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Insights into left-right asymmetric development of chicken ovary at the single-cell level 被引量:1
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作者 Tao Wang Dong Leng +5 位作者 Zhongkun Cai Binlong Chen Jing Li Hua Kui Diyan Li Zhuanjian Li 《Journal of Genetics and Genomics》 SCIE CAS CSCD 2024年第11期1265-1277,共13页
Avian ovaries develop asymmetrically apart from prey birds,with only the left ovary growing more towards functional organ.Here,we analyze over 135,000 cells from chick's left and right ovaries at six distinct embr... Avian ovaries develop asymmetrically apart from prey birds,with only the left ovary growing more towards functional organ.Here,we analyze over 135,000 cells from chick's left and right ovaries at six distinct embryonic developmental stages utilizing single-cell transcriptome sequencing.We delineate gene expression patterns across 15 cell types within these embryo ovaries,revealing side-specific development.The left ovaries exhibit cortex cells,zygotene germ cells,and transcriptional changes unique to the left side.Differential gene expression analysis further identifies specific markers and pathways active in these cell types,highlighting the asymmetry in ovarian development.A fine-scale analysis of the germ cell meiotic transcriptome reveals seven distinct clusters with gene expression patterns specific to various meiotic stages.The study also identifies signaling pathways and intercellular communications,particularly between pre-granulosa and germ cells.Spatial transcriptome analysis shows the asymmetry,demonstrating cortex cells exclusively in the left ovary,modulating neighboring cell types through putative secreted signaling molecules.Overall,this single-cell analysis provides insights into the molecular mechanisms of the asymmetric development of avian ovaries,particularly the significant role of cortex cells in the left ovary. 展开更多
关键词 CHICKEN OVARY Asymmetric development left-right asymmetry Single-cell transcriptome Pre-granulosa Cellular crosstalk
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ccdc141 is required for left-right axis development by regulating cilia formation in the Kupffer's vesicle of zebrafish 被引量:1
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作者 Pengcheng Wang Wenxiang Shi +6 位作者 Sijie Liu Yunjing Shi Xuechao Jiang Fen Li Sun Chen Kun Sun Rang Xu 《Journal of Genetics and Genomics》 SCIE CAS CSCD 2024年第9期934-946,共13页
Laterality is a crucial physiological process intricately linked to the cilium-centrosome complex during embryo development.Defects in the process can result in severe organ mispositioning.Coiled-coil domain containin... Laterality is a crucial physiological process intricately linked to the cilium-centrosome complex during embryo development.Defects in the process can result in severe organ mispositioning.Coiled-coil domain containing 141(CCDC141)has been previously known as a centrosome-related gene,but its role in left-right(LR)asymmetry has not been characterized.In this study,we utilize the zebrafish model and human exome analysis to elucidate the function of ccdc141 in laterality defects.The knockdown of ccdc141 in zebrafish disrupts early LR signaling pathways,cilia function,and Kupffer's vesicle formation.Unlike ccdc141-knockdown embryos exhibiting aberrant LR patterns,ccdc141-null mutants show no apparent abnormality,suggesting a genetic compensation response effect.In parallel,we observe a marked reduction inα-tubulin acetylation levels in the ccdc141 crispants.The treatment with histone deacetylase(HDAC)inhibitors,particularly the HDAC6 inhibitor,rescues the ccdc141 crispant phenotypes.Furthermore,exome analysis of 70 patients with laterality defects reveals an increased burden of CCDC141 mutations,with in-vivo studies verifying the pathogenicity of the patient mutation CCDC141-R123G.Our findings highlight the critical role of ccdc141 in ciliogenesis and demonstrate that CCDC141 mutations lead to abnormal LR patterns,identifying it as a candidate gene for laterality defects. 展开更多
关键词 left-right axis CILIA WES Laterality defects ZEBRAFISH CCDC141
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Structure analysis of levitation chassis of medium-to-low speed maglev vehicles based on left-right decoupling 被引量:3
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作者 Fang LIU Jinwen DONG Yongzhi JING 《Journal of Modern Transportation》 2012年第2期82-87,共6页
Levitation chassis, as an extremely important component of maglev vehicles, provides functions of transmitting levitation force and steering force, and directly affects the safety performance of the vehicle. Based on ... Levitation chassis, as an extremely important component of maglev vehicles, provides functions of transmitting levitation force and steering force, and directly affects the safety performance of the vehicle. Based on the vertical dynamics model of the levitation chassis, kinetic equations of the model are established, and a simulation program is designed to analyze the structural decoupling function of the chassis, especially under the influence of elastic constraints between the left and right modules, which are exclusively owned by maglev vehicles. A finite element model of the levitation chassis based on left-right decoupling is constructed. Analysis results of the model show that the mechanical properties of the chassis tailored for the vehicle meet the design requirements, and the stiffness and strength is adequate to bear the weight of the whole vehicle. 展开更多
关键词 maglev vehicle levitation chassis DYNAMICS left-right decoupling finite element
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Sentiment Lexicon Construction Based on Improved Left-Right Entropy Algorithm 被引量:1
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作者 YU Shoujian WANG Baoying LU Ting 《Journal of Donghua University(English Edition)》 CAS 2022年第1期65-71,共7页
A novel method of constructing sentiment lexicon of new words(SLNW)is proposed to realize effective Weibo sentiment analysis by integrating existing lexicons of sentiments,lexicons of degree,negation and network.Based... A novel method of constructing sentiment lexicon of new words(SLNW)is proposed to realize effective Weibo sentiment analysis by integrating existing lexicons of sentiments,lexicons of degree,negation and network.Based on left-right entropy and mutual information(MI)neologism discovery algorithms,this new algorithm divides N-gram to obtain strings dynamically instead of relying on fixed sliding window when using Trie as data structure.The sentiment-oriented point mutual information(SO-PMI)algorithm with Laplacian smoothing is used to distinguish sentiment tendency of new words found in the data set to form SLNW by putting new words to basic sentiment lexicon.Experiments show that the sentiment analysis based on SLNW performs better than others.Precision,recall and F-measure are improved in both topic and non-topic Weibo data sets. 展开更多
关键词 sentiment lexicon new word discovery left-right entropy sentiment analysis point mutual information(PMI)
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Higgs and Single Top Associated Production at the LHC in the Left-Right Twin Higgs Model
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作者 蒋兴雨 韩金钟 +1 位作者 杨光 喻纯旭 《Communications in Theoretical Physics》 SCIE CAS CSCD 2017年第4期415-420,共6页
In the framework of the left-right twin Higgs(LRTH) model, we study the Higgs boson and single top quark associated production at the LHC. We investigate the processes pp → thj, pp → thˉb and pp → th W at the 8(14... In the framework of the left-right twin Higgs(LRTH) model, we study the Higgs boson and single top quark associated production at the LHC. We investigate the processes pp → thj, pp → thˉb and pp → th W at the 8(14) Te V LHC and find that the production cross sections of the three processes can be enhanced at different levels. Among them,the production cross section of the process pp → thˉb is enhanced significantly due to the contribution of the new particles predicted by the LRTH model. 展开更多
关键词 Higgs boson top quark left-right twin Higgs model
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Characteristics of Left-Right Spiral Hollow Cylindrical Roller
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作者 Liming Lu Qiping Chen Yujiang Qin 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2015年第2期74-78,共5页
Based on new rolling-sliding compound bearings,the wear between the one-way spiral hollow cylindrical roller and the ribs of the inner and outer ring of rolling-sliding compound bearings is reduced by innovational str... Based on new rolling-sliding compound bearings,the wear between the one-way spiral hollow cylindrical roller and the ribs of the inner and outer ring of rolling-sliding compound bearings is reduced by innovational structural design. A new left-right spiral hollow cylindrical roller is proposed to replace the one-way spiral hollow cylindrical roller. The finite element analysis models of ordinary cylindrical rollers,one-way spiral hollow cylindrical rollers and left-right spiral hollow cylindrical rollers are respectively established by ABAQUS.The axial displacement of their center mass and the stress distribution of left-right spiral hollow cylindrical rollers are compared and analyzed. Theoretical study results show that this new left-right spiral hollow cylindrical roller not only inherits the advantages of one-way spiral hollow cylindrical rollers,but also avoids the axial offset and the serious wear of the one-way spiral hollow cylindrical roller. And the theory research conclusion is verified by the experiment. The left-right spiral hollow cylindrical roller has the advantages to overcome boundary stress concentration like logarithmic convex roller. The rolling-sliding compound bearings equipped with the new rollers can be better to adapt to the impact of vibration load. 展开更多
关键词 left-right spiral hollow cylindrical roller finite element analysis DISPLACEMENT STRESS
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Single Production of Top Quark via e^-γ Collision in Left-Right Twin Higgs Model
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作者 LIU Yao-Bei WANG Xue-Lei +1 位作者 CAO Jun HAN Hong-Mei 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第8期445-450,共6页
In the context of the left-right twin Higgs (LRTH) model, we fist study single production of the standard model (SM) top quark via e-γ collisions. We find that the corrections of the LRTH model to the cross secti... In the context of the left-right twin Higgs (LRTH) model, we fist study single production of the standard model (SM) top quark via e-γ collisions. We find that the corrections of the LRTH model to the cross section of the process e-γ→vebt might be observed only for f ≤750 GeV and the heavy top quark mass scale M ≥500 GeV in future high energy linear e^+e^- collider (LC) experiment with the center-of-mass (CM) energy √s = 500 GeV and a yearly integrated luminosity of £ = 100 fb^-1. We also consider single production of the heavy top quark T via e-γ collisions. Our numerical results show that the possible signals of the heavy top quark T might be observed via the decay channel T →Ф^+b→tbb in future LC experiment with √s = 3 TeV and £ = 500 fb^-1. 展开更多
关键词 left-right twin Higgs model free parameter cross section
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Production of Charged Higgs Bosons from Left-Right Twin Higgs Model at TeV Energy e^-γ Colliders
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作者 申杰奋 刘要北 +1 位作者 赵晖 曹军 《Communications in Theoretical Physics》 SCIE CAS CSCD 2010年第10期701-708,共8页
The left-right twin Higgs (LRTH) model predicts the existence of three additional Higgs bosons: one neutral Higgs φo and a pair of charged Higgs bosons φ±. In this paper, we study two pair production process... The left-right twin Higgs (LRTH) model predicts the existence of three additional Higgs bosons: one neutral Higgs φo and a pair of charged Higgs bosons φ±. In this paper, we study two pair production processes of these new particles at the next generation eγ colliders, i.e., e-γ → e-φ+φ- , and e-γ→vRφ-φ0. We find that the production cross section of the process e-γ → e-φ+φ- are at the level of several tens fb, the production cross section of the process e-γ→vRφ-φ0 can reach 0.35 fb with the reasonable parameter values. As long as the charged Higgs bosons are not too heavy, we conclude that these processes might be used to test for the left-right twin Higgs model in future high-energy linear collider experiments. 展开更多
关键词 left-right twin Higgs model charged Higgs boson ILC
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Associated ZH and WH Production in Left-Right Twin Higgs Model at LHC
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作者 张艳菊 鲁公儒 《Communications in Theoretical Physics》 SCIE CAS CSCD 2011年第7期119-124,共6页
At the CERN large hadron collider (LHC), production of the Higgs boson in association with Z or W bosons provides a dramatic experimental signal for detecting the standard model (SM) Higgs boson. In this paper, we... At the CERN large hadron collider (LHC), production of the Higgs boson in association with Z or W bosons provides a dramatic experimental signal for detecting the standard model (SM) Higgs boson. In this paper, we consider the contributions of the left-right twin Higgs (LRTH) model to the processes qq' --~ Z(W)H. Our numerical results show that, in the favorable parameter spaces, the cross sections deviate distinctly from the predictions of the SM. The possible signals of the LRTH model can be detected via these processes at the LHC experiments. 展开更多
关键词 left-right twin Higgs model large hadron collider relation corrections
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Single Production of Charged Gauge Boson W_H^-from Left-Right Twin Higgs Model in Association with Top Quark at LHC
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作者 LIU Yao-Bei WANG Xue-Lei +1 位作者 HAN Hong-Mei CAO Yong-Hua 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第4期977-980,共4页
The twin Higgs mechanism has recently been proposed to solve the little hierarchy problem. In the context of the left-right twin Higgs (LRTH) model, we discuss single production of the new charged gauge boson WH^- ,... The twin Higgs mechanism has recently been proposed to solve the little hierarchy problem. In the context of the left-right twin Higgs (LRTH) model, we discuss single production of the new charged gauge boson WH^- , which is predicted by the left-right twin Higgs model, in association with top quark at the CERN Large Hadron Collider (LHC). It is found that, for a typical nonzero value of mass mixing parameter M = 150 GeV in the LRTH model, the production cross section is in the range of 3 ×10^-2 - 6.07×10^3 fb at the LHC. As long as the WH^- is not too heavy, the possible signatures of the heavy charged gauge boson might be detected at the LHC experiments. 展开更多
关键词 left-right twin Higgs model cross section new charged gauge boson
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Left-Right Non-Linear Dynamical Higgs
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作者 Jing Shu Juan Yepes 《Communications in Theoretical Physics》 SCIE CAS CSCD 2016年第12期643-662,共20页
All the possible CP-conserving non-linear operators up to the p^4-order in the Lagrangian expansion are analysed here for the left-right symmetric model in the non-linear electroweak chiral context coupled to a light ... All the possible CP-conserving non-linear operators up to the p^4-order in the Lagrangian expansion are analysed here for the left-right symmetric model in the non-linear electroweak chiral context coupled to a light dynamical Higgs. The low energy effects will be triggered by an emerging new physics field content in the nature, more specifically,from spin-1 resonances sourced by the straightforward extension of the SM local gauge symmetry to the larger local group SU(2)_L × SU(2)_R× U(1)_(B-L). Low energy phenomenology will be altered by integrating out the resonances from the physical spectrum, being manifested through induced corrections onto the left handed operators. Such modifications are weighted by powers of the scales ratio implied by the symmetries of the model and will determine the size of the effective operator basis to be used. The recently observed diboson excess around the invariant mass 1.8 TeV–2 TeV entails a scale suppression that suggests to encode the low energy effects via a much smaller set of effective operators. 展开更多
关键词 left-right model nonlinear invariance CP symmetry SU(2)×SU(2)×U(1) effective Lagrangian Higgs couplings
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LEFT-RIGHT BROWDER LINEAR RELATIONS AND RIESZ PERTURBATIONS 被引量:1
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作者 Teresa ALVAREZ 《Acta Mathematica Scientia》 SCIE CSCD 2017年第5期1437-1452,共16页
A closed linear relation T in a Banach space X is called left(resp. right) Fredholm if it is upper(resp. lower) semi Fredholm and its range(resp. null space) is topologically complemented in X. We say that T is left(r... A closed linear relation T in a Banach space X is called left(resp. right) Fredholm if it is upper(resp. lower) semi Fredholm and its range(resp. null space) is topologically complemented in X. We say that T is left(resp. right) Browder if it is left(resp. right)Fredholm and has a finite ascent(resp. descent). In this paper, we analyze the stability of the left(resp. right) Fredholm and the left(resp. right) Browder linear relations under commuting Riesz operator perturbations. Recent results of Zivkovic et al. to the case of bounded operators are covered. 展开更多
关键词 left and right Fredholm linear relations left and right Browder linear relations Riesz perturbations
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0νββdecay nuclear matrix elements under Left-Right symmetric model from the spherical quasi-particle random phase approximation method with realistic force
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作者 Ri-Guang Huang You-Cai Chen Dong-Liang Fang 《Chinese Physics C》 2026年第1期284-294,共11页
We perform the calculation of nuclear matrix elements for the neutrinoless double beta decays under a Left-Right symmetric model mediated by light neutrinos,and we adopt the spherical quasi-particle random-phase appro... We perform the calculation of nuclear matrix elements for the neutrinoless double beta decays under a Left-Right symmetric model mediated by light neutrinos,and we adopt the spherical quasi-particle random-phase approximation(QRPA)approach with a realistic force.For eight nuclei:^(76)Ge,^(82)Se,^(96)Zr,^(100)Mo,^(116)Cd,^(128)Te,^(130)Te,and^(136)Xe,related nuclear matrix elements are given.We analyze each term,and the details of contributions from different parts are also provided.For the q term,we find that the weak-magnetism components of the nucleon current contribute equally to other components such as the axial-vector.We also discuss the influence of short-range correlations on these NMEs.It is found that the R term is more sensitive to short-range correlations than other terms due to the large portion of the contribution from high exchange momenta. 展开更多
关键词 neutrinoless double beta decay nuclear matrix elements quasi-particle random-phase approximation left-right symmetric model
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Extra charged gauge boson W′in Alternative Left-Right Model at future muon collider
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作者 Liuxin Zhao Honglei Li +2 位作者 Zhi-Long Han Fei Huang Xinyi Yan 《Chinese Physics C》 2025年第12期27-38,共12页
The study of extra charged gauge bosons beyond the Standard Model has always been of great interest.Future muon colliders will have a significant advantage in discovering exotic particles.In this paper,by studying the... The study of extra charged gauge bosons beyond the Standard Model has always been of great interest.Future muon colliders will have a significant advantage in discovering exotic particles.In this paper,by studying theμ^(+)μ^(−)→W′^(+)W′^(−)→e^(+)e^(−)n_(e)n_(e)process,we explore the properties of W′in the alternative left-right model.The cross section and angular distribution of the final electron are investigated in a scenario of different W′masses and right-handed coupling constants.The forward-backward asymmetry is also an important observable to reflect the properties of W′.We provide a method to effectively suppress the background processes by imposing constraints on the transverse momentum PT and azimuthal angle of the final-state electronsα.With cuts of 600<P_(T)<3500 GeV and 0.5<α<3,the significance exceeds 5σfor 4.8 TeV W′at a collision energy of 10 TeV. 展开更多
关键词 new gauge boson muon collider alternative left-right model
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膜解剖理论指导食管裂孔疝手术的现状与未来:聚焦腹段食管精准游离
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作者 赵磊 张晓宁 +3 位作者 钟华 邓文兵 唐洪波 黄秋林 《中南医学科学杂志》 2026年第2期196-200,共5页
膜解剖理论基于组织胚胎发育视角,整合了传统“筋膜”“系膜”“间隙”“层面”“通道”等概念,该理论可延伸应用于食管裂孔疝的外科治疗。腹段食管游离层面不当可能损伤膈肌脚筋膜与肌纤维,影响缝合稳固性、增加复发风险,甚至导致食管... 膜解剖理论基于组织胚胎发育视角,整合了传统“筋膜”“系膜”“间隙”“层面”“通道”等概念,该理论可延伸应用于食管裂孔疝的外科治疗。腹段食管游离层面不当可能损伤膈肌脚筋膜与肌纤维,影响缝合稳固性、增加复发风险,甚至导致食管壁损伤、气胸或迷走神经损伤。因此,精确的层面控制是手术成功的重要保障。腹段食管游离主要涉及左右膈肌脚间隙的分离及纵隔内食管的解剖,其位于膈肌顶部的结构与盆底直肠具有相似性,手术理念可借鉴全直肠系膜切除术原则,力求在清晰解剖层面内完成整体游离。遵循膜解剖指导的手术既能确保解剖精准性、提高安全性,也有助于功能保护。随着人工智能技术带来的“认知增强”与机器人手术系统提供的“视觉与操作增强”深度融合,食管裂孔疝手术有望朝着更安全、更精准、更有效的方向进一步发展。 展开更多
关键词 膜解剖 食管裂孔疝 腹段食管游离 膈肌脚左右侧间隙 纵隔内食管
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左向右分流型先天性心脏病介入术后心脏超声指标变化的临床观察
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作者 张俊 潘莉 +1 位作者 王智 江楠 《中国医学创新》 2026年第8期149-154,共6页
目的:观察左向右分流型先天性心脏病(CHD)患儿接受介入治疗后心脏超声指标的变化。方法:回顾性选取2022年1月—2024年8月九江市妇幼保健院收治并行介入治疗的80例左向右分流型CHD患儿作为研究组,同期招募82例健康儿童作为对照组。采用... 目的:观察左向右分流型先天性心脏病(CHD)患儿接受介入治疗后心脏超声指标的变化。方法:回顾性选取2022年1月—2024年8月九江市妇幼保健院收治并行介入治疗的80例左向右分流型CHD患儿作为研究组,同期招募82例健康儿童作为对照组。采用经胸超声心动图检测两组心脏结构参数[左心室(LV)、右心房(RA)、右心室(RV)、左心房(LA)的内径,室间隔舒张期厚度(IVSd),左心室后壁厚度(LVPWd)],心室功能参数[左心室射血分数(LVEF)、舒张早期二尖瓣血流峰值速度(E)与舒张早期二尖瓣环峰值速度(e')的比值(E/e')],血流动力学参数[肺动脉流速、降主动脉流速、右心室收缩压(RVSP)、心输出量(CO)],瓣膜功能(二、三尖瓣反流面积)。基于对照组心脏超声指标,分析比较研究组患儿术后1、3、6个月时点的心脏超声各指标的变化。结果:术前研究组LA、RA、LV、RV内径和IVSd、LVPWd大于对照组,E/e'、肺动脉流速、降主动脉流速、RVSP高于对照组,二、三尖瓣反流面积大于对照组,LVEF、CO低于对照组(P<0.05)。研究组术后3、6个月LA、LV、RA、RV的内径及IVSd、LVPWd与对照组相比,差异有统计学意义(P<0.05);研究组术后1、3、6个月LVEF、E/e'、肺动脉流速、降主动脉流速、RVSP、CO、二尖瓣反流面积、三尖瓣反流面积与对照组比较,差异有统计学意义(P<0.05)。研究组术后1个月LVPWd与对照组比较,差异无统计学意义(P>0.05)。结论:左向右分流型CHD患儿在介入治疗后,心脏超声指标在术后6个月内呈现逐步改善趋势,包括心脏结构的逆向重塑,心室功能的增强、血流动力学的优化及瓣膜功能的恢复。但多数指标术后仍与正常水平有差异,LVPWd指标早期即接近正常。超声心动图作为一种重要的监测工具,可有效评估治疗效果。 展开更多
关键词 左向右分流型 先天性心脏病 介入治疗 心脏超声 术后评估
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预测伴右向左分流患者发生隐源性卒中的机器学习模型构建及可解释性分析
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作者 高小丽 唐素娟 +1 位作者 田菲菲 赵洪芹 《中国脑血管病杂志》 北大核心 2026年第2期75-86,共12页
目的构建预测伴右向左分流(RLS)患者发生隐源性卒中的最优机器学习模型,并进行可解释性分析。方法回顾性连续纳入2018年1月至2024年12月于青岛大学附属医院崂山院区神经内科因偏头痛、不明原因头晕、卒中等行对比增强经颅多普勒超声(c-T... 目的构建预测伴右向左分流(RLS)患者发生隐源性卒中的最优机器学习模型,并进行可解释性分析。方法回顾性连续纳入2018年1月至2024年12月于青岛大学附属医院崂山院区神经内科因偏头痛、不明原因头晕、卒中等行对比增强经颅多普勒超声(c-TCD)发泡试验并诊断存在RLS的患者。收集患者的一般资料及经胸超声心动图(TTE)检查的各项心脏参数,包括性别、年龄、吸烟史、饮酒史、高血压病、糖尿病、高脂血症、左心房直径(LAd)、左心房短径(LASd)、左心房长径(LALd)、左心室舒张末期内径(LVDd)、左心室收缩末期内径(LVDs)、左心室后壁厚度(LVPW)、室间隔厚度(IVS)、左心室射血分数(LVEF)及肺动脉收缩压(PASP)。根据是否发生隐源性卒中将所有患者分为隐源性卒中组和未发生卒中组,比较两组患者的一般资料及TTE各项心脏参数。基于所有患者的一般资料及TTE检查的各项心脏参数构建预测RLS患者发生隐源性卒中的Logistic回归、决策树、随机森林、极限梯度提升(XGBoost)、梯度提升和极限树6种机器模型。采用重复10次5折交叉验证评估6种机器学习模型的性能并分别绘制受试者工作特征(ROC)曲线,计算平均曲线下面积(AUC)、精确率、召回率、准确率和F1得分。绘制6种机器学习模型的校准曲线评估各模型的预测概率是否接近真实概率,采用决策曲线分析(DCA)评估6种机器学习模型预测RLS患者发生隐源性卒中不同阈值概率区间内可提供的净获益,以确定预测模型的临床价值,阈值范围0~<0.3为低风险区域,0.3~0.6为中等风险区域,>0.6~1.0为高风险区域。以重复10次5折交叉验证中性能最优者(以AUC值为首要指标,AUC相同时优选敏感度最高者)为最优机器学习模型,采用Delong检验比较最优机器学习模型与其他模型间AUC差异。将所有患者按照8∶2的比例随机分层抽样划分为训练集和测试集,基于训练集重新训练最优机器学习模型,并输入测试集中的数据进行Shapley加性解释(SHAP)分析。通过特征重要性柱状图(按平均SHAP值的降序排序)识别预测RLS患者发生隐源性卒中的核心预测因子;采用SHAP散点图分析特征值与模型输出的关联;采用SHAP Force图解析各特征预测单例RLS患者发生隐源性卒中的贡献度。绘制SHAP重要性排名前2位特征的部分依赖图,评估2个特征在RLS患者发生隐源性卒中预测中的边际效应及其非线性趋势,以探索最优机器学习模型量化关键预测因子与隐源性卒中发生风险的关系。结果共纳入310例RLS患者,男181例,女129例,年龄18~70岁,中位年龄52(43,52)岁,其中隐源性卒中组164例,未发生卒中组146例。(1)与未发生卒中组比较,隐源性卒中组患者年龄及男性、高血压病、糖尿病、高脂血症、吸烟史、饮酒史患者比例均更高,且LAd、LASd、LALd、LVDd、LVDs、LVPW、IVS和PASP均更大(均P<0.05);LVEF组间比较差异无统计学意义(P=0.306)。(2)采用重复10次5折交叉验证评估预测RLS患者发生隐源性卒中的6种机器学习模型的ROC,结果显示,极限树模型预测RLS患者发生隐源性卒中的平均AUC最高(0.804),其次为随机森林(0.792)、梯度提升(0.777)、XGBoost(0.776)、Logistic回归(0.764)和决策树(0.717)。(3)校准曲线显示,极限树模型的校准曲线(Brier分数为0.197)更加贴近参考线,其次为随机森林(Brier分数为0.210)、Logistic回归(Brier分数为0.222)、梯度提升(Brier分数为0.244)、决策树(Brier分数为0.263),XGBoost(Brier分数为0.280)最差。DCA显示,在部分中等风险区域(0.3~0.6),极限树模型的DCA曲线展现出较高的净获益率,在部分点表现明显优于其他模型。在高等风险区域(>0.6~1.0)净获益率下降,在低风险区域(0~<0.3)净获益率低且趋近不干预曲线,差异缩小。6种机器学习模型中极限树表现最佳,AUC为0.804,准确率为0.719、F1得分为0.736。Delong检验结果显示,极限树模型与决策树模型的AUC差异有统计学意义(P<0.05),与其他机器学习模型的差异均无统计学意义(均P>0.05)。(4)310例RLS患者中,训练集248例,测试集62例。与测试集比较,训练集RLS患者PASP更高(P=0.037),余训练集与测试集一般资料及TTE各项心脏参数的组间差异均无统计学意义(均P>0.05)。(5)基于训练集重新训练极限树模型,并输入测试集中的数据进行SHAP分析,结果显示,LAd对极限树模型的重要性最大,其次依次为LALd、年龄、LVPW、LVDs、高血压病、LVDd、吸烟史、PASP。SHAP散点图显示,可能增加了RLS患者发生隐源性卒中风险的特征排名前2位为LAd和LALd。(6)极限树模型的Force图显示,当SHAP值为1.0时,患者年龄为68岁,其LAd、LALd、LVDd、IVS、LVDs分别为34、56、48、10、30 mm。其中,LALd区域占比最大,LVEF区域占比最小。(7)基于极限树模型特征重要性前2位LAd与LALd生成RLS患者发生隐源性卒中的部分依赖图显示,LAd<32 mm时其平均预测概率为0.40,LAd为32~42 mm时的平均预测概率从0.35升至0.60,LAd>42 mm时的平均预测概率增长趋缓(平均预测概率为0.65);LALd<40 mm时平均预测概率稳定在0.40以下,LALd 40~55 mm时持续升至近0.60,LALd>55 mm后增长变缓。结论基于RLS患者一般及TTE心脏参数构建的极限树模型可较为准确地预测RLS患者发生隐源性卒中的风险,其中LAd和LALd是影响极限树模型输出的排名前2位的重要因素,该模型在外部队列中的有效性及其对隐源性卒中发生风险的预测价值转化潜力仍有待进一步明确。 展开更多
关键词 机器学习 右向左分流 隐源性卒中 预测模型
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人工智能软件在CT肺动脉造影诊断急性肺栓塞中的应用价值
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作者 黄文静 苏雪娟 +4 位作者 丁旭萌 李运奇 陈体 王力 边洪洁 《医学影像学杂志》 2026年第2期52-56,共5页
目的探讨人工智能(AI)软件在CT肺动脉造影(CTPA)诊断急性肺栓塞中的应用价值。方法选取行CTPA检查的疑似急性肺栓塞患者286例,以2位放射科副主任医师结合自主阅片及完整的临床资料进行复核的结果作为金标准。采用ROC曲线分析AI软件、放... 目的探讨人工智能(AI)软件在CT肺动脉造影(CTPA)诊断急性肺栓塞中的应用价值。方法选取行CTPA检查的疑似急性肺栓塞患者286例,以2位放射科副主任医师结合自主阅片及完整的临床资料进行复核的结果作为金标准。采用ROC曲线分析AI软件、放射科医师人工及两者联合对急性肺栓塞的诊断效能。对确诊急性肺栓塞患者,收集AI软件和放射科医师人工测量肺栓塞指数(PAOI)、右/左心室直径比(RV/LV)、肺/主动脉直径比(PA/AO)的结果,采用组内相关系数(ICC)分析AI软件与放射科医师人工测量结果的一致性,并采用Bland-Altman图展示。结果286例疑似患者中,确诊急性肺栓塞97例,排除急性肺栓塞189例。放射科医师联合AI软件诊断急性肺栓塞的AUC为0.979,优于AI软件、放射科医师人工单独诊断(AUC分别为0.901、0.956,P均<0.05)。AI软件与放射科医师测量的PAOI、RV/LV、PA/AO具有很高的一致性(ICC分别为0.921、0.908、0.846)。结论AI软件在CTPA诊断急性肺栓塞中具有一定应用价值,其辅助放射科医师能够明显提高对急性肺栓塞的诊断准确性。 展开更多
关键词 体层摄影术 X线计算机 人工智能 肺栓塞指数 右/左心室直径比 急性肺栓塞
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基于“左升右降”理论探讨放射性口腔黏膜炎的辨治思路
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作者 谭可欣 陈佳铭 +3 位作者 韩宸 陈坚 梁慧 谭英 《湖南中医杂志》 2026年第1期33-37,共5页
放射性口腔黏膜炎是严重影响头颈部肿瘤放疗患者生存质量及治疗进程的常见并发症,现代医学暂无特效治疗手段。中医学辨治多从“热毒伤阴”立论,但未系统阐述中焦脾胃及气机升降过程在该疾病中的重要性。文章以肺、肝、脾胃为代表的“左... 放射性口腔黏膜炎是严重影响头颈部肿瘤放疗患者生存质量及治疗进程的常见并发症,现代医学暂无特效治疗手段。中医学辨治多从“热毒伤阴”立论,但未系统阐述中焦脾胃及气机升降过程在该疾病中的重要性。文章以肺、肝、脾胃为代表的“左升右降”理论为切入点,系统剖析放射性口腔黏膜炎的深层病机并拓展其辨治思路。提出“中焦脾胃虚损为本,气机升降逆乱为标”的核心病机:放疗火热毒邪不仅直接灼伤阴津,更致脾胃虚弱;中轴失运,则肝气左升不及,影响情志疏泄,肺气右降无权,携热上逆,故见口咽燥渴,红肿热痛,终致气滞血瘀、黏膜失养溃烂。因此,治疗关键在于以健运脾胃、斡旋中焦为枢轴,辅以轻宣升散助肝气条达,肃降敛肺引火热下行。基于对古今验方与当代肿瘤名家辨治思路的梳理分析,该研究旨在构建一个以恢复“左升右降”为核心的中医辨治理论框架,从而为提升中医药防治放射性口腔黏膜炎的临床疗效提供理论参考。 展开更多
关键词 放射性口腔黏膜炎 左升右降 病因病机 辨治思路
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Muon-pair production in the left-right symmetric model at a Z^0-factory
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作者 MAHFOUDH A B 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2010年第11期1975-1980,共6页
The potential for probing the impacts of the left-right symmetric model (LRM) on the process e + e-→μ + μ-at a proposed Z 0-factory is investigated.Under different electron-positron polarization collision modes,we ... The potential for probing the impacts of the left-right symmetric model (LRM) on the process e + e-→μ + μ-at a proposed Z 0-factory is investigated.Under different electron-positron polarization collision modes,we calculate and compare the deviations of various observables in the framework of the LRM from the standard model (SM) predictions,such as the total cross section,the distribution of the transverse momentum of μ-,and the forward-backward charge asymmetry of μ-.In addition,we present the relations between the observables and the LRM parameters.We conclude that it is possible to observe the effects of the LRM on the process e + e-→μ + μ-by using optimal observables and favorable parameters at a Z 0-factory. 展开更多
关键词 Z 0 -factory electron-positron COLLIDER μ-pair production the left-right symmetric model
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