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    题名 作者 年代 出处 被引量
1Time range of Mesozoic tectonic regime inversion in eastern North China Block显示文摘An important tectonic inversion took place in eastern North China Block(NCB) during Mesozoic, which caused a great lithosphere thinning, reconstruction of basin-range series, powerful interaction between mantle and crust, a vast granitic intrusion and volcanism, and large-scale metallogenic explosion. The time range of the Mesozoic tectonic regime inversion in the eastern North China Block is one of the key issues to understand mechanism of tectonic regime inversion. Our updated results for recognizing the time range are mainly obtained from the following aspects: structural analyses along northern and southern margins of the NCB and within the NCB for revealing tectonic inversion from compression to extension and structural striking from ~EW to NNE; geothermic analyses of the eastern sedimental basins for a great change of thermal history and regime; basin analysis for basin inversion from compression to extension and basin migration from ~EW to NNE; petrological and geochemical studies of volcanic rocks and lowermost crust xenoliths for recognizing peak period of mantle upwelling and intense interaction between mantle and crust, and main metallogenic epoch. All the studies of the above give the same time range from~150-140 Ma to ~110-100Ma, peaking at ~120 Ma.ZHAI Mingguo ZHU Rixiang LIU Jianming MENG Qingren HOU Quanlin HU Shengbiao LIU Wei LI Zhong ZHANG Hongfu ZHANG Huafeng 2004Science China Earth Sciences2004,47,2:89
2Geodynamic settings of Mesozoic large-scale mineralization in North China and adjacent areas——Implication from the highly precise and accurate ages of metal deposits显示文摘Based on the summary of the highly precise datings of the metal deposits and related granitic rocks in North China craton and adjacent areas, such as the molybdenite Re-Os datings, 40Ar-39Ar datings of mica, K-feldspar and quartz, some Rb-Sr isochrons, and the SHRIMP zircon U-Pb dating and single grain zircon U-Pb dating, we suggest that the large-scale mineralization in North China craton and adjacent areas take place in three periods of 200-160Ma, 140Ma, and 130-110Ma. Their corresponding geodynamic settings are proposed to be the collision orogenic process, transformation of the tectonic regime, and delamination of the lithosphere, respectively, in light of analyzing the Mesozoic geodynamic evolution in the North China craton.毛景文 王义天 张作衡 余金杰 牛宝贵 2003Science China Earth Sciences2003,46,8:133
3大陆造山运动:从大洋俯冲到大陆俯冲、碰撞、折返的时限--以北祁连山、柴北缘为例显示文摘北祁连山和柴北缘是典型的早古生代大陆造山带,分别发育有北祁连山大洋型俯冲缝合带和柴北缘大陆型俯冲碰撞带。作为早古生代大洋冷俯冲的典型代表,北祁连山经历了从新元古代-寒武纪大洋扩张、奥陶纪俯冲和闭合及早泥盆世隆升造山的过程。高压变质岩变质年龄为490~440Ma,证明古祁连洋经历了至少50m.y.的俯冲过程。柴北缘超高压变质带是大陆深俯冲的结果,岩石学、地球化学和同位素年代学表明,柴北缘超高压变质带中榴辉岩的原岩分别来自洋壳和陆壳两种环境。高压/超高压变质的蛇绿岩原岩的年龄为517±11Ma,与祁连山蛇绿岩年龄一致。榴辉岩早期的变质年龄为443~473Ma,与祁连山高压变质年龄一致,代表大洋地壳俯冲的时代,而柯石英片麻岩和石榴橄榄岩所限定的超高压变质时代为420~426Ma,代表大陆俯冲的年龄。从大洋俯冲结束到大陆俯冲最大深度的转换时间最少需要20m.y.。自420Ma起,俯冲的大洋岩石圈与跟随俯冲的大陆岩石圈断离,大陆地壳开始折返,发生隆升和造山。北祁连山和柴北缘两个不同类型的高压-超高压变质带反映了早古生代从大洋俯冲到大陆俯冲、隆升折返的造山过程。宋述光 牛耀龄 张立飞 张贵宾 2009岩石学报2009,25,9:99
4贺兰山孔兹岩系的变质时代及其对华北克拉通西部陆块演化的制约显示文摘贺兰山孔兹岩系作为华北克拉通西部孔兹岩带的重要组成部分,其变质时代问题一直悬而未决。利用SHRIMP锆石U-Pb定年技术,对贺兰山孔兹岩系中3个代表性富铝片麻岩(石榴堇青钾长片麻岩、石榴堇青二长片麻岩与石榴黑云斜长片麻岩)样品进行了精确定年。发现这3种岩石虽处不同层位,但其碎屑锆石年龄却非常集中,各测点^(207)Pb/^(206)Pb年龄总体变化在2.0~2.1Ga之间,加权平均年龄则在2017~2040Ma之间。这些碎屑锆石都具有岩浆结构特征,反映当时曾存在大规模花岗质岩浆活动,所成岩体为孔兹岩系沉积提供了充足物源。另有少量大于2.5Ga的碎屑锆石(2520~2949Ma),表明本区存在太古代岩浆活动记录。本区石榴堇青二长片麻岩中发育典型的变质增生锆石,其成因很可能与黑云母的脱水熔融反应有关。利用该锆石确定贺兰山孔兹岩系的变质时代为1950±8Ma。该时代与东部大青山、乌拉山孔兹岩系变质时代相同,表明华北克拉通西部的阴山地块与鄂尔多斯地块大体是以平行的方式正面拼贴到一起的。周喜文 耿元生 2009岩石学报2009,25,8:55
5Entransy dissipation minimization for liquid-solid phase change processes显示文摘The liquid-solid phase change process of a simple one-dimensional slab is studied in this paper.By taking entransy dissipation minimization as optimization objective,the optimal external reservoir temperature profiles are derived by using optimal control theory under the condition of a fixed freezing or melting time.The entransy dissipation corresponding to the optimal heat exchange strategies of minimum entransy dissipation is 8/9 of that corresponding to constant reservoir temperature operations,which is independent of all system parameters.The obtained results for entransy dissipation minimization are also compared with those obtained for the optimal heat exchange strategies of minimum entropy generation and constant reservoir temperature operations by numerical examples.The obtained results can provide some theoretical guidelines for the choice of optimal cooling or heating strategy in practical liquid-solid phase change processes.XIA ShaoJun,CHEN LinGen & SUN FengRui Postgraduate School,Naval University of Engineering,Wuhan 430033,China 2010Science China(Technological Sciences)2010,53,4:41
6^(40)Ar-^(39)Ar dating and geological implication of auriferous altered rocks from the middle-deep section of Q875 gold-quartz vein in Xiaoqinling area, Henan,China显示文摘The 40Ar-39Ar age method is employed in this work to analyze the auriferous altered rocks from the middle-deep section of the Q875 gold-quartz vein in the Xiao-qinling area, and the results show that the main gold deposition of the Q875 occurred in ca. 128-126 Ma. As a typical gold-bearing quartz vein in this gold-rich area, the age data obtained from the Q875 also constrain on the metallogenic time of the lode gold deposits developed in the same geological settings. This geochronological study supplies new evidence for further understanding the timing of gold mineralization, the genesis of gold deposits and the geodynamic settings in Xiaoqinling area.WANG Yitian, MAO Jingwen, LU Xinxiang & YE AnwangInstitute of Mineral Resources, Chinese Academy of Geological Sciences, Beijing 100037, China Institute of Geological Sciences, Henan Province, Zhengzhou 450053, China Lingbao Bureau of Geology and Mineral 2002Chinese Science Bulletin2002,47,20:36
7太行山南段符山高镁闪长岩的成因——拆沉陆壳物质熔融的熔体与地幔橄榄岩反应的结果显示文摘本文对太行山南段符山高镁闪长岩进行了年代学与地球化学研究,结合其中地幔橄榄岩包体的研究,对符山高镁闪长岩的成因和中生代岩石圈地幔的性质进行了探讨。研究表明,符山闪长岩体是由一套含橄榄石角闪闪长岩-角闪闪长岩-闪长岩构成。含橄榄岩包体的寄主岩——角闪闪长岩中的锆石可划分为两种:一是代表寄主岩浆结晶的锆石:内部结构均匀、呈条带状吸收、自形-半自形晶形,具有较高的Th/U比值(1.10~4.08),其^(206)Pb/^(238)U年龄介于123~128Ma之间,12个点的加权平均值为125±1Ma,这表明岩体的形成时代为早白垩世;二是捕获或继承锆石:具有核边结构、吸收程度不均匀、呈浑圆状和自形-半自形两种,它们的Th/U比值介于0.32~2.03之间,构成了3组^(207)Pb/^(206)Pb加权平均年龄:2503±11Ma、2181±26Ma和1778±36Ma。该类岩石的SiO_2和MgO含量分别介于56.69%~59.21%和3.60%~6.33%之间;且以高Mg~#(0.51~0.64)、富Na(Na_2O/K_2O大于1)、高Cr(93.1×10^(-6)~420×10^(-6))、Ni(35.1×10^(-6)~137×10^(-6))为特征。该类岩石强烈富集轻稀土元素和大离子亲石元素、明显亏损高场强元素,(^(87)Sr/^(86)Sr)_i、ε_(Nd)(t)值和(^(206)Pb/^(204)Pb)_i分别变化于0.70581~0.70641、-8.30~-16.56和17.052~17.512之间。综合上述特征,同时结合地慢橄榄岩包体的特征和古元古代捕获锆石的大量存在,认为符山高镁闪长岩的原始岩浆起源于拆沉陆壳物质的部分熔融,其后经历了与地幔橄榄岩的反应过程。许文良 杨德彬 裴福萍 于洋 2009岩石学报2009,25,8:39
8Max-Min Adaptive Ant Colony Optimization Approach to Multi-UAVs Coordinated Trajectory Replanning in Dynamic and Uncertain Environments显示文摘Multiple Uninhabited Aerial Vehicles (multi-UAVs) coordinated trajectory replanning is one of the most complicatedglobal optimum problems in multi-UAVs coordinated control. Based on the construction of the basic model of multi-UAVscoordinated trajectory replanning, which includes problem description, threat modeling, constraint conditions, coordinatedfunction and coordination mechanism, a novel Max-Min adaptive Ant Colony Optimization (ACO) approach is presented indetail. In view of the characteristics of multi-UAVs coordinated trajectory replanning in dynamic and uncertain environments,the minimum and maximum pheromone trails in ACO are set to enhance the searching capability, and the point pheromone isadopted to achieve the collision avoidance between UAVs at the trajectory planner layer. Considering the simultaneous arrivaland the air-space collision avoidance, an Estimated Time of Arrival (ETA) is decided first. Then the trajectory and flight velocityof each UAV are determined. Simulation experiments are performed under the complicated combating environment containingsome static threats and popup threats. The results demonstrate the feasibility and the effectiveness of the proposed approach.Hai-bin Duan,Xiang-yin Zhang,Jiang Wu,Guan-jun MaSchool of Automation Science and Electrical Engineering,Beihang University,Beijing 100191,P.R.China 2009Journal of Bionic Engineering2009,6,2:33
9Effect of amitriptyline on gastrointestinal function and brain-gut peptides: A double-blind trial显示文摘AIM: To study the effects of low-dose amitriptyline (AMT) on gastrointestinal function and brain-gut peptides in healthy Chinese volunteers. METHODS: This was a double-blind, randomised, placebo-controlled, two-period cross-over trial. Twentyeight healthy volunteers were randomised and administered 1-wk treatments of AMT (12.5 mg tid) or placebo. Before and during the final two days of treatment, gastric emptying, proximal gastric accommodation and visceral sensitivity were measured by drinkingultrasonography test; the orocecal transit time (OCTT) was measured by lactulose hydrogen breath test, and fasting blood was collected. Plasma levels of ghrelin, motilin and neuropeptide Y (NPY) were measured by enzyme-linked immunosorbent assay kits.RESULTS: AMT slowed the OCTT (109.2 ± 29.68 min vs 96.61 ± 23.9 min, P = 0.004) but did not affect liquid gastric emptying and had no effect on proximal gastric accommodation. AMT resulted in decreases in the visual analogue scale (VAS) for difficulty in drinking 600 and 800 mL of water (3.57 ± 0.94 vs 2.98 ± 0.85, 5.57 ± 0.82 vs 4.57 ± 0.98, P < 0.01 for both), although it had no significant effect on the VAS for difficulty in drinking 200 mL and 400 mL of water. AMT significantly increased the plasma ghrelin level (442.87 ± 176.79 pg/mL vs 526.87 ± 158.44 pg/mL, P = 0.04) and the neuropeptide-Y level (890.15 ± 131.46 pg/mL vs 965.64 ± 165.63 pg/mL, P = 0.03), whereas it had no effect on the MTL level. CONCLUSION: Low-dose AMT could slow OCTT, make the stomach less sensitive and increase the plasma levels of ghrelin and NPY. Thus, we recommend the use of low-dose AMT for functional gastrointestinal disorders.Wei Huang Shu-Man Jiang Lin Jia Le-Qing You Yao-Xing Huang Yan-Mei Gong Gui-Qin Wang 2013World Journal of Gastroenterology2013,19,26:31
10TIMING OF COLLISION BETWEEN THE NORTH AND SOUTH CHINA BLOCKS——THE Sm-Nd ISOTOPIC AGE EVIDENCE显示文摘Sm-Nd isotopic ages for C-type eclogite (243.9±5.6 Ma) and mafic and ultramafic rocks(230.6±30.7 Ma and 402.6±17.4 Ma) from the Qinling-Dabieshan orogenic belt are reported.These ages suggest that at the early Triassic, the North and South China Blocks have beenunited along the Qinling-Dabieshan collision zone, and before the final collision, a se-ries of ophiolite obductions took place successively away from the continental marginduring the Paleozoic.李曙光 S.R.HART 郑双根 刘德良 张国伟 郭安林 1989Science China Chemistry1989,32,11:33
11Convolutional neural networks for time series classification显示文摘Time series classification is an important task in time series data mining, and has attracted great interests and tremendous efforts during last decades. However, it remains a challenging problem due to the nature of time series data: high dimensionality,large in data size and updating continuously. The deep learning techniques are explored to improve the performance of traditional feature-based approaches. Specifically, a novel convolutional neural network(CNN) framework is proposed for time series classification. Different from other feature-based classification approaches,CNN can discover and extract the suitable internal structure to generate deep features of the input time series automatically by using convolution and pooling operations. Two groups of experiments are conducted on simulated data sets and eight groups of experiments are conducted on real-world data sets from different application domains. The final experimental results show that the proposed method outperforms state-of-the-art methods for time series classification in terms of the classification accuracy and noise tolerance.Bendong Zhao Huanzhang Lu Shangfeng Chen Junliang Liu Dongya Wu 2017Journal of Systems Engineering and Electronics2017,28,1:33
12脑梗死溶栓治疗的临床与基础探索显示文摘魏岗之 柏华 2005中华神经科杂志2005,38,4:29
13Differences in symptoms and pre-hospital delay among acute myocardial infarction patients according to ST-segment elevation on electrocardiogram: an analysis of China Acute Myocardial Infarction (CAMI) registry显示文摘Background: Approximately 70% patients with acute myocardial infarction (AMI) presented without ST-segment elevation on electrocardiogram. Patients with non-ST segment elevation myocardial infarction (NSTEMI) often presented with atypical symptoms, which may be related to pre-hospital delay and increased risk of mortality. However, up to date few studies reported detailed symptomatology of NSTEMI, particularly among Asian patients. The objective of this study was to describe and compare symptoms and presenting characteristics of NSTEMI vs. STEMI patients. Methods: We enrolled 21,994 patients diagnosed with AMI from China Acute Myocardial Infarction (CAMI) Registry between January 2013 and September 2014. Patients were divided into 2 groups according to ST-segment elevation: ST-segment elevation (STEMI) group and NSTEMI group. We extracted data on patients' characteristics and detailed symptomatology and compared these variables between two groups. Results: Compared with patients with STEMI (N=16,315), those with NSTEMI (N=5679) were older, more often females and more often have comorbidities. Patients with NSTEMI were less likely to present with persistent chest pain (54.3% vs.71.4%), diaphoresis (48.6% vs.70.0%), radiation pain (26.4% vs.33.8%), and more likely to have chest distress (42.4% vs.38.3%) than STEMI patients (all P<0.0001). Patients with NSTEMI were also had longer time to hospital. In multivariable analysis, NSTEMI was independent predictor of presentation without chest pain (odds ratio: 1.974, 95% confidence interval:1.849-2.107). Conclusions: Patients with NSTEMI were more likely to present with chest distress and pre-hospital patient delay compared with patients with STEMI. It is necessary for both clinicians and patients to learn more about atypical symptoms of NSTEMI in order to rapidly recognize myocardial infarction.Rui Fu Chen-Xi Song Ke-Fei Dou Jin-Gang Yang Hai-Yan Xu Xiao-Jin Gao Qian-Qian Liu Han Xu Yue-Jin Yang 2019Chinese Medical Journal2019,,5:29
14Environmental records of lacustrine sediments in different time scales:Sediment grain size as an example显示文摘Sediment grain size is a conventional proxy of climatic changes. Larger sediment grain size is often interpreted to indicate dry climate during lower lake level while smaller sedi- ment grain size implies wet climate during higher lake level. Through detailed study on sediment grain sizes in Lake Erhai and Lake Chenghai, this paper reveals the different indication signifi- cances of sediment grain sizes in different time scales, different resolution investigations. For long time-scale and low resolution (102a or 103a) studies, larger sediment grain size indicates lower lake level, smaller lake area and drier climate while smaller sediment grain size indicates higher lake level, larger lake area and wetter climate. For short time-scale and high resolution (a or 10a) studies, larger sediment grain size reflects more rainfall and wetter climate while smaller sediment grain size reflects less rainfall and drier climate. Environmental information revealed by lacustrine sediment records is often different in different time scales because of the variance of sedimentation resolution, sampling resolution and dating precision. Therefore, paleoclimate im- plications of environmental proxies in long time-scale and low resolution investigations could not be mechanically applied to short time-scale and high resolution studies. Only after synthetically analyzing the influence manner and extent of all factors on the sediment records in different time scales, can credible conclusions be obtained.CHEN Jing’an1, WAN Guojiang1, David Dian Zhang2, ZHANG Feng1 & HUANG Ronggui1 1. State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550002, China 2. Department of Geography and Geology, University of Hong Kong, Pokfulam Road, Hong Kong, China 2004Science China Earth Sciences2004,47,10:27
15Improving bubble-particle attachment during the flotation of low rank coal by surface modification显示文摘Based on the problems caused by many oxygen-containing functional groups and poor floatability on the surface of low rank coal,the characteristics of low rank coal were analyzed systematically by means of scanning electron microscopy(SEM),X-ray diffraction(XRD)and X-Ray photoelectron spectroscopy(XPS)techniques.The bubble-particle induction time was used to determine the characterization of the bubble-particle attachment,and the bubble-particle attachment of low rank coal modified by soaking the coal samples in an acid or alkaline solution was analyzed.The floatability of the modified coal surface was verified by flotation tests.The results show that the particle size of 0.125–0.074 mm of the coal sample exhibited better bubble-particle attachment characteristics.The small bubble,the larger approach velocity of bubble and the larger bubble deformation were more helpful to enhance the bubbleparticle attachment.For an acid solution,the smaller the p H was and the longer the soaking time was,the better the floatability of the coal sample and the higher the combustible material recovery were.The combustible material recovery of low rank coal was increased to 78.79%by soaking the sample in an acid solution of pH=0 for 180 min.On the contrary there was a best concentration for the alkaline solution.Haishan Hu Ming Li Lulu Li Xiuxiang Tao 2020International Journal of Mining Science and Technology2020,30,2:27
16再论中产阶级:理论、历史与类型学 兼及一种全球化的视野显示文摘The emergence of the middle class was closely related to the appearance of industrial society and its consequential constant changes in the social structure. Karl Marx and other theorists in the same camp were among the earliest scholars who discussed that topic. For a quite long period of time, the debate was mainly focused on the characteristics of the “new middle class.” The middle class, however, has undergone a categorical transformation from the old to the new middle-class, and furthermore, this transformation itself has signified the transition in social patterns from industrial to post-industrial society as well as economic globalization, both of which have contributed to the growth and global expansion of the middle class, having thus fundamentally renovated the middle class.周晓虹 2005社会2005,25,4:26
17社会批判理论之空间转向与历史唯物主义的空间化显示文摘空间生产和资本全球化进程的加速,引发了一系列空间问题和空间现象高速城镇化正在不断侵害公众的空间权益;空间造型也在符号层面展示着意识形态;农地资源迅速消失,全球转移的制造业正在越来越大的空间内造成环境污染和生态破坏;紧密的'世界普遍交往'正在造就一个'地球村',全球的经济体系和政治体系呈现充满风险的空间结构,多元文明之间的对话和对抗正在全球空间展示着多样性格局,地球人甚至对于'外太空'的空间资源的分割和争夺也日益加剧,等等。当人们的生存方式越来越依赖于当代空间的生产方式的时候,人们也日益对自己空间的存在状况所隐藏的风险深表忧虑。来自空间经济学、空间政治学、空间社会学、空间城市学、空间哲学等多学科的关注凸现了当代研究的'空间视域',进而叩响了马克思主义哲学的大门。本刊推出系列文章,以空间生产这一问题为中心,旨在推进关于空间生产问题的多学科交叉研究。胡大平 2007江海学刊2007,,2:25
18The UCR Time Series Archive显示文摘The UCR time series archive–introduced in 2002,has become an important resource in the time series data mining community,with at least one thousand published papers making use of at least one data set from the archive.The original incarnation of the archive had sixteen data sets but since that time,it has gone through periodic expansions.The last expansion took place in the summer of 2015 when the archive grew from 45 to 85 data sets.This paper introduces and will focus on the new data expansion from 85 to 128 data sets.Beyond expanding this valuable resource,this paper offers pragmatic advice to anyone who may wish to evaluate a new algorithm on the archive.Finally,this paper makes a novel and yet actionable claim:of the hundreds of papers that show an improvement over the standard baseline(1-nearest neighbor classification),a fraction might be mis-attributing the reasons for their improvement.Moreover,the improvements claimed by these papers might have been achievable with a much simpler modification,requiring just a few lines of code.Hoang Anh Dau Anthony Bagnall Kaveh Kamgar Chin-Chia Michael Yeh Yan Zhu Shaghayegh Gharghabi Chotirat Ann Ratanamahatana Eamonn Keogh 2019IEEE/CAA Journal of Automatica Sinica2019,6,6:26
19Biliary tract injury caused by different relative warm ischemia time in liver transplantation in rats显示文摘BACKGROUND:There is a controversy over the degree of liver and biliary injury caused by the period of secondary warm ischemia.A liver autotransplantation model was adopted because it excludes the effects of infection and immunological rejection on bile duct injury.This study was undertaken to assess biliary tract injury caused by relative warm ischemia(secondary warm ischemia time in the biliary tract)and reperfusion. METHODS:One hundred and two rats were randomly divided into 5 groups:groupⅠ(control);groupsⅡtoⅤ, relative warm ischemia times of 0 minute,30 minutes,1 hour and 2 hours.In addition to the levels of serum alkaline phosphatase,and total bilirubin,pathomorphology assessment and TUNEL assay were performed to evaluate biliary tract damage. RESULTS:Under the conditions that there were no significant differences in warm ischemia time,cold perfusion time and anhepatic phase,group comparisons showed statistically significant differences.The least injury occurred in groupⅡ(portal vein and hepatic artery reperfused simultaneously)but the most severe injury occurred in groupⅤ(biliary tract relative warm ischemia time 2 hours). CONCLUSIONS:Relative warm ischemia is one of the factors that result in bile duct injury,and the relationship between relative warm ischemia time the bile injury degree is time-dependent.Simultaneous arterial and portal reperfusion is the best choice to avoid the bile duct injury caused by relative warm ischemia.Zhao, Hong-Feng Zhang, Guo-Wei Zhou, Jie Lin, Jian-Hua Cui, Zhong-Lin Li, Xiang-Hong 2009Hepatobiliary & Pancreatic Diseases International2009,8,3:24
20Bridging and downstaging treatments for hepatocellular carcinoma in patients on the waiting list for liver transplantation显示文摘Several therapeutic procedures have been proposed as bridging treatments for patients with hepatocellular carcinoma(HCC)awaiting liver transplantation(LT).The most used treatments include transarterial chemoembolization and radiofrequency ablation.Surgical resection has also been successfully used as a bridging procedure,and LT should be considered a rescue treatment in patients with previous HCC resection who experience tumor recurrence or post-treatment severe decompensation of liver function.The aims of bridging treatments include decreasing the waiting list dropout rate before transplantation,reducing HCC recurrence after transplantation,and improving post-transplant overall survival.To date,no data from prospective randomized studies are available;however,for HCC patients listed for LT within the Milan criteria,prolonging the waiting time over 6-12 mo is a risk factor for tumor spread.Bridging treatments are useful in containing tumor progression and decreasing dropout.Furthermore,the response to pre-LT treatments may represent a surrogate marker of tumor biological aggressiveness and could therefore be evaluated to prioritize HCC candidates for LT.Lastly,although a definitive conclusion can not be reached,the experiences reported to date suggest a positive impact of these treatments on both tumor recurrence and post-transplant patient survival.Advanced HCC may be downstaged to achieve and maintain the current conventional criteria for inclusion in the waiting list for LT.Recent studies have demonstrated that successfully downstaged patients can achieve a 5-year survival rate comparable to that of patients meeting the conventional criteria without requiring downstaging.Maurizio Pompili Giampiero Francica Francesca Romana Ponziani Roberto Iezzi Alfonso Wolfango Avolio 2013World Journal of Gastroenterology2013,19,43:24
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