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基于PatchTracker的对抗补丁防御算法 被引量:1
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作者 肖镇杰 黄诗瑀 +2 位作者 叶锋 黄丽清 黄添强 《网络与信息安全学报》 2024年第1期169-180,共12页
基于深度神经网络的目标检测技术已经广泛应用于各领域,然而,通过对抗补丁攻击在图像中添加局部扰动,以此来误导深度神经网络,对基于目标检测技术的视觉系统构成了严重威胁。针对这一问题,利用对抗补丁和图像背景的语义差异性,提出了一... 基于深度神经网络的目标检测技术已经广泛应用于各领域,然而,通过对抗补丁攻击在图像中添加局部扰动,以此来误导深度神经网络,对基于目标检测技术的视觉系统构成了严重威胁。针对这一问题,利用对抗补丁和图像背景的语义差异性,提出了一种基于PatchTracker的对抗补丁防御算法,该算法由上游补丁检测器与下游数据增强模块组成。上游补丁检测器使用带有注意力机制的YOLOV5(you only look once-v5)确定对抗补丁所在位置,有助于提高对小尺度对抗补丁的检测精度;将检测区域用合适的像素值覆盖以抹除对抗补丁,上游补丁检测器不仅能够有效降低对抗样本的攻击性,而且不依赖大规模的训练数据;下游数据增强模块通过改进模型训练范式,提高下游目标检测器的鲁棒性;将抹除补丁后的图像输入经过数据增强的下游YOLOV5目标检测模型。在公开的TT100K交通标志数据集上进行了交叉验证,实验表明,与未采取防御措施相比,所提算法能够有效防御多种类型的通用对抗补丁攻击,在检测对抗补丁图像时的mAP(mean average precision)提高65%左右,有效地改善了小尺度对抗补丁的漏检情况。与现有算法比较,所提算法有效提高了神经网络在检测对抗样本时的准确率。此外,所提算法不涉及下游模型结构的修改,具有良好的兼容性。 展开更多
关键词 深度学习安全 对抗攻击与防御 对抗补丁 目标检测
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Scheme Based on Multi-Level Patch Attention and Lesion Localization for Diabetic Retinopathy Grading 被引量:1
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作者 Zhuoqun Xia Hangyu Hu +4 位作者 Wenjing Li Qisheng Jiang Lan Pu Yicong Shu Arun Kumar Sangaiah 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第7期409-430,共22页
Early screening of diabetes retinopathy(DR)plays an important role in preventing irreversible blindness.Existing research has failed to fully explore effective DR lesion information in fundus maps.Besides,traditional ... Early screening of diabetes retinopathy(DR)plays an important role in preventing irreversible blindness.Existing research has failed to fully explore effective DR lesion information in fundus maps.Besides,traditional attention schemes have not considered the impact of lesion type differences on grading,resulting in unreasonable extraction of important lesion features.Therefore,this paper proposes a DR diagnosis scheme that integrates a multi-level patch attention generator(MPAG)and a lesion localization module(LLM).Firstly,MPAGis used to predict patches of different sizes and generate a weighted attention map based on the prediction score and the types of lesions contained in the patches,fully considering the impact of lesion type differences on grading,solving the problem that the attention maps of lesions cannot be further refined and then adapted to the final DR diagnosis task.Secondly,the LLM generates a global attention map based on localization.Finally,the weighted attention map and global attention map are weighted with the fundus map to fully explore effective DR lesion information and increase the attention of the classification network to lesion details.This paper demonstrates the effectiveness of the proposed method through extensive experiments on the public DDR dataset,obtaining an accuracy of 0.8064. 展开更多
关键词 DDR dataset diabetic retinopathy lesion localization multi-level patch attention mechanism
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Patch-Locator:一种基于排序学习的开源软件漏洞补丁定位方法
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作者 杨云帆 薄莉莉 +2 位作者 魏颖 吴潇雪 孙小兵 《小型微型计算机系统》 CSCD 北大核心 2024年第10期2551-2560,共10页
日益增多的开源软件漏洞对软件安全带来了巨大的风险,补丁在应对这一风险的过程中扮演了非常重要的角色.不幸的是,尽管大部分漏洞的补丁在被披露前就已经开发完毕,但仅有部分补丁会随漏洞同步公开.现有的研究发现了漏洞与其补丁之间存... 日益增多的开源软件漏洞对软件安全带来了巨大的风险,补丁在应对这一风险的过程中扮演了非常重要的角色.不幸的是,尽管大部分漏洞的补丁在被披露前就已经开发完毕,但仅有部分补丁会随漏洞同步公开.现有的研究发现了漏洞与其补丁之间存在一定的相关性,并基于这些相关性特征对提交进行了排序,以定位漏洞的补丁,但仍旧存在漏洞数据部分缺失、定位准确率不佳等问题.本文提出了Patch-Locator,一种新的基于排序学习的补丁定位方法,通过扩展漏洞数据源对漏洞数据进行补充,并根据漏洞与补丁文本的相似性、漏洞产生的原因和导致的结果等更能反映漏洞与补丁间关联的因素提取了更具有针对性的相关性特征,并使用LambdaMart排序学习模型对提交基于其具有的相关性特征进行排序以定位安全补丁.本文用来自10个开源软件项目的1669个漏洞来评估Patch-Locator.实验结果表明,Patch-Locator的Recall@1指标为92.22%,Recall@5指标为95.51%,Manual Effort@5指标为1.2455,均优于现有方法. 展开更多
关键词 开源软件 安全补丁 排序学习 补丁定位
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Mechanobiomaterials:Mechanics-Guided Design of Epicardial Patch for Treating
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作者 Huajian Gao 《医用生物力学》 CAS CSCD 北大核心 2024年第S01期1-1,共1页
In recent years,the field of mechanomaterials has emerged at the interface of mechanics,materials science,biology,medicine and data science,where materials are proactively designed or programmed to achieve targeted fu... In recent years,the field of mechanomaterials has emerged at the interface of mechanics,materials science,biology,medicine and data science,where materials are proactively designed or programmed to achieve targeted functionalities by leveraging the fundamental mechanics principles and force-geometry-property relationships.In the biological context,one may likewise introduce mechanobiomaterials as a field with the following goals:(1)proactive design or programming of materials for precisely mediating biomechanical environment of living systems for tissue repair/restoration;(2)proactive control/programming of living systems themselves by an external field via force-structure-function relationships.Here,we will discuss an example of research in mechanobiomaterials on using mechanics to guide the design of acellular epicardial patches for the treatment of myocardial infarction.This technology aims to employ a biocompatible material patch to help reverse left ventricular remodeling and restore heart function after myocardial infarction by increasing the mechanical integrity of damaged heart tissues.However,its application is currently limited by widely scattered therapeutic efficacy.Here,we develop a biomechanics-based simulation platform that allows us to test,design and optimize the performance of an epicardial patch.We show that the widely scattered therapeutic efficacy of this technology can be attributed to a“pre-strain sensitivity”caused by attaching an elastic patch to a dynamically beating heart.To mitigate this challenge,we introduce a viscoelastic epicardial patch,designed at the so-called‘gel point’of the material,that effectively accommodates the cyclic deformation of the myocardium.This then leads to the fabrication and experimentally validated epicardial patch that outperforms all existing ones in restoring heart function after both acute and subacute myocardial infarction in rats.Our study also demonstrates the potential of employing viscoelastic interfaces for better integration of synthetic materials with biological tissues. 展开更多
关键词 patch BIOMATERIALS SCATTERED
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Formation and ecological response of sand patches in the protection system of Shapotou section of the Baotou-Lanzhou railway,China
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作者 DUN Yaoquan QU Jianjun +4 位作者 KANG Wenyan LI Minlan LIU Bin WANG Tao SHAO Mei 《Journal of Arid Land》 SCIE CSCD 2024年第2期298-313,共16页
The development of bare patches typically signifies a process of ecosystem degradation.Within the protection system of Shapotou section of the Baotou-Lanzhou railway,the extensive emergence of bare sand patches poses ... The development of bare patches typically signifies a process of ecosystem degradation.Within the protection system of Shapotou section of the Baotou-Lanzhou railway,the extensive emergence of bare sand patches poses a threat to both stability and sustainability.However,there is limited knowledge regarding the morphology,dynamic changes,and ecological responses associated with these sand patches.Therefore,we analyzed the formation and development process of sand patches within the protection system and its effects on herbaceous vegetation growth and soil nutrients through field observation,survey,and indoor analysis methods.The results showed that sand patch development can be divided into three stages,i.e.,formation,expansion,and stabilization,which correspond to the initial,actively developing,and semi-fixed sand patches,respectively.The average dimensions of all sand patch erosional areas were found to be 7.72 m in length,3.91 m in width,and 0.32 m in depth.The actively developing sand patches were the largest,and the initial sand patches were the smallest.Throughout the stage of formation and expansion,the herbaceous community composition changed,and the plant density decreased by more than 50.95%.Moreover,the coverage and height of herbaceous plants decreased in the erosional area and slightly increased in the depositional lobe;and the fine particles and nutrients of soils in the erosional area and depositional lobe showed a decreasing trend.In the stabilization phases of sand patches,the area from the inlet to the bottom of sand patches becomes initially covered with crusts.Vegetation and 0-2 cm surface soil condition improved in the erosional area,but this improvement was not yet evident in the depositional lobe.Factors such as disturbance,climate change,and surface resistance to erosion exert notable influences on the formation and dynamics of sand patches.The results can provide evidence for the future treatment of sand patches and the management of the protection system of Shapotou section of the Baotou-Lanzhou railway. 展开更多
关键词 railway protection system sand patch MORPHOLOGY vegetation characteristic soil property
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Do brood parasitic Common Cuckoos develop brood patches during the breeding season?
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作者 Jun-Seo Go Hae-Ni Kim +3 位作者 Sue-Jeong Jin Myeong-Chan Cha Heesoo Lee Jin-Won Lee 《Avian Research》 SCIE CSCD 2024年第3期363-368,共6页
Many birds develop brood patches on their ventral apterium under hormonal regulation to effectively transmit body heat to eggs during incubation.The developed patch has several characteristics,including de-feathering,... Many birds develop brood patches on their ventral apterium under hormonal regulation to effectively transmit body heat to eggs during incubation.The developed patch has several characteristics,including de-feathering,vascularization,and edema.However,little is known about whether avian brood parasites that do not incubate their eggs exhibit brood patch development during the breeding season.In this study,we measured the size of the ventral apterium in 114 Common Cuckoos(Cuculus canorus)captured in the field throughout the breeding season and examined the appearance of the ventral apterium to confirm the development of brood patches.We also examined whether morphological traits and various factors correlated with the size of the ventral apterium(sternal apterium and abdominal apterium)and how it changed during the breeding season.We found no clear signs of brood patch development in Common Cuckoos captured throughout the breeding season,indicating that they likely did not develop brood patches on the ventral apterium during this period.We also found that ventral apterium size was positively correlated with wing length and body weight.In addition,Common Cuckoos with newly growing feathers on the boundary of the ventral apterium with pteryla were frequently observed as seasons progressed to the end.In conclusion,Common Cuckoos exhibit neither brood patch development nor the vestigial characteristics of ancestral brood patches,except for the growth of feathers on boundary the ventral apterium.Further studies examining brood patches across different groups of avian brood parasites are valuable for enhancing our understanding of the developmental and physiological adaptations of avian brood parasites. 展开更多
关键词 Brood parasitism Brood patch Common Cuckoo Pterylosis Re-feathering Ventral apterium
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Treatment of 198 Cases of Thyroid Nodules with Sanying Capsule Combined with Xiaoying Patch
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作者 Shujing SHI Mingyue YANG +2 位作者 Yue HAO Haihui ZHU Yan QIN 《Medicinal Plant》 2024年第3期56-59,共4页
[Objectives]To observe the clinical efficacy of Sanying capsule combined with Xiaoying Patch in treating thyroid nodule(TN).[Methods]Two groups were treated similarly,with 200 cases in the control group undergoing bas... [Objectives]To observe the clinical efficacy of Sanying capsule combined with Xiaoying Patch in treating thyroid nodule(TN).[Methods]Two groups were treated similarly,with 200 cases in the control group undergoing basic treatment for 12 weeks and 198 cases in the observation group receiving Sanying capsule combined with Xiaoying patches for the same duration.The clinical symptoms,number of nodules,diameter of the largest nodule,and maximum reduction of nodules were observed before and after treatment.A control analysis was performed,and the underlying mechanisms were explored.[Results]The primary symptoms of the observation group exhibited a more favorable improvement than those of the control group.Additionally,the number of nodules decreased,the diameter of the largest nodule decreased,and the maximum reduction of nodules decreased in both groups following treatment.However,the observation group demonstrated a more pronounced improvement than the control group(P<0.05).[Conclusions]The combination of Sanying capsule and Xiaoying patch has been demonstrated to be an effective treatment for TN,with a high degree of reliability in terms of safety. 展开更多
关键词 THYROID NODULE Sanying CAPSULE Xiaoying patch Clinical EFFICACY
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Ginger oil-loaded transdermal adhesive patch treats post-traumatic stress disorder
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作者 Xingshuang Song Yizhi Zhang +7 位作者 Ziyan Tang Jing Dai Yanping Wu Guiyu Huang Hong Niu Yaxin Wang Xu Jin Lina Du 《Journal of Traditional Chinese Medical Sciences》 CAS 2024年第3期316-329,共14页
Objective:To find a viable alternative to reduce the number of doses required for the patients with post-traumatic stress disorder(PTSD),and to improve efficacy and patient compliance.Methods: In this study,we used gi... Objective:To find a viable alternative to reduce the number of doses required for the patients with post-traumatic stress disorder(PTSD),and to improve efficacy and patient compliance.Methods: In this study,we used ginger oil,a phytochemical with potential therapeutic properties,to prepare ginger oil patches.High-performance liquid chromatography(HPLC)was used to quantify the main active component of ginger oil,6-gingerol.Transdermal absorption experiments were conducted to optimize the various pressure-sensitive adhesives and permeation enhancers,including their type and concentration.Subsequently,the ginger oil patches were optimized and subjected to content determination and property evaluations.A PTSD mouse model was established using the foot-shock method.The therapeutic effect of ginger oil patches on PTSD was assessed through pathological sections,behavioral tests,and the evaluation of biomarkers such as tumor necrosis factor-α(TNF-α),interleukin-6(IL-6),brain-derived neurotrophic factor(BDNF),and melatonin(MT).Results: The results demonstrated that ginger oil patches exerted therapeutic effects against PTSD by inhibiting inflammatory responses and modulating MT and BDNF levels.Pharmacokinetic experiments revealed that ginger oil patches maintained a stable blood drug concentration for at least one day,addressing the rapid metabolism drawback of 6-gingerol and enhancing its therapeutic efficacy.Conclusions: Ginger oil can be prepared as a transdermal drug patch that meets these requirements,and the bioavailability of the prepared patch is better than that of oral administration.It can improve PTSD with good patient compliance and ease of administration.Therefore,it is a promising therapeutic formulation for the treatment of PTSD. 展开更多
关键词 Post-traumatic stress disorder 6-GINGEROL Pressure sensitive adhesive patch Transdermal delivery
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Unveiling the adaptation strategies of woody plants in remnant forest patches to spatiotemporal urban expansion through leaf trait networks
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作者 Mengping Jian Jingyi Yang 《Forest Ecosystems》 SCIE CSCD 2024年第2期247-254,共8页
Background:With the expansion of urban areas,the remnants of forested areas play a crucial role in preserving biodiversity in urban environments.This study aimed to explore the impact of spatiotemporal urban expansion... Background:With the expansion of urban areas,the remnants of forested areas play a crucial role in preserving biodiversity in urban environments.This study aimed to explore the impact of spatiotemporal urban expansion on the networks of leaf traits in woody plants within remnant forest patches,thereby enhancing our understanding of plant adaptive strategies and contributing to the conservation of urban biodiversity.Methods:Our study examined woody plants within 120 sample plots across 15 remnant forest patches in Guiyang,China.We constructed leaf trait networks (LTNs) based on 26 anatomical,structural,and compositional leaf traits and assessed the effects of the spatiotemporal dynamics of urban expansion on these LTNs.Results and conclusions:Our results indicate that shrubs within these patches have greater average path lengths and diameters than trees.With increasing urban expansion intensity,we observed a rise in the edge density of the LTN-shrubs.Additionally,modularity within the networks of shrubs decreased as road density and urban expansion intensity increased,and increases in the average path length and average clustering coefficient for shrubs were observed with a rise in the composite terrain complexity index.Notably,patches subjected to‘leapfrog’expansion exhibited greater average patch length and diameter than those experiencing edge growth.Stomatal traits were found to have high degree centrality within these networks,signifying their substantial contribution to multiple functions.In urban remnant forests,shrubs bolster their resilience to variable environmental pressures by augmenting the complexity of their leaf trait networks. 展开更多
关键词 Urban remnant forest patch Woody plant Leaf trait network Plant adaptation strategy Spatiotemporal urban expansion
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Deep Global Multiple-Scale and Local Patches Attention Dual-Branch Network for Pose-Invariant Facial Expression Recognition
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作者 Chaoji Liu Xingqiao Liu +1 位作者 Chong Chen Kang Zhou 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第4期405-440,共36页
Pose-invariant facial expression recognition(FER)is an active but challenging research topic in computer vision.Especially with the involvement of diverse observation angles,FER makes the training parameter models inc... Pose-invariant facial expression recognition(FER)is an active but challenging research topic in computer vision.Especially with the involvement of diverse observation angles,FER makes the training parameter models inconsistent from one view to another.This study develops a deep global multiple-scale and local patches attention(GMS-LPA)dual-branch network for pose-invariant FER to weaken the influence of pose variation and selfocclusion on recognition accuracy.In this research,the designed GMS-LPA network contains four main parts,i.e.,the feature extraction module,the global multiple-scale(GMS)module,the local patches attention(LPA)module,and the model-level fusion model.The feature extraction module is designed to extract and normalize texture information to the same size.The GMS model can extract deep global features with different receptive fields,releasing the sensitivity of deeper convolution layers to pose-variant and self-occlusion.The LPA module is built to force the network to focus on local salient features,which can lower the effect of pose variation and self-occlusion on recognition results.Subsequently,the extracted features are fused with a model-level strategy to improve recognition accuracy.Extensive experimentswere conducted on four public databases,and the recognition results demonstrated the feasibility and validity of the proposed methods. 展开更多
关键词 Pose-invariant FER global multiple-scale(GMS) local patches attention(LPA) model-level fusion
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Observing eddy dye patches induced by shear instabilities in the surf zone on a plane beach
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作者 Chunping Ren Nannan Fu +2 位作者 Chong Yu Yuchuan Bai Kezhao Fang 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2024年第3期15-29,共15页
The effects of surf zone eddy generated by alongshore currents on the deformation and transport of dye are still poorly understood,and related tracer release experiments are lacking.Therefore,a tracer release laborato... The effects of surf zone eddy generated by alongshore currents on the deformation and transport of dye are still poorly understood,and related tracer release experiments are lacking.Therefore,a tracer release laboratory experiment was conducted under monochromatic,unidirectional incident waves with a large incident angle(30°)on a plane beach with a 1:100 slope in a large wave basin.A charge-coupled device suspended above the basin recorded the dye patch image.The evolution of eddy dye patch was observed and the transport and diffusion were analyzed based on the collected images.Subsequently,a linear instability numerical model was adopted to calculate the perturbation velocity field at the initial stage.The observation and image processing results show that surf zone eddy patches occurred and were separated from the original dye patches.Our numerical analysis results demonstrate that the structure of the perturbation velocity field is consistent with the experimental observations,and that the ejection of eddy patches shoreward or offshore may be ascribed to the double vortex. 展开更多
关键词 surf zone tracer release experiment evolution of eddy patch shear instability of alongshore currents
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Evaluation of the Efficacy of Auricular Acupoint Pressure Patch Combined with Modified Huangqi Decoction in Treating Diabetic Nephropathy
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作者 Ying Wang 《Journal of Clinical and Nursing Research》 2024年第1期45-50,共6页
Objective:To explore the efficacy of auricular acupoint pressure patch combined with modified Huangqi Decoction in treating diabetic nephropathy.Methods:60 patients with diabetic nephropathy treated in our hospital fr... Objective:To explore the efficacy of auricular acupoint pressure patch combined with modified Huangqi Decoction in treating diabetic nephropathy.Methods:60 patients with diabetic nephropathy treated in our hospital from January 2021 to December 2022 were selected for this study.The patients were randomly divided into two groups using the random number table method,with 30 patients in each group.Among them,the control group was treated with conventional Western medicine,while the experimental group was treated with auricular acupoint pressure patches combined with modified Huangqi Decoction.The patients’fasting blood glucose(FPG),2-hour postprandial blood glucose(2hPG),glycated hemoglobin(HbA1c),urinary protein quantification,urea nitrogen(BUN),serum creatinine(SCr),and other indicators were detected and recorded before and after treatment.Results:Before treatment,there was no statistically significant difference in the FPG,the 2hPG,and the HbA1c between the two groups of patients(P>0.05);after treatment,the FPG,the 2hPG,and the HbA1c of the patients in the experimental group were significantly lower than those in the control group(P<0.05).Before treatment,there was no statistically significant difference in the urinary protein quantification,the BUN,and the SCr between the two groups of patients(P>0.05);after treatment,the urinary protein quantification,BUN,and SCr of the patients in the experimental group were significantly lower than those in the control group(P<0.05).The experimental group showed better improvement in symptoms such as fatigue,backache,and frequency of nocturia(P<0.05).Conclusion:Auricular acupoint pressure patch combined with modified Huangqi Decoction effectively treats diabetic nephropathy and it helps control blood sugar and renal function indicators and improve clinical symptoms,therefore improving the patients’quality of life. 展开更多
关键词 Auricular acupoint pressure patch Modified Huangqi Decoction Diabetic nephropathy
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A Simple Egg Membrane Patch Bridging Method for Repairing Tympanic Membrane Perforation
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作者 Xing Huang Xuping Wang +2 位作者 Bin Li Lumei Shao Ping Li 《Journal of Clinical and Nursing Research》 2024年第8期264-269,共6页
Objective:To analyze the clinical effect of a simple egg membrane patch bridging method in repairing tympanic membrane perforation.Methods:A total of 93 tympanic membrane perforation patients admitted to the hospital ... Objective:To analyze the clinical effect of a simple egg membrane patch bridging method in repairing tympanic membrane perforation.Methods:A total of 93 tympanic membrane perforation patients admitted to the hospital between September 2022 and October 2023 were selected and divided into two groups according to the random number table method.The control group implemented the conventional treatment(n=46 cases),and the patch group adopted the simple egg membrane patch bridging method(n=47 cases).The healing rate of the tympanic membrane,the air-bone gap,the air conduction hearing threshold,the dry ear rate,and the incidence of complications in both groups were compared before and after treatment.Results:The healing rate of the tympanic membrane in the patch group was significantly higher than that of the control group(95.75%vs.76.09%),with P<0.05;there was no difference in the air-bone gap and air conduction hearing threshold levels between the two groups before treatment(P>0.05),and the hearing indexes of the patch group were significantly lower than those of the control group 3 months after treatment(P<0.05);the dry ear rate in the patch group was significantly higher than that of the control group after treatment(85.11%vs.67.39%),and the total incidence of complications was also significantly lower than that of the control group(6.38%vs.21.74%),with P<0.05.Conclusion:The simple egg membrane patch bridging method is effective in repairing tympanic membrane perforation,which can effectively improve patients’hearing levels and reduce the occurrence of post-treatment complications.Thus,it is worth popularizing and applying in the clinic. 展开更多
关键词 Egg membrane patch bridging method Tympanic membrane perforation Hearing level
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利用GPS对磁暴期间极区TEC变化与极区碎片(Polar Patches)的研究 被引量:13
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作者 孟泱 王泽民 +1 位作者 鄂栋臣 蔡红涛 《地球物理学报》 SCIE EI CSCD 北大核心 2008年第1期17-24,共8页
利用2004年11月6-10日磁暴发生期间南极区域内的中国中山站GPS常年跟踪站(ZHON)和国际GPS服务站(CAS1,MCM4,SYOG,MAW1)的GPS观测数据,计算了可观测卫星传播路径上的TEC和ROT值,进而依据TEC的波动频率和幅度推估出极区碎片的个数,分... 利用2004年11月6-10日磁暴发生期间南极区域内的中国中山站GPS常年跟踪站(ZHON)和国际GPS服务站(CAS1,MCM4,SYOG,MAW1)的GPS观测数据,计算了可观测卫星传播路径上的TEC和ROT值,进而依据TEC的波动频率和幅度推估出极区碎片的个数,分析了极区磁暴期间电离层响应及其极区碎片特性.最终所得TEC和ROT结果与极区地磁场Dst和Kp指数信息相吻合,如实地反映了磁暴事件和极区碎片的出现.本文所做工作在国内尚未开展,因此所用方法和结论为将来这一方向的研究提供了一定的参考. 展开更多
关键词 磁暴 极区碎片(polar patches) GPS TEC ROT
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大鼠纹状体Patch和Matrix间区及其神经元形态学特征的观察 被引量:2
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作者 雷万龙 刘冰冰 +2 位作者 穆淑花 李可一 朱亚西 《中山大学学报(医学科学版)》 CAS CSCD 北大核心 2009年第2期121-125,136,共6页
【目的】纹状体Patch和Matrix间区被证实与神经精神活动和躯体运动有关。本实验旨在探测Patch和Matrix间区及其神经元的形态学特征,为研究纹状体-Patch和-Matrix神经元的通路联系提供资料。【方法】成年雄性SD大鼠分别按照常规和电镜要... 【目的】纹状体Patch和Matrix间区被证实与神经精神活动和躯体运动有关。本实验旨在探测Patch和Matrix间区及其神经元的形态学特征,为研究纹状体-Patch和-Matrix神经元的通路联系提供资料。【方法】成年雄性SD大鼠分别按照常规和电镜要求灌注固定、取脑和后固定;半导体或振动切片之后进行免疫组化PAP方法单标记和双标记;光镜下分别用Photoshop软件测量Patch和Matrix间区的面积并计算百分比;光镜和电镜下观察阳性神经元的结构;实验数据用SPSS软件统计处理。【结果】①Mor阳性的Patch间区呈不规则形的斑块状散在分布于纹状体,在胼胝体深方存在一条恒定的阳性带状区。Patch间区占纹状体面积的9%,其面积在纹状体的头侧明显大于尾侧(P<0.05)。阳性结构呈细丝或絮状,阳性胞体不明显。②Calb阳性的Matrix间区在纹状体内侧区染色较深,可见明显不规则的淡染色区,其形状与相邻片的Patch间区一致。Matrix间区的面积明显大于Patch间区(P<0.05)。可见阳性树突和树突棘,但阳性胞体不明显。③电镜下分别可见Mor和Calb阳性树突和树突棘,其大多数接受兴奋性突触连接,而与阳性树突形成的突触多为穿孔型。抑制性突触少见,阳性胞体不明显。【结论】头侧纹状体密集分布的Patch间区、内侧纹状体Calb强烈反应,和阳性标记的树突、树突棘以及兴奋性突触为主的形态学特征,提示Mor和Calb阳性神经元分别具有特异性的神经通路连接和生理机能。 展开更多
关键词 纹状体 patch间区 Matrix间区 MOR CALB
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patched基因在肝细胞癌中的表达及意义 被引量:1
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作者 刘云建 黄淑红 +3 位作者 陈连周 薛玲 张红卫 汪谦 《山东医药》 CAS 北大核心 2007年第6期13-14,共2页
目的探讨patched(Ptc)基因在肝细胞癌(HCC)中的表达及其临床意义。方法采用组织芯片技术和免疫组化(ABC-HRP)法对150例HCC手术切除标本进行Ptc检测,评估Ptc的表达与HCC临床病理的关系。结果150例肝癌组织,脱片9例,141例中39例有高表达(2... 目的探讨patched(Ptc)基因在肝细胞癌(HCC)中的表达及其临床意义。方法采用组织芯片技术和免疫组化(ABC-HRP)法对150例HCC手术切除标本进行Ptc检测,评估Ptc的表达与HCC临床病理的关系。结果150例肝癌组织,脱片9例,141例中39例有高表达(26.6%);25例癌旁肝组织无脱片,阳性表达3例(12.0%)。二者比较有显著性差异(P<0.05)。Ptc阳性表达与HCC的转移、淋巴浸润、包膜形成及细胞分化密切相关(P<0.05)。结论Ptc检测对估计HCC的转移、复发及预后具有意义。 展开更多
关键词 肝肿瘤 patchED 基因
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弓形虫复合粘膜疫苗滴鼻免疫小鼠诱导的Peyer's patches持续性细胞免疫应答 被引量:2
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作者 孟晓丽 殷国荣 +3 位作者 张建红 刘红丽 申金雁 李珀 《中国病原生物学杂志》 CSCD 2008年第1期27-30,共4页
目的以可溶性速殖子抗原(soluble tachyzoite antigen,STAg)和霍乱毒素(choleratoxin,CT)佐剂制备的弓形虫复合粘膜疫苗滴鼻免疫小鼠,观察肠粘膜诱导部位Peyer’s patches(PP)的细胞免疫应答及持续时间,探讨其免疫机制。方法B... 目的以可溶性速殖子抗原(soluble tachyzoite antigen,STAg)和霍乱毒素(choleratoxin,CT)佐剂制备的弓形虫复合粘膜疫苗滴鼻免疫小鼠,观察肠粘膜诱导部位Peyer’s patches(PP)的细胞免疫应答及持续时间,探讨其免疫机制。方法BALB/c小鼠96只,随机分为实验组和对照组,实验组以STAg(20μg/只)为抗原,CT(1/μg/只)为佐剂滴鼻免疫,对照组PBS滴鼻。滴鼻2次(间隔2周)后,每组6只小鼠分别于第1、2、3、4、6、8、10、12周处死。计数PP个数,制备PP淋巴细胞悬液,计数并涂片;免疫细胞化学法检测CD4^+、CD8^+T细胞亚群。结果实验期间两组小鼠PP数目均无明显变化;实验组免疫后PP淋巴细胞数量明显增生,第2周达高峰,第1、2、3周显著高于对照组(P〈0.05),其中以CD4^+T细胞增生为主,第1周~第8周高于对照组(P〈0.01),CD8^+T细胞第1周~第4周显著增高(P〈0.01),CD4^+/CD8^+比值无显著变化(P〉0.05)。结论弓形虫复合粘膜疫苗滴鼻免疫BALB/c小鼠可有效诱导肠PP部位持续性的免疫应答,从而激活肠粘膜效应部位淋巴细胞的抗弓形虫感染作用。 展开更多
关键词 弓形虫 粘膜疫苗 滴鼻免疫 可溶性速殖子抗原 霍乱毒素 Peyer’s patchES
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疝修复补片:材料设计与应用的最新进展
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作者 陈静宇 洪阁 +1 位作者 郭宁 刘天军 《中国组织工程研究》 CAS 北大核心 2025年第16期3494-3502,共9页
背景:与传统的缝合方式相比,采用补片修复腹壁缺陷的无张力疝修补手术能有效减少术后疼痛和疝气复发率,已经成为近年来治疗腹疝的首选方法。目的:归纳总结不同疝修复补片在应用过程中的优缺点。方法:以“腹壁缺损,疝气补片,疝气治疗”... 背景:与传统的缝合方式相比,采用补片修复腹壁缺陷的无张力疝修补手术能有效减少术后疼痛和疝气复发率,已经成为近年来治疗腹疝的首选方法。目的:归纳总结不同疝修复补片在应用过程中的优缺点。方法:以“腹壁缺损,疝气补片,疝气治疗”为中文检索词,以“abdominal wall defect,hernia patches,hernia treatment”为英文检索词,分别检索中国知网、谷歌学术和PubMed数据库,检索时限主要为2018年1月至2024年2月,同时采用少数经典的早期文献以概述疝修复补片的发展历程,通过阅读题目和摘要进行初步筛选,排除与疝修复材料相关性较低的文献,最终纳入90篇文献进行归纳总结。结果与结论:根据制备材料的不同可以将疝修复补片分为不可吸收人工合成补片、可吸收人工合成补片、天然高分子补片和复合补片。不可吸收补片具有较高的机械强度,有益于疝气区域的组织愈合,但体内长期存在的补片可能会引发身体的免疫反应,导致炎症和疼痛。可吸收人工合成补片与天然高分子补片具有良好的组织相容性、降解性,但机械强度不稳定。复合材料补片继承了传统不可吸收补片优良的机械性能,同时通过可吸收部分的设计降低了一些并发症发生的风险。在疝修复补片的后续研究中,科研人员应重点关注如何将新技术与复合补片结合起来,形成多功能的疝修复补片。 展开更多
关键词 腹壁缺损 疝修复补片 聚丙烯 抗菌补片 疝气 不可吸收补片 可吸收补片 复合补片
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基于声辐射模态的双面Patch近场声全息技术 被引量:2
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作者 郭亮 朱海潮 毛荣富 《海军工程大学学报》 CAS 北大核心 2015年第5期25-29,共5页
针对近场声全息技术在应用过程中遇到的外界干扰和测量孔径效应的双重问题,提出了基于源强密度声辐射模态理论的双面Patch近场声全息技术。经过理论分析和公式推导,建立了由声辐射模态叠加表达的声场声压数学模型。首先,采用双面声场分... 针对近场声全息技术在应用过程中遇到的外界干扰和测量孔径效应的双重问题,提出了基于源强密度声辐射模态理论的双面Patch近场声全息技术。经过理论分析和公式推导,建立了由声辐射模态叠加表达的声场声压数学模型。首先,采用双面声场分离技术清除测量面背向干扰源的影响;然后,对分离数据进行内插与外推,等效增加声源在全息面处的声压数据,减小了测量间隔;最后,获得了声源在非自由声场环境下具有高空间分辨率的全息图像。与传统的分离方法和Patch技术相比,所提方法综合考虑了相关参数的优化选择与控制,便于应用与推广。为了验证该方法,在理论工作的基础上,以刚性脉动球为对象进行了仿真研究,以音箱为对象进行了试验测试,相关结果证明了该方法的有效性与正确性。 展开更多
关键词 源强密度声辐射模态 双面声场分离 patch技术 近场声全息
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Patched基因在恶性肿瘤中的表达及其临床意义 被引量:2
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作者 蔡清河 涂海健 余加和 《医学综述》 2009年第4期520-522,共3页
Shh信号通道在胚胎发育过程中对细胞的生长、发育、增殖和分化意义重大,通道的异常会引起肿瘤的发生Patched基因是Shh信号通道中的一种肿瘤抑制基因。近年来的许多研究发现,Patched基因的异常表达与一些恶性肿瘤的发生发展密切相关,P... Shh信号通道在胚胎发育过程中对细胞的生长、发育、增殖和分化意义重大,通道的异常会引起肿瘤的发生Patched基因是Shh信号通道中的一种肿瘤抑制基因。近年来的许多研究发现,Patched基因的异常表达与一些恶性肿瘤的发生发展密切相关,Patched基因可以作为某些恶性肿瘤诊断和评价预后的指标,是某些恶性肿瘤生物治疗的靶标之一。本文就Patched基因在某些恶性肿瘤的表达及其临味意义予以综述。 展开更多
关键词 patched基因 SHH信号通路 恶性肿瘤
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