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1Reconstruction of precipitation variation from tree rings in recent 1000 years in Delingha, Qinghai显示文摘Using seven well-replicated Qilian juniper (Sabina przewalskii Kom.) ring-width chronologies developed at Zongwulong and Shalike Mts. in the northeastern part of the Qaidam Basin annual precipitation from previous July to current June in the recent 1000 years was re- constructed for Delingha. The reconstruction can capture 63.1% of precipitation variance and the equation was stable over time. For the reconstructed precipitation, wet periods occurred in AD1520—1633 and 1933—2001, whereas dry intervals in 1429—1519 and 1634—1741. In ad- dition, the magnitude in precipitation variation was lower before 1430 with about 15 mm, but it increased to 30 mm during the period of 1430 to 1850. After 1850, the precipitation variance de- creased again. In contrast to the increase in temperature, a decrease in annual precipitation was evident since the 1990s. The agreement in low-frequency variation between the reconstruction and the glacier accumulation and particulate content in Dunde ice cores during the recent several hundred years suggested that the precipitation reconstructed in this study was rather reliable, and represented a regional signal. This 1000-year reconstruction could benefit our understanding of climatic variation in decadal to century-scale in this region, and provide basic data to climate models and to prediction of future climate in the 21st century.SHAO Xuemei1, HUANG Lei1, LIU Hongbin2, LIANG Eryuan1, FANG Xiuqi3 & WANG Lili1 1. Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China 2. National Climate Center, Beijing 100081, China 3. Beijing Normal University, Beijing 100875, China 2005Science China Earth Sciences2005,48,7:113
2A Diagnostic Study of the Impact of El Nion on the Precipitation in China显示文摘1.IntroductionEINifioisthemostoutstandinginterannualvariabilityintheocean.Itiswellknownthattheheatsourcedrivingtheatmosphericgeneralcirculationismainlywithinthetropics.EINinooccursinthetropicalPacificandthewarmingoftheoceanduringtheEINinocancoveralar...张人禾 1999Advances in Atmospheric Sciences1999,16,2:86
3基于土地利用变化的京津冀生境质量时空演变显示文摘土地利用变化是全球变化的核心内容,评估土地利用变化引起的生境质量时空分异性是区域生态规划的基础,能为土地利用规划和土地管理政策制定提供科学依据.本文在分析京津冀2000—2010年土地利用变化的基础上,以In VEST模型对生境质量进行总体评估,并基于流域划分,借助剖面线和空间自相关深入分析了生境质量格局时空分异性.结果表明:2000—2010年,研究区主要土地利用变化类型为:耕地转为建设用地、林地和草地间的相互转换及水体转为耕地,这导致景观结构异质性的减弱和破碎度的提升.两时期生境质量格局整体表现为东南部和南部较低、北部和西部较高.其中,东南部和南部2010年生境质量明显下降,发生了一定生境退化乃至丧失现象.各流域生境质量具有明显分段特征,较多样点在2010年出现不同程度退化,但也有部分有所改善.该区生境质量格局空间分布集聚性有所增强.2000年'高高'型生境质量流域空间聚集区为滦河流域和白河流域上游地区,'低低'型聚集区集中在永定河中下游和潮白河流域部分地区.2010年'高高'型和'低低'型空间聚集区在原有基础上各自向西南方向有所扩展.吴健生 曹祺文 石淑芹 黄秀兰 卢志强 2015应用生态学报2015,26,11:146
4Inhibiting effect of antisense oligonucleotides phosphorthioate on gene expression of TIMP-1 in rat liver fibrosis显示文摘AIM To observe the inhibition of antisenseoligonucleotides (asON) phosphorthioate to thetissue inhibitors metalloproteinase-1 (TIMP-1)gene and protein expression in the liver tissue ofimmunologically induced hepatic fibrosis rats.The possibility of reversing hepatic fibrosisthrough gene therapy was observed.METHODS Human serum albumin (HSA) wasused to attack rats, as hepatic fibrosis model, inwhich asONs were used to block the gene andprotein expressing TIMP-1. According to theanalysis of modulator, structure protein, codingseries of TIMP-1 genome, we designed fourdifferent asONs. These asONs were injected intothe hepatic fibrosis models through coccygealvein. The results was observed by RT-PCR formeasuring TIMP-1 mRNA expression,immunohistochemistry and in situ hybridizationfor collagen Ⅰ, Ⅲ, special staining of collagenfiber, and electron microscopic examination.RESULTS Hepatic fibrosis could last within 363days in our modified model. The expressinglevel of TIMP-1 was high during hepatic fibrosisprocess. It has been proved by theimmunohistochemical and the electronmicroscopic examination that the asONphosphorthioate of TIMP-1 could exactly expressin vivo. The effect of colchicine wasdemonstrated to inhibit the expressing level ofmRNA and the content of collagen Ⅰ, Ⅲ in theliver of experimental hepatic fibrosis rats.However, the electron microscopy research andthe pathologic grading of hepatic fibrosisshowed that there was no significant differencebetween the treatment group and the modelgroup (P>0.05).CONCLUSION The experimental rat model ofhepatic fibrosis is one of the preferable modelsto estimate the curative effect of anti-hepaticfibrosis drugs. The asON phosphorthioate ofTIMP-1 could block the gene and proteinexpression of TIMP-1 in the liver of experimentalhepatic fibrosis rats at the mRNA level. It ispossible to reverse hepatic fibrosis, and it isexpected to study a new drug of anti-hepaticfibrosis on the genetic level. Colchicine has verylimited therapeutic effect on hepatic fibrosis,furthermore, its toxicity and side effects areobvious.Qing He Nie Yong Qian Cheng Yu Mei Xie Yong Xing Zhou Yi Zhan Cao The Center of Infectious Disease Diagnosis and Treatment of PLA,Tangdu Hospital,Forth Military Medical University,Xi’an 710038,Shaanxi Province,ChinaDr,Qing He Nie graduated from Qinghai Medical College as a doctor in 1983,got master degree at Beijing 302 Army Hospital in 1993,got doctor degree at the Third Military Medical University in 1998,engaged in postdoctoral research at the Fourth Military Medical University from 1998 to 2000,now an associate professor,specialized in clinical and experimental research of infectious diseases,had more than 90 papers published,coauthor of ten books,first author of one book. 2001World Journal of Gastroenterology2001,7,3:73
5Estimation on the response of glaciers in China to the global warming in the 21st century显示文摘Glaciers in China can be categorized into 3 types, i.e. the maritime (temperate) type, sub-continental (sub-polar) type and extreme Continental (polar) type, which take 22%, 46% and 32% of the total existing glacier area (59 406 km2) respectively. Researches indicate that glaciers of the three types show different response patterns to the global warming. Since the Maxima of the Little Ice Age (the 17th century), air temperature has risen at a magnitude of 1.3℃on average and the glacier area decreased corresponds to 20% of the present total glacier area in western China. it is estimated that air temperature rise in the 2030s, 2070s and 2100s will be of the order of 0.4-1.2, 1.2-2.7 and 2.1-4.0 K in western China. With these scenarios, glaciers in China will suffer from further shrinkage by 12%, 28% and 45% by the 2030s, 2070s and 2100s. The uncertainties may account for 30%-67% in 2100 in China.SHI Yafeng & LIU Shiyin Laboratory of Ice Core and Cold Regions Environment, Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Sciences, Lanzhou 730000, China Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Sciences, Lanzhou 730000, China 2000Chinese Science Bulletin2000,45,7:71
6InDel标记的研究和应用进展显示文摘InDel是指在近缘种或同一物种不同个体之间基因组同一位点的序列发生不同大小核苷酸片段的插入或缺失(insertion-deletion),是同源序列比对产生空位(gap)的现象。InDel在基因组中分布广泛、密度大、数目众多。InDel多态性分子标记是基于插入/缺失位点两侧的序列设计特异引物进行PCR扩增的标记,其本质仍属于长度多态性标记,可利用便捷的电泳平台进行分型。InDel标记准确性高、稳定性好,避免了由于特异性和复杂性导致的后续分析模糊。此外,InDel标记能扩增混合DNA样品和高度降解的微量DNA样品,并进行有效分型。InDel标记目前已开始应用于动植物群体遗传分析、分子辅助育种以及人类法医遗传学、医学诊断等领域。随着位于功能基因上InDel标记的开发,结合染色体步移和基因精细定位,可将这些标记应用于相关物种经济性状的功能基因的筛选,有利于优良基因的进一步开发和利用。杨洁 赫佳 王丹碧 施恩 杨文宇 耿其芳 王中生 2016生物多样性2016,24,2:62
7基于遥感和InVEST模型的白龙江流域景观生物多样性时空格局研究显示文摘以甘肃白龙江流域为例,结合遥感、GIS技术和In VEST模型,从景观地理学角度选取区域生境质量、植物净初级生产力和景观状态指数为评价指标,构建区域景观尺度上生物多样性空间格局综合评估方法,并在栅格像元尺度上开展白龙江流域景观生物多样性时空变化特征分析。结果表明:白龙江流域景观生物多样性空间格局差异显著,其生物多样性高值区主要集中在自然保护区和林业管护区,低值区主要分布在舟曲-武都-文县的白龙江两岸及其以北区域、宕昌县岷江沿岸、高寒稀疏植被区和高山积雪-裸岩区。1990-2010年,流域景观生物多样性较为丰富,整体呈现不断增长的趋势,个别局部区域减弱,其增长区主要体现在生态工程实施区和林业管护区,减少区多分布在人类活动频繁的城乡农耕区和灾害多发区。谢余初 巩杰 张素欣 马学成 胡宝清 2018地理科学2018,38,6:80
8数据挖掘中数据预处理的研究与实现显示文摘数据预处理将原始的真实数据库转换成适于数据挖掘的挖掘数据库 ,为挖掘算法更好的实现以及挖掘结果形象的显示打下了良好的基础。针对结构化数据讨论了数据预处理的两个目标 :消除现实数据库中的数据缺陷 ;为数据挖掘做准备。并在此基础上 。菅志刚 金旭 2004计算机应用研究2004,21,7:54
9基于InVEST模型的甘肃白龙江流域生态系统碳储量及空间格局特征显示文摘区域碳储量的空间分布特征研究可为区域生态系统碳库管理和减排增汇政策制定提供重要科学依据。基于In VEST模型和GIS技术,估算及分析了2010年甘肃白龙江流域碳储量及其空间格局,并探讨了海拔、坡度和坡向对碳储量空间分布的影响。结果表明:甘肃白龙江流域碳总储量为251.57Tg C,平均碳密度为136.46Mg C/hm^2;其中,土壤碳储量为202.20Tg C,植被碳储量为49.37Tg C。碳储量空间分布呈现一定的规律性,碳储量高值区主要集中在流域西北部山区(如迭部县)和白水江南岸(如白水江国家级自然保护区),云杉、冷杉类常绿针叶林的碳总储量最大;低值区多分布在流域东部和东南部(如武都区)、宕昌县东北部等区域。碳储量随海拔高度和坡度的增加呈现先增加后减小的趋势,其高值区主要分布在1500~3500m和25°~40°区段;阴坡和半阴坡区域的碳储量大于阳坡和半阳坡。研究结果可为流域生态系统碳库管理及人类活动管控提供参考。张影 谢余初 齐姗姗 巩杰 张玲玲 2016资源科学2016,38,8:57
10Dynamic changes of typeⅠ,Ⅲand N collagen synthesis and distribution of collagen-producing cells in carbon tetrachloride-induced rat liver fibrosis显示文摘AIM To find out the relationship between the gene transcription of different types ofprocollagen and the deposition of the relevant collagens in the liver tissue and to confirm the types of collagen producing cells in liverfibrogenesis.METHODS Dynamic changes of the expression of α1(Ⅰ ), α1 (Ⅲ ) and α1 (Ⅳ) procollagen mRNAand relevant collagens and the distribution ofcollagen producing cells during liver fibrogenesis of rat induced by CCl4 (20 weeks)were investigated with Northern blot analysis,in situ hybridization and immunohistochemicaltechniques.RESULTS The increased expression of α1 (Ⅲ)procollagen mRNA by Northern blot analysis was the most predominant one among the threemRNAs during fibrogenesis. However, theenhanced expression of al (Ⅳ) procollagenmRNA occurred very early while the expressionof α1 (Ⅰ) mRNA was not enhanced much until themiddle stage of the exPeriment. D6smin (Dm)positive hepatic stellate cells (HSCs) and fewmyofibroblasts (MFs) in and around the necrotic areas expressed α1 (Ⅰ), α1 (Ⅲ) and α1 (Ⅳ)procollagen mRNA signals detected by in situhybridization at the early stage of theexperiment. All the three procollagen mRNAsignals thereafter mainly localized in fibroblasts (Fbs) and MFs in fibrotic septa during the middle and late stages of fibrosis, which distributedparallel to the corresponding collagens detected by immunohistochemical study. ln addition, the endothelial cells of sinusoids and the small blood vessels within the septa also showed α1(Ⅳ) procollagen mRNA and type Ⅳ collagen expressionCONCLUSION It is considered that 'HSC-MF-Fb' effect cell system is the major cellularsource of collagen production in liver fibrosis, in which HSCs are collagen producing precursor cells in the early liver fibrogenesis, thereafter the synthesis of type Ⅰ, Ⅲ and Ⅳ collagens (Col Ⅰ, Col Ⅲ and Col Ⅳ) mainly derives fromMFs and Fbs, which play a very important role in the progress of liver fibrosis. The endothelialcells along sinusoids, as another source of Col Ⅳ production, might participate in the capillization of liver sinusoids.DU Wei-Dong ZHANG Yue-E ZHAl Wei-Rong and ZHOU Xiao-Mei(Department of Pathology, Shanghai Medical University, Shanghai200032, China)(National Laboratory for Oncogenes and Related Genes, ShanghaiCencer Institute)See invited commentary on page 388 1999World Journal of Gastroenterology1999,5,5:47
11Interannual and Decadal Variations of Snow Cover overQinghai-Xizang Plateau and Their Relationships to Summer Monsoon Rainfall in China显示文摘Interannual and decadal variations of winter snow cover over the Qinghai-Xizang Plateau (QXP) are analyzed by using monthly mean snow depth data set of 60 stations over QXP for the period of 1958 through 1992. It is found that the winter snow cover over QXP bears a pronounced quasi-biennial oscillation. and it underwent an obvious decadal transition from a poor snow cover period to a rich snow cover period in the late 1970’s during the last 40 years. It is shown that the summer rainfall in the eastern China is closely associated with the winter snow cover over QXP not only in the interannual variation but also in the decadal variation. A clear relationship exists in the quasi-biennial oscillation between the summer rainfall in the northern part of North China and the southern China and the winter snow cover over QXP. Furthermore, the summer rainfall in the four climate divisions of Qinling-Daba Mountains, the Yangtze-Huaihe River Plain, the upper and lower reaches of the Yangtze River showed a remarkable transition from drought period to rainy period in the end of 1970’s, in good correspondence with the decadal transition of the winter snow cover over QXP.陈烈庭 吴仁广 2000Advances in Atmospheric Sciences2000,17,1:50
12Why are social network transactions important? Evidence based on the concentration of key suppliers and customers in China显示文摘Based on a new institutional economy framework,this study examines the formation and economic consequences of social networks(guanxi)from the perspective of key suppliers and customers in China.Results show that commercial activities which depend on networks are determined by the institutional environment.For example,companies that have lower accumulated social capital(less trust among people)and are subject to more government invention depend more on social network transactions than on the market.In addition,this study shows that network transactions can provide benefits to firms,especially in weak institutional environments.Networks can reduce transaction costs by reducing information asymmetry,i.e.,increased network dependence is associated with lower credit costs and lower advertising and sales costs.Networks can also reduce the effect of industry shocks,especially negative shocks,by creating a bonding mechanism.This study contributes to our understanding of social networks in emerging markets by providing evidence on network transactions with key suppliers and customers and their influence on firms'accounting behavior.Xiang Kong 2011China Journal of Accounting Research2011,,3:46
13Solid-state fermentation of corn-soybean meal mixed feed with Bacillus subtilis and Enterococcus faecium for degrading antinutritional factors and enhancing nutritional value显示文摘Background: Corn and soybean meal(SBM) are two of the most common feed ingredients used in pig feeds.However, a variety of antinutritional factors(ANFs) present in corn and SBM can interfere with the bioavailability of nutrients and have negative health effects on the pigs. In the present study, two-stage fermentation using Bacillus subtilis followed by Enterococcus faecium was carried out to degrade ANFs and improve the nutritional quality of corn and SBM mixed feed. Furthermore, the microbial composition and in vitro nutrient digestibility of inoculated mixed feed were determined and compared those of the uninoculated controls.Results: During the fermentation process, B. subtilis and lactic acid bacteria(LAB) were the main dominant bacteria in the solid-state fermented inoculated feed, and fermentation produced a large amount of lactic acid(170 mmo L/kg),which resulted in a lower pH(5.0 vs. 6.4) than the fermented uninoculated feed. The amounts of soybean antigenic proteins(β-conglycinin and glycinin) in mixed feed were significantly decreased after first-stage fermentation with B. subtilis. Inoculated mixed feed following two-stage fermentation contained greater concentratioin of crude protein(CP), ash and total phosphorus(P) compared to uninoculated feed, whereas the concentrations of neutral detergent fiber(NDF), hemicellulose and phytate P in fermendted inoculated feed declined(P < 0.05) by 38%, 53%, and 46%,respectively. Notably, the content of trichloroacetic acid soluble protein(TCA-SP), particularly that of small peptides and free amino acids(AA), increased 6.5 fold following two-stage fermentation. There was no difference in the total AA content between fermented inoculated and uninoculated feed. However, aromatic AAs(Phe and Tyr) and Lys in inoculated feed increased, and some polar AAs, including Arg, Asp, and Glu, decreased compared with the uninoculated feed. In vitro dry matter and CP digestibility of inoculated feed improved(P < 0.05) compared with the uninoculated feed.Conclusions: Our results suggest that two-stage fermentation using B. subtilis followed by E. faecium is an effective approach to improve the quality of corn-soybean meal mixed feed.Changyou Shi Yu Zhang Zeqing Lu Yizhen Wang 2017Journal of Animal Science and Biotechnology2017,8,4:44
14Characteristics of gastric cancer in Asia显示文摘Gastric cancer(GC)is the fourth most common cancer in the world with more than 70%of cases occur in the developing world.More than 50%of cases occur in Eastern Asia.GC is the second leading cause of cancer death in both sexes worldwide.In Asia,GC is the third most common cancer after breast and lung and is the second most common cause of cancer death after lung cancer.Although the incidence and mortality rates are slowly declining in many countries of Asia,GC still remains a significant public health problem.The incidence and mortality varies according to the geographic area in Asia.These variations are closely related to the prevalence of GC risk factors;especially Helicobacter pylori(H.pylori)and its molecular virulent characteristics.The gradual and consistent improvements in socioeconomic conditions in Asia have lowered the H.pylori seroprevalence rates leading to a reduction in the GC incidence.However,GC remains a significant public health and an economic burden in Asia.There has been no recent systemic review of GC incidence,mortality,and H.pylori molecular epidemiology in Asia.The aim of this report is to review the GC incidence,mortality,and linkage to H.pylori in Asia.Rubayat Rahman Akwi W Asombang Jamal A Ibdah 2014World Journal of Gastroenterology2014,20,16:50
15Ultrahigh pressure (>7 GPa) gneissic K-feldspar (-bearing) garnet clinopyroxenite in the Altyn Tagh, NW China: Evi- dence from clinopyroxene exsolution in garnet显示文摘The exsolution of clinopyroxene and rutile in coarse-grain garnet is found in the gneissic K-feldspar(-bearing) garnet clinopyroxenite from Yinggelisayi in the Altyn Tagh, NW China. The maximum content of the exsolved clinopyroxene in the garnet is up to >5% by volume. The reconstructed precursor garnet (Grt1) before exsolution has a maximum Si content of 3.061 per formula uint, being of supersilicic or majoritic garnet. The peak-stage metamorphic pressure of >7 GPa is estimated using the geobarometer for volume percentage of exsolved pyroxene in garnet and the Si-(Al+Cr) geobarometer for majoritic garnet, and the temperature of about 1000℃ using the ternary alkali-feldspar geothermometer and the experimental data of ilmen- ite-magnetite solid solution. The protoliths of the rocks are intra-plate basic and intermediate ig- neous rocks, of which the geochemical features indicate that they are probably the products of the evolution of basic magma deriving from the continental lithosphere mantle. The rocks are in outcrops associated with ultrahigh pressure garnet-bearing lherzolite and ultrahigh pressure garnet granitoid gneiss. All of these data suggest that the ultrahigh pressure metamorphic rocks in the Altyn Tagh are the products of deep-subduction of the continental crust, and such deep- subduction probably reaches to >200 km in depth. This may provide new evidence for further discussion of the dynamic mechanism of the formation and evolvement of the Altyn Tagh and the other collision orogenic belts in western China.LIU Liang1,3, CHEN Danling1, ZHANG Anda1, SUN Yong1, WANG Yan1, YANG Jiaxi1,2 & LUO Jinhai1 1. Key Laboratory of Continental Dynamics of the Ministry of Education of China, Northwest University, Xi’an 710069, China 2. College of Earth Science and Land Resources, Chang’an University, Xi’an 710054, China 3. The Laboratory of Orogen and Basin of the Ministry of Education, Peking University, Beijing 100871, China 2005Science China Earth Sciences2005,48,7:38
16Eolian evidence from the Chinese Loess Plateau: the onset of the Late Cenozoic Great Glaciation in the Northern Hemisphere and Qinghai-Xizang Plateau uplift forcing显示文摘On the basis of a newly-constructed record of magnetic susceptibility (SUS) and the depositional rate change of eolian loess-red clay sequences in the last 7.2 Ma BP from the Loess Plateau, together with a comparison of a record of δ18O values from the equatorial East Pacific Ocean and eolian Quartz flux variations from the North Pacific Ocean, the evolutionary process of the Late Cenozoic Great Glaciation in the Northern Hemisphere can be divided into three stages: the arrival stage around 7.2—3.4 Ma BP, the initial stage at about 3.4—2.6 Ma BP, and the Great Ice Age since 2.6 Ma BP. The evolution of the East Asian monsoon is characterized by paired winter and summer monsoons, and it is basically composed of the initial stage of weak winter and summer monsoons, the transitional stage of simuhaneous increase in intensity of winter and summer monsoons, and the prevailing stage of strong winter and weak summer monsoons, or weak winter and strong summer monsoons. The Late Cenozoic global tectonic安芷生 王苏民 吴锡浩 陈明扬 孙东怀 刘秀铭 王富葆 李力 孙有斌 周卫健 周杰 刘晓东 鹿化煜 张云翔 董光荣 强小科 1999Science China Earth Sciences1999,42,3:39
17IMPACTS OF CLIMATE CHANGE ON CROPPING SYSTEM AND ITS IMPLICATION FOR AGRICULTURE IN CHINA显示文摘Based on the analyses on amplitudes of historical variation of temperature and precipitation inthe past 500 years and latest 100 years,according to the regional climate change scenarios forChina estimated by composite GCM,the potential impacts of climate change on cropping systemsin China in future are simulated and assessed using the cropping system model developmentspecially for the Chinese cropping patterns.It is shown that under the projected future climatechange by 2050 the most parts of the present double cropping area would be replaced by thedifferent triple cropping patterns while the current double cropping area would shift towards thecentral part of the present single cropping area.More explicitly,the northern boundary of triplecropping area would shift from its current border at the Changjing River to the Huanghe River,ashift of more than 5 degrees of latitude.And the shift of multiple cropping areas leads to asignificant decrease of single cropping area.Furthermore,considering the changes mentioned above in combination with the likely negativebalance of precipitation and evapotranspiration and,therefore,increase of moisture stress(i.e.less water availability),as well as the possible increase of heat stress disaster and decrease of LGS(length of growing season),the potential implication of climate change for agriculture in China arealso analyzed roughly in this paper.As a result,however,it is still very difficult to reach a specific conclusion that the futureclimate change will he favorable or unfavorable to farm in China because of the complicated Chinesefarming patterns,the complex-various social and economic environment of agriculturaldevelopment and,especially,a great scientific uncertainties in the investigation/prediction ofclimate change.王馥棠 1997Acta meteorologica Sinica1997,11,4:37
18Endoscopic and surgical resection of T1a/T1b esophageal neoplasms: A systematic review显示文摘AIM: To investigate potential therapeutic recommendations for endoscopic and surgical resection of T1a/ T1b esophageal neoplasms. METHODS: A thorough search of electronic databases MEDLINE, Embase, Pubmed and Cochrane Library, from 1997 up to January 2011 was performed. An analysis was carried out, pooling the effects of outcomes of 4241 patients enrolled in 80 retrospective studies. For comparisons across studies, each reporting on only one endoscopic method, we used a random effects meta-regression of the log-odds of the outcome of treatment in each study. 'Neural networks' as a data mining technique was employed in order to establish a prediction model of lymph node status in superficial submucosal esophageal carcinoma. Another data mining technique, the 'feature selection and root cause analysis', was used to identify the most impor-tant predictors of local recurrence and metachronous cancer development in endoscopically resected patients, and lymph node positivity in squamous carcinoma (SCC) and adenocarcinoma (ADC) separately in surgically resected patients. RESULTS: Endoscopically resected patients: Low grade dysplasia was observed in 4% of patients, high grade dysplasia in 14.6%, carcinoma in situ in 19%, mucosal cancer in 54%, and submucosal cancer in 16% of patients. There were no significant differences between endoscopic mucosal resection and endoscopic submucosal dissection (ESD) for the following parameters: complications, patients submitted to surgery, positive margins, lymph node positivity, local recurrence and metachronous cancer. With regard to piecemeal resection, ESD performed better since the number of cases was significantly less [coefficient: -7.709438, 95%CI: (-11.03803, -4.380844), P < 0.001]; hence local recurrence rates were significantly lower [coefficient: -4.033528, 95%CI: (-6.151498, -1.915559),P < 0.01]. A higher rate of esophageal stenosis was observed following ESD [coefficient: 7.322266, 95%CI: (3.810146, 10.83439), P < 0.001]. A significantly greater number of SCC patients were submitted to surgery (log-odds, ADC: -2.1206 ± 0.6249 vs SCC: 4.1356 ± 0.4038, P < 0.05). The odds for re-classification of tumor stage after endoscopic resection were 53% and 39% for ADC and SCC, respectively. Local tumor recurrence was best predicted by grade 3 differentiation and piecemeal resection, metachronous cancer development by the carcinoma in situ component, and lymph node positivity by lymphovascular invasion. With regard to surgically resected patients: Significant differences in patients with positive lymph nodes were observed between ADC and SCC [coefficient: 1.889569, 95%CI: (0.3945146, 3.384624), P<0.01). In contrast, lymphovascular and microvascular invasion and grade 3 patients between histologic types were comparable, the respective rank order of the predictors of lymph node positivity was: Grade 3, lymphovascular invasion (L+), microvascular invasion (V+), submucosal (Sm) 3 invasion, Sm2 invasion and Sm1 invasion. Histologic type (ADC/SCC) was not included in the model. The best predictors for SCC lymph node positivity were Sm3 invasion and (V+). For ADC, the most important predictor was (L+). CONCLUSION: Local tumor recurrence is predicted by grade 3, metachronous cancer by the carcinoma insitu component, and lymph node positivity by L+. T1b cancer should be treated with surgical resection.George Sgourakis Ines Gockel Hauke Lang 2013World Journal of Gastroenterology2013,19,9:40
19甜杨抗冻转录因子ICE1基因的in silico克隆及其分析显示文摘ICE1基因编码类似MYC的bHLH转录因子,可特异地结合到CBF3启动子的MYC作用元件并诱导CBF/DREB1下游基因的转录表达。本文采用电子克隆的方法,以拟南芥ICE1蛋白序列为信息探针,利用杨树EST数据库和毛果杨基因组序列拼接的结果,设计引物并通过RT-PCR从甜杨克隆了杨树的第一个ICE1基因。其cDNA长1706bp,含有完整的开放阅读框,可编码543个氨基酸的MYC类蛋白。编码蛋白序列含有bHLH区,核定位信号(NLS)区,富S区和转膜区各1个。Blast分析表明,cDNA序列及其推导的氨基酸序列均与拟南芥和芥菜的ICE1存在着较高的同源性,说明所获得的cDNA可能是甜杨ICE1基因(PsICE1,DQ481236)。通过网络服务器平台进行PsICE1的功能预测,结果显示PsICE1含有bHLH保守功能域,具有多个磷酸化位点和跨膜区域。另外,ICE1的电子表达谱分析结果发现,ICE1几乎可在植物中整株表达,在多种组织和不同发育过程均表达,这也在一定程度上说明了ICE1是组成型表达,以及ICE1可能在植物的生长发育中也起着重要作用。林元震 张志毅 刘纯鑫 郭海 朱保庆 陈晓阳 2007分子植物育种2007,5,3:38
20利用3种,in vitro方法比较研究污染土壤中铅、砷生物可给性显示文摘采用PBET(Physiologically Based Extraction Test)、SBET(Simple Bioavailability Extraction Test)和IVG(In Vitro Gastrointestinal)3种in vitro方法研究采自浙江上虞的4种污染土壤中铅、砷的生物可给性。结果表明,3种方法得到的铅、砷在模拟胃肠液中的溶解度不同,胃阶段,采用SBET方法得到的数值最大,放有食物的IVG方法得到的数值最小;小肠阶段,不添加食物的IVG方法得到的数值最大,放有食物的IVG方法得到的数值最小。3种方法得到的铅、砷在模拟胃肠液中的生物可给性不同,胃阶段,采用SBET方法得到的数值最大,4种土壤中铅的生物可给性分别为89.2%、71.3%,56.2%和43.7%,砷的生物可给性分别为7.4%、6.6%,5.9%和7.4%。放有食物的IVG方法得到的数值最小,4种土壤中铅的生物可给性分别为30.1%、26.9%、18.4%和15.0%,砷的生物可给性分别为3.8%、4.9%、2.8%和3.4%。小肠阶段,不添加食物的IVG方法得到的数值最大,4种土壤中铅的生物可给性分别为13.9%、11.1%、21.8%和7.7%,砷的生物可给性分别为7.1%、7.3%、4.6%和7.3%。放有食物的IVG方法得到的数值最小,4种土壤中铅的生物可给性分别为3.4%、1.7%、4.3%和1.9%,砷的生物可给性分别为3.3%、4.8%、2.8%和2.8%。3种方法使用的条件不同如胃肠溶液成分及其pH是3种方法之间得出的结果差异的主要原因,4种土壤之间的差异则主要是土壤属性差异等原因造成的。崔岩山 陈晓晨 朱永官 2008农业环境科学学报2008,27,2:37
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