1.Study on direct MRI detection of neuronal magnetic field
Yingling HUANG ; Hongchuan XIONG ; Dezhong YAO
International Journal of Biomedical Engineering 2008;31(6):337-341
With the development of medical imaging technology, hemodynamics-based functional magnetic resonance imaging (fMRI) has gradually become one of the major tools to investigate human brain function, however, it is of limited temporal resolution. In recent years, neuronal current MRI (nc-MRI) was proposed as a new imaging method to directly map the magnetic field change caused by neural activities. Theoretically, nc-MRI can non-inva- sively locate brain activities with very high spatial and temporal resolution, thus it may greatly improve the study of human brain function. This paper reviews the construction mechanism of nc-MRI, including theoretical model of the neuronal magnetic field and signal source. Arithmetic simulation of nc-MRI signal with an illustration of our work on simulation of a dendrite branch magnetic field is presented. New development of the experimental studies and foreground of nc-MRI area are discussed.
2.TACE combined with sorafenib for inoperable hepatocellular carcinoma:analysis of treatment interval
Xuesong YAO ; Dong YAN ; Huiying ZENG ; Dezhong LIU ; Huai LI
Journal of Interventional Radiology 2014;(9):769-771
Objective To investigate the clinical efficacy of transarterial chemoembolization (TACE) combined with sorafenib for the treatment of inoperable hepatocellular carcinoma (HCC), and to discuss the influence of treatment interval on the survival time. Methods During the period from July 2008 to May 2011 at authors’ hospital, a total of 50 patients with inoperable HCC were treated with TACE together with sorafenib. The treatment intervals between each TACE procedure were recorded. The results were analyzed. Results Up to Dec. 31, 2011, the median follow-up time of the 50 patients was 310 days. The mean interval between TACE treatments was 69 days before the combination treatment was employed , while the mean interval was 112 days after the combination treatment started , and the longest interval was 648 days. Conclusion Combination treatment TACE with sorafenib can remarkably prolong the treatment interval in patients with inoperable HCC, thus the patient can get more survival benefits.
3.The application of C- arm CT imaging technique in evaluating the efficacy of TACE for hepatocellular carcinoma
Xuesong YAO ; Dong YAN ; Huiying ZENG ; Dezhong LIU ; Huai LI
Journal of Interventional Radiology 2014;(7):588-592
Objective To investigate the application of C- arm CT imaging technique in evaluating the efficacy of transarterial chemoembolization(TACE) for hepatocellular carcinoma(HCC). Methods During the period from Sep. 2012 to Mar. 2013 at authors’ hospital, C- arm CT scanning was employed during the performance of TACE in 80 patients with HCC. The residual active tumor lesions, Lipiodol deposition and the embolization of the feeding arteries after TACE therapy were assessed by C- arm CT plain scan images and the images of early artery phase and parenchymal phase, as well as the post- processing images. The efficacy of TACE was thus evaluated. Results A total of 139 hepatic tumors were detected in 80 patients by C- arm CT imaging. C- arm CT scanning performed immediately after TACE showed that satisfactory result was obtained in 128 lesions of 75 patients(128/139, 92.9%). Fewer, medium and more residual active tumors were seen in 78, 29 and 21 lesions respectively, while dense, moderate and thin Lipiodol deposition was seen in 64, 39 and 25 lesions respectively. After TACE therapy obvious decrease in blood supply was demonstrated in 101 lesions, while no obvious decrease in blood supply was seen in 27 lesions. Conclusion C- arm CT scanning after TACE for patients with HCC can conveniently, accurately and comprehensively reveal the residual active tumors, Lipiodol deposition and embolization status of feeding arteries. Therefore, this technique should be regarded as an important means to evaluate the efficacy of TACE.
4.A comparison of the mRECIST and RECIST criteria in the efficacy assessment of TACE combined with sorafenib in the treatment of unresectable hepatocellular carcinoma
Xuesong YAO ; Dong YAN ; Dezhong LIU ; Huiying ZENG ; Huai LI
Chinese Journal of Hepatobiliary Surgery 2013;(5):332-336
Objective To evaluate the value of the mRECIST criteria in assessing the efficacy of transcatheter arterial chemoembolization(TACE) combined with sorafenib in the treatment of hepatocellular carcinoma (HCC).Methods A total of 35 patients who were treated with a combination of TACE and sorafenib for unresectable hepatocellular carcinoma fulfilled the mRECIST and RECIST criteria in our hospital from June 2011 to November 2012.Enhanced CT and/or enhanced MRI were used before (baseline) and after (3 month reexamination) combination treatment in our hospital.The mRECIST and RECIST criteria were used to evaluate the efficacy,and these efficacy assessments were compared.Results In the RECIST criteria,complete remission (CR) was 0%,partial remission (PR) was 2.9%,stable disease (SD) was 85.7%%,and progressive disease (PD) was 11.4%%.In the mRECIST criteria,CR was 8.6%,PR was 51.4%,SD was 34.3%,and PD was 5.7%.For the RECIST criteria,the objective response rate (CR+-PR) was 2.9%,the disease control rate (CR+PR+SD) was 88.6%,and the disease progression rate was 11.4%.For the mRECIST criteria,the objective criteria was 60%,the disease control rate was 94.3%,and the disease progression rate was 5.7 %.The difference between the efficacy assessment results of mRECIST and RECIST was statisti cally significant(P<0.001).Conclusion The mRECIST criteria can evaluate the efficacy of target le sions based on viable tumors,which is more adaptive to TACE and targeted drugs with new mecha nisms.
5.Anesthesia gas concentration measure device based on NDIR technique
Qiang LIU ; Dezhong YAO ; Xinsheng LI ; Wei ZHANG ; Huiling ZHOU
Chinese Medical Equipment Journal 2004;0(07):-
In this paper, a newly-designed device is introduced, which uses non-dispersive infrared absorption technique to acquire anesthesia gas concentration signal and to perform side-stream measurement in the air way. The microcontroller is adopted to implement data acquisition, data processing and then to transmit the data to the PC screen, thus the real-time continuous invasive concentration monitoring of the anesthesia gas in the patient's respiratory air can be realized during a surgical operation.
6.Study on neurofeedback system based on electroencephalogram signals.
Xianjie PU ; Tiejun LIU ; Qiang WU ; Rui ZHANG ; Peng XU ; Ke LI ; Yang XIA ; Dezhong YAO
Journal of Biomedical Engineering 2014;31(4):894-898
Neurofeedback, as an alternative treatment method of behavioral medicine, is a technique which translates the electroencephalogram (EEG) signals to styles as sounds or animation to help people understand their own physical status and learn to enhance or suppress certain EEG signals to regulate their own brain functions after several repeated trainings. This paper develops a neurofeedback system on the foundation of brain-computer interface technique. The EEG features are extracted through real-time signal process and then translated to feedback information. Two feedback screens are designed for relaxation training and attention training individually. The veracity and feasibility of the neurofeedback system are validated through system simulation and preliminary experiment.
Brain-Computer Interfaces
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Electroencephalography
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Female
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Humans
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Neurofeedback
7.Spatial spectra of neural electric activities and their application in study of visual spatial selective attention.
Journal of Biomedical Engineering 2004;21(2):241-245
In this paper, the spatial spectra of neural electric activities and their primary application to visual spatial selective attention are presented. Based on the spherical harmonic spectra inversion by equivalent distributed dipole layer technique, novel latitude spectra S(1) and longitudinal spectra S(m) are defined as the description of spatial spectra of brain electric activities. When the latitude and longitudinal spectra are applied to the event-related potentials (ERP) of spatial selective attention to the right and left visual fields, the temporal structures of spatial spectra of all temporal sample points show meaningful delay and amplitude differences of components between 100 ms and 200 ms for attended and unattended stimulus conditions. These facts indicate that the latitude and longitudinal spatial spectra concept is useful in study of cognitive brain research.
Attention
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physiology
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Brain
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physiology
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Brain Mapping
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Electroencephalography
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Event-Related Potentials, P300
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physiology
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Evoked Potentials, Visual
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physiology
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Models, Neurological
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Pattern Recognition, Visual
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physiology
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Photic Stimulation
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Space Perception
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Spatial Behavior
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physiology
8.On the study methods of electroencephalograph synchronization.
Journal of Biomedical Engineering 2009;26(6):1353-1357
Synchronous brain activities are considered as an indicator of the functional binding or integration. In this paper, based on the neural electric activities at various spatial scales, we explained the basic concept and measuring index of neural synchronization; then we summarized the main signal processing methods developed for phase synchronization analysis of electroencephalograph (EEG), including the conventional signal processing method, and modern signal modeling approaches. Finally, the main differences among the different methods were compared and some critical problems in the study of EEG synchronization were discussed.
Algorithms
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Analysis of Variance
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Brain
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physiology
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Cognition
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physiology
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Cortical Synchronization
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Electroencephalography
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methods
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Humans
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Signal Processing, Computer-Assisted
9.Rish factors and drug resistance of nosocomial infections caused by multidrug resistant Pseudomonas aeruginosa
Fang DENG ; Jian ZHANG ; Shiyong ZHANG ; Qisheng PENG ; Dezhong SHU ; Yao MU
Chongqing Medicine 2013;(35):4304-4306
Objective To analysis the risk factors and drug resistance of multidrug-resistant pseudomonas aeruginosa(MDRP) infection and to provide the basis for clinical anti-infective therapy .Methods Predisposing factors and drug resistance to clinical commonly used antibacterial drugs of MDRP which were separated from September 2010 to December 2011 were adopted for retro-spective analysis .Results A total of 235 hospital MDRP infection were collected ,97 multidrug resistant strains were concluded ,the separation rate was 41 .2% .The separation rate of ICU and neurosurgery were higher ,account for 35 .54% and 22 .31% respective-ly .The main resource of specimen is respiratory tract ,about 75 .21% .The resistance of MDRP was very serious .The resistant rate of Amikacin was the lowest ,account for 37 .11% ,followed by piperacillin/tazobactam ,ceftazidime ,account for 47 .4% and 48 .45%respectively .The resistant rate of other antimicrobial agents were greater than 50% .Advanced age ,serious underlying diseases ,long hospital stay ,long-term repeated application of broad-spectrum antimicrobial drugs ,admission to ICU ,invasive treatment operations were the risk factors for MDRP resistance .Conclusion The resistance is very serious ,in order to reduce the generation and spread of drug-resistant strains ,the hospital infection control ,drug resistance monitoring ,rational use of antimicrobial drugs and prevention of cross-infections should be strengthened .
10.Applying exponent method of density to amend bone's edge of X-ray image.
Journal of Biomedical Engineering 2005;22(1):129-132
Because of the difference in organic density, a simple and effective method for exponent restraint of active edge is applied to X-ray image of bone. And it is easy to use histogram method to get the active image of bone. At last, by associating it with Canny method, the edge of bone can be abstracted from a complex X-ray image.
Algorithms
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Bone and Bones
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diagnostic imaging
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Humans
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Radiographic Image Enhancement
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methods
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Radiographic Image Interpretation, Computer-Assisted
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methods