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TATA-box binding protein-associated factor 2 regulates grain size in rice
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作者 Ling Jiang Ning Jiang +6 位作者 Zejun Hu xuejun sun Xian Xiang Yahui Liu Mingwei Wu Chunming Liu Xiaojin Luo 《The Crop Journal》 SCIE CSCD 2023年第2期438-446,共9页
Grain size,characterized by a combination of grain length,width,and thickness,is one of the major determinants of yield in rice.The present study identified TATA-box binding protein-associated factor 2(TAF2)as an esse... Grain size,characterized by a combination of grain length,width,and thickness,is one of the major determinants of yield in rice.The present study identified TATA-box binding protein-associated factor 2(TAF2)as an essential component regulating transcription and determining grain size in rice.Map-based cloning showed that a G/T substitution in TAF2 resulted in a naturally occurring mutant called reduced grain size and plant height 1(rgh1).The mutants,with weak edited rgh1 alleles,exhibited a small grain phenotype with reduced grain length and width,while the severe knockout mutant(rgh1-2s)was dwarf and completely sterile.Allelic test performed between rgh1 and several edited alleles confirmed that the mutation in TAF2 caused the rgh1 phenotype.GUS staining showed that TAF2 was mainly expressed in the vascular bundles of roots,stems,leaves,and grains.The cytological analysis revealed that reduced cell division in the glumes resulted in the small grain phenotype of rgh1.Further RNA-sequencing detected altered expression of genes involved in the basic biological processes in rgh1 mutant.These findings provide novel insights into the TAF2-mediated genetic mechanism regulating grain size in rice. 展开更多
关键词 Grain size TAF2 RGH1 Cell division RICE
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Bioinformatic analysis and in vivo validation of angiogenesis related genes in inflammatory bowel disease
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作者 ZEPENG DONG CHENYE ZHAO +4 位作者 SHIBO HU KUI YANG JUNHUI YU xuejun sun JIANBAO ZHENG 《BIOCELL》 SCIE 2023年第12期2735-2745,共11页
Angiogenesis plays a significant role in the occurrence and development of inflammatory bowel disease(IBD).The aim of this study is to explore potential angiogenesis related genes(ARGs)in IBD through bioinformatics an... Angiogenesis plays a significant role in the occurrence and development of inflammatory bowel disease(IBD).The aim of this study is to explore potential angiogenesis related genes(ARGs)in IBD through bioinformatics analysis and in vivo experiments.Methods:GSE57945,GSE87466,and GSE36807 were obtained from the Gene Expression Omnibus database.GSE57945 was used as the training set,while GSE87466 and GSE36807 were used as the validation set.The key ARGs associated with IBD were identified using the least absolute shrinkage and selection operator(LASSO)and random forest methods.These identified ARGs were then utilized to construct a diagnostic model for IBD.The Single-Sample Genome Enrichment Analysis,Cibersort,and Xcell methods were used to evaluate the immune infiltration.Expression of amyloid beta precursor protein(APP)was verified in the IBD mouse model induced by dextran sulfate sodium using immunohistochemistry(IHC).Results:The receiver operating curve area of GSE57945 was 0.948.Two distinct clusters were identified using consensus clustering and non-negative matrix factorization clustering.Subsequent analyses revealed significant differences in immune levels and functional enrichment between the two clusters.The successful construction of the animal model for the IBD was evident by hematoxylin and eosin staining,while IHC results showed a high expression of APP in IBD and a low expression in normal tissues.Conclusion:Our findings provide new insights into the diagnosis of IBD by ARGs,and APP could be a potential novel biomarker for IBD and promising therapeutic targets. 展开更多
关键词 Inflammatory bowel disease Angiogenesis related genes BIOINFORMATICS Immune microenvironment Diagnostic model
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Recent Advances in Finite Element Applications in Artificial Lumbar Disc Replacement 被引量:2
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作者 Zhenjun Zhang Yitao sun +3 位作者 xuejun sun Yang Li Zhenhua Liao Weiqiang Liu 《Journal of Biomedical Science and Engineering》 2016年第10期1-8,共9页
As a new choice for the treatment of degenerative lumbar disease, artificial lumbar disc replacement has been widely used in clinical surgery. The finite element is a very effective method to predict and simulate the ... As a new choice for the treatment of degenerative lumbar disease, artificial lumbar disc replacement has been widely used in clinical surgery. The finite element is a very effective method to predict and simulate the surgery effect. The purpose of this paper is to review the applications of finite element in artificial lumbar disc replacement, such as design of artificial lumbar disc prosthesis, risk and effect evaluation of artificial lumbar disc replacement, and assessment of operation methods. Lastly, we discuss the future development of finite element method applied in this field, including personalized design of the prosthesis, postoperative behavior guide, and artificial lumbar disc replacement combined with fusion surgery. In conclusion, as an invaluable complement to biomechanical experiments and clinical studies, the finite element method makes important contributions to our understanding of biomechanics of intervertebral disc, and plays an important role in the field of artificial lumbar disc replacement. 展开更多
关键词 Finite Element Artificial Lumbar Disc Artificial Lumbar Disc Prosthesis Artificial Lumbar Disc Replacement
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Hydrogen-rich saline protects against ultraviolet B radiation injury in rats 被引量:6
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作者 Ze Guo Bingrong Zhou +2 位作者 Wei Li xuejun sun Dan Luo 《The Journal of Biomedical Research》 CAS 2012年第5期365-371,共7页
Exposure of skin to solar ultraviolet(UV) radiation induces photo-damage.Ultraviolet B(UVB) is the major component of UV radiation which induces the production of reactive oxygen species(ROS) and plays an impor-tant r... Exposure of skin to solar ultraviolet(UV) radiation induces photo-damage.Ultraviolet B(UVB) is the major component of UV radiation which induces the production of reactive oxygen species(ROS) and plays an impor-tant role in photo-damage.Hydrogen gas reduces ROS and alleviates inflammation.In this study,we sought to demonstrate that hydrogen-rich saline has the effect on skin injuries caused by UVB radiation.UVB radiation was irradiated on female C57BL/6 rats to induce skin injury.Hydrogen-rich saline and nitrogen-rich saline were ad-ministered to rats by intraperitoneal injection.Skin damage was detected by microscope after injury.UVB radia-tion had a significant affection in tumor necrosis factor alpha,interleukin(IL)-1β and IL-6 levels,tissue superox-ide dismutase,malondialdehyde and nitric oxide activity.Hydrogen-rich saline had a protective effect by altering the levels of these markers and relieved morphological skin injury.Hydrogen-rich saline protected against UVB radiation injury,possibly by reducing inflammation and oxidative stress. 展开更多
关键词 生理盐水 保护作用 紫外线B 辐射损伤 富氢 超氧化物歧化酶 活性氧物种 皮肤损伤
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Research progress on behaviors and environmental effects of mercury in the cryosphere of the Tibetan Plateau:a critical review 被引量:1
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作者 ShiWei sun ShiChang Kang +2 位作者 QiangGong Zhang JunMing Guo xuejun sun 《Research in Cold and Arid Regions》 CSCD 2022年第1期1-22,共22页
The behavior and fates of environmental pollutants within the cryosphere and the associated environmental impacts are of increasing concerns in the context of global warming.The Tibetan Plateau(TP),also known as the&q... The behavior and fates of environmental pollutants within the cryosphere and the associated environmental impacts are of increasing concerns in the context of global warming.The Tibetan Plateau(TP),also known as the"Third Pole",represents one of the most important cryospheric regions in the world.Mercury(Hg)is recognized as a global pollutant.Here,we summarize the current knowledge of Hg concentration levels,pools and spatio-temporal distribution in cryospheric environments(e.g.,glacier,permafrost),and its transfer and potential cycle in the TP cryospheric region.Transboundary transport of anthropogenic Hg from the surrounding heavily-polluted regions,such as South and Southeast Asia,provides significant sources of atmospheric Hg depositions onto the TP cryosphere.We concluded that the melting of the cryosphere on the TP represents an increasing source of Hg and brings a risk to the TP environment.In addition,global warming acts as an important catalyst accelerating the release of legacy Hg from the melting cryosphere,adversely impacting ecosystems and biological health.Furthermore,we emphasize on the remaining gaps and proposed issues needed to be addressed in future work,including enhancing our knowledge on some key release pathways and the related environmental effects of Hg in the cryospheric region,integrated observation and consideration of Hg distribution,migration and cycle processes at a key region,and uses of Hg isotopic technical and Hg models to improve the understanding of Hg cycling in the TP cryospheric region. 展开更多
关键词 MERCURY CRYOSPHERE environmental effects Tibetan Plateau
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Hydrogen-rich Saline Reduces Atherogenesis in Apolipoprotein E Knockout Mice Fed a High-fat Diet by Inhibiting the Non-HDL-mediated Arterial Inflammation and Promoting the Expression of Genes Involving Reverse Cholesterol Transport
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作者 Hua Tian Guohua Song +6 位作者 Shucun Qin xuejun sun Jia Liu Yang Yu Yanhong Si Shutong Yao Jiafu Wang 《中国动脉硬化杂志》 CAS CSCD 北大核心 2011年第3期277-277,共1页
Aim Hydrogen(dihydrogen,H2) is an effective antioxidant to reduce oxidative stress and oxidative stress is implicated in atherogene-sis.In this study we examined whether hydrogen-saturated saline can prevent atheroscl... Aim Hydrogen(dihydrogen,H2) is an effective antioxidant to reduce oxidative stress and oxidative stress is implicated in atherogene-sis.In this study we examined whether hydrogen-saturated saline can prevent atherosclerosis in apolipoprotein E knockout(apoE-/-) mice fed either chowdiet or high-fat diet,and characterized the underlying molecular mechanisms.Methods and Results The atherosclerotic lesion formation displayed by oil red O staining positive area was reduced significantly in either aortic root section or aortic arch en face in hydrogen administrated apoE-/-mice fed either chowdiet or high-fat diet,compared to the control.Plasma analysis by enzymatic method showed that total cholesterol(TC) and non-high-density lipoprotein cholesterol(non-HDL-C)were remarkably decreased by treatment with hydrogen.Western blot analysis revealed a significant decrease of both plasma apoli-poprotein B(apoB) level and hepatic expression of apoB after hydrogen treatment,suggesting hydrogen could downregulate the expression of the major protein constituent of non-HDL.In addition,spectrophotometric measurement showed that plasma levels of malondi-aldehyde(MDA) and serum amyloid Awas decreased and paraoxonase-1 activity was increased in mice treated with hydrogen,suggesting plasma lipid oxidation and peroxidation was impaired by hydrogen treatment.Besides,the MDA content of the non-HDL,whichseparated by ultracentrifugation from the plasma of mice treated with and without hydrogen,was reduced by hydrogen,suggesting the oxidation of non-HDL was impaired by hydrogen.Moreover,we found hydrogen treatment significantly suppressed the production of tumor necrosis factor-α(TNF-α) and interleukin-6 in RAW264.7 macrophages after stimulation with the isolated non-HDL,suggesting hydrogen reduces atherogenesis by inhibiting non-high-density lipoprotein(HDL)-mediated inflammation.Furthermore,immunohis-tochemistry of aortic valve sections revealed that hydrogen attenuated lesion formation by suppressing the expression of several proin-flammatory factors and decreasing vessel wall infiltration of macrophages,indicating hydrogen-treatment reduces arterial inflammation.Besides,real-time PCR and western blot analysis disclosed that the expression of several transporter genes involved in the process ofreverse cholesterol transport,including hepatic scavenger receptor class B type I(SR-BI),ATP-binding cassette(ABC) transporters ABCG8,ABCB4,ABCB11,and macrophage SR-BI,were all induced by hydrogen treatment.Conclusion These results re-vealed that administration of hydrogen-rich saline reduces atherogenesis in apoE-/-mice fed a high-fat diet by inhibiting the non-HDL-mediated arterial inflammation and promoting the expression of genes involving reverse cholesterol transport. 展开更多
关键词 抗氧化剂 蛋白胆固醇 临床分析 医学研究
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Post-transcriptional regulation of grain weight and shape by the RBP-A-J-K complex in rice
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作者 Ding Ren Hui Liu +10 位作者 xuejun sun Fan Zhang Ling Jiang Ying Wang Ning Jiang Peiwen Yan Jinhao Cui Jinshui Yang Zhikang Li Pingli Lu Xiaojin Luo 《Journal of Integrative Plant Biology》 SCIE CAS CSCD 2024年第1期66-85,共20页
RNA-binding proteins(RBPs)are components of the post-transcriptional regulatory system,but their regulatory effects on complex traits remain unknown.Using an integrated strategy involving map-based cloning,functional ... RNA-binding proteins(RBPs)are components of the post-transcriptional regulatory system,but their regulatory effects on complex traits remain unknown.Using an integrated strategy involving map-based cloning,functional characterizations,and transcriptomic and population genomic analyses,we revealed that RBP-K(LOC_Os08g23120),RBP-A(LOC_Os11g41890),and RBP-J(LOC_Os10g33230)encode proteins that form an RBP-A-J-K complex that negatively regulates rice yield-related traits.Examinations of the RBP-A-J-K complex indicated RBP-K functions as a relatively non-specific RBP chaperone that enables RBP-A and RBP-J to function normally.Additionally,RBP-J most likely affects GA pathways,resulting in considerable increases in grain and panicle lengths,but decreases in grain width and thickness.In contrast,RBP-A negatively regulates the expression of genes most likely involved in auxin-regulated pathways controlling cell wall elongation and carbohydrate transport,with substantial effects on the rice grain filling process as well as grain length and weight.Evolutionarily,RBP-K is relatively ancient and highly conserved,whereas RBP-J and RBP-A are more diverse.Thus,the RBP-A-J-K complex may represent a typical functional model for many RBPs and protein complexes that function at transcriptional and post-transcriptional levels in plants and animals for increased functional consistency,efficiency,and versatility,as well as increased evolutionary potential.Our results clearly demonstrate the importance of RBP-mediated post-transcriptional regulation for the diversity of complex traits.Furthermore,rice grain yield and quality may be enhanced by introducing various complete or partial loss-of-function mutations to specific RBP genes using clustered regularly interspaced palindromic repeats(CRISPR)/CRISPR-associated protein 9 technology and by exploiting desirable natural tri-genic allelic combinations at the loci encoding the components of the RBP-A-J-K complex through marker-assisted selection. 展开更多
关键词 GL11 grain weight and shape post-transcriptional regulation RNA-binding proteins
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磁压榨吻合技术治疗结直肠吻合及重建中的应用分析
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作者 李晶 卢桂芳 +8 位作者 张苗苗 刘仕琪 严小鹏 马锋 任晓阳 孙学军 吕毅 和水祥 任牡丹 《中华消化内镜杂志》 CSCD 2023年第5期397-400,共4页
回顾磁压榨吻合技术(magnetic compression anastomosis,MCA)治疗不同原因、不同类型肠道狭窄/闭锁实现肠道再通的案例,对MCA在结直肠吻合及重建中的临床应用进行分析探讨。4例患者2019年5月—2022年8月在西安交通大学第一附属医院及西... 回顾磁压榨吻合技术(magnetic compression anastomosis,MCA)治疗不同原因、不同类型肠道狭窄/闭锁实现肠道再通的案例,对MCA在结直肠吻合及重建中的临床应用进行分析探讨。4例患者2019年5月—2022年8月在西安交通大学第一附属医院及西北妇女儿童医院行结直肠MCA再通治疗。患者手术过程均顺利,实现肠道吻合再通,磁环排出时间为7~15 d,术后复查肠镜或造影提示吻合口完好。MCA可用于治疗不同原因、不同类型的结直肠狭窄及闭锁,也可用于辅助结直肠手术肠吻合。 展开更多
关键词 结肠 直肠 重建 磁压榨吻合技术 吻合
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中国经自然腔道取标本手术41841例开展现状分析:2022年医师调查报告 被引量:3
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作者 关旭 焦帅 +18 位作者 彭健 姚宏亮 王贵玉 何庆泗 郑阳春 胡军红 李太原 康亮 王振宁 蔡建春 江波 熊治国 马丹 孙学军 丁克峰 汪泳 周海涛 傅传刚 王锡山 《中华结直肠疾病电子杂志》 2023年第1期42-49,共8页
目的了解我国经自然腔道取标本手术(NOSES)开展现状,为NOSES发展提供重要参考依据。方法基于微信问卷形式,针对我国从事普通外科、肿瘤外科、妇科等专业的医师展开调查。调查内容包括医师基本信息、我国NOSES开展情况、NOSES技术培训与... 目的了解我国经自然腔道取标本手术(NOSES)开展现状,为NOSES发展提供重要参考依据。方法基于微信问卷形式,针对我国从事普通外科、肿瘤外科、妇科等专业的医师展开调查。调查内容包括医师基本信息、我国NOSES开展情况、NOSES技术培训与科研现状。结果本研究覆盖我国30个省份及地区,共收集1292份有效问卷调查表,其中开展NOSES医生为833人,占64.5%,未开展NOSES医生为459人,占35.5%。我国开展NOSES的医院共559家,开展NOSES总例数为41841例,其中结直肠肿瘤NOSES为35007例,胃肿瘤NOSES为4381例,其他疾病NOSES为2453例。根据不同取标本途径分类,经肛门取标本NOSES共33728例,经阴道取标本NOSES为7676例,经口取标本NOSES为437例。我国开展NOSES课题研究的医师占24.4%;发表NOSES论文的医师占20.2%。关于我国NOSES数据库情况,71.7%的医师未将NOSES数据上传至中国NOSES数据库。对于未来NOSES发展,91.3%的医师建议加强技术规范化培训,72.1%的医师建议向基层医生推广。结论NOSES已在我国全面普及,地域分布广泛。为进一步推进NOSES临床应用,面向基层的规范化培训是医生的迫切需求,也是NOSES未来重要发展方向。 展开更多
关键词 经自然腔道取标本手术(NOSES) 微创手术 问卷调查 现状分析
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磁力疏通技术在术后消化道狭窄中的应用 被引量:2
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作者 李宇 苏茂生 +5 位作者 孙学军 于良 刘昌 和水祥 吴荣谦 孙昊 《科学通报》 EI CAS CSCD 北大核心 2020年第13期1283-1294,共12页
磁吻合或磁力疏通技术是一种创新性的吻合技术,可完成狭窄消化道的重建.我们采用该技术治疗常规治疗方法无效的消化道狭窄,现探讨该技术的安全性及有效性.收集2012年1月~2019年10月西安交通大学第一附属医院及中国人民解放军总医院肝胆... 磁吻合或磁力疏通技术是一种创新性的吻合技术,可完成狭窄消化道的重建.我们采用该技术治疗常规治疗方法无效的消化道狭窄,现探讨该技术的安全性及有效性.收集2012年1月~2019年10月西安交通大学第一附属医院及中国人民解放军总医院肝胆外科收治的17例术后消化道狭窄患者:年龄11~78岁,男女比例11:6;胆道狭窄14例,结直肠吻合口狭窄1例,食管吻合口狭窄2例;完全性狭窄14例,顽固性狭窄3例;末次手术后0~120月发现狭窄,在接受2~8次无效的标准治疗后行磁力疏通技术治疗.疏通装置由子母稀土钕铁硼磁铁构成,柱状或环状.通过不同的输送路径,在狭窄消化道的上下端分别置入子母磁体,通过磁体间的磁力压迫狭窄组织而达到再通,再通后在新吻合口放置支架或进行扩张等治疗.观察指标包括术前狭窄距离、磁吻合再通时间、手术30 d内相关并发症、支架留置时间、吻合口狭窄复发等.采用门诊及电话随访,随访时间至2019年12月. 16例患者完成磁力疏通治疗(成功率94.1%),分别为10例胆道-胆道吻合、3例胆道-肠道吻合、1例食管-食管吻合、1例食管-胃吻合、1例结肠-直肠吻合. 3例患者术后早期子母磁环脱开, 2例自动复位, 1例再次经PTCD(percutaneous transhepatic cholangial drainage)窦道置入一枚子磁体复位耦合. 3例有手术并发症(急性胆管炎、胆道出血及结肠瘘各1例),均予保守治疗后好转. 16例术前狭窄段长度2~7.1(4±1.9) mm,再通时间7~50(15.5±10.6) d.再通后4例置入胆道塑料支架, 5例置入胆道全覆膜金属支架, 4例置入经皮肝胆道引流导管, 2例吻合口球囊扩张+金属支架置入, 1例单纯吻合口球囊扩张.再通后1~17(6.9±4.0)月, 14例患者拔出支架, 1例仍在支架治疗中.脱支架后随访3~70(22.5±24.9)月, 13例胆道狭窄者未见狭窄复发,其中2例出现胆道结石,内镜治愈;3例胃肠道狭窄者中有2例复发.综上所述,磁力疏通技术治疗复杂术后消化道狭窄微创、安全、有效,可作为常规方法治疗无效后的补救措施. 展开更多
关键词 磁吻合 胆道狭窄 食管狭窄 胃肠吻合口狭窄 结直肠吻合口狭窄 再通
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中国结直肠肿瘤经自然腔道取标本手术患者短期疗效与肿瘤学预后分析:一项5055例患者的数据库研究 被引量:14
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作者 关旭 胡茜玥 +46 位作者 姜争 韦烨 孙东辉 吴淼 周海涛 姚宏亮 宋军民 王贵玉 胡军红 任明扬 徐庆 蔡建春 彭健 马丹 郑阳春 何庆泗 江波 王泽军 李太原 燕速 陈路川 李铁钢 熊治国 池畔 康亮 于刚 邓小东 张宏 谢铭 韦建宝 宫红彦 孙学军 臧卫东 宋永茂 赫鹏 文政琦 张春旭 王昱晟 陈瑛罡 谢光伟 李明章 俞少俊 刘海鹰 蒲敏 傅传刚 王锡山 中国经自然腔道取标本手术联盟 《Science Bulletin》 SCIE EI CSCD 2022年第13期1331-1334,M0003,共5页
经自然腔道取标本手术(NOSES)通过无切口理念与常规手术器械的结合,表现出极佳的微创效果,并带给患者全新的就医感受.目前,尽管NOSES已广泛用于结直肠肿瘤治疗,大量研究也表明相比常规腹腔镜手术,NOSES具有恢复快、创伤小、疼痛轻等优势... 经自然腔道取标本手术(NOSES)通过无切口理念与常规手术器械的结合,表现出极佳的微创效果,并带给患者全新的就医感受.目前,尽管NOSES已广泛用于结直肠肿瘤治疗,大量研究也表明相比常规腹腔镜手术,NOSES具有恢复快、创伤小、疼痛轻等优势,但绝大多数研究均为小样本、单中心回顾性研究.本研究旨在通过分析我国5055例结直肠肿瘤NOSES患者数据,进一步探讨NOSES的短期疗效与预后.研究对象中,经直肠NOSES占整体比例的90.3%,经阴道NOSES占9.7%.NOSES术后短期并发症发生率为14.1%,吻合口瘘发生率为4.9%,腹盆腔感染率为1.9%.患者3年总生存率为93.2%,无病生存率为82.2%,局部复发率为3.6%.研究结果提示NOSES具有较好的安全性与可行性,为其应用于结直肠肿瘤治疗提供了证据. 展开更多
关键词 结直肠肿瘤 肿瘤学 并发症发生率 无病生存率 吻合口瘘 回顾性研究 总生存率 经直肠
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Insights into mercury in glacier snow and its incorporation into meltwater runoff based on observations in the southern Tibetan Plateau 被引量:9
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作者 Shiwei sun Shichang Kang +4 位作者 Junming Guo Qianggong Zhang Rukumesh Paudyal xuejun sun Dahe Qin 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2018年第6期130-142,共13页
The Tibetan Plateau(TP) is recognized as "Water Tower of Asia". Yet our understanding of mechanisms influencing incorporation of mercury(Hg) into freshwater in mountain glaciers on the TP remains quite limit... The Tibetan Plateau(TP) is recognized as "Water Tower of Asia". Yet our understanding of mechanisms influencing incorporation of mercury(Hg) into freshwater in mountain glaciers on the TP remains quite limited. Extensive sampling of environmental matrices(e.g., snow/ice)were conducted on the East Rongbuk glacier on Mt. Everest and Zhadang glacier on Mt.Nyainqentanglha for Hg speciation analysis. Speciated Hg behaved quite different during snowmelt: a preferential early release of DHg(dissolved Hg) was observed at the onset of snowmelt, whereas PHg(particulate-bound Hg) and THg(total Hg) become relatively enriched in snow and released later. Small fraction of Hg in snow was lost during a snowmelt day(18.9%–34.7%) with a large proportion(58.1%–87.3%) contributed by PHg decrease, indicating that the deposited Hg is most likely retained in glacier snow/ice. Furthermore, THg were positively correlated with PHg and crustal major ions(e.g., Ca^(2+), Mg^(2+)) during snowmelt, indicating that Hg is mainly migrated with particulates. The main pathway of Hg loss during snowmelt was most probably associated with release of PHg with meltwater, which was greatly influenced by ablation intensity of snow/ice. This should be paid particular concern as Hg preserved in mountain glaciers will mostly enter aquatic ecosystem as climate warms, impacting on downstream ecosystems adversely. Obvious decrease of THg during the downstream transport from glacier was observed with a large proportion contributed by PHg decrease. The main removal mechanism of Hg was associated with sedimentation of PHg during the transport process. 展开更多
关键词 冰河 水塔 高原 西藏 银基 流量 DHg 生态系统
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Trace elements and rare earth elements in wet deposition of Lijiang,Mt.Yulong region,southeastern edge of the Tibetan Plateau 被引量:3
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作者 Junming Guo Shichang Kang +6 位作者 Jie Huang Mika Sillanpaa Hewen Niu xuejun sun Yuanqing He Shijing Wang Lekhendra Tripathee 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2017年第2期18-28,共11页
In order to investigate the compositions and wet deposition fluxes of trace elements and rare earth elements(REEs) in the precipitation of the southeastern edge of the Tibetan Plateau, 38 precipitation samples were co... In order to investigate the compositions and wet deposition fluxes of trace elements and rare earth elements(REEs) in the precipitation of the southeastern edge of the Tibetan Plateau, 38 precipitation samples were collected from March to August in 2012 in an urban site of Lijiang city in the Mt. Yulong region. The concentrations of most trace elements and REEs were higher during the non-monsoon season than during the monsoon season,indicating that the lower concentrations of trace elements and REEs observed during monsoon had been influenced by the dilution effect of increased precipitation. The concentrations of trace elements in the precipitation of Lijiang city were slightly higher than those observed in remote sites of the Tibetan Plateau but much lower than those observed in the metropolises of China, indicating that the atmospheric environment of Lijiang city was less influenced by anthropogenic emissions, and, as a consequence, the air quality was still relatively good. However, the results of enrichment factor and principal component analysis revealed that some anthropogenic activities(e.g., the increasing traffic emissions from the rapid development of tourism) were most likely important contributors to trace elements, while the regional/local crustal sources rather than anthropogenic activities were the predominant contributors to the REEs in the wet deposition of Lijiang city. Our study was relevant not only for assessing the current status of the atmospheric environment in the Mt. Yulong region, but also for specific management actions to be implemented for the control of atmospheric inputs and the health of the environment for the future. 展开更多
关键词 中微量元素 湿沉降通量 稀土元素 丽江市 山地 玉龙 东南部 云南省
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Copper(I)-Catalyzed Interrupted Click/Sulfenylation Cascade:One-Pot Synthesis of Sulfur Cycle Fused 1,2,3-Triazoles
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作者 Weiguo Wang Shuai Huang +3 位作者 Shikun Yan xuejun sun Chen-Ho Tung Zhenghu Xu 《Chinese Journal of Chemistry》 SCIE CAS CSCD 2020年第5期445-448,共4页
Herein,we report a practical protocol for the synthesis of sulfur cycle fused 1,2,3-triazoles through a copper(I)-catalyzed tandem click/intramolecular sulfenylation reaction.The reaction proceeded via a copper-cataly... Herein,we report a practical protocol for the synthesis of sulfur cycle fused 1,2,3-triazoles through a copper(I)-catalyzed tandem click/intramolecular sulfenylation reaction.The reaction proceeded via a copper-catalyzed alkyne azide cycloaddition,followed by interception of the in situ formed cuprate-triazole intermediate with p-toluenesulfonothioate.This reaction shows broad substrate scope,complete regioselectivity,and excellent functional group tolerance under mild reaction conditions. 展开更多
关键词 reaction. CATALYZED COPPER
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