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1.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-828202

RESUMO

A wearable wireless health monitoring system for drug addicts in compulsory rehabilitation centers was proposed. The system can continuously monitor multiple physiological parameters of drug addicts in real time, and issue early warning information when abnormal physiological parameters occur, so as to play the role of timely medical practice. In addition, this study proposes a convolutional neural network (CNN)model, which can evaluate the health status of drug addicts based on multiple physiological parameters. Experiments show that the model can be applied to the task of body state recognition in the open physiological parameter data set, and the recognition accuracy can reach up to 100% in a single physiological parameter data set; when the whole physiological data set is used, the recognition accuracy can reach 99.1%. The recognition accuracy exceeds the performance of the traditional pattern recognition method on this task, which verifies the superiority of the model.


Assuntos
Algoritmos , Eletrocardiografia , Monitorização Fisiológica , Redes Neurais de Computação , Dispositivos Eletrônicos Vestíveis
2.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-265581

RESUMO

Traditional capsule image collects and transmits analog image, with weak anti-interference ability, low frame rate, low resolution. This paper presents a new digital image capsule, which collects and transmits digital image, with frame rate up to 30 frames/sec and pixels resolution of 400 x 400. The image is compressed in the capsule, and is transmitted to the outside of the capsule for decompression and interpolation. A new type of interpolation algorithm is proposed, which is based on the relationship between the image planes, to obtain higher quality colour images. capsule endoscopy, digital image, SCCB protocol, image interpolation


Assuntos
Algoritmos , Endoscopia por Cápsula , Desenho de Equipamento , Processamento de Imagem Assistida por Computador
3.
Journal of Biomedical Engineering ; (6): 1348-1353, 2015.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-357869

RESUMO

Autofluorescence has great advantage on detecting premalignant lesions and early cancers which are not detectable by conventional white light endoscopy (WLE). In this review, the recent advances in autofluorescence for diagnosis of precancerous lesions and early cancers are presented. Varieties of endogenous fluorophores in biological tissues, the potential mechanisms of the autofluorescence differences between normal and abnormal tissues, the selection of light source and optimal excitation wavelengths, and effective algorithms for processing autofluorescence data are highlighted. Finally, the shortages and improvement directions of autofluorescence technique for the diagnosis of precancerous lesions and early cancers are briefly discussed.


Assuntos
Humanos , Detecção Precoce de Câncer , Métodos , Neoplasias Esofágicas , Diagnóstico , Fluorescência
4.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-266698

RESUMO

With the development of capsule endoscopy, developing active capsule endoscopy robot becomes a growing trend. Although stomach diagnosis with robot has been put into clinical test, the realization of the complete intestinal capsule endoscopy is still a difficulty. This paper reports the status quo of the research process for intestinal capsule endoscopy robot, and analyzes their advantages, defects and prospects for development, which provides reference for the research of intestinal capsule endoscopy robot.


Assuntos
Humanos , Endoscopia por Cápsula , Intestinos , Robótica
5.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-310289

RESUMO

Because the huge number of images of the digestive tract by Wireless Capsule Endoscopy (WCE) are left to the medical personnels detected by their eyes, huge burden leaves to doctors. This article provides a classification of method based on SVM (Support Vector Machine) for the capsule endoscopy bleeding intelligent recognition. We created a new kind of feature parameter, and the experiment result can reach 83% specificity and 94% sensitivity.


Assuntos
Humanos , Endoscopia por Cápsula , Trato Gastrointestinal , Patologia , Hemorragia , Diagnóstico , Sensibilidade e Especificidade , Máquina de Vetores de Suporte
6.
J Med Eng Technol ; 38(7): 351-8, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25082182

RESUMO

Wireless power transmission is considered a practical way of overcoming the power shortage of wireless capsule endoscopy (VCE). However, most patients cannot tolerate the long hours of lying in a fixed transmitting coil during diagnosis. To develop a portable wireless power transmission system for VCE, a compact transmitting coil and a portable inverter circuit driven by rechargeable batteries are proposed. The couple coils, optimized considering the stability and safety conditions, are 28 turns of transmitting coil and six strands of receiving coil. The driven circuit is designed according to the portable principle. Experiments show that the integrated system could continuously supply power to a dual-head VCE for more than 8 h at a frame rate of 30 frames per second with resolution of 320 × 240. The portable VCE exhibits potential for clinical applications, but requires further improvement and tests.


Assuntos
Endoscopia por Cápsula/instrumentação , Fontes de Energia Elétrica , Tecnologia sem Fio/instrumentação , Animais , Cápsulas Endoscópicas , Desenho de Equipamento , Suínos
7.
Physiol Meas ; 32(10): 1561-73, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21873764

RESUMO

Multipurpose active capsule endoscopes have drawn considerable attention in recent years, but these devices continue to suffer from energy limitations. A wireless power supply system is regarded as a practical way to overcome the power shortage problem in such devices. This paper focuses on the efficiency optimization of a wireless energy supply system with size and safety constraints. A mathematical programming model in which these constraints are considered is proposed for transmission efficiency, optimal frequency and current, and overall system effectiveness. To verify the feasibility of the proposed method, we use a wireless active capsule endoscope as an illustrative example. The achieved efficiency can be regarded as an index for evaluating the system, and the proposed approach can be used to direct the design of transmitting and receiving coils.


Assuntos
Cápsulas Endoscópicas , Endoscopia por Cápsula/instrumentação , Endoscopia por Cápsula/métodos , Eletricidade , Animais , Simulação por Computador , Impedância Elétrica , Humanos , Técnicas In Vitro , Sus scrofa , Temperatura
8.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-341643

RESUMO

In order to determine the position of an intra-body microcapsule, the system based on alternating magnetic field has been promoted. According to the theory of three-dimensional localization system, the mathematical model has been ratiocinated. Composing and software design of the system are given. The result of the experiment has demonstrated that the system is feasible and it performs with high precision. The position error is less than 3 cm when the range is between 3 and 30cm. And the system has good anti-interference ability.


Assuntos
Humanos , Algoritmos , Endoscopia por Cápsula , Campos Eletromagnéticos , Imageamento Tridimensional , Magnetismo , Modelos Teóricos , Imagens de Fantasmas , Software
9.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-341591

RESUMO

In order to deliver power to the capsule endoscope, whose position and orientation are always changing when traveling along the alimentary tract, a wireless power transmission system based on electromagnetic coupling was proposed. The system is composed of Helmholtz transmitting coil and three-dimensional receiving coil. Helmholtz coil outside the body generates a uniform magnetic field covering the whole alimentary tract; three-dimensional coil inside retrieves stable power regardless of its position and orientation. The transmitter and receiver were designed and implemented, and the experiments validated the feasibility of the system. The results show that at least 320 mW of usable power can be transmitted to capsule endoscope when its position and orientation are changing at random and the transmitting power is 25W.


Assuntos
Humanos , Cápsulas Endoscópicas , Endoscopia por Cápsula , Condutividade Elétrica , Fontes de Energia Elétrica , Campos Eletromagnéticos , Desenho de Equipamento , Gastroenteropatias , Diagnóstico
10.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-280244

RESUMO

A noninvasive measuring system for human GI physiological signals has been designed, and human GI physiological realtime parameters are acquired in the normal physiological state of human. In this paper is mainly discussed the design of "In-vitro data recorder" of a noninvasive measuring system for human GI physiological signals. By experiments, the portable "In-vitro data recorder" works normally and reliably; it can meet the needs of clinical application.


Assuntos
Humanos , Cápsulas , Eletrônica Médica , Métodos , Desenho de Equipamento , Trânsito Gastrointestinal , Fisiologia , Monitorização Fisiológica , Métodos , Processamento de Sinais Assistido por Computador
11.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-230655

RESUMO

A wireless power transmission method based on electromagnetic coupling was proposed for gastrointestinal microsystems. We analyzed the coupling coefficient, taking coils' misalignments into account by calculating mutual inductance. A power transmission model was built up. And based on this model, the electric parameters of maximizing the received power were deducted under weakly coupling condition. From the transmitting efficiency formula, we found two ways to enhance the efficiency. The transmission power was more than 200mW in our experiments when the receiving coil was located at the center of transmitting coil. This validated the method feasibility.


Assuntos
Humanos , Cápsulas Endoscópicas , Endoscopia por Cápsula , Métodos , Fontes de Energia Elétrica , Campos Eletromagnéticos , Desenho de Equipamento , Gastroenteropatias , Diagnóstico , Miniaturização
12.
Journal of Biomedical Engineering ; (6): 1442-1445, 2008.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-318133

RESUMO

Artificial heart is an effective device in solving insufficient native heart supply for heart transplant, and the research and application of novel actuators play an important role in the development of artificial heart. In this paper, artificial muscle is introduced as the actuators of direct cardiac compression assist, and some of its parameters are compared with those of native heart muscle. The open problems are also discussed.


Assuntos
Humanos , Órgãos Artificiais , Circulação Assistida , Materiais Biocompatíveis , Desenho de Equipamento , Coração Auxiliar , Músculos
13.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-291268

RESUMO

The work of research and development of noninvasive monitoring system for human GI (gastrointestinal tract) has been very successful all over the world, and without questions, the system as such will extensively be applied in the future. However, the method for localization of the monitoring capsule in the system is not perfect. This paper reports the status quo of the research process for the capsule localization system, and analyzes their advantages and defects.


Assuntos
Humanos , Técnicas Biossensoriais , Cápsulas Endoscópicas , Endoscopia por Cápsula , Métodos , Desenho de Equipamento , Trato Gastrointestinal
14.
Journal of Biomedical Engineering ; (6): 1079-1083, 2008.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-342679

RESUMO

Pan-colonic motility was studied under normal conditions with a novel capsule-style system. A single use telemetry capsule embedded with one pressure sensor was ingested by subjects. It is capable of transmitting colonic pressure wirelessly greater than 130 h. Time of capsule entering segmental colon was determined by ultrasonic detection for tracing the batteries in capsule. The ultrasonic electrodes were mounted on the surface of subjects' ileocecum, navel as well as the junction of left colon and rectosigmoid colon in sequence. They were identified by abdominal X-rays with radiopaque markers. The confirming X-rays showed all telemetry capsules were detected successfully when passing through the key points in colon. A total of 613 h of colorectal recording was obtained from 20 healthy subjects. When compared with the parameters in the time of waking, the number of contractions and the area under contractions were significantly (P<0.05) decreased during sleep (21 +/- 5 vs 15 +/- 4 h(-1); 463 +/- 54 vs 342 +/- 45 mmHg x s x min(-1)). The colonic motility exhibited significant regional variation in the circadian behavior, as well as in its response to waking and meal. The clinical study proved the reliability and non-invasiveness of the system. It may represent a useful tool for the study on physiology and pathology of colonic motor disorders.


Assuntos
Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem , Cápsulas , Colo , Fisiologia , Motilidade Gastrointestinal , Fisiologia , Manometria , Métodos , Pressão , Telemetria , Ultrassom
15.
Physiol Meas ; 28(3): N9-18, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17322587

RESUMO

Much research on the development of a robotic capsule and microrobot for the diagnosis of gastrointestinal diseases has been carried out. The powering of these microsystems is becoming very important as the implementation of such systems is becoming more feasible by advances in relevant technologies. A wireless power transmission system employing two coils, based on inductive coupling, is discussed in this note. The coupling coefficient between the two coils was measured on axial, lateral and pitch misalignment. The power transmission efficiency was deduced and optimized by selecting proper tuning capacitors and transmission frequency. A serial resonant circuit (SRC) on a receiving side is more adaptive by comparison with parallel resonant circuit (PRC) topology. A multi-receiving coil structure was proposed and examined in an attempt to resolve the orientation indetermination problem of a receiving coil. Experiments show that a dc power level up to 170 mW, with an efficiency of 1.3%, could be steadily received when the receiving coil was placed at the center of the transmitting coil, which can meet the requirement for electric power of some microsystems.


Assuntos
Cápsulas Endoscópicas , Fontes de Energia Elétrica , Gastroenteropatias/diagnóstico , Humanos
16.
Journal of Biomedical Engineering ; (6): 1148-1151, 2007.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-230731

RESUMO

Localization system was designed based on analytic equation of permanent magnetic field to localize the swallowing electrical capsule in the gastrointestinal. Algorithm was presented and experiment was made. Two three-axis magnetism sensors were mounted in the capsule. The non linear equations set of sensor's output and capsule's position and attitude was created according to space position and attitude relationship model. The equations set was resolved with numerical method. Comparison between the calculation value and expected value showed that this method was feasible.


Assuntos
Humanos , Algoritmos , Técnicas Biossensoriais , Cápsulas , Campos Eletromagnéticos , Elétrons , Gastroenteropatias , Diagnóstico , Trato Gastrointestinal
17.
Journal of Biomedical Engineering ; (6): 1079-1083, 2007.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-346006

RESUMO

Using the method of detrended fluctuation analysis (DFA) and power spectral analysis (PSA), the paper deals with the characteristics of long-range correlations of colonic pressure activities and their surrogate data of healthy subjects. The DFA is a period representation of such correlations, whereas the PSA is a frequency representation. The analysis of the two methods consistently shows that there are long memories in colonic pressure activities and there exist long-range correlations, whereas there are no such long memories and long-range correlations in the surrogate data, whose sequential orders are randomly shuffled. The results to some extent indicate that human colonic pressure activities with normal motilities do have long memories, but these memories may be weaker or may even be destroyed with dysmotilities.


Assuntos
Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Colo , Fisiologia , Interpretação Estatística de Dados , Pressão , Processamento de Sinais Assistido por Computador
18.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-249575

RESUMO

Many diseases of gastrointestinal tract have close relation to the changes in gastrointestinal (GI) motility. Making use of the technique of MEMS, we developed a micro-interposed system to monitor the motility and pH value of the whole GI tract under normal physical state. This paper focuses on an automatic analysis of the acquired signal to draw conclusions for aiding diagnosis of diseases. The techniques of smoothing signal, removing singular value, feature extraction and selection as well as classification of normal and abnormal samples are discussed in details. These techniques provide a comprehensive method for analyzing long-term motility recordings which will complete the function of the in vivo monitoring system and serve for medical applications.


Assuntos
Humanos , Gastroenteropatias , Motilidade Gastrointestinal , Fisiologia , Processamento de Sinais Assistido por Computador
19.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-249529

RESUMO

Craving of drug addicts for drugs is the most important factor that causes relapse. On-line, objective and quantificational measurement of craving is of certain value in predicting relapse and drug-seeking behavior of addicts. Some common methods used to measure craving are reviewed and their shortcomings are analyzed. Aiming at characteristics, analysis methods, typical application of electroencephalography (EEG) and characteristics of craving, we have a discussion about the possibility of using EEG to measure craving. In addition, some related problems and difficulties are probed. These analyses are helpful to the study of craving.


Assuntos
Humanos , Comportamento Aditivo , Diagnóstico , Psicologia , Eletroencefalografia , Autorrevelação , Sensibilidade e Especificidade , Síndrome de Abstinência a Substâncias , Diagnóstico
20.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-577050

RESUMO

Objective To develop a method for localizing a detecting capsule in the gastrointestinal tract.Methods A three-axis magnetic sensor was sealed in the detecting capsule.Three flat coils were fixed on patients' back.The coils were excited one by one to generate electromagnetic fields.The position and the orientation of the capsule could be determined by telemetering the signals from the magnetic sensor incorporated in the capsule.Results The telemetric localization system worked successfully.A localization model describing the relationship between the magnetic field strength and the position and orientation of the capsule,was correctly established basing on the principle of magnetic dipoles,and neural network algorithm was employed to solve a non-linear equation set.Conclusion The results showed that the localization method is feasible and the precision is higher than existing methods.The localization device can perform consecutive tracking and can be made into a portable type.After putting into practice,the device can also be used in food selection for astronauts by monitoring their gastrointestinal parameters in space.

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