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Analysis of Imaging Characteristics and Dynamic Changes of 3 Cases of Severe Novel Coronavirus Pneumonia in Qinghai Province
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作者 Yingfang Yu Ruiyun Zhao +3 位作者 Changde Li Fuqiang Ma Lingyun Guo Yang Li 《Journal of Clinical and Nursing Research》 2024年第3期120-126,共7页
Objective:To analyze the characteristics,dynamic changes,and outcomes of the first imaging manifestations of 3 patients with severe COVID-19 in our hospital.Methods:Computed tomography(CT)findings of 3 patients with s... Objective:To analyze the characteristics,dynamic changes,and outcomes of the first imaging manifestations of 3 patients with severe COVID-19 in our hospital.Methods:Computed tomography(CT)findings of 3 patients with severe COVID-19 who tested positive by the nucleic acid test in our hospital were selected,mainly focusing on the morphology,distribution characteristics,and dynamic changes of the first CT findings.Results:3 patients with severe pneumonia were older,with one aged 80.The first chest CT examination for all 3 patients differed.Imaging showed a leafy distribution of consolidation,primarily affecting the lower lobes of both lungs and extending subpleurally.A grid-like pattern was observed,along with changes in the consolidation and air bronchogram.These changes had slower absorption,especially in patients with underlying diseases.Conclusion:CT manifestations of severe COVID-19 have specific characteristics and the analysis of their characteristics and dynamic changes provide valuable insights for clinical treatment. 展开更多
关键词 COVID-19 imaging CT findings dynamic changes
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Image super‐resolution via dynamic network 被引量:1
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作者 Chunwei Tian Xuanyu Zhang +2 位作者 Qi Zhang Mingming Yang Zhaojie Ju 《CAAI Transactions on Intelligence Technology》 SCIE EI 2024年第4期837-849,共13页
Convolutional neural networks depend on deep network architectures to extract accurate information for image super‐resolution.However,obtained information of these con-volutional neural networks cannot completely exp... Convolutional neural networks depend on deep network architectures to extract accurate information for image super‐resolution.However,obtained information of these con-volutional neural networks cannot completely express predicted high‐quality images for complex scenes.A dynamic network for image super‐resolution(DSRNet)is presented,which contains a residual enhancement block,wide enhancement block,feature refine-ment block and construction block.The residual enhancement block is composed of a residual enhanced architecture to facilitate hierarchical features for image super‐resolution.To enhance robustness of obtained super‐resolution model for complex scenes,a wide enhancement block achieves a dynamic architecture to learn more robust information to enhance applicability of an obtained super‐resolution model for varying scenes.To prevent interference of components in a wide enhancement block,a refine-ment block utilises a stacked architecture to accurately learn obtained features.Also,a residual learning operation is embedded in the refinement block to prevent long‐term dependency problem.Finally,a construction block is responsible for reconstructing high‐quality images.Designed heterogeneous architecture can not only facilitate richer structural information,but also be lightweight,which is suitable for mobile digital devices.Experimental results show that our method is more competitive in terms of performance,recovering time of image super‐resolution and complexity.The code of DSRNet can be obtained at https://github.com/hellloxiaotian/DSRNet. 展开更多
关键词 CNN dynamic network image super‐resolution lightweight network
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Image Hiding with High Robustness Based on Dynamic Region Attention in the Wavelet Domain
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作者 Zengxiang Li Yongchong Wu +3 位作者 Alanoud Al Mazroa Donghua Jiang Jianhua Wu Xishun Zhu 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第10期847-869,共23页
Hidden capacity,concealment,security,and robustness are essential indicators of hiding algorithms.Currently,hiding algorithms tend to focus on algorithmic capacity,concealment,and security but often overlook the robus... Hidden capacity,concealment,security,and robustness are essential indicators of hiding algorithms.Currently,hiding algorithms tend to focus on algorithmic capacity,concealment,and security but often overlook the robustness of the algorithms.In practical applications,the container can suffer from damage caused by noise,cropping,and other attacks during transmission,resulting in challenging or even impossible complete recovery of the secret image.An image hiding algorithm based on dynamic region attention in the multi-scale wavelet domain is proposed to address this issue and enhance the robustness of hiding algorithms.In this proposed algorithm,a secret image of size 256×256 is first decomposed using an eight-level Haar wavelet transform.The wavelet transform generates one coefficient in the approximation component and twenty-four detail bands,which are then embedded into the carrier image via a hiding network.During the recovery process,the container image is divided into four non-overlapping parts,each employed to reconstruct a low-resolution secret image.These lowresolution secret images are combined using densemodules to obtain a high-quality secret image.The experimental results showed that even under destructive attacks on the container image,the proposed algorithm is successful in recovering a high-quality secret image,indicating that the algorithm exhibits a high degree of robustness against various attacks.The proposed algorithm effectively addresses the robustness issue by incorporating both spatial and channel attention mechanisms in the multi-scale wavelet domain,making it suitable for practical applications.In conclusion,the image hiding algorithm introduced in this study offers significant improvements in robustness compared to existing algorithms.Its ability to recover high-quality secret images even in the presence of destructive attacksmakes it an attractive option for various applications.Further research and experimentation can explore the algorithm’s performance under different scenarios and expand its potential applications. 展开更多
关键词 image hiding ROBUSTNESS wavelet transform dynamic region attention
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Emotionally Resonant Branding: The Role of AI in Synthesising Dynamic Brand Images for Artists in the Music Industry
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作者 Kaveen Prabodhya Thivanka Liyanage Weliweriya Liyanage Himendra Balalle 《Open Journal of Applied Sciences》 2024年第9期2661-2678,共18页
Artificial Intelligence (AI) expands its recognition rapidly through the past few years in the context of generating content dynamically, remarkably challenging the human creativity. This study aims to evaluate the ef... Artificial Intelligence (AI) expands its recognition rapidly through the past few years in the context of generating content dynamically, remarkably challenging the human creativity. This study aims to evaluate the efficacy of AI in enhancing personal branding for musicians, particularly in crafting brand images based on emotions received from the artist’s music will improve the audience perceptions regarding the artist’s brand. Study used a quantitative approach for the research, gathering primary data from the survey of 191 people—music lovers, musicians and music producers. The survey focuses on preferences, perceptions, and behaviours related to music consumption and artist branding. The study results demonstrate the awareness and understanding of AI’s role in personal branding within the music industry. Also, results indicate that such an adaptive approach enhances audience perceptions of the artist and strengthens emotional connections. Furthermore, over 50% of the participants indicated a desire to attend live events where an artist’s brand image adapts dynamically to their emotions. The study focuses on novel approaches in personal branding based on the interaction of AI-driven emotional data. In contrast to traditional branding concepts, this study indicates that AI can suggest dynamic and emotionally resonant brand identities for artists. The real time audience response gives proper guidance for the decision-making. This study enriches the knowledge of AI’s applicability to branding processes in the context of the music industry and opens the possibilities for additional advancements in building emotionally appealing brand identities. 展开更多
关键词 Artificial Intelligence Emotional Branding Personal Branding Music Industry dynamic Brand image Audience Perception Machine Learning Real-Time Emotional Responses
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Discrimination of Metastatic from Non-metastatic Mesorectal Lymph Nodes in Rectal Cancer Using Quantitative Dynamic Contrast-Enhanced Magnetic Resonance Imaging 被引量:17
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作者 于小平 文露 +2 位作者 侯静 王晖 卢强 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2016年第4期594-600,共7页
Preoperative detection of lymph nodes(LNs) metastasis is always highly challenging for radiologists nowadays. The utility of quantitative dynamic contrast-enhanced magnetic resonance imaging(QDCE-MRI) in identifyi... Preoperative detection of lymph nodes(LNs) metastasis is always highly challenging for radiologists nowadays. The utility of quantitative dynamic contrast-enhanced magnetic resonance imaging(QDCE-MRI) in identifying LNs metastasis is not well understood. In the present study, 59 patients with histologically proven rectal carcinoma underwent preoperative QDCE-MRI. The short axis diameter ratio, long axis diameter ratio, short-to-long axis diameter ratio and QDEC-MRI parameters(Ktrans, Kep, fPV and Ve) values were compared between the non-metastatic(n=44) and metastatic(n=35) LNs groups based on pathological examination. Compared with the non-metastatic group, the metastatic group exhibited significantly higher short axis diameter(7.558±0.668 mm vs. 5.427±0.285 mm), Ktrans(0.483±0.198 min-1 vs. 0.218±0.116 min^-1) and Ve(0.399±0.118 vs. 0.203±0.096) values(all P〈0.05). The short-to-long axis diameter ratio, long axis diameter ratio, Kep and fPV values did not show significant differences between the two groups. In conclusion, our results showed that for LNs larger than 5 mm in rectal cancer, there are distinctive differences in the Ktrans and Ve values between the metastatic and non-metastatic LNs, suggesting that QDCE-MRI may be potentially helpful in identifying LNs status. 展开更多
关键词 rectal cancer lymph node dynamic contrast-enhanced magnetic resonance imaging quantitative analysis sensitivity and specificity
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Four-dimensional flow magnetic resonance imaging incirrhosis 被引量:7
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作者 Zoran Stankovic 《World Journal of Gastroenterology》 SCIE CAS 2016年第1期89-102,共14页
Since its introduction in the 1970’s,magnetic resonance imaging(MRI)has become a standard imaging modality.With its broad and standardized application,it is firmly established in the clinical routine and an essential... Since its introduction in the 1970’s,magnetic resonance imaging(MRI)has become a standard imaging modality.With its broad and standardized application,it is firmly established in the clinical routine and an essential element in cardiovascular and abdominal imaging.In addition to sonography and computer tomography,MRI is a valuable tool for diagnosing cardiovascular and abdominal diseases,for determining disease severity,and for assessing therapeutic success.MRI techniques have improved over the last few decades,revealing not just morphologic information,but functional information about perfusion,diffusion and hemodynamics as well.Four-dimensional(4D)flow MRI,a time-resolved phase contrast-MRI with three-dimensional(3D)anatomic coverage and velocity encoding along all three flow directions has been used to comprehensively assess complex cardiovascular hemodynamics in multiple regions of the body.The technique enables visualization of 3D blood flow patterns and retrospective quantification of blood flow parameters in a region of interest.Over the last few years,4D flow MRI has been increasingly performed in the abdominal region.By applying different acceleration techniques,taking 4D flow MRI measurements has dropped to a reasonable scanning time of 8 to 12 min.These new developments have encouraged a growing number of patient studies in the literature validating the technique’s potential for enhanced evaluation of blood flow parameters within the liver’s complex vascular system.The purpose of this review article is to broaden our understanding of 4D flow MRI for the assessment of liver hemodynamics by providing insights into acquisition,data analysis,visualization and quantification.Furthermore,in this article we highlight its development,focussing on the clinical application of the technique. 展开更多
关键词 four-dimensional FLOW MAGNETIC resonanceimaging Phase contrast-magnetic resonance imaging Liver CIRRHOSIS imaging technique HEMOdynamicS Bloodflow Visualization Quantification TIPS SPLANCHNIC system
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Texture analysis on parametric maps derived from dynamic contrast-enhanced magnetic resonance imaging in head and neck cancer 被引量:6
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作者 Jacobus FA Jansen Yonggang Lu +5 位作者 Gaorav Gupta Nancy Y Lee Hilda E Stambuk Yousef Mazaheri Joseph O Deasy Amita Shukla-Dave 《World Journal of Radiology》 CAS 2016年第1期90-97,共8页
AIM: To investigate the merits of texture analysis on parametric maps derived from pharmacokinetic modeling with dynamic contrast-enhanced magnetic resonance imaging(DCE-MRI) as imaging biomarkers for the prediction o... AIM: To investigate the merits of texture analysis on parametric maps derived from pharmacokinetic modeling with dynamic contrast-enhanced magnetic resonance imaging(DCE-MRI) as imaging biomarkers for the prediction of treatment response in patients with head and neck squamous cell carcinoma(HNSCC). METHODS: In this retrospective study,19 HNSCC patients underwent pre- and intra-treatment DCEMRI scans at a 1.5T MRI scanner. All patients had chemo-radiation treatment. Pharmacokinetic modeling was performed on the acquired DCE-MRI images,generating maps of volume transfer rate(Ktrans) and volume fraction of the extravascular extracellular space(ve). Image texture analysis was then employed on maps of Ktrans and ve,generating two texture measures: Energy(E) and homogeneity.RESULTS: No significant changes were found for the mean and standard deviation for Ktrans and ve between pre- and intra-treatment(P > 0.09). Texture analysis revealed that the imaging biomarker E of ve was significantly higher in intra-treatment scans,relative to pretreatment scans(P < 0.04). CONCLUSION: Chemo-radiation treatment in HNSCC significantly reduces the heterogeneity of tumors. 展开更多
关键词 Tumor HETEROGENEITY dynamic contrastenhanced magnetic resonance imaging image texture analysis Head and NECK SQUAMOUS cell CARCINOMAS
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Dual-input two-compartment pharmacokinetic model of dynamic contrast-enhanced magnetic resonance imaging in hepatocellular carcinoma 被引量:4
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作者 Jian-Feng Yang Zhen-Hua Zhao +6 位作者 Yu Zhang Li Zhao Li-Ming Yang Min-Ming Zhang Bo-Yin Wang Ting Wang Bao-Chun Lu 《World Journal of Gastroenterology》 SCIE CAS 2016年第13期3652-3662,共11页
AIM: To investigate the feasibility of a dual-input two-compartment tracer kinetic model for evaluating tumorous microvascular properties in advanced hepatocellular carcinoma(HCC). METHODS: From January 2014 to April ... AIM: To investigate the feasibility of a dual-input two-compartment tracer kinetic model for evaluating tumorous microvascular properties in advanced hepatocellular carcinoma(HCC). METHODS: From January 2014 to April 2015, we prospectively measured and analyzed pharmacokinetic parameters [transfer constant(K_(trans)), plasma flow(F_p), permeability surface area product(PS), efflux rate constant(k_(ep)), extravascular extracellular space volume ratio(V_e), blood plasma volume ratio(V_p), and hepatic perfusion index(HPI)] using dual-input two-compartment tracer kinetic models [a dual-input extended Tofts model and a dual-input 2-compartment exchange model(2CXM)] in 28 consecutive HCC patients. A well-known consensus that HCC is a hypervascular tumor supplied by the hepatic artery and the portal vein was used as a reference standard. A paired Student's t-test and a nonparametric paired Wilcoxon rank sum test were used to compare the equivalent pharmacokinetic parameters derived from the two models, and Pearson correlation analysis was also applied to observe the correlations among all equivalent parameters. The tumor size and pharmacokinetic parameters were tested by Pearson correlation analysis, while correlations among stage, tumor size and all pharmacokinetic parameters were assessed by Spearman correlation analysis. RESULTS: The F_p value was greater than the PS value(F_P = 1.07 m L/m L per minute, PS = 0.19 m L/m L per minute) in the dual-input 2CXM; HPI was 0.66 and 0.63 in the dual-input extended Tofts model and the dualinput 2CXM, respectively. There were no significant differences in the K_(ep), V_p, or HPI between the dual-input extended Tofts model and the dual-input 2CXM(P = 0.524, 0.569, and 0.622, respectively). All equivalent pharmacokinetic parameters, except for V_e, were correlated in the two dual-input two-compartment pharmacokinetic models; both Fp and PS in the dualinput 2CXM were correlated with K_(trans) derived from the dual-input extended Tofts model(P = 0.002, r = 0.566; P = 0.002, r = 0.570); K_(ep), V_p, and HPI between the two kinetic models were positively correlated(P = 0.001, r = 0.594; P = 0.0001, r = 0.686; P = 0.04, r = 0.391, respectively). In the dual input extended Tofts model, V_e was significantly less than that in the dual input 2CXM(P = 0.004), and no significant correlation was seen between the two tracer kinetic models(P = 0.156, r = 0.276). Neither tumor size nor tumor stage was significantly correlated with any of the pharmacokinetic parameters obtained from the two models(P > 0.05).CONCLUSION: A dual-input two-compartment pharmacokinetic model(a dual-input extended Tofts model and a dual-input 2CXM) can be used in assessing the microvascular physiopathological properties before the treatment of advanced HCC. The dual-input extended Tofts model may be more stable in measuring the V_e; however, the dual-input 2CXM may be more detailed and accurate in measuring microvascular permeability. 展开更多
关键词 HEPATOCELLULAR CARCINOMA dynamic contrastenhanced magnetic resonance imaging PHARMACOKINETICS
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Dynamic contrast-enhanced MR imaging findings of bone metastasis in patients with prostate cancer 被引量:5
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作者 Arda Kayhan Cheng Yang +5 位作者 Fatma Nur Soylu Hatice Lakadamyal Ila Sethi Gregory Karczmar Walter Stadler Aytekin Oto 《World Journal of Radiology》 CAS 2011年第10期241-245,共5页
AIM:To evaluate the dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) findings of bone metastasis in prostate cancer patients.METHODS:Sixteen men with a diagnosis of metastatic prostate cancer to bones we... AIM:To evaluate the dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) findings of bone metastasis in prostate cancer patients.METHODS:Sixteen men with a diagnosis of metastatic prostate cancer to bones were examined with DCE-MRI at 1.5 Tesla.The mean contrast agent concentration vs time curves for bone metastasis and normal bone were calculated and K trans and ve values were estimated and compared.RESULTS:An early significant enhancement (wash-out:n=6,plateau:n=8 and persistent:n=2) was detected in all bone metastases (n=16).Bone metastasis from prostate cancer showed significant enhancementand high K trans and ve values compared to normal bone which does not enhance in the elderly population.The mean K trans was 0.101/mmiinn and 0.0051/mmiinn (P < 0.001),the mean ve was 0.141 and 0.0038 (P < 0.001),for bone metastases and normal bone,respectively. 展开更多
关键词 PROSTATE Cancer BONE METASTASIS dynamic CONTRAST-ENHANCED MR imaging
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Photodissociation Dynamics of Carbon Dioxide Cation via the Vibrationally Mediated A^2Hu,1/2 State: A Time-Sliced Velocity-Mapped Ion Imaging Study
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作者 茆锐 何超 +3 位作者 陈旻 周丹娜 张群 陈旸 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2017年第2期123-127,I0001,共6页
We report on the photodissociation dynamics of CO2^+ via its A2Пu,1/2 state using the scheme of [1+1] photon excitation that is intermediated by the mode-selected A2Hu,1/2(Vl,V2,0) vibronic states. Photodissociat... We report on the photodissociation dynamics of CO2^+ via its A2Пu,1/2 state using the scheme of [1+1] photon excitation that is intermediated by the mode-selected A2Hu,1/2(Vl,V2,0) vibronic states. Photodissociation fragment exciation spectrum and images of photofragment CO+ have been measured to obtain reaction dynamics parameters such as the available energy and the average translational energy. Combining with the potential energy functions of CO2^+, the dissociation mechanism of CO2^+ is discussed. The conformational variation of CO2^+ from linear to bent on the photodissociation dynamics of CO2^+ is verified. 展开更多
关键词 Photodissociation dynamics Velocity map imaging Carbon dioxide cation
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Evaluation of Airway Obstruction at Soft Palate Level in Male Patients with Obstructive Sleep Apnea/Hypopnea Syndrome:Dynamic 3-Dimensional CT Imaging of Upper Airway 被引量:10
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作者 肖英 陈雄 +4 位作者 史河水 杨阳 何烈纯 董家琪 孔维佳 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2011年第3期413-418,共6页
This study examined the dynamic characteristics of upper airway collapse at soft palate level in patients with obstructive sleep apnea/hypopnea syndrome(OSAHS) by using dynamic 3-Dimensional(3-D) CT imaging.A tota... This study examined the dynamic characteristics of upper airway collapse at soft palate level in patients with obstructive sleep apnea/hypopnea syndrome(OSAHS) by using dynamic 3-Dimensional(3-D) CT imaging.A total of 41 male patients who presented with 2 of the following symptoms,i.e.,daytime sleepiness and fatigue,frequent snoring,and apnea with witness,were diagnosed as having OSAHS.They underwent full-night polysomnography and then dynamic 3-D CT imaging of the upper airway during quiet breathing and in Muller's maneuver.The soft palate length(SPL),the minimal cross-sectional area of the retropalatal region(mXSA-RP),and the vertical distance from the hard palate to the upper posterior part of the hyoid(hhL) were compared between the two breathing states.These parameters,together with hard palate length(HPL),were also compared between mild/moderate and severe OSAHS groups.Association of these parameters with the severity of OSAHS [as reflected by apnea hypopnea index(AHI) and the lowest saturation of blood oxygen(LSaO2)] was examined.The results showed that 31 patients had severe OSAHS,and 10 mild/moderate OSAHS.All the patients had airway obstruction at soft palate level.mXSA-RP was significantly decreased and SPL remarkably increased during Muller's maneuver as compared with the quiet breathing state.There were no significant differences in these airway parameters(except the position of the hyoid bone) between severe and mild/moderate OSAHS groups.And no significant correlation between these airway parameters and the severity of OSAHS was found.The position of hyoid was lower in the severe OSAHS group than in the mild/moderate OSAHS group.The patients in group with body mass index(BMI)≥26 had higher collapse ratio of mXSA-RP,greater neck circumference and smaller mXSA-RP in the Muller's maneuver than those in group with BMI26(P0.05 for all).It was concluded that dynamic 3-D CT imaging could dynamically show the upper airway changes at soft palate level in OSAHS patients.All the OSAHS patients had airway obstruction of various degrees at soft palate level.But no correlation was observed between the airway change at soft palate level and the severity of OSAHS.The patients in group with BMI≥26 were more likely to develop airway obstruction at soft palate level than those with BMI26. 展开更多
关键词 obstructive sleep apnea/hypopnea syndrome upper airway obstruction soft palate level dynamic computed tomography 3-Dimensional imaging
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Dynamic contrast-enhanced magnetic resonance imaging of prostate cancer: A review of current methods and applications 被引量:8
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作者 Yousef Mazaheri Oguz Akin Hedvig Hricak 《World Journal of Radiology》 CAS 2017年第12期416-425,共10页
In many areas of oncology, dynamic contrast-enhanced magnetic resonance imaging(DCE-MRI) has proven to be a clinically useful, non-invasive functional imaging technique to quantify tumor vasculature and tumor perfusio... In many areas of oncology, dynamic contrast-enhanced magnetic resonance imaging(DCE-MRI) has proven to be a clinically useful, non-invasive functional imaging technique to quantify tumor vasculature and tumor perfusion characteristics. Tumor angiogenesis is an essential process for tumor growth, proliferation, and metastasis. Malignant lesions demonstrate rapid extravasation of contrast from the intravascular space to the capillary bed due to leaky capillaries associated with tumor neovascularity. DCE-MRI has the potential to provide information regarding blood flow, areas of hypoperfusion, and variations in endothelial permeability and microvessel density to aid treatment selection, enable frequent monitoring during treatment and assess response to targeted therapy following treatment. This review will discuss the current status of DCE-MRI in cancer imaging, with a focus on its use in imaging prostate malignancies as well as weaknesses that limit its widespread clinical use. The latest techniques for quantification of DCE-MRI parameters will be reviewed and compared. 展开更多
关键词 Prostate cancer Prostate magnetic resonance imaging Tumor angiogenesis dynamic contrast-enhanced magnetic resonance imaging Kep = rate constant between extracellular extravascular space and plasma space Ktrans = volume transfer constant
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Pancreatic carcinoma coexisting with chronic pancreatitis versus tumor-forming pancreatitis:Diagnostic utility of the time-signal intensity curve from dynamic contrast-enhanced MR imaging 被引量:29
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作者 Yoshitsugu Tajima Tamotsu Kuroki +3 位作者 Ryuji Tsutsumi Ichiro Isomoto Masataka Uetani Takashi Kanematsu 《World Journal of Gastroenterology》 SCIE CAS CSCD 2007年第6期858-865,共8页
AIM: To evaluate the ability of the time-signal intensity curve (TIC) of the pancreas obtained from dynamic contrast-enhanced magnetic resonance imaging (MRI) for differentiation of focal pancreatic masses, especially... AIM: To evaluate the ability of the time-signal intensity curve (TIC) of the pancreas obtained from dynamic contrast-enhanced magnetic resonance imaging (MRI) for differentiation of focal pancreatic masses, especially pancreatic carcinoma coexisting with chronic pancreatitis and tumor-forming pancreatitis. METHODS: Forty-eight consecutive patients who underwent surgery for a focal pancreatic mass, including pancreatic ductal carcinoma (n = 33), tumor-forming pancreatitis (n = 8), and islet cell tumor (n = 7), were reviewed. Five pancreatic carcinomas coexisted with longstanding chronic pancreatitis. The pancreatic TICs were obtained from the pancreatic mass and the pancreatic parenchyma both proximal and distal to the mass lesion in each patient, prior to surgery, and were classified into 4 types according to the time to a peak: 25 s and 1, 2, and 3 min after the bolus injection of contrast material, namely, type-Ⅰ, Ⅱ, Ⅲ, and Ⅳ, respectively, and were then compared to the corresponding histological pancreatic conditions. RESULTS: Pancreatic carcinomas demonstrated type-Ⅲ (n = 13) or Ⅳ (n = 20) TIC. Tumor-forming pancreatitis showed type-Ⅱ (n = 5) or Ⅲ (n = 3) TIC. All islet cell tumors revealed type-Ⅰ. The type-Ⅳ TIC was only recognized in pancreatic carcinoma, and the TIC of carcinoma always depicted the slowest rise to a peak among the 3 pancreatic TICs measured in each patient, even in patients with chronic pancreatitis.CONCLUSION: Pancreatic TIC from dynamic MRI provides reliable information for distinguishing pancreatic carcinoma from other pancreatic masses, and may enable us to avoid unnecessary pancreatic surgery and delays in making a correct diagnosis of pancreatic carcinoma, especially, in patients with longstanding chronic pancreatitis. 展开更多
关键词 Pancreatic carcinoma Chronic pancreatitis Focal pancreatic mass Tumor-forming pancreatitis Differential diagnosis dynamic magnetic resonance imaging Time-signal intensity curve
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Dynamic imaging of metallic contamination plume based on self-potential data 被引量:5
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作者 Yi-an CUI Xiao-xiong ZHU +2 位作者 Wen-sheng WEI Jian-xin LIU Tie-gang TONG 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2017年第8期1822-1830,共9页
A dynamic imaging method for monitoring self-potential data was proposed.Based on the Darcy’s law and Archie’sformulas,a dynamic model was built as a state model to simulate the transportation of metallic ions in po... A dynamic imaging method for monitoring self-potential data was proposed.Based on the Darcy’s law and Archie’sformulas,a dynamic model was built as a state model to simulate the transportation of metallic ions in porous medium,and theNernst equation was used to calculate the redox potential of metallic ions for observation modeling.Then,the state model andobservation model form an extended Kalman filter cycle to perform dynamic imaging.The noise added synthetic data imaging testshows that the extended Kalman filter can effectively fuse the model evolution and observed self-potential data.The further sandboxmonitoring experiment also demonstrates that the self-potential can be used to monitor the activities of metallic ions and exactlyretrieve the dynamic process of metallic contamination. 展开更多
关键词 dynamic imaging SELF-POTENTIAL metallic contamination extended Kalman filter
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Laser Ablation Atomic Beam Apparatus with Time-Sliced Velocity Map Imaging for Studying State-to-State Metal Reaction Dynamics
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作者 董常武 刘嘉兴 +1 位作者 李芳芳 王凤燕 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2016年第1期99-104,I0002,共7页
We report a newly constructed laser ablation crossed molecular beam apparatus, equipped with time-sliced velocity map imaging technique, to study state-to-state metal atom reaction dynamics. Supersonic metal atomic be... We report a newly constructed laser ablation crossed molecular beam apparatus, equipped with time-sliced velocity map imaging technique, to study state-to-state metal atom reaction dynamics. Supersonic metal atomic beam is generated by laser vaporization of metal rod, and free expansion design without gas flow channel has been employed to obtain a good quality of metal atomic beam. We have chosen the crossed-beam reaction Al+O2 to test the performance of the new apparatus. Two-rotational-states selected AIO(X^2∑+, v=0, N and N+I4) products can be imaged via P(N) and R(N+14) branches of the Av=l band at the same wavelength, during (1+1) resonance-enhanced multi-photon ionization through the AIO(D2E+) intermediate state. In our experiment at 244.145 nm for simultaneous transitions of P(15) and R(29) branch, two rings in slice image were clearly distinguishable, corresponding to the AiO(v=0, N=IS) and AIO(v=0, N=29) states respectively. The energy difference between the two rotational levels is 403 cm^-1. The success of two states resolved in our apparatus suggests a better collisional energy resolution compared with the recent research study [J. Chem. Phys. 140, 214304 (2014)]. 展开更多
关键词 Time-sliced velocity map imaging Crossed beam Laser ablation Metal atom reaction dynamics
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Prediction of radiosensitivity in primary central nervous system germ cell tumors using dynamic contrast-enhanced magnetic resonance imaging 被引量:3
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作者 Chenlu Feng Peiyi Gao +4 位作者 Xiaoguang Qiu Tianyi Qian Yan Lin Jian Zhou Binbin Sui 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 2015年第3期231-238,共8页
Objective: To evaluate the feasibility of dynamic contrast-enhanced magnetic resonance imaging(DCEMRI) for predicting tumor response to radiotherapy in patients with suspected primary central nervous system(CNS) ... Objective: To evaluate the feasibility of dynamic contrast-enhanced magnetic resonance imaging(DCEMRI) for predicting tumor response to radiotherapy in patients with suspected primary central nervous system(CNS) germ cell tumors(GCTs).Methods: DCE-MRI parameters of 35 patients with suspected primary CNS GCTs were obtained prior to diagnostic radiation, using the Tofts and Kermode model. Radiosensitivity was determined in tumors diagnosed 2 weeks after radiation by observing changes in tumor size and markers as a response to MRI. Taking radiosensitivity as the gold standard, the cut-off value of DCE-MRI parameters was measured by receiver operating characteristic(ROC) curve. Diagnostic accuracy of DCE-MRI parameters for predicting radiosensitivity was evaluated by ROC curve.Results: A significant elevation in transfer constant(K^trans) and extravascular extracellular space(Ve)(P=0.000), as well as a significant reduction in rate constant(Kep)(P=0.000) was observed in tumors. K^trans, relative K^trans, and relative Kep of the responsive group were significantly higher than non-responsive groups. No significant difference was found in Kep, Ve, and relative Ve between the two groups. Relative K^trans showed the best diagnostic value in predicting radiosensitivity with a sensitivity of 100%, specificity of 91.7%, positive predictive value(PPV) of 95.8%, and negative predictive value(NPV) of 100%.Conclusions: Relative K^trans appeared promising in predicting tumor response to radiation therapy(RT). It is implied that DCE-MRI pre-treatment is a requisite step in diagnostic procedures and a novel and reliable approach to guide clinical choice of RT. 展开更多
关键词 dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) extravascular extracellular space germ cell tumors (GCTs) RADIOSENSITIVITY rate constant transfer constant
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Diagnosis value of diffusion-weighted MR imaging with dynamic enhanced scanning toward pancreatic endocrine tumors 被引量:1
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作者 Xingrong Hu Xiannian Cui +1 位作者 Jun Chen Biyong Tan 《The Chinese-German Journal of Clinical Oncology》 CAS 2014年第1期14-18,共5页
Objective: The aim of our study was to analysis the pictures of conventional magnetic resonance imaging (MR), diffusion-weighted imaging (DWl) and dynamic enhanced magnetic resonance imaging (DEMRI) of pancreat... Objective: The aim of our study was to analysis the pictures of conventional magnetic resonance imaging (MR), diffusion-weighted imaging (DWl) and dynamic enhanced magnetic resonance imaging (DEMRI) of pancreatic endocrine tumors (PETs), and evaluate diagnostic value of MR, DWl and DEMRI for diagnosing PETs. Methods: DWl and DEMRI scanning toward 13 patients with PETs being confirmed by surgical pathology before surgery on the basis of conventional MR scanning were carried out, and MR findings was analyzed retrospectively. Results: Of 13 patients with PETs there was 11 cases with single lesion, 2 with multiple, and had 15 lesions altogether, of which there were 3 lesions in pancreatic head, 1 in its neck, 2 in its body, 4 in its body and tail, 5 in its tail. MR findings: (1) T1WI signal was low or slightly lower (9/15), and equal ones (5/15); (2) T2WI showed high or slightly higher signal (10/15), and equal ones (5/15); (3) T1WI with fat suppression: the signal was low (11/15), mixed signal (2/15), and equal ones (2/15); (4) DWI: normal pancreatic tissue exhibited homogeneous intermediate signal, all 15 lesions were high or slightly higher signal, the measured ADC values of tissue of PETs was (1.124 ± 0.252) × 104 mm2/s, and the ADC value of normal pancreatic tissue (1.873 ± 0.157) × 10^3 mm2/s; (5) Enhanced (M3D/LAVA) scanning: among 13 patients with PETs there were 12 pancreatic lesions with significantly enhanced signals in the arterial phase in all 15, and significantly higher than normal pancreatic tissue, and two slight enhancement was slightly higher signal; and 1 no enhancement. Enhanced pattern: homogeneous enhancement were 6 lesions, and the heterogeneous 4, and the edge ring 5. Conclusion: MR and DWl combining with DEMRI help qualitative diagnosis of pancreatic endocrine tumors. 展开更多
关键词 PANCREAS endocrine tumors magnetic resonance imaging diffusion-weighted imaging dynamic enhancement
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Video-rate multimodal multiphoton imaging and three-dimensional characterization of cellular dynamics in wounded skin 被引量:1
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作者 Joanne Li Madison N.Wilson +4 位作者 Andrew J.Bower Marina Marjanovic Eric J.Chaney Ronit Barkalifa Stephen A.Boppart 《Journal of Innovative Optical Health Sciences》 SCIE EI CAS 2020年第2期70-80,共11页
To date,numerous studies have been performed to elucidate the complex cellular dynamics in skin diseases,but few have attempted to characterize these cellular events under conditions similar to the native environment.... To date,numerous studies have been performed to elucidate the complex cellular dynamics in skin diseases,but few have attempted to characterize these cellular events under conditions similar to the native environment.To address this challenge,a three-dimensional(3D)multimodal analysis platform was developed for characterizing in vivo cellular dynamics in skin,which was then utilized to process in vivo wound healing data to demonstrate its applicability.Special attention is focused on in vivo biological parameters that are difficult to study with ex vivo analysis,including 3D cell tracking and techniques to connect biological information obtained from different imaging modalities.These results here open new possibilities for evaluating 3D cellular dynamics in vivo,and can potentially provide new tools for characterizing the skin microenvironment and pathologies in the future. 展开更多
关键词 Cellular dynamics multimodal imaging multiphoton microscopy
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Review:Coincidence Momentum Imaging:Principle and Application in Molecular Reaction Dynamics 被引量:1
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作者 Li Zhang Huailiang Xu 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2018年第4期1-14,共14页
Coincidence Momentum Imaging(CMI) is a powerful imaging technique that can determine the full momentum vectors of all particles released from a single parent molecule in coincidence and thus provide detailed informati... Coincidence Momentum Imaging(CMI) is a powerful imaging technique that can determine the full momentum vectors of all particles released from a single parent molecule in coincidence and thus provide detailed information on transient molecular structures.So far,the CMI technique has been extensively employed for investigating a variety of molecular reaction dynamics induced,e.g.,by particle collisions,intense laser fields and synchrotron radiation.In this article,we first introduce the principle of the CMI technique,which is followed by several typical experimental designs of the CMI systems realizing the coincidence momentum detections.We then present representative examples of studying molecular reaction dynamics using the CMI technique. 展开更多
关键词 Coincidence momentum imaging Intense laser fields Molecular reaction dynamics
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Application of dynamic contrast-enhanced magnetic resonance imaging(DCE-MRI)combined with magnetic resonance spectroscopy(MRS)in prostate cancer diagnosis 被引量:1
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作者 Yakun He Min Wang +1 位作者 Heping Deng Jin Ren 《Oncology and Translational Medicine》 CAS 2021年第1期31-34,共4页
Objective The aim of the study was to investigate the application of dynamic contrast-enhanced magnetic resonance imaging(DCE-MRI)combined with magnetic resonance spectroscopy(MRS)in prostate cancer diagnosis.Methods ... Objective The aim of the study was to investigate the application of dynamic contrast-enhanced magnetic resonance imaging(DCE-MRI)combined with magnetic resonance spectroscopy(MRS)in prostate cancer diagnosis.Methods In the outpatient department of our hospital(Sichuan Cancer Hospital,Chengdu,China),60 patients diagnosed with prostate disease were selected randomly and included in a prostate cancer group,60 patients with benign prostatic hyperplasia were included in a proliferation group,and 60 healthy subjects were included in a control group,from January 2013 to January 2017.Using Siemens Avanto 1.5 T high-field superconducting MRI for DCE-MRI and MRS scans,after the MRS scan was completed,we used the workstation spectroscopy tab spectral analysis,and eventually obtained the crest lines of the prostate metabolites choline(Cho),creatine(Cr),citrate(Cit),and the values of Cho/Cit,and(Cho+Cr)/Cit.Results Participants who had undergone 21-s,1-min,and 2-min dynamic contrast-enhanced MR revealed significant variations among the three groups.The spectral analysis of the three groups revealed a significant variation as well.DCE-MRI and MRS combined had a sensitivity of 89.67%,specificity of 95.78%,and accuracy of 94.34%.Conclusion DCE-MRI combined with MRS is of great value in the diagnosis of prostate cancer. 展开更多
关键词 prostate cancer magnetic resonance imaging(MRI) dynamic contrast-enhanced(DCE) spectroscopy
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