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Compact superconducting single-and dual-band filter design using multimode stepped-impedance resonator
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作者 王翔 魏斌 +2 位作者 陆喜龙 郭旭波 曹必松 《Chinese Physics B》 SCIE EI CAS CSCD 2017年第12期617-621,共5页
This study presents two multimode stepped-impedance structures to design single-and dual-band filters. Transmission zeroes are introduced for the single-band filter by using dual-mode stepped-impedance resonators. The... This study presents two multimode stepped-impedance structures to design single-and dual-band filters. Transmission zeroes are introduced for the single-band filter by using dual-mode stepped-impedance resonators. The single-band filter with high selectivity is centered at 6.02 GHz and has a fractional bandwidth (FBW) of 25.6%. Four stubs (two low frequency and two high frequency ones) are connected to the rectangular patch in the center to construct a quadruple-mode resonator. The independent conditions of the center frequencies of the high and low bands of the resonator are analyzed. A dual-band filter, which operates at 1.53 GHz and 2.44 GHz with FWBs of 12.1% and 14.1%, respectively is designed. The single-and dual-band filters are both fabricated with double-sided YBCO films and they can be used in mobile and satellite communications. 展开更多
关键词 high-temperature superconducting bandpass filter multimode stepped-impedance resonator dual-band filter
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Electrode design for multimode suppression of aluminum nitride tuning fork resonators
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作者 Yi Yuan Qingrui Yang +6 位作者 Haolin Li Shuai Shi Pengfei Niu Chongling Sun Bohua Liu Menglun Zhang Wei Pang 《Nanotechnology and Precision Engineering》 EI CAS CSCD 2023年第4期11-21,共11页
This paper is focused on electrode design for piezoelectric tuning fork resonators.The relationship between the performance and electrode pattern of aluminum nitride piezoelectric tuning fork resonators vibrating in t... This paper is focused on electrode design for piezoelectric tuning fork resonators.The relationship between the performance and electrode pattern of aluminum nitride piezoelectric tuning fork resonators vibrating in the in-plane flexural mode is investigated based on a set of resonators with different electrode lengths,widths,and ratios.Experimental and simulation results show that the electrode design impacts greatly the multimode effect induced from torsional modes but has little influence on other loss mechanisms.Optimizing the electrode design suppresses the torsional mode successfully,thereby increasing the ratio of impedance at parallel and series resonant frequencies(R_(p)/R_(s))by more than 80%and achieving a quality factor(Q)of 7753,an effective electromechanical coupling coefficient(kt_(eff)^(2))of 0.066%,and an impedance at series resonant frequency(R_(m))of 23.6 kΩ.The proposed approach shows great potential for high-performance piezoelectric resonators,which are likely to be fundamental building blocks for sensors with high sensitivity and low noise and power consumption. 展开更多
关键词 Tuning fork multimode AlN-based resonator Microelectromechanical systems
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Nomogram based on multimodal magnetic resonance combined with B7-H3mRNA for preoperative lymph node prediction in esophagus cancer
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作者 Yan-Han Xu Peng Lu +5 位作者 Ming-Cheng Gao Rui Wang Yang-Yang Li Rong-Qi Guo Wei-Song Zhang Jian-Xiang Song 《World Journal of Clinical Oncology》 2024年第3期419-433,共15页
Accurate preoperative prediction of lymph node metastasis(LNM)in esophageal cancer(EC)patients is of crucial clinical significance for treatment planning and prognosis.AIM To develop a clinical radiomics nomogram that... Accurate preoperative prediction of lymph node metastasis(LNM)in esophageal cancer(EC)patients is of crucial clinical significance for treatment planning and prognosis.AIM To develop a clinical radiomics nomogram that can predict the preoperative lymph node(LN)status in EC patients.METHODS A total of 32 EC patients confirmed by clinical pathology(who underwent surgical treatment)were included.Real-time fluorescent quantitative reverse transcription-polymerase chain reaction was used to detect the expression of B7-H3 mRNA in EC tissue obtained during preoperative gastroscopy,and its correlation with LNM was analyzed.Radiomics features were extracted from multi-modal magnetic resonance imaging of EC using Pyradiomics in Python.Feature extraction,data dimensionality reduction,and feature selection were performed using XGBoost model and leave-one-out cross-validation.Multivariable logistic regression analysis was used to establish the prediction model,which included radiomics features,LN status from computed tomography(CT)reports,and B7-H3 mRNA expression,represented by a radiomics nomogram.Receiver operating characteristic area under the curve(AUC)and decision curve analysis(DCA)were used to evaluate the predictive performance and clinical application value of the model.RESULTS The relative expression of B7-H3 mRNA in EC patients with LNM was higher than in those without metastasis,and the difference was statistically significant(P<0.05).The AUC value in the receiver operating characteristic(ROC)curve was 0.718(95%CI:0.528-0.907),with a sensitivity of 0.733 and specificity of 0.706,indicating good diagnostic performance.The individualized clinical prediction nomogram included radiomics features,LN status from CT reports,and B7-H3 mRNA expression.The ROC curve demonstrated good diagnostic value,with an AUC value of 0.765(95%CI:0.598-0.931),sensitivity of 0.800,and specificity of 0.706.DCA indicated the practical value of the radiomics nomogram in clinical practice.CONCLUSION This study developed a radiomics nomogram that includes radiomics features,LN status from CT reports,and B7-H3 mRNA expression,enabling convenient preoperative individualized prediction of LNM in EC patients. 展开更多
关键词 Esophageal cancer Radiomics B7-H3mRNA multimodal magnetic resonance imaging Lymph node metastasis NOMOGRAM
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COMPACT BANDPASS FILTER WITH HIGH SELECTIVITY AND WIDE STOPBAND USING SLOTTED STEPPED-IMPEDANCE RESONATOR
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作者 X11Jin JiYuxue MiaoChen WuWen 《Journal of Electronics(China)》 2012年第1期23-26,共4页
In this paper,a Slotted Stepped-Impedance Resonator (SSIR) is proposed.Due to the slots in the low-impedance section of the conventional SIR,the new resonator has a lower fundamental resonance f0 and can provide a pot... In this paper,a Slotted Stepped-Impedance Resonator (SSIR) is proposed.Due to the slots in the low-impedance section of the conventional SIR,the new resonator has a lower fundamental resonance f0 and can provide a potential finite transmission zero fz close to f0.Based on the proposed SSIR,a fourth-order Chebychev BandPass Filter (BPF) is designed at f0=1 GHz.The measured results show that a better than-65 dB rejection is achieved on both the lower and the upper stopband.Moreover,the new filter has a wide-30 dB rejection upper stopband from 1.13f0 to 6.52f0.The fabricated filter exhibits a size of The new filter has a planar topology and is easily integrated with modern portable communication systems. 展开更多
关键词 BandPass Filter (BPF) stepped-impedance resonator (SIR) High selectivity Wide stopband
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COMPACT INTERLOCKED-COUPLED FILTER USING FOLDED STEPPED-IMPEDANCE RESONATORS
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作者 Chen Chunhong Wu Wen Wu Hongmei 《Journal of Electronics(China)》 2012年第1期137-141,共5页
A microstrip interlocked-coupled bandpass filter is proposed with a markedly compact structure. The low-impedance open-end line of the quarter-wavelength Stepped-Impedance Resonator (SIR) is replaced by two open-end h... A microstrip interlocked-coupled bandpass filter is proposed with a markedly compact structure. The low-impedance open-end line of the quarter-wavelength Stepped-Impedance Resonator (SIR) is replaced by two open-end high-impedance lines, which not only facilitate the coupling mechanism but also provide the strong electric coupling between resonators. With the proper utilization of folded SIRs, the occupied area of coupled-resonator pair can be reduced. By applying the proposed coupled-resonator pair, the passband filter with the compact size can be realized. Good agreement between measured and simulated results is observed. The proposed filter is desirable for compact and high-performance microwave circuit applications. 展开更多
关键词 Microstrip filter Bandpass filter stepped-impedance resonator (SIR) Quarter-wavelength
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Multimodal imaging in the diagnosis of bone giant cell tumors:A retrospective study
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作者 Ming-Qing Kou Bing-Qiang Xu Hui-Tong Liu 《World Journal of Clinical Cases》 SCIE 2024年第16期2722-2728,共7页
BACKGROUND Giant cell tumor of bone is a locally aggressive and rarely metastasizing tumor,and also a potential malignant tumor that may develop into a primary malignant giant cell tumor.AIM To evaluate the role of mu... BACKGROUND Giant cell tumor of bone is a locally aggressive and rarely metastasizing tumor,and also a potential malignant tumor that may develop into a primary malignant giant cell tumor.AIM To evaluate the role of multimodal imaging in the diagnosis of giant cell tumors of bone.METHODS The data of 32 patients with giant cell tumor of bone confirmed by core-needle biopsy or surgical pathology at our hospital between March 2018 and March 2023 were retrospectively selected.All the patients with giant cell tumors of the bone were examined by X-ray,computed tomography(CT)and magnetic resonance imaging(MRI),and 7 of them were examined by positron emission tomography(PET)-CT.RESULTS X-ray imaging can provide overall information on giant cell tumor lesions.CT and MRI can reveal the characteristics of the internal structure of the tumor as well as the adjacent relationships of the tumor,and these methods have unique advantages for diagnosing tumors and determining the scope of surgery.PET-CT can detect small lesions and is highly valuable for identifying benign and malignant tumors to aid in the early diagnosis of metastasis.CONCLUSION Multimodal imaging plays an important role in the diagnosis of giant cell tumor of bone and can provide a reference for the treatment of giant cell tumors. 展开更多
关键词 Giant cell tumor of bone multimodal imaging Computed tomography Magnetic resonance imaging Positron emission tomography-computed tomography
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Multimodal morphometry and functional magnetic resonance imaging in schizophrenia and auditory hallucinations 被引量:3
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作者 Gracián García-Martí Eduardo Jesús Aguilar +2 位作者 Luis Martí-Bonmatí M José Escartí Julio Sanjuán 《World Journal of Radiology》 CAS 2012年第4期159-166,共8页
AIM: To validate a multimodal [structural and functional magnetic resonance (MR)] approach as coincidence brain clusters are hypothesized to correlate with clinical severity of auditory hallucinations. METHODS: Twenty... AIM: To validate a multimodal [structural and functional magnetic resonance (MR)] approach as coincidence brain clusters are hypothesized to correlate with clinical severity of auditory hallucinations. METHODS: Twenty-two patients meeting Diagnostic and Statistical Manual of Mental Disorders (fourth edition, DSM-IV) criteria for schizophrenia and experiencing persistent hallucinations together with 28 healthy controls were evaluated with structural and functional MR imaging with an auditory paradigm designed to replicate those emotions related to the patients’ hallucinatory experiences. Coincidence maps were obtained by combining structural maps of gray matter reduction with emotional functional increased activation. Abnormal areas were correlated with the brief psychiatric rating scale (BPRS) and the psychotic symptom rating scale (PSYRATS) scales. RESULTS: The coincidence analysis showed areas with coexistence gray matter reductions and emotional activation in bilateral middle temporal and superior temporal gyri. Significant negative correlations between BPRS and PSYRATS scales were observed. BPRS scores were negatively correlated in the middle temporal gyrus (right) (t = 6.86, P = 0.001), while negative PSYRATS correlation affected regions in both the superior temporal gyrus (left) (t = 7.85, P = 0.001) and middle temporal gyrus (left) (t = 4.97, P = 0.002). CONCLUSION: Our data identify left superior and middle temporal gyri as relevant areas for the understanding of auditory hallucinations in schizophrenia. The use of multimodal approaches, sharing structural and functional information, may demonstrate areas specifically linked to the severity of auditory hallucinations. 展开更多
关键词 FUNCTIONAL MORPHOMETRY Magnetic resonance SCHIZOPHRENIA Auditory hallucinations multimodAL COINCIDENCE
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Dual-polarized lens antenna based on multimode metasurfaces
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作者 Hao-Fang Wang Zheng-Bin Wang +1 位作者 Yong Cheng and Ye-Rong Zhang 《Chinese Physics B》 SCIE EI CAS CSCD 2018年第11期613-619,共7页
We propose a dual-polarized lens antenna system based on isotropic metasurfaces for 12 GHz applications. The metasurface lens is composed of subwavelength unit cells(0.24λ0) with metallic strips etched on the top a... We propose a dual-polarized lens antenna system based on isotropic metasurfaces for 12 GHz applications. The metasurface lens is composed of subwavelength unit cells(0.24λ0) with metallic strips etched on the top and bottom sides of the unit cell, and a cross-slots metallic layer in the middle that serves as the ground. The multimode resonance in the unit cell can realize a large phase shift(covering 0?–360?), and the total transmission efficiency of the lens is above 80%.The feed antenna at the focal point of the lens is a broadband dual-polarized microstrip antenna. Both the simulated and the measured results demonstrate that the dual-polarized lens antenna system can realize a gain of more than 16.1 dB, and an input port isolation of more than 25.0 dB. 展开更多
关键词 dual polarization metasurfaces lens antenna multimode resonance low-profile
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Brain Mechanisms of College Students’ Social Adjustment: Evidence from Multimodal Magnetic Resonance Imaging (MRI)
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作者 Ying Ge Weigang Pan Tin Wang 《Health》 2018年第4期442-457,共16页
This study investigated the neural basis of social adjustment using multimodal brain imaging and social-adjustment measurements to analyze functional and structural brain features during social adjustment in college s... This study investigated the neural basis of social adjustment using multimodal brain imaging and social-adjustment measurements to analyze functional and structural brain features during social adjustment in college students. The results showed that, regarding brain function, some dimensions of social adjustment were associated with the insula, and some regions of the frontal and occipital lobes. Self-adjustment and satisfaction required activation of the middle frontal gyrus, while career adjustment and academic adjustment required inhibition of the inferior frontal gyrus and lingual gyrus, respectively. Decreased metabolic activity of the lingual gyrus was beneficial for obtaining satisfaction. Regarding brain structure, the total score and some dimensions of social adaptation were associated with the gray matter of portions of the temporal and parietal lobes. The superior temporal gyrus was associated with the total social adjustment and satisfaction score, the middle temporal gyrus with campus-life adjustment and satisfaction, and the post central gyrus and the inferior parietal lobule with emotional adjustment. The changes in the gray matter volume of these brain regions to a certain extent reflected socially adaptive behaviors. The results suggest that social adaptability is associated with various brain regions dispersed among both hemispheres of the brain, and requires synergistic inter-actions between multiple brain regions and both brain hemispheres. 展开更多
关键词 Social Adjustment multimodAL NEUROIMAGING RESTING-STATE Functional Mag-netic resonANCE IMAGING Structural Magnetic resonANCE IMAGING
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Spatiotemporal mode-locked multimode fiber laser with dissipative four-wave mixing effect
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作者 Ming-Wei Qiu Chao-Qun Cai Zu-Xing Zhang 《Chinese Physics B》 SCIE EI CAS CSCD 2022年第10期165-170,共6页
The high degree of freedom and novel nonlinear phenomena of multimode fiber are attracting attention. In this work,we demonstrate a spatiotemporal mode-locked multimode fiber laser, which relies on microfiber knot res... The high degree of freedom and novel nonlinear phenomena of multimode fiber are attracting attention. In this work,we demonstrate a spatiotemporal mode-locked multimode fiber laser, which relies on microfiber knot resonance(MKR) via dissipative four-wave-mixing(DFMW) to achieve high-repetition-rate pulses. Apart from that, DFMW mode locking with switchable central wavelengths can also be obtained. It was further found that high pulse energy induced nonlinear effect of the dominant mode-locking mechanism transforming from DFMW to nonlinear Kerr beam cleaning effect(NL-KBC). The experimental results are valuable for further comprehending the dynamic characteristics of spatiotemporal mode-locked multimode fiber lasers, facilitating them much more accessible for applications. 展开更多
关键词 microfiber knot resonance(MKR) dissipative four-wave-mixing(DFMW) nonlinear Kerr beam cleaning effect(NL-KBC) multimode fiber laser
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Multimode Resonator Technique in Antennas:A 被引量:1
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作者 Lei Zhu Nengwu Liu 《Electromagnetic Science》 2023年第1期89-105,共17页
During the past several decades,the multimode resonator(MMR)technique has been extensively investigated and widely used,with successful exploration of a variety of high-performance patch antennas,slot antennas,dielect... During the past several decades,the multimode resonator(MMR)technique has been extensively investigated and widely used,with successful exploration of a variety of high-performance patch antennas,slot antennas,dielectric resonant antennas,dipole antennas,and so on.In this review paper,we summarize the research milestones for these MMR antennas worldwide as one of the most contributive research teams in this field.First,the basic working principles of the MMR technique are clearly illustrated and studied,including mode excitation,mode suppression,impedance performance improvement,and radiation performance improvement.Next,the research topics regarding impedance performance enhancement,i.e.,widebandwidth operation,multibandwidth operation,and mutual coupling reduction,based on the MMR method are intensively described.After that,the relevant works on radiation performance enhancement,i.e.,high-gain,wide-beamwidth,multibeam,multipolarization,low-cross-polarization,filtering-response,and leaky-wave antennas,based on the MMR method are extensively illustrated.By using this technique,several ideas about operating frequency reallocation,electric-field null control,radiation pattern reshaping,and efficiency null generation of the antennas are proposed and demonstrated by our team for the first time.In addition,the application of the MMR technique for wireless communication systems is introduced and presented,such as implant communication,wireless power transfer,and multiple-input multiple-output communication.With these arrangements,exploration and reporting of more interesting and useful MMR design methods can be anticipated in the future. 展开更多
关键词 ANTENNAS multimode resonator Impedance performance Radiation performance
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Advances in multimodal magnetic resonance imaging of vascular mild cognitive impairment
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作者 Zhi-Qi Wang Yan-Qing Han 《Journal of Hainan Medical University》 2019年第14期71-74,共4页
Vascular mild cognitive impairment(VaMCI)represents the early stage of symptoms of vascular cognitive impairment(VCI).There are many intervention factors in this period.If the active treatment can delay the further de... Vascular mild cognitive impairment(VaMCI)represents the early stage of symptoms of vascular cognitive impairment(VCI).There are many intervention factors in this period.If the active treatment can delay the further development of the disease and even reduce the risk of transforming into vascular dementia(VaD).As a widely used imaging method,multi-mode magnetic resonance imaging can evaluate the brain structure and function of patients with VaMCI noninvasively and explore the relationship between brain structure,function and cognitive function change.It is beneficial to provide an idea for early diagnosis of VaMCI and to further understand the neuropathologic mechanism of its occurrence,which has broad application prospects.In this paper,the research status and new methods of VaMCI are reviewed by using multi-mode magnetic resonance imaging in recent years. 展开更多
关键词 VASCULAR MILD COGNITIVE IMPAIRMENT multimodAL Magnetic resonance imaging Review
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Multimodal MRI diagnosis and transvenous embolization of a basicranial emissary vein dural arteriovenous fistula:A case report
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作者 Xi Chen Liang Ge +5 位作者 Hailin Wan Lei Huang Yeqing Jiang Gang Lu Jing Wang Xiaolong Zhang 《Journal of Interventional Medicine》 2023年第1期41-45,共5页
A dural arteriovenous fistula(DAVF) is an abnormal linkage connecting the arterial and venous systems within the intracranial dura mater. A basicranial emissary vein DAVF drains into the cavernous sinus and the ophtha... A dural arteriovenous fistula(DAVF) is an abnormal linkage connecting the arterial and venous systems within the intracranial dura mater. A basicranial emissary vein DAVF drains into the cavernous sinus and the ophthalmic vein, similar to a cavernous sinus DAVF. Precise preoperative identification of the DAVF location is a prerequisite for appropriate treatment. Treatment options include microsurgical disconnection, endovascular transarterial embolization(TAE), transvenous embolization(TVE), or a combination thereof. TVE is an increasingly popular approach for the treatment of DAVFs and the preferred approach for skull base locations, due to the risk of cranial neuropathy caused by dangerous anastomosis from arterial approaches. Multimodal magnetic resonance imaging(MRI) can provide anatomical and hemodynamic information for TVE. The therapeutic target must be precisely embolized in the emissary vein, which requires guidance via multimodal MRI. Here, we report a rare case of successful TVE for a basicranial emissary vein DAVF, utilizing multimodal MRI assistance. The fistula had vanished, pterygoid plexus drainage had improved, and the inferior petrosal sinus had recanalized, as observed on 8-month follow-up angiography. Symptoms and signs of double vision, caused by abduction deficiency, disappeared. Detailed anatomic and hemodynamic assessment by multimodal MRI is the key to guiding successful diagnosis and treatment. 展开更多
关键词 Dural arteriovenous fistula Transvenous embolization multimodal magnetic resonance imaging Cortical venous reflux ANGIOGRAPHY
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基于磁共振多模态成像定量参数鉴别诊断乳腺良恶性病变及与临床病理特征的关系探究 被引量:1
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作者 徐静 马光辉 +2 位作者 刘彭华 王勇刚 田志勇 《中国CT和MRI杂志》 2024年第3期93-96,共4页
目的 分析磁共振多模态成像定量参数鉴别诊断乳腺良恶性病变的价值,并探究乳腺病变性质与临床病理特征的关系。方法 纳入2015年1月-2022年12月医院120例乳腺占位性病变患者,所有患者入院时均接受磁共振多模态成像检查,包括弥散加权(DWI... 目的 分析磁共振多模态成像定量参数鉴别诊断乳腺良恶性病变的价值,并探究乳腺病变性质与临床病理特征的关系。方法 纳入2015年1月-2022年12月医院120例乳腺占位性病变患者,所有患者入院时均接受磁共振多模态成像检查,包括弥散加权(DWI)、磁共振波谱成像(MRS)与磁共振动态增强(DCE-MRI),以病理检查结果为“金标准”,分析该检查方式鉴别诊断乳腺良恶性病变的价值。依据乳腺占位性病变性质将患者分为恶性组与良性组,对比两组临床病理特征,分析乳腺病变性质与临床病理特征的关系。结果 120例乳腺占位性病变患者经病理检查结果显示,乳腺癌98例(81.67%),乳腺良性病变22例(18.33%);以病理检查结果为“金标准”,DCE-MRI及联合诊断乳腺病变性质的灵敏度、准确度高于DWI(P<0.05);乳腺癌组表观扩散系数(ADC)、rADC值低于乳腺良性病变组,Ⅰ型TIC曲线占比低于乳腺良性病变组,Ⅲ型TIC曲线占比高于乳腺良性病变组(P<0.05);绘制ROC曲线,结果显示,ADC、rADC及TIC曲线类型诊断乳腺病变性质具有一定价值(AUC=0.815、0.850、0.911);乳腺癌组肿瘤形态不规则、边缘毛刺/不规则、强化不均匀占比高于乳腺良性病变组(P<0.05);经Logistic回归分析,结果显示,肿瘤临床病理特征与乳腺占位性病变密切相关,形态不规则、边缘毛刺/不规则、强化不均匀是乳腺癌的危险因素(OR>1,P<0.05)。结论磁共振多模态成像定量参数对乳腺良恶性病变具有一定鉴别诊断价值,乳腺癌的发生与肿瘤形态不规则、边缘毛刺/不规则、强化不均匀等临床病理特征密切相关。 展开更多
关键词 乳腺良占位性病变 磁共振多模态成像 鉴别诊断 临床病理特征
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基于多模态MRI定量分析诊断宫颈癌宫旁浸润的研究 被引量:1
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作者 牛俊巧 王佳 +3 位作者 刘焱 曲源 张建亮 李辉 《中国CT和MRI杂志》 2024年第5期137-139,共3页
目的探讨多模态MRI定量分析诊断宫颈癌宫旁浸润的价值。方法回顾性分析2019年1月~2021年12月新疆维吾尔自治区人民医院收治的86例宫颈癌患者临床资料,根据病理结果分为宫旁浸润组31例与非宫旁浸润组55例。所有患者均接受MRI常规平扫及... 目的探讨多模态MRI定量分析诊断宫颈癌宫旁浸润的价值。方法回顾性分析2019年1月~2021年12月新疆维吾尔自治区人民医院收治的86例宫颈癌患者临床资料,根据病理结果分为宫旁浸润组31例与非宫旁浸润组55例。所有患者均接受MRI常规平扫及扩散加权成像(DWI)扫描、动态对比增强磁共振成像(DCE-MRI)扫描,获得感兴趣区表观弥散系数(ADC)值和对比剂容积转换常量(K^(trans))、速率常数(K_(ep))、血管外细胞间隙容积分数(V_(e))值等多模态MRI定量参数。比较宫旁浸润组和非宫旁浸润组临床特征、ADC值和DCE-MRI定量参数;Pearson相关性分析宫颈癌宫旁浸润患者ADC值和K^(trans)、K_(ep)、V_(e)的关系;受试者工作特征曲线(ROC)分析ADC值和K^(trans)、K_(ep)、V_(e)对宫颈癌宫旁浸润的诊断效能。结果宫旁浸润组与非宫旁浸润组肿瘤直径和病理分级的分布差异比较,差异有统计学意义(P<0.05);宫旁浸润组K^(trans)、K_(ep)和V_(e)均明显高于非宫旁浸润组(P<0.05);Pearson相关性显示,宫颈癌宫旁浸润患者ADC值与V_(e)值呈明显的正相关(P<0.05);ROC显示,K^(trans)、K_(ep)、V_(e)值诊断宫颈癌宫旁浸润的曲线下面积(AUC)分别为0.876、0.821和0.864(P<0.05)。结论多模态MRI定量参数对宫颈癌宫旁浸润具有较好的诊断价值,可为宫颈癌宫旁浸润的影像诊断提供量化参考。 展开更多
关键词 多模态MRI 扩散加权成像 动态对比增强磁共振成像 表观弥散系数 宫颈癌 宫旁浸润
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多模态磁共振成像评估乳腺癌腋窝淋巴结转移 被引量:1
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作者 徐静 马光辉 刘彭华 《中国医学装备》 2024年第5期64-68,共5页
目的:分析多模态磁共振成像(MRI)在乳腺癌腋窝淋巴结转移(ALNM)评估效果以及可靠指标。方法:选取2020年1月至2021年11月在邯郸市第一医院确诊并接受手术治疗的152例女性乳腺癌患者,根据术后腋窝淋巴结病理结果将其分为ALNM组(45例)和非A... 目的:分析多模态磁共振成像(MRI)在乳腺癌腋窝淋巴结转移(ALNM)评估效果以及可靠指标。方法:选取2020年1月至2021年11月在邯郸市第一医院确诊并接受手术治疗的152例女性乳腺癌患者,根据术后腋窝淋巴结病理结果将其分为ALNM组(45例)和非ALNM组(107例)。利用磁共振动态增强成像(DCE-MRI)、T2加权成像(T2WI)和弥散加权成像(DWI)技术对乳腺癌ALNM做出判定。结果:多模态MRI诊断灵敏度为82.22%,特异度为96.26%,阳性预测值为90.24%,阴性预测值为92.79%,诊断符合率为92.11%。logistic回归分析显示,肿瘤最大径、ADC值与淋巴结转移密切相关。受试者工作特征(ROC)曲线分析,肿瘤最大径ROC曲线下面积(AUC)为0.797(95%CI:0.694~0.842,P<0.01),在最佳截断值为1.96 cm下诊断的灵敏度为77.4%,特异度为60.7%;ADC值AUC为0.844(95%CI:0.808~0.915,P<0.01),在最佳截断值1.122×10^(-3)mm^(2)/s下诊断灵敏度为82.1%,特异度为71.2%。肿瘤最大径和AUC值联合诊断AUC为0.952(95%CI:0.904~0.991,P<0.01),最佳截断值下灵敏度为88.6%,特异度为81.4%。联合指标的AUC要高于肿瘤最大径(Z=3.982,P<0.05)和ADC值(Z=3.014,P<0.05)。结论:多模态MRI对乳腺癌ALNM诊断效果良好,其中肿瘤最大径和AUC值是重要的参考指标,两者联合应用能提高诊断效率。 展开更多
关键词 多模态磁共振成像(MRI) 乳腺癌 腋窝淋巴结转移(ALNM) 磁共振动态增强成像(DCE-MRI)
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多模态功能磁共振成像在乳腺癌诊断中的研究进展 被引量:1
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作者 张海青 邓之亚 徐虹 《海南医学》 CAS 2024年第8期1204-1208,共5页
乳腺癌(breast cancer)是女性发病率最高的恶性肿瘤,也是女性死亡率最高的恶性肿瘤之一。早发现、早诊断、早治疗不但能够延长患者生存率,同时可提高患者生活质量。磁共振成像是乳腺疾病成像的重要工具,目前已广泛应用于乳腺癌的鉴别、... 乳腺癌(breast cancer)是女性发病率最高的恶性肿瘤,也是女性死亡率最高的恶性肿瘤之一。早发现、早诊断、早治疗不但能够延长患者生存率,同时可提高患者生活质量。磁共振成像是乳腺疾病成像的重要工具,目前已广泛应用于乳腺癌的鉴别、诊断以及评估乳腺癌化疗反应。多模态功能磁共振成像不仅能够获得器官的血流动力学、水分子扩散及化合物代谢等信息,同时可反映肿瘤的进展和治疗相关的多种过程。本文论述了多模态、多参数磁共振成像在乳腺癌诊断中的应用进展及相关研究,以期在磁共振乳腺癌诊断中提供更多的诊疗信息,使更多患者在医疗中获益。 展开更多
关键词 乳腺癌 多模态磁共振成像 影像诊断 研究进展
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多模态影像技术在儿童症状性癫痫中的应用进展
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作者 房俊芳 狄宁宁 +3 位作者 董景敏 李潇潇 穆新暖 姜兴岳 《磁共振成像》 CAS CSCD 北大核心 2024年第4期171-176,共6页
儿童是癫痫的好发人群,由于其中枢神经系统处于发育阶段,所以病因更加复杂、表现形式更加多样,早期诊断和及时、有效处理能减少儿童中枢神经损伤,最大程度地保护患儿的脑功能。根据有无明显抽搐可将癫痫分为惊厥性和非惊厥性,而非惊厥... 儿童是癫痫的好发人群,由于其中枢神经系统处于发育阶段,所以病因更加复杂、表现形式更加多样,早期诊断和及时、有效处理能减少儿童中枢神经损伤,最大程度地保护患儿的脑功能。根据有无明显抽搐可将癫痫分为惊厥性和非惊厥性,而非惊厥性因无明显临床症状,诊断相对比较困难,容易导致误诊而延误治疗,明确诊断需要依靠脑电图(癫痫样或节律性放电)。随着影像检查手段的不断发展,明确癫痫病因、定位癫痫病灶的方式更加多样化,定位更加准确,同时功能成像检查方式也使得早期评估癫痫的脑功能变化成为可能。本文就近年来症状性儿童癫痫的MRI及其与正电子发射计算机断层显像(positron emission tomography,PET)融合应用的研究进展及临床应用进行综述,旨在为今后的相关研究提供参考和借鉴。 展开更多
关键词 儿童 癫痫 磁共振成像 结构磁共振成像 功能磁共振成像 多模态成像
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糖尿病周围神经病变多模态MRI研究进展
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作者 王丽芹 曹丹娜 +3 位作者 高兆虹 胡婧 高胜兰 李晓陵 《磁共振成像》 CAS CSCD 北大核心 2024年第1期211-216,共6页
糖尿病周围神经病变(diabetes peripheral neuropathy,DPN)是较常见的糖尿病慢性并发症,严重影响患者生活质量。DPN发病机制比较复杂,目前研究表明与神经病理性改变关系密切。近些年多模态MRI获得长足进展,MRI以软组织分辨率高、无创、... 糖尿病周围神经病变(diabetes peripheral neuropathy,DPN)是较常见的糖尿病慢性并发症,严重影响患者生活质量。DPN发病机制比较复杂,目前研究表明与神经病理性改变关系密切。近些年多模态MRI获得长足进展,MRI以软组织分辨率高、无创、无辐射等优点著称,成为探索DPN中枢神经及周围神经发病机制的重要方法。本文应用基于体素的形态学测量(voxel-based morphometry,VBM)、弥散张量成像(diffusion tensor imaging,DTI)、功能MRI(functional MRI,fMRI)等技术,对研究DPN脑结构、脑功能改变以及周围神经结构异常的文献进行综述,为临床早期诊断和制订精准治疗方案提供依据。 展开更多
关键词 糖尿病周围神经病变 磁共振成像 多模态 结构磁共振成像 功能磁共振成像 弥散张量成像 磁共振波谱成像 灌注加权成像
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宽阻带多陷波超宽带滤波器
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作者 侯明 徐开心 +2 位作者 李小珍 张杨 胡雨婷 《探测与控制学报》 CSCD 北大核心 2024年第5期43-49,共7页
为抑制其他无线窄带通信系统对超宽带系统的干扰,并提高超宽带滤波器的阻带抑制特性,提出一种拥有宽阻带和三陷波的超宽带滤波器。该滤波器采用传统多模谐振器加载阶梯开路谐振器与扇形谐振器的结构实现超宽带特性,其阻带宽度达到24.3 G... 为抑制其他无线窄带通信系统对超宽带系统的干扰,并提高超宽带滤波器的阻带抑制特性,提出一种拥有宽阻带和三陷波的超宽带滤波器。该滤波器采用传统多模谐振器加载阶梯开路谐振器与扇形谐振器的结构实现超宽带特性,其阻带宽度达到24.3 GHz;为引入三陷波,该滤波器采用了加载开路谐振器、耦合L型短路短截线以及非对称耦合结构;通过并联开路谐振器加载扇形谐振器的结构,优化了通带插入损耗。经过电磁仿真,该滤波器通带范围为4.1~10.6 GHz,相对带宽为93.4%,插入损耗小于1.3 dB,三处陷波分别位于5.1、6.28、8.1 GHz处,且陷波深度均大于25 dB,保证了超宽带系统的通信质量。 展开更多
关键词 超宽带滤波器 多模谐振器 三陷波 宽阻带
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