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2010年-2015年SEER数据库肺腺鳞癌患者临床特征及预后分析 被引量:13
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作者 詹成 江天 +2 位作者 杨晓冬 郭卫刚 谭黎杰 《中国肺癌杂志》 CAS CSCD 北大核心 2018年第8期600-609,共10页
背景与目的肺癌发病率和死亡率均位居所有恶性肿瘤的第一,严重影响人类健康。非小细胞肺癌(non-small cell lung cancer,NSCLC)中常见病理类型为腺癌和鳞癌,临床研究和关注较多,而肺腺鳞癌是一种较为罕见的肺癌病理类型,其临床特征及预... 背景与目的肺癌发病率和死亡率均位居所有恶性肿瘤的第一,严重影响人类健康。非小细胞肺癌(non-small cell lung cancer,NSCLC)中常见病理类型为腺癌和鳞癌,临床研究和关注较多,而肺腺鳞癌是一种较为罕见的肺癌病理类型,其临床特征及预后相关因素尚未完全明确。本研究即对肺腺鳞癌的临床特征及预后进行分析,并构建了列线图来预测患者的预后。方法我们纳入了2010年-2015年美国SEER(Surveillance,Epidemiology,and End Results)数据库中的肺腺鳞癌数据,与同期的肺腺癌和肺鳞癌的临床特征和预后进行了比较。随后我们采用单因素和多因素分析研究了肺腺鳞癌患者预后的独立相关因素,以此构建了列线图并进行了验证。结果我们一共入组了肺腺鳞癌患者1,453例。与同期的肺腺癌和肺鳞癌患者相比较,肺腺鳞癌患者在大多数变量中的分布情况均介于肺腺癌和鳞癌之间,其预后也优于肺鳞癌但差于肺腺癌患者。多因素分析发现,年龄、分化程度、肿瘤-淋巴结-转移(tumor-node-metastasis,TNM)、手术和化疗是患者预后的独立影响因素(P均<0.001)。我们以此构建了列线图,其C-index为0.783(0.767-0.799),区分度检验和一致性检验均表明这一列线图可以有效地预测患者预后。结论肺腺鳞癌具有独特的临床病理和预后特征。年龄、分化、T、N、M、手术和化疗状况是肺腺鳞癌患者预后的独立预测因素。我们以此构建的列线图可以较好地预测患者预后。 展开更多
关键词 肺肿瘤 腺鳞癌 列线图 SEER数据库
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Cutting edge preparation of microdrills by shear thickening polishing for improved hole quality in electronic PCBs
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作者 Jiahuan WANG Mingfeng KE +7 位作者 Jiepei LIAO Yu ZHOU Saurav GOEL Jaya VERMA Xu WANG weigang guo Julong YUAN Binghai LYU 《Frontiers of Mechanical Engineering》 SCIE CSCD 2024年第2期99-107,共9页
Printed circuit boards(PCBs)are representative composite materials,and their high-quality drilling machining remains a persistent challenge in the industry.The finishing of the cutting edge of a microdrill is crucial ... Printed circuit boards(PCBs)are representative composite materials,and their high-quality drilling machining remains a persistent challenge in the industry.The finishing of the cutting edge of a microdrill is crucial to drill performance in machining fine-quality holes with a prolonged tool life.The miniature size involving submicron scale geometric dimensions,a complex flute shape,and low fracture toughness makes the cutting edge of microdrills susceptible to breakage and has been the primary limiting factor in edge preparation for microdrills.In this study,a newly developed cutting edge preparation method for microdrills was tested experimentally on electronic printed circuit boards.The proposed method,namely,shear thickening polishing,limited the cutting edge burrs and chipping on the cutting edge,and this in turn transformed the cutting edge’s radius from being sharp to smooth.Moreover,the edge–edge radius could be regulated by adjusting the processing time.PCB drilling experiments were conducted to investigate the influence of different cutting edge radii on wear,hole position accuracy,nail head value,and hole wall roughness.The proposed approach showed 20%enhancement in hole position accuracy,33%reduction in the nail head value,and 19%reduction in hole wall roughness compared with the original microdrill.However,a threshold is needed;without it,excessive shear thickening polishing will result in a blunt edge,which may accelerate the wear of the microdrill.Wear was identified as the primary factor that reduced hole quality.The study indicates that in printed circuit board machining,microdrills should effectively eliminate grinding defects and maintain the sharpness of the cutting edge as much as possible to obtain excellent drilling quality.Overall,shear thickening polishing is a promising method for cutting edge preparation of microdrills.Further research and optimization can lead to additional improvements in microdrill performance and contribute to the continued advancement of printed circuit board manufacturing. 展开更多
关键词 microdrill shear thickening polishing cutting edge preparation electronic printed circuit boards hole quality
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Edge preparation methods for cutting tools:a review
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作者 Yu ZHOU Wei FANG +6 位作者 Lanying SHAO Yanfei DAI Jiahuan WANG Xu WANG Julong YUAN weigang guo Binghai LYU 《Frontiers of Mechanical Engineering》 SCIE CSCD 2023年第4期49-77,共29页
Edge preparation can remove cutting edge defects,such as burrs,chippings,and grinding marks,generated in the grinding process and improve the cutting performance and service life of tools.Various edge preparation meth... Edge preparation can remove cutting edge defects,such as burrs,chippings,and grinding marks,generated in the grinding process and improve the cutting performance and service life of tools.Various edge preparation methods have been proposed for different tool matrix materials,geometries,and application requirements.This study presents a scientific and systematic review of the development of tool edge preparation technology and provides ideas for its future development.First,typical edge characterization methods,which associate the microgeometric characteristics of the cutting edge with cutting performance,are briefly introduced.Then,edge preparation methods for cutting tools,in which materials at the cutting edge area are removed to decrease defects and obtain a suitable microgeometry of the cutting edge for machining,are discussed.New edge preparation methods are explored on the basis of existing processing technologies,and the principles,advantages,and limitations of these methods are systematically summarized and analyzed.Edge preparation methods are classified into two categories:mechanical processing methods and nontraditional processing methods.These methods are compared from the aspects of edge consistency,surface quality,efficiency,processing difficulty,machining cost,and general availability.In this manner,a more intuitive understanding of the characteristics can be gained.Finally,the future development direction of tool edge preparation technology is prospected. 展开更多
关键词 edge preparation method preparation principle cutting edge geometry edge characterization tool performance
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Advancing endoscope for cervicothoracic junction:a feasibility study of small incision-assisted submucosal tunnel endoscopic resection(S-STER)
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作者 Enpan Xu weigang guo +5 位作者 Zhipeng Qi Dongli He Pingxiang Lu Zhanghan Chen Jingyi Liu Yunshi Zhong 《Gastroenterology Report》 SCIE EI 2022年第1期674-676,共3页
Introduction The cervicothoracic junction is a complex and narrow space involving many key neurovascular structures with close associations.Tumors frequently invade or compress surrounding tissues and organs in this r... Introduction The cervicothoracic junction is a complex and narrow space involving many key neurovascular structures with close associations.Tumors frequently invade or compress surrounding tissues and organs in this region,resulting in a risk of injury during surgery[1].There are many surgical approaches to treat tumors of the cervicothoracic junction,but they are associated with high morbidity and mortality[2,3]. 展开更多
关键词 THORACIC ORGANS MORTALITY
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