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Application progresses of ultrasound for snakebites and relative complications
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作者 ZHENG Yiyin SHEN Yanyan BIN Wenkai 《中国医学影像技术》 CSCD 北大核心 2024年第8期1258-1261,共4页
Snakebite has become a serious public health problem with high mortality and disability rates.Ultrasound can provide imaging basis for diagnosis and treatment of snakebites and relative complications.The application p... Snakebite has become a serious public health problem with high mortality and disability rates.Ultrasound can provide imaging basis for diagnosis and treatment of snakebites and relative complications.The application progresses of ultrasound in snakebites and complications were reviewed in this article. 展开更多
关键词 snake bites ULTRASONOGRAPHY DIAGNOSIS
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WSN Mobile Target Tracking Based on Improved Snake-Extended Kalman Filtering Algorithm
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作者 Duo Peng Kun Xie Mingshuo Liu 《Journal of Beijing Institute of Technology》 EI CAS 2024年第1期28-40,共13页
A wireless sensor network mobile target tracking algorithm(ISO-EKF)based on improved snake optimization algorithm(ISO)is proposed to address the difficulty of estimating initial values when using extended Kalman filte... A wireless sensor network mobile target tracking algorithm(ISO-EKF)based on improved snake optimization algorithm(ISO)is proposed to address the difficulty of estimating initial values when using extended Kalman filtering to solve the state of nonlinear mobile target tracking.First,the steps of extended Kalman filtering(EKF)are introduced.Second,the ISO is used to adjust the parameters of the EKF in real time to adapt to the current motion state of the mobile target.Finally,the effectiveness of the algorithm is demonstrated through filtering and tracking using the constant velocity circular motion model(CM).Under the specified conditions,the position and velocity mean square error curves are compared among the snake optimizer(SO)-EKF algorithm,EKF algorithm,and the proposed algorithm.The comparison shows that the proposed algorithm reduces the root mean square error of position by 52%and 41%compared to the SOEKF algorithm and EKF algorithm,respectively. 展开更多
关键词 wireless sensor network(WSN)target tracking snake optimization algorithm extended Kalman filter maneuvering target
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Deep Snake协助相关滤波目标跟踪
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作者 李豪 《信息工程大学学报》 2024年第5期538-544,共7页
针对在相关滤波目标跟踪中,对目标尺度观测不准会造成匹配模板更新错误,从而降低目标跟踪的精度的问题,提出一种Deep Snake协助相关滤波的目标跟踪方法。该方法首先利用相关滤波估计目标的初始状态;然后利用Deep Snake得到目标的轮廓,... 针对在相关滤波目标跟踪中,对目标尺度观测不准会造成匹配模板更新错误,从而降低目标跟踪的精度的问题,提出一种Deep Snake协助相关滤波的目标跟踪方法。该方法首先利用相关滤波估计目标的初始状态;然后利用Deep Snake得到目标的轮廓,进而优化目标的尺度。在OTB-2015(成功率70%)和VOT-2019(期望平均覆盖率28.6%)数据集上的实验结果表明:与现有的目标跟踪方法相比,提出的跟踪方法具有较优的跟踪性能。 展开更多
关键词 目标跟踪 相关滤波 主动轮廓模型 目标尺度观测
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适用于多目标图像分割的改进BVF Snake模型
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作者 田原嫄 史伟秋 郭海涛 《图像与信号处理》 2023年第3期211-225,共15页
参数活动轮廓模型(Snake)在计算机视觉和图像处理领域有着广泛的应用。传统的Snake算法存在许多不足,包括计算量大和当存在多目标时不能收敛到特定目标。虽然边界向量场(Boundary Vector Field, BVF) Snake减小了计算量强度,但是当存在... 参数活动轮廓模型(Snake)在计算机视觉和图像处理领域有着广泛的应用。传统的Snake算法存在许多不足,包括计算量大和当存在多目标时不能收敛到特定目标。虽然边界向量场(Boundary Vector Field, BVF) Snake减小了计算量强度,但是当存在多目标时仍然不能收敛到特定目标。本文通过力场分析,确定了BVF Snake不适用于多目标图像分割的原因;通过改进,提出一种改进的方向BVF (directional BVF, DBVF) Snake模型;在该模型中,通过在特定目标内部增加一个点,得到一个方向向量场,来确定Snake的收敛方向,使其在存在多目标时可以收敛到特定目标。本文对DBVF Snake在增大捕捉范围、添加不同噪声两个方面和常见的Snake模型进行了对比分析,同时对声呐图像进行了分割,实验结果证明了本文提出的模型(方法)对多目标图像分割的有效性。 展开更多
关键词 图像分割 snake BVF snake
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基于snake算法的声呐图像轮廓提取方法 被引量:1
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作者 杨卫东 叶长彬 +2 位作者 陈正林 董加和 肖强 《压电与声光》 CAS 北大核心 2023年第5期752-758,共7页
针对成像声呐的水下目标检测问题,提出一种改进的snake目标轮廓提取方法。该方法首先通过构建高斯模型对成像声呐进行目标检测,提高了目标检测能力。其次根据预设目标粗略区域,结合梯度矢量流(GVF)改进的snake算法,实现了目标轮廓的连... 针对成像声呐的水下目标检测问题,提出一种改进的snake目标轮廓提取方法。该方法首先通过构建高斯模型对成像声呐进行目标检测,提高了目标检测能力。其次根据预设目标粗略区域,结合梯度矢量流(GVF)改进的snake算法,实现了目标轮廓的连续提取。仿真试验验证了所提方法的有效性。 展开更多
关键词 snake算法 轮廓提取 高斯模型
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Finite-Time Sideslip Differentiator-Based LOS Guidance for Robust Path Following of Snake Robots 被引量:3
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作者 Yang Xiu Dongfang Li +5 位作者 Miaomiao Zhang Hongbin Deng Rob Law Yun Huang Edmond Q.Wu Xin Xu 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2023年第1期239-253,共15页
This paper presents a finite-time sideslip differentiator-based line-of-sight(LOS)guidance method for robust path following of snake robots.Firstly,finite-time stable sideslip differentiator and adaptive LOS guidance ... This paper presents a finite-time sideslip differentiator-based line-of-sight(LOS)guidance method for robust path following of snake robots.Firstly,finite-time stable sideslip differentiator and adaptive LOS guidance method are proposed to counteract sideslip drift caused by cross-track velocity.The proposed differentiator can accurately observe the cross-track error and sideslip angle for snake robots to avoid errors caused by calculating sideslip angle approximately.In our method,the designed piecewise auxiliary function guarantees the finite-time stability of position errors.Secondly,for the case of external disturbances and state constraints,a Barrier Lyapunov functionbased backstepping adaptive path following controller is presented to improve the robot’s robustness.The uniform ultimate boundedness of the closed-loop system is proved by analyzing stability.Additionally,a gait frequency adjustment-based virtual velocity control input is derived to achieve the exponential convergence of the tangential velocity.At last,the availability and superiority of this work are shown through simulation and experiment results. 展开更多
关键词 Line-of-sight(LOS) path following SIDESLIP snake robot
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Position Errors and Interference Prediction-Based Trajectory Tracking for Snake Robots 被引量:2
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作者 Dongfang Li Yilong Zhang +5 位作者 Ping Li Rob Law Zhengrong Xiang Xin Xu Limin Zhu Edmond Q.Wu 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2023年第9期1810-1821,共12页
This work presents a trajectory tracking control method for snake robots.This method eliminates the influence of time-varying interferences on the body and reduces the offset error of a robot with a predetermined traj... This work presents a trajectory tracking control method for snake robots.This method eliminates the influence of time-varying interferences on the body and reduces the offset error of a robot with a predetermined trajectory.The optimized line-of-sight(LOS)guidance strategy drives the robot’s steering angle to maintain its anti-sideslip ability by predicting position errors and interferences.Then,the predictions of system parameters and viscous friction coefficients can compensate for the joint torque control input.The compensation is adopted to enhance the compatibility of a robot within ever-changing environments.Simulation and experimental outcomes show that our work can decrease the fluctuation peak of the tracking errors,reduce adjustment time,and improve accuracy. 展开更多
关键词 Anti-sideslip COMPENSATION snake robot trajectory tracking
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Placental Abruption Following Snakebites Envenomation: A Case Report and Literature Review
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作者 Kossi Edem Logbo-Akey Kignomon Bingo M’bortche +4 位作者 Pierre Yendoubé Kambote Solim Biou Djato Kibandou Noe Patidi Dédé Régine Diane Ajavon Abdoul-Samadou Aboubakari 《Open Journal of Obstetrics and Gynecology》 CAS 2023年第2期247-251,共5页
Background: Snakebite envenomation in pregnancy is uncommon. It can lead to a poor outcome in both the mother and the fetus. We describe our approach to envenomation in pregnancy based on the currently available evide... Background: Snakebite envenomation in pregnancy is uncommon. It can lead to a poor outcome in both the mother and the fetus. We describe our approach to envenomation in pregnancy based on the currently available evidence. Case: We reported two case of snakebite in the third trimester of pregnancy having caused placental abruption with expelling a fresh still born baby and a live baby. In both cases, consumption coagulopathy occurred. managed by polyvalent anti-snake and blood transfusion. Their investigations became normal and they were discharged of hospitalization. Conclusion: Snakebite envenomation in pregnant is a maternal and fetal emergency. Treatment must be quick and well adapted. 展开更多
关键词 snake Bite Dic Pregnancy Abruption Placenta Intra-Uterine Demise
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Isolation and identification of four pathogenic bacterial strains from edible snake(Elaphe carinata and Ptyas mucosus)farms with pneumonia in China
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作者 Ying Xia Siyu Long +2 位作者 Yuxuan Peng Songkang Qin Yaoqin Shen 《Animal Diseases》 2023年第1期56-61,共6页
This report describes an outbreak and treatment of pneumonia and enteritis in a snake farm with more than 3000 snakes containing Elaphe carinata(one-year-old)and Ptyas mucosus(three-month-old)seedlings in Huanggang,Hu... This report describes an outbreak and treatment of pneumonia and enteritis in a snake farm with more than 3000 snakes containing Elaphe carinata(one-year-old)and Ptyas mucosus(three-month-old)seedlings in Huanggang,Hubei,China.Gentamicin was used once in the early stage as treatment,administered orally with water or feed by owners,but mortality increased.Lobar pneumonia was confirmed by dissection and histopathology in infected snakes.Four main pathogenic bacteria were isolated and identified with culture and 16S rRNA sequencing:Staphylococcus sciuri,Salmonella enteritis,Vagococcus fluvialis and Providencia vermicola.Drug susceptibility tests were performed,and amikacin,gentamicin and cefitriaxone were chosen accordingly.After two rounds of treatment,the clinical signs for Elaphe carinata were under control,and the mortality was close to 0%after treatment.However,treatments for Ptyas mucosus seedlings did not work well,potentially because of poor administration technique and weak body condition. 展开更多
关键词 Staphylococcus sciuri Antimicrobial resistant Edible snakes DERMATITIS
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The peptide fraction of Bothrops jararaca snake venom induces toxicological effects on the male reproductive system after local envenomation in mice
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作者 CARLOS ALBERTO-SILVA ANA CAROLINA DE ARAUJO +1 位作者 RODRIGO SIMÃO BONFIM JOYCE MEIRE GILIO 《BIOCELL》 SCIE 2023年第2期289-295,共7页
Bothrops envenomation is complex and provokes prominent local tissue damage and systemic disturbances,but little is known about their effects on the male reproductive system.After intratesticular injection,the bioacti... Bothrops envenomation is complex and provokes prominent local tissue damage and systemic disturbances,but little is known about their effects on the male reproductive system.After intratesticular injection,the bioactive peptide fraction(Bj-PF)obtained from Bothrops jararaca snake venom changes the structure of different stages of the seminiferous epithelium cycle in adult mice.For the first time,we investigated whether local envenomation of Bj-PF induces toxicological effects on the male reproductive system,particularly on the seminiferous epithelium and Sertoli cells.Male adult mice were treated with 0.24 mg.kg^(-1) by intramuscular(i.m.)injection for 24 h.The testes samples were collected for morphological and morphometric evaluation.The toxicological effects of Bj-PF were also analyzed on mitochondrial metabolism and nitrite(NO2)production in 15P-1 Sertoli cell culture.Bj-PF changed the structure and function of the seminiferous epithelium,particularly the disruption of the epithelium and the presence of degenerated germ cells in the adluminal compartment,but there were no alterations in the basal compartment.Bj-PF increased the thickness of the seminiferous epithelium and decreased the lumen diameter of the tubule.Semiquantitative histological assessment of the degree of tubule degeneration revealed that Bj-PF also increased the number of hypospermatogenic tubules compared to control.Bj-PF reduced NO2 levels in 15P-1 Sertoli cells without changing the mitochondrial metabolism.Overall,the fact that Bj-PF alters the structure and function of the seminiferous epithelium suggests that bioactive peptides found in B.jararaca snake venom can have toxicological effects on the reproductive systems of affected male mice,providing new insight into the biological characteristics of snake venom and therapeutic strategies for envenomation inflammation. 展开更多
关键词 snake venom Bothrops jararaca Reproductive toxicology Seminiferous epithelium
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Review on Preparation and Research of Prescriptions for Snake Bites in Fujian Province
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作者 Weiren SHI 《Medicinal Plant》 CAS 2023年第4期113-118,122,共7页
The history of research and preparation of prescriptions for snake bites in Fujian Province was reviewed, and the process of incorporating snake doctors into the system and the gradual establishment of snake bite trea... The history of research and preparation of prescriptions for snake bites in Fujian Province was reviewed, and the process of incorporating snake doctors into the system and the gradual establishment of snake bite treatment system in Fujian were explored. The composition of several main snake bite preparations in Fujian was preliminarily compared and analyzed to provide reference for the research and development of similar new preparations at present. 展开更多
关键词 Fujian Chinese herbal medicine snake bites REVIEW
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New Snake Genome Study Sheds Light on Limb Loss and Sensory Superpowers
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作者 YAN Fusheng 《Bulletin of the Chinese Academy of Sciences》 2023年第2期99-102,共4页
A sweeping genomic study of snakes,published in Cell,has shed new light on the genetic basis of their unique traits and evolutionary adaptations.An international team,led by Dr.LI Jiatang from the CAS Chengdu Institut... A sweeping genomic study of snakes,published in Cell,has shed new light on the genetic basis of their unique traits and evolutionary adaptations.An international team,led by Dr.LI Jiatang from the CAS Chengdu Institute of Biology(CIB),analyzed the genomes of 25 snake species with a wide diversity,including blind snakes,pythons,and pit vipers.This extensive dataset allowed the researchers to track changes in the snake genome over 117 million years of evolution,and identify genetic modifications linked to limb loss,infrared sensing,asymmetrical lung development,and other distinctive snake features. 展开更多
关键词 snake PYTHON snake
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基于Snake-Net算法的刺绣针法识别
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作者 王敬雪 庄梅玲 《现代纺织技术》 北大核心 2023年第4期236-249,共14页
为有效提取刺绣图像中针法的特征值,实现刺绣针法的分类识别,在分析刺绣针法特点的基础上,提出了点状针法、线状针法和块面状针法的三大针法分类,并以占主体的块面状针法中的齐针、抢针和套针3种基础针法为处理对象,分析对比其针法特征... 为有效提取刺绣图像中针法的特征值,实现刺绣针法的分类识别,在分析刺绣针法特点的基础上,提出了点状针法、线状针法和块面状针法的三大针法分类,并以占主体的块面状针法中的齐针、抢针和套针3种基础针法为处理对象,分析对比其针法特征,构建针法模型。针对刺绣针法图像进行图像纹理细节的增强处理,基于Harris角点检测特征点和Canny轮廓筛选,对传统Snake算法进行改进,形成智能化HC-Snake模型,实现对目标轮廓的智能化识别并提取目标图像的纹理及颜色特征。通过数据的方差分析确定CON sd,IDM sd,E a,E sd,ENT a,ENT sd,COR sd,SM和TM共9个特征指标,建立特征数据集。最后,建立神经网络分类模型,对针法样本进行分类,并对识别模型进行了实例验证。结果表明,该模型可以实现刺绣针法图像的分类,且分类准确率达到93.3%。 展开更多
关键词 刺绣针法 针法模型 HC-snake模型 灰度共生矩阵 颜色矩 BP神经网络
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The SNAKE System: CEMADEN’s Landslide Early Warning System (LEWS) Mechanism
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作者 Marcio Roberto Magalhães de Andrade Cassiano Antonio Bortolozo +8 位作者 Adenilson Roberto Carvalho Harideva Marturano Egas Klaifer Garcia Daniel Metodiev Tulius Dias Nery Carla Prieto Tristan Pryer Silvia Midori Saito Graziela Scofield 《International Journal of Geosciences》 2023年第11期1146-1159,共14页
In Brazil, the prominent climate-induced disasters are floods and mass movements, with the latter being the most lethal. The spate of major landslide events, especially those in 2011, catalyzed the creation of CEMADEN... In Brazil, the prominent climate-induced disasters are floods and mass movements, with the latter being the most lethal. The spate of major landslide events, especially those in 2011, catalyzed the creation of CEMADEN (National Center for Monitoring and Early Warning of Natural Disasters). This article introduces one of CEMADEN’s pivotal systems for early landslide warnings and traces its developmental timeline. The highlighted SNAKE System epitomizes advancements in digital monitoring, forecasting, and alert mechanisms. By leveraging precipitation data from pluviometers in observed municipalities, the system bolsters early warnings related to potential mass movements, like planar slides and debris flows. Its deployment in CEMADEN’s Situation Room attests to its suitability for overseeing high-risk municipalities, attributed primarily to its robustness and precision. 展开更多
关键词 Natural Disasters Landslide Early Warning System (LEWS) snake System CEMADEN Brazil
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基于PI3K/Akt通路研究蛇伤胶囊调节血小板活化功能治疗竹叶青蛇伤凝血障碍机制
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作者 邵丹 吴晖 +3 位作者 梁志奇 王榕 陈宏杰 文丹 《中国医药指南》 2024年第3期8-10,15,共4页
目的基于PI3K/Akt通路研究蛇伤胶囊调节血小板活化功能治疗竹叶青蛇伤凝血障碍机制。方法24只新西兰大白兔被随机分为正常对照组、模型组、蛇伤胶囊组,每组8只雌雄各半,根据前期研究方法模型组和蛇伤胶囊组以兔耳缘静脉注射0.75 mg/kg... 目的基于PI3K/Akt通路研究蛇伤胶囊调节血小板活化功能治疗竹叶青蛇伤凝血障碍机制。方法24只新西兰大白兔被随机分为正常对照组、模型组、蛇伤胶囊组,每组8只雌雄各半,根据前期研究方法模型组和蛇伤胶囊组以兔耳缘静脉注射0.75 mg/kg竹叶青蛇毒液,建立竹叶青蛇伤兔模型,正常对照组注射等量生理盐水。注射后6 h后予正常对照组和模型组以10 ml/(kg·d)生理盐水灌胃,蛇伤胶囊组予10 ml/(kg·d)蛇伤胶囊所配药液灌胃。以上3组连续灌胃1周后兔耳缘静脉采血5 ml,血小板分离提取后Western blot检测各组血小板细胞PTEN、PI3K、Akt蛋白表达,qPCR检测各组血小板活化指标CD62P mRNA表达。结果与正常对照组相比,模型组血小板细胞PTEN蛋白表达增加(P<0.01),PI3K、Akt蛋白及CD62P mRNA表达减少(P<0.01);与模型组相比,蛇伤胶囊组血小板细胞PTEN蛋白表达减少(P<0.01),PI3K、Akt蛋白及CD62P mRNA表达增加(P<0.01)。结论蛇伤胶囊可通过上调PI3K/Akt通路,改善竹叶青蛇伤导致的血小板活化功能受抑制,从而治疗竹叶青蛇伤凝血障碍。 展开更多
关键词 竹叶青蛇 蛇伤胶囊 血小板活化 PI3K/AKT通路
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DNA条形码技术在蛇类鉴别中的应用
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作者 李晓冰 方来杉 +4 位作者 陈洪博 吴琼 尹会方 林秀娇 李焰 《湖南农业大学学报(自然科学版)》 CAS CSCD 北大核心 2024年第3期35-40,共6页
从NCBI中GenBank数据库下载蛇类细胞色素b基因(Cytb)序列7329条,以MT765098.1序列为标准进行对比和修剪,获得蛇类Cytb序列4665条。对蛇类Cytb序列进行核苷酸饱和度、遗传多样性、种内和种间遗传距离计算,构建系统发育树。结果表明,基于K... 从NCBI中GenBank数据库下载蛇类细胞色素b基因(Cytb)序列7329条,以MT765098.1序列为标准进行对比和修剪,获得蛇类Cytb序列4665条。对蛇类Cytb序列进行核苷酸饱和度、遗传多样性、种内和种间遗传距离计算,构建系统发育树。结果表明,基于Kimura–2–Parameter模型,蛇类平均种内遗传距离为3.3%,普遍小于6.7%,而平均种间遗传距离为19.96%,普遍高于9.3%,说明蛇类物种间遗传距离存在较大差异。根据蛇类物种间遗传距离,识别出蛇类23个物种的亚种,Pareas和Hydrophis属物种含有复合体,Atractus dunni、A.iridescen和A.occidentali互为姐妹物种。 展开更多
关键词 细胞色素B基因 DNA条形码 遗传距离
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长蛇灸联合熏洗包熏蒸治疗气滞血瘀型腰椎间盘突出症对患者疼痛介质及炎症因子的影响 被引量:2
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作者 吕明芳 朱小燕 +1 位作者 万康敏 胡秀武 《中国医学创新》 CAS 2024年第15期76-80,共5页
目的:探讨长蛇灸联合熏洗包熏蒸在腰椎间盘突出症(气滞血瘀型)患者治疗中的应用价值,观察其对炎症因子、疼痛介质水平的影响。方法:将2019年6月—2020年12月因腰椎间盘突出症于南昌市洪都中医院就诊且中医证型属于气滞血瘀型的90例患者... 目的:探讨长蛇灸联合熏洗包熏蒸在腰椎间盘突出症(气滞血瘀型)患者治疗中的应用价值,观察其对炎症因子、疼痛介质水平的影响。方法:将2019年6月—2020年12月因腰椎间盘突出症于南昌市洪都中医院就诊且中医证型属于气滞血瘀型的90例患者纳入研究,用随机数字表法将患者分为对照组、观察A组、观察B组,各30例。对照组予硬膜外封闭治疗,观察A组予硬膜外封闭治疗+熏洗包熏蒸治疗治疗,观察B组予硬膜外封闭治疗+熏洗包熏蒸+长蛇灸治疗。治疗2周后比较临床效果。结果:治疗后,三组血清肿瘤坏死因子-α(tumor necrosis factor-α,TNF-α)、超敏C反应蛋白(hypersensitive C reactive protein,hs-CRP)、白介素-1β(interleukin-1,IL-1β)、血清前列腺素E2(prostaglandin E2,PGE2)、5-羟色胺(5-hydroxytryptamine,5-HT)水平均较治疗前降低,观察B组均低于观察A组、对照组,观察A组上述指标水平均低于对照组,差异均有统计学意义(P<0.05)。治疗后三组视觉模拟评分法(visual analogue scale,VAS)评分均降低,日本骨科协会(Japanese orthopaedic association,JOA)评分及血清β-内啡肽(β-endorphin,β-EP)均较治疗前升高,观察B组VAS评分数值水平低于观察A组、对照组,JOA评分及β-EP数值水平则均高于观察A组及对照组,观察A组VAS评分水平低于对照组,JOA评分及β-EP数值则均更高,差异均有统计学意义(P<0.05)。结论:对于腰椎间盘突出症(气滞血瘀型)患者而言采用长蛇灸联合熏洗包熏蒸可减轻炎症反应,降低疼痛介质,改善临床症状及腰椎功能,安全性高,有助于临床效果提高。 展开更多
关键词 长蛇灸 中药熏蒸 气滞血瘀型 腰椎间盘突出症 疼痛介质 炎症因子
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多策略融合的蛇优化算法及其应用 被引量:1
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作者 王永贵 赵炀 +1 位作者 邹赫宇 胡鹏程 《计算机应用研究》 CSCD 北大核心 2024年第1期134-141,共8页
针对蛇算法寻优阶段交互性差,初始种群随机程度严重,易陷入局部最优解等问题,提出了一种多策略融合的蛇优化算法(multi-strategy snake optimizer, MSSO)。首先,利用正交矩阵对蛇种群进行初始化,使个体分布更加均匀;其次,设计探索开发... 针对蛇算法寻优阶段交互性差,初始种群随机程度严重,易陷入局部最优解等问题,提出了一种多策略融合的蛇优化算法(multi-strategy snake optimizer, MSSO)。首先,利用正交矩阵对蛇种群进行初始化,使个体分布更加均匀;其次,设计探索开发阶段切换的自适应方程,用以替换原有的食物量与温度阈值,使算法进行自适应阶段切换;最后,使用联合反向选择策略替换算法原有的新个体孵化方法,提高算法收敛精度的同时加快算法收敛效率。选取10个基准测试函数从不同角度对MSSO算法进行实验,测试算法性能,分析各策略的有效性,并使用Wilcoxon秩和检验来证明算法显著性,通过两个工程应用仿真实验来验证MSSO的实用性。各实验结果表明MSSO较比较算法综合表现更优,证明MSSO算法改进在寻优能力、鲁棒性、实用性等方面均有所提升。 展开更多
关键词 蛇优化算法 正交矩阵初始化 自适应阶段切换 联合反向选择 元启发算法 工程应用问题
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基于ISO-TW算法的多仓储机器人路径规划研究
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作者 周小青 童一飞 周开俊 《现代制造工程》 CSCD 北大核心 2024年第9期54-59,143,共7页
针对当前智能仓库中多仓储机器人协同规划效率低下、动态性不足等问题,提出了一种融合改进蛇优化(Improved Snake Optimizer,ISO)算法和时间窗(Time Window,TW)模型的路径规划方法。首先,在静态规划阶段,利用考虑阻塞因素的改进蛇优化... 针对当前智能仓库中多仓储机器人协同规划效率低下、动态性不足等问题,提出了一种融合改进蛇优化(Improved Snake Optimizer,ISO)算法和时间窗(Time Window,TW)模型的路径规划方法。首先,在静态规划阶段,利用考虑阻塞因素的改进蛇优化算法为多仓储机器人规划出全局最优路径,同时计算出各机器人的时间窗,从而提升仓储机器人的规划效率;其次,在动态规划阶段,通过建立的多仓储机器人时间窗模型并引入动态调节策略,以消解冲突提升算法的动态性能;最后,进行仿真及实验。仿真结果表明,ISO-TW算法相较其他算法在阻塞点数量上最多可减少27~43个,减少幅度达22.50%~31.62%(机器人规模为80个);重规划路径比重可降低39.82%~41.05%(机器人规模为40个);平均运行时长最多可缩短38~40 s,缩短幅度约为18.27%~19.05%(机器人规模为60个)。实验结果表明,ISO-TW算法较其他算法平均运行时长减少8.53%~9.23%,冲突次数减少11.63%~15.56%,能够在真实场景中实现多仓储机器人的高效协同规划。 展开更多
关键词 蛇优化算法 时间窗 仓储机器人 路径规划
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缺血性脊髓病的临床和影像学特征分析
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作者 矫黎东 贾宇 宋旸 《北京医学》 CAS 2024年第5期366-369,373,共5页
目的总结缺血性脊髓病的临床和影像学特征。方法选取2015—2023年被误诊为急性脊髓炎,并于首都医科大学宣武医院最终确诊为缺血性脊髓病患者5例,回顾性分析患者的临床资料,总结患者的临床症状和影像学特点。结果5例患者中,男2例、女3例... 目的总结缺血性脊髓病的临床和影像学特征。方法选取2015—2023年被误诊为急性脊髓炎,并于首都医科大学宣武医院最终确诊为缺血性脊髓病患者5例,回顾性分析患者的临床资料,总结患者的临床症状和影像学特点。结果5例患者中,男2例、女3例,中位发病年龄59岁,均为急性起病,表现为肢体无力、麻木等脊髓损害症状。5例患者的脊髓MRI示髓内异常信号,其中颈髓病变4例、腰膨大病变1例;轴位影像均出现典型“蛇眼征”特点5例,其中2例患者矢状位影像表现为“铅笔征”。患者发病早期应用免疫治疗后效果不佳。入院明确诊断后,给予抗凝或抗血小板药物治疗及脊髓功能康复治疗,症状有不同程度改善,但由于治疗延迟,均遗留肢体无力或麻木症状。结论脊髓髓内异常信号的特殊征象“蛇眼征”和“铅笔征”可作为缺血性脊髓病和急性脊髓炎的影像学重要鉴别要点。应提高以急性起病的脊髓损害症状患者特殊影像学征象的识别能力。 展开更多
关键词 缺血性脊髓病 急性脊髓炎 蛇眼征
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