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食管癌切除患者颈部不同吻合方式发生吻合口瘘影响因素分析 被引量:1
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作者 唐波 赵夏 +3 位作者 刘红兵 张清峰 刘奎 张慧 《中国当代医药》 CAS 2022年第21期18-22,共5页
目的探讨食管癌切除患者颈部不同吻合方式发生吻合口瘘的影响因素。方法回顾性选取2015年1月至2019年12月自贡市第四人民医院胸外科收治的139例食管癌颈部吻合患者作为研究对象。根据吻合方式将其分为器械吻合组(78例)和手工吻合组(61例... 目的探讨食管癌切除患者颈部不同吻合方式发生吻合口瘘的影响因素。方法回顾性选取2015年1月至2019年12月自贡市第四人民医院胸外科收治的139例食管癌颈部吻合患者作为研究对象。根据吻合方式将其分为器械吻合组(78例)和手工吻合组(61例)。分析术前及围手术期资料,比较两种吻合方式的吻合口瘘发生率。根据术后有无吻合口瘘将患者分为吻合口瘘组(18例)和无吻合口瘘组(121例),分析影响吻合口瘘的危险因素。结果单因素分析结果显示,肿瘤部位、吻合方式、肿瘤分期、手术时间、新辅助放化疗是吻合口瘘的相关因素(P<0.05)。多因素分析结果显示,器械吻合(β=0.978,OR=20.322,95%CI=1.343~201.434)、手术时间>300 min(β=2.877,OR=1.150,95%CI=1.101~1.893)是吻合口瘘发生的独立危险因素(P<0.05)。139例患者中,器械吻合的吻合口瘘发生率为19.2%,高于手工吻合的4.9%,差异有统计学意义(P<0.05)。器械吻合中,细管状胃的瘘发生率高于球棒状胃,差异有统计学意义(P<0.05)。结论手术时间、吻合方式是吻合口瘘发生的独立危险因素。手工分层吻合能有效减少颈部吻合口瘘的发生,器械吻合时,采用球棒状胃能降低吻合口瘘的发生。手工分层端端吻合具有胃损伤小,吻合口瘘发生率低的优点,是一种较好的颈部吻合方式。 展开更多
关键词 食管癌切除 颈部吻合 吻合口瘘 端端吻合
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Multi-level cross-layer protocol for end-to-end delay provisioning in wireless multimedia sensor networks
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作者 Hossein HADADIAN NEJAD YOUSEFI Yousef SEIFI KAVIAN Alimorad MAHMOUDI 《Frontiers of Information Technology & Electronic Engineering》 SCIE EI CSCD 2019年第9期1266-1276,共11页
Rapid developments in information and communication technology in recent years have posed a significant challenge in wireless multimedia sensor networks(WMSNs).End-to-end delay and reliability are the critical issues ... Rapid developments in information and communication technology in recent years have posed a significant challenge in wireless multimedia sensor networks(WMSNs).End-to-end delay and reliability are the critical issues in multimedia applications of sensor networks.In this paper we provide a new cross-layer approach for provisioning the end-to-end delay of the network at a desirable level of the packet delivery ratio(PDR),used here as a measure of network reliability.In the proposed multi-level cross-layer(MLCL)protocol,the number of hops away from the sink is used to set a level for each node.A packet is routed through the path with the minimum hop count to the sink using this level setting.The proposed protocol uses cross-layer properties between the network and medium access control(MAC)layers to estimate the minimum delay,with which a node can deliver a packet to the sink.When a node wants to send a packet,the MLCL protocol compares this minimum delay with the time to live(TTL)of a packet.If the TTL of the packet is higher than the minimum delay,the node sends the packet through the path with the minimum delay;otherwise,the node drops the packet as the node cannot deliver it to the sink within the TTL duration.This packet dropping improves network performance because the node can send a useful packet instead of an unusable packet.The results show a superior performance in terms of end-to-end delay and reliability for the proposed protocol compared to state-of-the-art protocols. 展开更多
关键词 Wireless multimedia sensor networks Cross layering Time to live end-to-end delay Quality of service
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Modeling and Simulation Study of Space Data Link Protocol
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作者 Ismail Hababeh Rizik M. H. Al-Sayyed +2 位作者 Ja’far Alqatawna Yousef Majdalawi Marwan Nabelsi 《International Journal of Communications, Network and System Sciences》 2014年第10期440-452,共13页
This research paper describes the design and implementation of the Consultative Committee for Space Data Systems (CCSDS) standards REF _Ref401069962 \r \h \* MERGEFORMAT [1] for Space Data Link Layer Protocol (SDLP). ... This research paper describes the design and implementation of the Consultative Committee for Space Data Systems (CCSDS) standards REF _Ref401069962 \r \h \* MERGEFORMAT [1] for Space Data Link Layer Protocol (SDLP). The primer focus is the telecommand (TC) part of the standard. The implementation of the standard was in the form of DLL functions using C++ programming language. The second objective of this paper was to use the DLL functions with OMNeT++ simulating environment to create a simulator in order to analyze the mean end-to-end Packet Delay, maximum achievable application layer throughput for a given fixed link capacity and normalized protocol overhead, defined as the total number of bytes transmitted on the link in a given period of time (e.g. per second) divided by the number of bytes of application data received at the application layer model data sink. In addition, the DLL was also integrated with Ground Support Equipment Operating System (GSEOS), a software system for space instruments and small spacecrafts especially suited for low budget missions. The SDLP is designed for rapid test system design and high flexibility for changing telemetry and command requirements. GSEOS can be seamlessly moved from EM/FM development (bench testing) to flight operations. It features the Python programming language as a configuration/scripting tool and can easily be extended to accommodate custom hardware interfaces. This paper also shows the results of the simulations and its analysis. 展开更多
关键词 Consultative COMMITTEE for SPACE DATA Systems Standards SPACE DATA Link PROTOCOL Mean end-to-end Packet Delay Maximum Achievable Application layer Throughput Normalized PROTOCOL OVERHEAD Telecommand Spacecrafts SPACE Instruments
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CNNs-based end-to-end asymmetric encrypted communication system
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作者 Yongli An Zebing Hu +1 位作者 Haoran Cai Zhanlin Ji 《Intelligent and Converged Networks》 EI 2023年第4期313-325,共13页
In this paper,we propose an asymmetric encrypted end-to-end communication system based on convolutional neural networks to solve the problem of secure transmission in the end-to-end wireless communication system.The s... In this paper,we propose an asymmetric encrypted end-to-end communication system based on convolutional neural networks to solve the problem of secure transmission in the end-to-end wireless communication system.The system generates a key generator through a convolutional neural network as a bridge.The private and public keys establish a key pair relationship of arbitrary length sequence information.The transmitter and receiver consist of autoencoders based on convolutional neural networks.For data confidentiality requirements,we design the loss function of the end-to-end communication model based on a convolutional neural network.We also design bugs based on different predictions about the information the system eavesdropper has.Simulation results show that the system performs well on additive Gaussian white noise and Rayleigh fading channels.A legitimate party can establish a secure transmission under a designed communication system;an illegal eavesdropper without a key cannot accurately decode it. 展开更多
关键词 end-to-end communication system convolutional neural network asymmetric encryption loss function physical layer security
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