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1.
Acta Pharmaceutica Sinica B ; (6): 1175-1199, 2021.
Article Dans Anglais | WPRIM | ID: wpr-881192

Résumé

Therapeutic nanoparticles are designed to enhance efficacy, real-time monitoring, targeting accuracy, biocompatibility, biodegradability, safety, and the synergy of diagnosis and treatment of diseases by leveraging the unique physicochemical and biological properties of well-developed bio-nanomaterials. Recently, bio-inspired metal nanoclusters (NCs) consisting of several to roughly dozens of atoms (<2 nm) have attracted increasing research interest, owing to their ultrafine size, tunable fluorescent capability, good biocompatibility, variable metallic composition, and extensive surface bio-functionalization. Hybrid core-shell nanostructures that effectively incorporate unique fluorescent inorganic moieties with various biomolecules, such as proteins (enzymes, antigens, and antibodies), DNA, and specific cells, create fluorescently visualized molecular nanoparticle. The resultant nanoparticles possess combinatorial properties and synergistic efficacy, such as simplicity, active bio-responsiveness, improved applicability, and low cost, for combination therapy, such as accurate targeting, bioimaging, and enhanced therapeutic and biocatalytic effects. In contrast to larger nanoparticles, bio-inspired metal NCs allow rapid renal clearance and better pharmacokinetics in biological systems. Notably, advances in nanoscience, interfacial chemistry, and biotechnologies have further spurred researchers to explore bio-inspired metal NCs for therapeutic purposes. The current review presents a comprehensive and timely overview of various metal NCs for various therapeutic applications, with a special emphasis on the design rationale behind the use of biomolecules/cells as the main scaffolds. In the different hybrid platform, we summarize the current challenges and emerging perspectives, which are expected to offer in-depth insight into the rational design of bio-inspired metal NCs for personalized treatment and clinical translation.

2.
Journal of Biomedical Engineering ; (6): 481-487, 2018.
Article Dans Chinois | WPRIM | ID: wpr-687605

Résumé

Liver cancer is a common type of malignant tumor in digestive system. At present, computed tomography (CT) plays an important role in the diagnosis and treatment of liver cancer. Segmentation of tumor lesions based on CT is thus critical in clinical diagnosis and treatment. Due to the limitations of manual segmentation, such as inefficiency and subjectivity, the automatic and accurate segmentation based on advanced computational techniques is becoming more and more popular. In this review, we summarize the research progress of automatic segmentation of liver cancer lesions based on CT scans. By comparing and analyzing the results of experiments, this review evaluate various methods objectively, so that researchers in related fields can better understand the current research progress of liver cancer segmentation based on CT scans.

3.
Chinese Journal of Postgraduates of Medicine ; (36): 438-441, 2017.
Article Dans Chinois | WPRIM | ID: wpr-616037

Résumé

Objective To investigate the diagnosis and treatment of primary presacral tumor. Methods The clinical data of 18 patients with primary presacral tumor were retrospectively analyzed. Results Preoperative diagnosis of primary presacral tumor depended on digital rectal examination, endorectal ultrasound, CT, MRI, et al. The surgical approaches of 18 cases included posterior approach (14 cases) and abdominoperineal approach (4 cases). All tumors were completely resected. Postoperative complications were rectal injury (1 case) and wound infection (2 cases), which were cured by symptomatic treatment. Postoperative pathological results showed that 15 cases had benign lesions and 3 cases had malignant lesions. Sixteen patients were followed up from 0.5 to 5.0 years, with recurrence in 2 cases and death in 2 cases. Conclusions Primary presacral tumor should be treated with operation. Sufficient preoperative examination, personalized operative planning, subtle manipulation operative procedures with an experienced multidisciplinary team, are the important points in preventing or reducing recurrence. Endorectal ultrasound plays an important role in the diagnosis and treatment of primary presacral tumor.

4.
Chinese Journal of Behavioral Medicine and Brain Science ; (12): 754-759, 2017.
Article Dans Chinois | WPRIM | ID: wpr-613081

Résumé

Child and adolescent mental disorders are common disorders with various symptoms,and attracting more attention due to the increasing prevalence.Mental disorders,especially the attention-deficit hyperactivity disorder (ADHD) and the autism spectrum disorder (ASD),have great influence on the development of children and adolescents.Nowadays,the biomarkers from neuroimaging such as magnetic resonance imaging (MRI) have a great importance on the diagnosis of mental disorders,and machine learning has been proved to be very powerful in the processing for neuroimages.Nowadays,many researchers are focusing on the studies of computer-aided diagnosis (CAD) based on machine learning and neuroimaging.In this review,the technical details of machine learning based CAD of child and adolescent mental disorders are briefly introduced,and the research progress in CAD of ADHD and ASD based on machine learning and structural MRI are summarized.These studies showed that many machine learning methods have been used in the diagnosis of child and adolescent mental disorders,but the relevant methods cannot be applied to clinical diagnosis.Further studies should be conducted to improve the diagnostic ability of machine learning methods from multiple perspectives,and provide an objective and reliable tool for the clinical diagnosis of child and adolescent mental disorders.

5.
Chinese Journal of Medical Imaging Technology ; (12): 1315-1320, 2017.
Article Dans Chinois | WPRIM | ID: wpr-607794

Résumé

Objective To evaluate the value of acoustic radiation force impulse (ARFI) elastography in assessment of nonalcoholic fatty liver disease (NAFLD) and hepatic fibrosis in rats.Methods Models with various degrees of NAFLD severity were conducted in 110 rats by feeding high fat emulsion.The right liver lobe of rat models were processed and embedded in a fabricated gelatin solution to measure the shear wave velocity (SWV) by ARFI.And the other liver lobes were used for histologic assessment.Based on NAFLD activity score (NAS),the final pathologic NAFLD diagnosis were considered as normal group (NAS=0),simple steatosis (SS) group (1≤NAS≤2),borderline (3≤NAS≤4) group and nonalcoholic steatohepatitis (NASH) group (NAS≥5).The diagnostic accuracy of the SWV parameters in evaluating NAFLD severity and fibrosis stages was studied using ROC curves.Results The difference of SWV values among normal group,SS group,borderline group and NASH group was statistically significant (F=31.53,P<0.001).Taking SWV≥ 2.54 m/s as the diagnostic standard to differentiate normal rats from rats with SS,and SWV≥2.90 m/s to differentiate SS from NASH in rats,the area under ROC curve (AUC) was 0.922 (95%CI [0.871,0.973],P<0.001) and 0.882 (95% CI [0.807,0.956],P<0.001) respectively.The sensitivity and specificity were 93.5 % and 100 % for differentiating normal and SS groups,83.3 % and 84.2 % for differentiating SS and NASH groups.Taking SWV≥3.48 m/s as cutoff to predict fibrosis (≥F2 stage),the AUC was 0.963 (95%CI [0.909,1.000],P<0.001),the sensitivity was 92.9% and the specificity was 97.6%.Taking SWV≥3.61 m/s as cutoff to predict severe fibrosis (≥F3 stage),the AUC was 0.997 (95%CI [0.990,1.000],P<0.001),sensitivity was 100% and specificity was 98.9%.The same high validity was maintained as in the prediction of cirrhosis (F4 stage) with the cutoff as SWV≥4.50 m/s,and the AUC was 0.993 (95%CI [0.982,1.000],P<0.001),the sensitivity was 100 % and the specificity was 96.8%.Conclusion ARFI elastography is a promising method for differentiating the different severity of NAFLD and staging the degree of hepatic fibrosis with NAFLD in rat models.

6.
Chinese Journal of Medical Instrumentation ; (6): 162-165, 2015.
Article Dans Chinois | WPRIM | ID: wpr-310247

Résumé

Through the study of the pathology of sleep apnea-hypopnea syndrome, evaluation indexes, diagnosis requirements and so on, a portable sleep monitoring system was designed, which had the characteristics of convenience, wireless transmission and no disturbance. The system can be assessed by respiration monitoring and pulse oximetry, which is based on the pressure variation in miniature air-bag and spectral absorption method. It provides the value of the apnea-hypopnea index (AHI), which is used to evaluate OSAHS severity. The experiment of the system's stability and accuracy is done, which exhibits good performance, it can diagnose OSAHS effectively and provide convenience for home monitoring.


Sujets)
Humains , Oxymétrie , Polysomnographie , Syndrome d'apnées obstructives du sommeil , Diagnostic
7.
Journal of Biomedical Engineering ; (6): 914-923, 2015.
Article Dans Chinois | WPRIM | ID: wpr-359547

Résumé

Our country has been using maturity grading method, which was proposed by Grammum in 1979, to evaluate the placental function. However, this method is subjective to consequence because it totally depends on the observation and experiences of clinicians. With the development of ultrasound technology, therefore, we reviewed more novel applications in other aspects of placenta (such as blood flow, vascularization, etc). Over the past years, scholars in the world have done a lot of research around these topics. In this review we introduce placental maturity grading with B-mode ultrasound, placental vascularization qualitative and quantitative analysis with three-dimensional Doppler ultrasound and placental volume measurement, respectively.


Sujets)
Femelle , Humains , Grossesse , Imagerie tridimensionnelle , Néovascularisation pathologique , Placenta , Imagerie diagnostique , Échographie prénatale
8.
Chinese Journal of Medical Instrumentation ; (6): 322-326, 2013.
Article Dans Chinois | WPRIM | ID: wpr-264200

Résumé

Developing an acoustic radiation force excitation module including 64 channels based in FPGA for ultrasound elastography. The circuit of the module was derived in bipolar, and the parameters such as excitation frequency, pulse repetition frequency, pulse number, element number and focus depth were adjustable. The acoustic field for special parameter was experimented with OptiSon laser acoustic field system with a result which reflects the width of focal spot is about 3 mm. The acoustic power was experimented with RFB2000 radiation force balance with a result which reflects acoustic power is increasing linearly with the number of pulses and the number of elements, and is increasing squarely with the peak-to-peak value of excitation voltage. The module is promising in factual application which can be triggered externally in synchronously, and can be combined with B-mode ultrasound system for ultrasound elastography.


Sujets)
Acoustique , Imagerie d'élasticité tissulaire , Science des ultrasons
9.
Chinese Journal of Medical Instrumentation ; (6): 400-406, 2012.
Article Dans Chinois | WPRIM | ID: wpr-342916

Résumé

Based on LCD Module and Visual C++ development environment, this paper proposes a new method which can quickly develop the human-machine interface .We define a LCD module programming interface by designing Serial Communication Class(SCS). On this basis,we achieve the transplantation on an Embedded ARM Platform to fulfil the requirements of Medical Diagnostic Instruments (MDI). Experimental results show that this method has advantages of short development cycle and high level transplantation which has broad application prospects in the field of Medical Diagnosis Instrument.


Sujets)
Diagnostic assisté par ordinateur , Conception d'appareillage , Cristaux liquides , Robotique , Méthodes , Logiciel , Interface utilisateur
10.
Journal of Biomedical Engineering ; (6): 911-915, 2011.
Article Dans Chinois | WPRIM | ID: wpr-359154

Résumé

The dynamic behaviour of a microbubble confined within a rigid micro-tube was studied using finite element method. The results indicated that the microbubble oscillation was limited when constrained within the micro-tube. Both the expansion ratio of its effective radius and natural frequency decreased with the decrease of the tube radius. Meanwhile, the deformation of the microbubble was non-spherical and became more significant when the ultrasound pressure amplitude increased. The dynamic behaviour in micro-tube was different from that in infinite liquid.


Sujets)
Vaisseaux sanguins , Physiologie , Produits de contraste , Analyse des éléments finis , Microbulles , Microtubules , Simulation de dynamique moléculaire
11.
Chinese Journal of Medical Instrumentation ; (6): 369-382, 2011.
Article Dans Chinois | WPRIM | ID: wpr-325979

Résumé

The article introduces the clinical testing method for the product of patient monitor, the definition of direct measurement and indirect measurement method, and the different testing methods. The clinical testing methods for none invasive blood pressure, pulse oxygen saturation and ECG analysis have significant value, which are important solutions to test the safety and effectiveness of medical devices by using the equivalent analysis method. These methods above are also provided as reference for other medical devices' clinical testing.


Sujets)
Humains , Analyse de panne d'appareillage , Sécurité du matériel , Équipement et fournitures , Normes de référence
12.
Chinese Traditional Patent Medicine ; (12): 43-47, 2010.
Article Dans Chinois | WPRIM | ID: wpr-433195

Résumé

AIM: To examine the effect of acrylic ester and thermosol respectively as pressure sensitive adhesive matrix of zhitong huoxue extract ( Rhizoma Corydalis,Radix aconiti,Radix Paeoniae alba,Radix et notoginseng ginseng,etc) on the dissolution of effective constituent from zhitong huoxue extract.METHODS: The in vitro release experiment was carried out on Permcell diffusion cell,HPLC method was applied to determining the cumulative elease rate of tetrahydropalmatine,aconitine,paeoniflorin and ginsenoside Rg_1 from zhitong huoxue pressure sensitive adhensive.RESULTS: The acrylic ester matrix had sound controlled release profile in vitro of alkaloid components.In KT-A thermosol matrix,the in vitro release rate proved to be inversely proportional to the molecular weight (R = 0.91 ) of the effective constituents,while the 2501 s matrix presented a steadily cumulative release rate over 12 h (30% -43% ).CONCLUSION: Good release rates are observed with effective constituent with small molecular weight,adhesive composition of matrix has an obvious effect on the in vitro release behavior of zhitong huoxue extract.

13.
Journal of Pharmaceutical Analysis ; (6): 272-276, 2009.
Article Dans Chinois | WPRIM | ID: wpr-621640

Résumé

Water-fat separation is a particularly important problem for magnetic resonance imaging. Although many methods have been proposed, the reliability is still challenging. In this work, we have presented a method based on the combination of the branch-cut method and multigrid algorithm to get a more robust performance of water-fat separation. First, the branch-cut method is applied to identify residues, which violates the requirement that the interacting phase gradient around a closed path be zero. Residues and branches are marked to be zeros and filled to the weighting factor array. Then, the unwrapped phase array can be given by the multigrid algorithm. Finally, the Dixon method for water-fat separation is applied to the unwrapped phase array. Experiments for brain scanning on the 0.3T low field MRI system demonstrate the successful application of the proposed method.

14.
Chinese Journal of Medical Imaging Technology ; (12): 1289-1292, 2009.
Article Dans Chinois | WPRIM | ID: wpr-472532

Résumé

Objective To develop a recognition method of liver steatosis degree on type-B ultrasonic images based on multi-fractal spectrum texture analysis method and pattern recognition. Methods Features of singularity strength width and multi-spectrum area were extracted from the curve of multi-fractal spectrum of each liver ultrasonic images. These two features and the feature of mean intensity ratio comprised a three-dimensional feature vector, which would be classified by BP neural network. Results The classification accuracy was 96.00% for normal liver, 80.00% for mild fatty liver, 88.00% for moderate fatty liver and 92.00% for severe fatty liver. Conclusion Feature vector combined with BP neural network can identify the steatosis degree of liver on the ultrasonic images and can be used as an assistant diagnostic method.

15.
Journal of Biomedical Engineering ; (6): 510-514, 2008.
Article Dans Chinois | WPRIM | ID: wpr-291201

Résumé

To solve the problem of imprecise positioning of feature point and of the feature data redundancy in facial expression recognition by active appearance models (AAM), the automatic adjustment of initial model for AAM fitting is proposed in this paper. The specific aims are to improve the precision of positioning and to more effectively reflect the variation of expressions by acquired features. The problem of feature selection is resolved by adopting quadratic mutual information and reducing the feature dimension. The support vector machine (SVM) classifier is used for expression recognition. The experimental results on CAS-PEAL facial expression database show that the proposed method effectively improves the performance of facial expression recognition, the maximum recognition rate being 83.33%.


Sujets)
Humains , Algorithmes , Simulation numérique , Expression faciale , Interprétation d'images assistée par ordinateur , Méthodes , Modèles biologiques , Reconnaissance automatique des formes , Méthodes , Traitement du signal assisté par ordinateur
16.
Journal of Biomedical Engineering ; (6): 434-438, 2007.
Article Dans Chinois | WPRIM | ID: wpr-357682

Résumé

Lower contrast and speckle noise are the main reasons which decline the quality of medical ultrasonic images. In this paper, a new method is proposed to filter the speckle noises and enhance the contrast simultaneously. Anisotropic diffusion filtering method was firstly applied to filter images. Then the loss of information, which the contrast function of contrast enhancement model lies on, was obtained. Finally, the contrast can be enhanced by using enhancement model. Experimental results show that the proposed method not only removes the speckle noises effectively, but also enhances the contrast obviously. This method supplies an effective approach for improving the quality of medical ultrasonic images.


Sujets)
Humains , Algorithmes , Anisotropie , Amélioration d'image , Traitement d'image par ordinateur , Méthodes , Traitement du signal assisté par ordinateur , Échographie , Méthodes
17.
Journal of Biomedical Engineering ; (6): 481-484, 2007.
Article Dans Chinois | WPRIM | ID: wpr-357670

Résumé

Speckle is the main reason which declines the quality of medical ultrasonic images. In this paper, the initial condition for the Downhill filter, a morphological reconstruction algorithm, is modified and applied in the speckle reduction. Firstly, the initial area and start position as the mark image was determined in the marker image. Then the modified Downhill filter was used in the ultrasonic marker image. The results showed that, in comparison with the other three filters, this modified Downhill filter, while maintaining the integrity of the contour,could reduce the speckle in the regions of cavity efficiently and rapidly.


Sujets)
Humains , Algorithmes , Amélioration d'image , Méthodes , Traitement d'image par ordinateur , Échographie , Méthodes
18.
Journal of Biomedical Engineering ; (6): 500-512, 2007.
Article Dans Chinois | WPRIM | ID: wpr-357665

Résumé

A method based on a symmetric region growing algorithm is presented for the segmentation of ultrasonic medical image. The method divides into three steps. First, according to the characteristic of the ultrasonic medical images, an adaptive weighted median filter is used to suppress speckle noise. Then, scan the digital image from the first row and grow regions from each scanned point by applying the growth criteria and combination criteria until all image pixels have been scanned. Examine the resulting regions using the seed criteria. If any point of a region satisfies the criteria for the region of interest region, assign the region to the resulting segmented image. The effectiveness of this method and a group of growth criteria as well as combination criteria applicable to ultrasonic medical image have been obtained by cardiac ultrasound image segmentation experiments. The experiment result shows that this method is good in the performance of the segmention of cardiac ultrasonic medical image.


Sujets)
Humains , Algorithmes , Échocardiographie , Méthodes , Amélioration d'image , Méthodes , Traitement d'image par ordinateur
19.
Journal of Biomedical Engineering ; (6): 279-281, 2006.
Article Dans Chinois | WPRIM | ID: wpr-309836

Résumé

Cell culture is one of the usual methods for studying living cell and tissue, the method presented in this paper is based on image processing and analyzing technology for activity estimation of mesenchymal stem cells (MSCs). The existing activity estimation methods are costly, complex and invasive. In this method, thresholding is used to preprocess image and to separate out the growth hallow. Then the area is calculated by counting the pixels of the growth hallow. The changes of the activity estimated by this method are similar to those by corresponding cellular experiments. Compared with the existing methods in biology, medicine or medical cellular science, this method is easier, faster, cost-effective and non-invasive. The proposed method has been proved to be efficient by primary experiments of MSCs.


Sujets)
Animaux , Rats , Cellules cultivées , Fémur , Biologie cellulaire , Traitement d'image par ordinateur , Méthodes , Cellules souches mésenchymateuses , Biologie cellulaire , Rat Sprague-Dawley
20.
Journal of Biomedical Engineering ; (6): 726-729, 2006.
Article Dans Chinois | WPRIM | ID: wpr-320497

Résumé

This study aims to provide a computer-aided method for the diagnosis of fatty liver by B-scan ultrasonic imaging. Fatty liver is referred to the infiltration of triglycerides and other fats of the liver cells, which affected the texture of liver tissue. In this paper, some features including mean intensity ratio, as well as angular second moment, entropy and inverse differential moment of gray level co-occurrence matrix were extracted from B-scan ultrasonic liver images. Feature vectors which indicated two classes of images were created with the four features. Then we used kappa-means clustering algorithm, self-organized feature mapping (SOFM) artificial neural network and back-propagation (BP) artificial neural network to classify these vectors. The accuracy rate of kappa-means clustering algorithm was 100% for normal liver and 63.6% for fatty liver. The results of SOFM neural network showed that the accuracy rate was 84.8% for normal liver and 90.9% for fatty liver. The accuracy rate of neural network was 100% both for normal liver and fatty liver. This technology could detect the characteristics of B-scan images of normal liver and fatty liver more accurately. It could greatly improve the accuracy of the diagnosis of fatty liver.


Sujets)
Humains , Diagnostic différentiel , Stéatose hépatique , Imagerie diagnostique , Traitement d'image par ordinateur , Méthodes , Poumon , Imagerie diagnostique , , Sensibilité et spécificité , Échographie
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