and the Non-Darcy flow mechanism of capillary-pressure gas accumulations. | ZOU CaiNeng TAO ShiZhen ZHANG XiangXiang HE DongBo ZHOU ChuanMin GAO XiaoHui | 2009 | Science China Earth Sciences2009，52，8： | 22 |
| 6 | Permeability analysis of fractured vuggy porous media based on homogenization theory显示文摘Based on the characteristics of fractured vuggy porous media,a novel mathematical model was proposed to model fluid flow in such media on fine scale,i.e.,the discrete fracture-vug network model.The new model consists of three systems:porous rock system,fracture system,and vug system.The fractures and vugs are embedded in porous rock,and the isolated vugs could be connected via the discrete fracture network.The flow in porous rock and fractures follows Darcy's law,and the vugs system is free fluid region.Using a two-scale homogenization limit theory,we obtained a macroscopic Darcy's law governing the media on coarse scale.The theoretical formula of the equivalent permeability of the fractured vuggy porous media was derived.The model and method of this paper were verified by some numerical examples.At the end the permeability of some fractured vuggy porous media with typical fracture-vug structures was analyzed. | HUANG ZhaoQin,YAO Jun,LI YaJun,WANG ChenChen&LüXinRui College of Petroleum Engineering,China University of Petroleum,Qingdao 266555,China | 2010 | Science China(Technological Sciences)2010，53，3： | 22 |
| 7 | The distribution rule and seepage effect of the fractures in the ultra-low permeability sandstone reservoir in east Gansu Province,Ordos Basin显示文摘To study the impact of the fractures on development in the ultra-low permeability sandstone reservoir of the Yangchang Formation of the Upper Triassic in the Ordos Basin,data on outcrops,cores,slices,well logging and experiments are utilized to analyze the cause of the formation of the fractures,their distribution rules and the control factors and discuss the seepage flow effect of the fractures. In the studied area developed chiefly high-angle tectonic fractures and horizontal bedding fractures,inter-granular fractures and grain boundary fractures as well. Grain boundary fractures and intragranular fractures serve as vital channels linking intragranular pores and intergranular solution pores in the reservoir matrix,thus providing a good connectivity between the pores in the ultra-low perme-ability sandstone reservoir. The formation of fractures and their distribution are influenced by such external and internal factors as the palaeo-tectonic stress field,the reservoir lithological character,the thickness of the rock layer and the anisotropy of a layer. The present-day stress field influences the preservative state of fractures and their seepage flow effect. Under the tec-tonic effect of both the Yanshan and Himalayan periods,in this region four sets of fractures are distributed,respectively assuming the NE-SW,NW-SE,nearly E-W and nearly S-N orientations,but,due to the effect of the rock anisotropy of the rock formation,in some part of it two groups of nearly orthogonal fractures are chiefly distributed. Under the effect of the present-day stress field,the fractures that assume the NE-SW direction have a good connectivity,big apertures,a high permeability and a minimum starting pressure,all of which are main advantages of the seepage fractures in this region. With the development of oilfields,the permeability of the fractures of dif-ferent directions will have a dynamic change. | ZENG LianBo1,GAO ChunYu2,QI JiaFu1,WANG YongKang2,LI Liang2 & QU XueFeng2 1 State Key Laboratory of Petroleum Resource and Prospecting,China University of Petroleum,Beijing 102249,China 2 Changqing Oilfield Branch,PetroChina,Xi’an 163517,China | 2008 | Science China Earth Sciences2008，51，S2： | 22 |
| 8 | Activation of SIRT1 ameliorates LPS-induced lung injury in mice via decreasing endothelial tight junction permeability显示文摘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. | Cui-ping Fu Sheng-yu Hao Xiao-bo Xu Jian Zhou Zi-long Liu Huan Lu Li-min Wang Wei-zhong Jin Shan-qun Li | 2019 | Acta Pharmacologica Sinica2019，40，5： | 22 |
| 9 | Current status and technical challenges of C_(2)storage in coal seams and enhanced coalbed methane recovery:an overview显示文摘In the past two decades,research on C_(2)storage in coal seams and simultaneously enhanced coalbed methane recovery(ECBM)has attracted a lot of attention due to its win–win effect between greenhouse gas(C_(2))emission reduction and coalbed methane recovery enhancement.This paper presents an overview on the current status of research on C_(2)-ECBM in the past two decades,which involves C_(2)storage capacity evaluations,laboratory investigations,modelings and pilot tests.The current status shows that we have made great progress in the ECBM technology study,especially in the understanding of the ECBM mechanisms.However,there still have many technical challenges,such as the definition of unmineable coal seams for C_(2)storage capacity evaluation and storage site characterization,methods for C_(2)injectivity enhancement,etc.The low injectivity of coal seams and injectivity loss with C_(2)injection are the major technique challenges of ECBM.We also search several ways to promote the advancement of ECBM technology in the present stage,such as integrating ECBM with hydraulic fracturing,using a gas mixture instead of pure C_(2)for injection into coal seams and the application of ECBM to underground coal mines. | Xiaochun Li Zhi-ming Fang | 2014 | International Journal of Coal Science & Technology2014，1，1： | 22 |
| 10 | Electroacupuncture improves gut barrier dysfunction in prolonged hemorrhagic shock rats through vagus anti-inflammatory mechanism显示文摘AIM:To investigate whether electroacupuncture(EA)at Zusanli(ST36)prevents intestinal barrier and remote organ dysfunction following prolonged hemorrhagic shock through a vagus anti-inflammatory mechanism.METHODS:Sprague-Dawley rats were subjected to about 45%of total blood volume loss followed by delayed fluid replacement(DFR)with Ringer lactate 3h after hemorrhage.In a first study,rats were randomly divided into six groups:(1)EAN:EA at non-channel acupoints followed by DFR;(2)EA:EA at ST36 after hemorrhage followed by DFR;(3)VGX/EA:vagotomy(VGX)before EA at ST36 and DFR;(4)VGX/EAN:VGX before EAN and DFR;(5)α-bungarotoxin(α-BGT)/EA:intraperitoneal injection ofα-BGT before hemorrhage,followed by EA at ST36 and DFR;and(6)α-BGT/EAN group:α-BGT injection before hemorrhage followed by EAN and DFR.Survival and mean arterial pressure(MAP)were monitored over the next 12 h.In a second study,with the same grouping and treatment,cytokine levels in plasma and intestine,organ parameters,gut injury score,gut permeability to 4 kDa FITC-dextran,and expression and distribution of tight junction protein ZO-1 were evaluated.RESULTS:MAP was significantly lowered after blood loss;EA at ST36 improved the blood pressure at corresponding time points 3 and 12 h after hemorrhage.EA at ST36 reduced tumor necrosis factor-αand interleukin(IL)-6 levels in both plasma and intestine homogenates after blood loss and DFR,while vagotomy or intraperitoneal injection ofα-BGT before EA at ST36reversed its anti-inflammatory effects,and EA at ST36did not influence IL-10 levels in plasma and intestine.EA at ST36 alleviated the injury of intestinal villus,the gut injury score being significantly lower than that of EAN group(1.85±0.33 vs 3.78±0.59,P<0.05).EA at ST36 decreased intestinal permeability to FITCdextran compared with EAN group(856.95 ng/mL±90.65 ng/mL vs 2305.62 ng/mL±278.32 ng/mL,P<0.05).EA at ST36 significantly preserved ZO-1 protein expression and localization at 12 h after hemorrhage.However,EA at non-channel acupoints had no such effect,and abdominal vagotomy andα-BGT treatment could weaken or eliminate the effects of EA at ST36.Besides,EA at ST36 decreased blood aminotransferase,MB isoenzyme of creatine kinase and creatinine vs EAN group at corresponding time points.At the end of 12-h experiment,the survival rate of the EA group was significantly higher than that of the other groups.CONCLUSION:EA at ST36 attenuates the systemic inflammatory response,protects intestinal barrier integrity,improves organ function and survival rate after hemorrhagic shock via activating the cholinergic antiinflammatory mechanism. | Ming-Hua Du Hong-Min Luo Sen Hu Yi Lv Zhi-Long Lin Li Ma | 2013 | World Journal of Gastroenterology2013，19，36： | 21 |
| 11 | Leaching hydrodynamics of weathered elution-deposited rare earth ore显示文摘Both porosity ( φ ) and permeability ( k ) of the weathered elution deposited rare earth ores are basic hydrodynamic parameters for RE leaching. The relationship between k and φ of two typical rare earth ores of South China in the packed bed was investigated by measuring the flow ( Q ) under various leaching pressure difference (Δ p ). The experimental results show that the relationship between k and φ is unique, moreover the relationship between Q and Δ p is in accord with the Darcy’s law. The effects of the type of ores, the leaching reagents and its concentration, the granule ore size on the leaching permeability have also been investigated. It is demonstrated that k H (for heavy RE ore, k H=35.98?mm 2)> k M H (for middle heavy RE ore, k M H =28.50?mm 2), whereas k (NH 4NO 3)> k (NH 4Cl)> k [(NH 4) 2SO 4], and the k value increases with increasing leaching reagents concentration and granule ore size( k 0.60~0.75?mm =99.96?mm 2, k 0.125~0.60?mm =11.83?mm 2, k 0.074~0.125?mm =0.84?mm 2). [ | 田君 池汝安 朱国才 徐盛明 邱欣 张志庚 | 2001 | 中国有色金属学会会刊:英文版2001，11，3： | 19 |
| 12 | 高渗透分布式发电对配电网电压质量的影响研究显示文摘针对高渗透率下的分布式发电影响配电网电压质量的问题,研究了一种带高渗透分布式发电的配电网的典型结构并建立了仿真模型。仿真分析结果表明,高渗透下分布式发电系统带来的能量流波动是中低压配电网中引起电压质量问题的根本原因。基于仿真分析的结果,提出了通过逆变型微源注入功率调整电压的方法,采用适当的控制策略有效改善了配电网的电压质量,达到了预期的控制效果。 | 冯兴田 韦统振 孔令志 | 2010 | 水电能源科学2010，28，9： | 19 |
| 13 | Non-invasive assessment of barrier integrity and function of the human gut显示文摘Over the past decades evidence has been accumulating that intestinal barrier integrity loss plays a key role in the development and perpetuation of a variety of disease states including inflammatory bowel disease and celiac disease,and is a key player in the onset of sepsis and multiple organ failure in situations of intestinal hypoperfusion,including trauma and major surgery.Insight into gut barrier integrity and function loss is important to improve our knowledge on disease etiology and pathophysiology and contributes to early detection and/or secondary prevention of disease.A variety of tests have been developed to assess intestinal epithelial cell damage,intestinal tight junction status and consequences of intestinal barrier integrity loss,i.e.increased intestinal permeability.This review discusses currently available methods for evaluating loss of human intestinal barrier integrity and function. | Joep Grootjans Geertje Thuijls Froukje Verdam Joep PM Derikx Kaatje Lenaerts Wim A Buurman | 2010 | World Journal of Gastrointestinal Surgery2010，2，3： | 18 |
| 14 | Oral 99mTc-DTPA simultaneous determina-tion of duodenobiliary reflux and intestinal permeability in patients after choledocholithotomy plus T-tube drainage显示文摘BACKGROUND: The high choledocholithiasis recurrence rate after choledocholithotomy plus T-tube drainage is related to biliary bacterial infection. These bacteria are from the intestine, either via the major duodenal papilla, or the penetrating intestinal mucosa. It is therefore possible that duodenobiliary reflux and increased intestinal permeability exist in patients who have undergone choledocholithotomy. This study was undertaken to find the evidence of duodenobiliary reflux and to assess intestinal permeability in these patients. METHODS: Twenty-one patients who underwent choledocholithotomy plus T-tube drainage 2 months ago, and 11 healthy volunteers (controls) took orally 185MBq of 99mTc-DTPA. The patients’ bile was collected in the next 2 hours via a T-tube and the 99mTc-DTPA radioactivity in the bile was counted. Intestinal permeability was evaluated by measuring the 24-hour urinary excretion rate of ingested 99m Tc-DTPA in both patients and controls. RESULTS: In 6 of the 21 patients, radioactivity in the bile was detected. The intestinal permeability was significantly higher in patients (11.45% ±6.16% ) than that in controls (3.61%±1.63%, t=3.28, P<0.05). CONCLUSIONS: Duodenobiliary reflux exists in patients who have undergone choledocholithotomy plus T-tube drainage. The intestinal permeability is higher in these patients than in healthy subjects. Duodenobiliary reflux and increased intestinal permeability may be factors of cholelithiasis recurrence. | | 2005 | Hepatobiliary & Pancreatic Diseases International2005，4，4： | 13 |
| 15 | Hyodeoxycholic acid protects the neurovascular unit against oxygen-glucose deprivation and reoxygenation-induced injury in vitro显示文摘Calculus bovis is commonly used for the treatment of stroke in traditional Chinese medicine. Hyodeoxycholic acid(HDCA) is a bioactive compound extracted from calculus bovis. When combined with cholic acid, baicalin and jas-minoidin, HDCA prevents hypoxia-reoxygenation-induced brain injury by suppressing endoplasmic reticulum stress-mediated apoptotic signaling. However, the effects of HDCA in ischemic stroke injury have not yet been studied. Neurovascular unit(NVU) dysfunction occurs in ischemic stroke. Therefore, in this study, we investigated the effects of HDCA on the NVU under ischemic conditions in vitro. We co-cultured primary brain microvascular endothelial cells, neurons and astrocytes using a transwell chamber co-culture system. The NVU was pre-treated with 10.16 or 2.54 μg/mL HDCA for 24 hours before exposure to oxygen-glucose deprivation for 1 hour. The cell counting kit-8 assay was used to detect cell activity. Flow cytometry and terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling were used to assess apoptosis. Enzyme-linked immunosorbent assay was used to measure the expression levels of inflammatory cytokines, including interleukin-1β, interleukin-6 and tumor necrosis factor-α, and neurotrophic factors, including brain-derived neurotrophic factor and glial cell line-derived neurotrophic factor. Oxidative stress-related factors, such as superoxide dismutase, nitric oxide, malondialdehyde and γ-glutamyltransferase, were measured using kits. Pretreatment with HDCA significantly decreased blood-brain barrier permeability and neuronal apoptosis, significantly increased transendothelial electrical resistance and γ-glutamyltransferase activity, attenuated oxidative stress damage and the release of inflammatory cytokines, and increased brain-derived neurotrophic factor and glial cell line-derived neurotrophic factor expression. Our findings suggest that HDCA maintains NVU morphological integrity and function by modulating inflammation, oxidation stress, apoptosis, and the expression of neurotrophic factors. Therefore, HDCA may have therapeutic potential in the clinical management of ischemic stroke. This study was approved by the Ethics Committee of Experimental Animals of Beijing University of Chinese Medicine(approval No. BUCM-3-2016040201-2003) in April 2016. | Chang-Xiang Li Xue-Qian Wang Fa-Feng Cheng Xin Yan Juan Luo Qing-Guo Wang | 2019 | Neural Regeneration Research2019，14，11： | 13 |
| 16 | Guiding-controlling technology of coal seam hydraulic fracturing fractures extension显示文摘Aiming at the uncontrollable problem of extension direction of coal seam hydraulic fracturing,this study analyzed the course of fractures variation around the boreholes in process of hydraulic fracturing,and carried out the numerical simulations to investigate the effect of artificial predetermined fractures on stress distribution around fractured holes.The simulation results show that partial coal mass occurs relatively strong shear failure and forms weak surfaces,and then fractures extended along the desired direction while predetermined fractures changed stress distribution.Directional fracturing makes the fractures link up and the pressure on coal mass is relieved within fractured regions.Combining deep hole controlling blasting with hydraulic fracturing was proposed to realize the extension guiding-controlling technology of coal seam fractures.Industrial experiments prove that this technology can avoid local stress concentration and dramatically widen the pressure relief scope of deep hole controlling blasting.The permeability of fractured coal seam increased significantly,and gas extraction was greatly improved.Besides,regional pressure relief and permeability increase was achieved in this study. | Zhai Cheng Li Min Sun Chen Zhang Jianguo Yang Wei Li Quangui | 2012 | International Journal of Mining Science and Technology2012，22，6： | 12 |
| 17 | Polydatin prevents the induction of secondary brain injury after traumatic brain injury by protecting neuronal mitochondria显示文摘Polydatin is thought to protect mitochondria in different cell types in various diseases.Mitochondrial dysfunction is a major contributing factor in secondary brain injury resulting from traumatic brain injury.To investigate the protective effect of polydatin after traumatic brain injury,a rat brain injury model of lateral fluid percussion was established to mimic traumatic brain injury insults.Rat models were intraperitoneally injected with polydatin(30 mg/kg)or the SIRT1 activator SRT1720(20 mg/kg,as a positive control to polydatin).At 6 hours post-traumatic brain injury insults,western blot assay was used to detect the expression of SIRT1,endoplasmic reticulum stress related proteins and p38 phosphorylation in cerebral cortex on the injured side.Flow cytometry was used to analyze neuronal mitochondrial superoxide,mitochondrial membrane potential and mitochondrial permeability transition pore opened.Ultrastructural damage in neuronal mitochondria was measured by transmission electron microscopy.Our results showed that after treatment with polydatin,release of reactive oxygen species in neuronal mitochondria was markedly reduced;swelling of mitochondria was alleviated;mitochondrial membrane potential was maintained;mitochondrial permeability transition pore opened.Also endoplasmic reticulum stress related proteins were inhibited,including the activation of p-PERK,spliced XBP-1 and cleaved ATF6.SIRT1 expression and activity were increased;p38 phosphorylation and cleaved caspase-9/3 activation were inhibited.Neurological scores of treated rats were increased and the mortality was reduced compared with the rats only subjected to traumatic brain injury.These results indicated that polydatin protectrd rats from the consequences of traumatic brain injury and exerted a protective effect on neuronal mitochondria.The mechanisms may be linked to increased SIRT1 expression and activity,which inhibits the p38 phosphorylation-mediated mitochondrial apoptotic pathway.This study was approved by the Animal Care and Use Committee of the Southern Medical University,China(approval number:L2016113)on January 1,2016. | Li Li Hong-Ping Tan Cheng-Yong Liu Lin-Tao Yu Da-Nian Wei Zi-Chen Zhang Kui Lu Ke-Sen Zhao Marc Maegele Dao-Zhang Cai Zheng-Tao Gu | 2019 | Neural Regeneration Research2019，14，9： | 12 |
| 18 | Ethyl pyruvate prevents inflammatory factors release and decreases intestinal permeability in rats with D-galactosamine-induced acute liver failure显示文摘BACKGROUND: The pathogenesis and progression of acute liver failure (ALF) are closely associated with intestinal endotoxemia because of the high permeability of the intestinal wall. Treatment with ethyl pyruvate (EP) has been shown to protect liver failure effectively. The current study aimed to explore the relationship between proinflammatory cytokines and intestinal permeability, and to investigate whether EP administration might prevent the release of multiple proinflammatory cytokines and decrease intestinal permeability and therefore, protect the liver from injury. METHODS: The ALF model was induced by D-galactosamine in rats. The rats were randomly divided into control (saline i.p.), model (D-galactosamine, 1.2 g/kg, i.p.), prevention [EP injection (40 mg/kg) 2 hours ahead of D-galactosamine] and treatment groups (EP injection 2 hours after D-galactosamine) Samples were obtained at 12 and 24 hours after ALF induction respectively. The histology of liver and intestinal tissue was accessed. Serum alanine aminotransferase, endotoxin, D(-) lactate, diamine oxidase (DAO), tumor necrosis factor-alpha (TNF-α), interferon-γ (IFN-γ) and high mobility group box-1 (HMGB1) were evaluated. The survival of rats was also recorded. RESULTS: The rats in model group showed severe damage to liver tissue and intestinal mucosa 12 and 24 hours after ALF induction. EP significantly improved liver or intestinal injury In addition, serum endotoxin, D(-)-lactate, DAO, TNF-α IFN-γ and HMGB1 levels were significantly increased in the model group compared with the control group. There was a positive correlation between intestinal permeability andproinflammatory cytokines. EP significantly reduced serum endotoxin, D(-)-lactate, DAO, TNF-α, IFN-γ and HMGB1 levels. The median survival time was significantly prolonged in both prevention and treatment groups (126 and 120 hours compared with 54 hours in the model group). CONCLUSIONS: EP has protective and therapeutic effects on intestinal mucosa. EP decreases intestinal permeability, and inhibits the release of multiple proinflammatory cytokines in rats with ALF. | Li-Kun Wang Lu-Wen Wang Xun Li Xiao-Qun Han Zuo-Jiong Gong | 2013 | Hepatobiliary & Pancreatic Diseases International2013，12，2： | 12 |
| 19 | Development of sintered Ni-Cu wicks for loop heat pipes显示文摘The present study fabricated a series of capillary wicks for loop heat pipes(LHPs),using two different methods,the cold-pressing sintering and direct loose sintering,and experimentally investigated the effect of different methods,compositions and sintering parameters on their properties in terms of porosity,permeability and pore radius.Porosity and pore radius were measured by the Archimedes method and Scanning Electron Microscope(SEM),respectively.Permeability of the wicks was compared by calculation using empirical equation.Results show that capillary wicks were successfully fabricated by using two different methods;the optimal capillary wick was found to be sintered at 650℃ for 30min,using direct loose sintering technique,with 90% nickel and 10% copper.The wicks could reach the porosity of 70.07% and the permeability of 10-13m2 order,with mean pore radius of 0.54μm. | XIN GongMing CUI KeHang ZOU Yong CHENG Lin | 2009 | Science China(Technological Sciences)2009，52，6： | 11 |
| 20 | Microwave electromagnetic and absorbing properties of Dy^(3+) doped MnZn ferrites显示文摘Dy3+ doped Mn-Zn ferrites Mn0.3Zn0.7Fe2-xDyxO4(x=0,0.01,0.02,0.03,0.04)were prepared by the conventional solid-state reaction.The crystal structure,surface morphology and electromagnetic properties of the calcined samples were characterized by X-ray diffraction analysis(XRD),scanning electron microscopy(SEM) and network analyzer(Agilent 8722ET).All the XRD patterns showed the single phase of the spinel-type ferrite without other intermediate when x≤0.03.The average crystallite size was about 44?56 nm.The microwave electromagnetic properties of the samples were studied at the frequency range from 2 GHz to 18 GHz.It was shown that small amounts of Dy3+ substitution could adjust microwave electromagnetic parameters magically.The tan δ exhibited a maximal peak when x=0.03,and the peak value was 0.56.It indicated that the microwave electromagnetic loss properties were excellent when x=0.03.Furthermore,the reasons were also discussed using electromagnetic theory.The reflection loss(RL) increased with the Dy3+ content when x<0.04.The Mn0.3Zn0.7Fe1.97Dy0.03O4 ferrite displayed excellent microwave absorption properties.The frequency(with respect to-10 dB) started from 11.9 GHz,and the bandwidth reached about 3.5 GHz.The peak value of RL was about-20.5 dB at a matching thickness of 2.7 mm. | 宋杰 王丽熙 许乃岑 张其土 | 2010 | Journal of Rare Earths2010，28，3： | 11 |
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