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find Keyword "identification" 27 results
  • ISOLATION, CULTURE, AND IDENTIFICATION OF CANINE UMBILICAL VEIN VASCULAR ENDOTHELIAL CELLS

    Objective To establish a simple and efficient method to isolate and culture the umbilical vein vascular endothelial cells in canine. Methods Twelve umbilical cords [(13.0 ± 1.5) cm in length] were taken from 12 newborn pups of Beagles. And then the vascular endothelial cells were isolated from these umbilical cords digested by 1% collagenase type I for 5, 7, and 10 minutes respectively (4 umbilical cords in each group). After cultured, the vascular endothelial cells were identified by morphology, immunofluorescence, and flow cytometry. And the growth curvature of umbilical vein vascular endothelial cells was detected by MTT assay. Results Few vascular endothelial cells were collected at 5 and 10 minutes after digestion; many vascular endothelial cells were seen at 7 minutes, and became cobblestone with culture time, with a large nucleus; after passage, cell morphology had no obvious change. Fluorescence microscope results showed that positive von Willebrand factor (vWF) and CD31 cells were observed in most of cells. The flow cytometry test displayed that the positive cell rates of vWF and CD31 were 99.0% ± 0.7% and 98.0% ± 1.2%, respectively. The above results indicated that cultured cells were vascular endothelial cells. MTT assay showed that vascular endothelial cells proliferation increased significantly with culture time. Conclusion Enzyme digestion is a convenient method to isolate vascular endothelial cells from canine umbilical vein, and a large number of cells and high purity of cells can be obtained by the method.

    Release date:2016-08-31 04:07 Export PDF Favorites Scan
  • EXPERIMENTAL STUDY ON EFFECT OF MONOCYTE CHEMOATTRACTANT PROTEIN 1 ON MIGRATION OF INDUCED AND DIFFERENTIATED MOUSE BONE MARROW MESENCHYMAL STEM CELLS IN VITRO

    Objective To investigate the effect of monocyte chemoattractant protein 1 (MCP-1) on the migration of the induced and differentiated mouse bone marrow mesenchymal stem cells (BMSCs) for raising the efficacy of intravenous transplantation of BMSCs. Methods The BMSCs were cultured with the method of differential adhesion and density gradient centrifugation of C57/BL10 mice, and were identified by alkal ine phosphatase Gomori modified staining after osteogenic inducing. At the 3rd passage, the BMSCs were induced to the myoblasts with 5-azacytidine (5-Aza). The chemotaxis of MCP-1 in the induced and differentiated BMSCs in vitro at concentrations of 25, 50, 100, 200, and 400 ng/mL was observed through the migration test, by counting the number of the migrated cells. The expression of the chemokine receptor 2 (CKR-2) in the induced and differentiated BMSCs was detected with the flow cytometry. Results The cells could be cultured with the methods of differential adhesion and density gradient centrifugation and still had higher prol iferative and differentiative potency; the induced cells at the 3rd passage could differenciate to the osteoblasts, confirming that the cells were BMSCs; the myogenic induced BMSCs possesed the sarcotubule structure. The number of the migrating BMSCs at MCP-1 concentrations of 25-400 ng/ mL were respectively 35.066 7 ± 6.584 2, 43.200 0 ± 6.460 8, 44.466 7 ± 4.823 5, 45.600 0 ± 8.650 3, and 50.733 3 ± 7.582 5; showing significant difference when compared with control group (28.333 3 ± 8.917 6, P lt; 0.05), and presenting significant difference among 25, 50, 400 ng/mL groups compared with each other (P lt; 0.05). The expression of CKR-2 in the mouse BMSCs (48.0%) was significantly higher (P lt; 0.001) than those of blank control (0.6%) and negative control (17.0%). Conclusion The results indicate that the MCP-1 can induce the migration of mouse BMSCs by MCP-1/CKR-2 pathway.

    Release date:2016-08-31 05:48 Export PDF Favorites Scan
  • Clinical Application of Recurrent Laryngeal Nerve Protection and Monitoring During Thyroidectomy

    Objective To investigate the clinical significance of visual identification and intraoperative neuromonitoring of recurrent laryngeal nerve (RLN) during thyroidectomy. Methods Totally 1 664 patients underwent thyroidectomy with RLN protection from January 2009 to December 2009 were included in this study, in which 1 447 cases were protected by visual identification only, and 217 complex thyroidectomy cases were protected by visual identification and intraoperative monitoring. Results By the “multisites, three steps” RLN exposure method, 1 417 cases (85.16%) were successfully recognized and the recognition time was (3.57±1.26) min. The recognition time in the rest 30 complex cases (2.07%) without intraoperative neuromonitoring was (17.02±5.48) min. By this method, the temporary RLN injury occurred in 23 cases (1.54%) and 15 cases (65.22%) recovered within 2 weeks. In patients undewent intraoperative neuromonitoring, the recognition rate was 100% (217/217) and recognition time was (2.18±0.67) min. The temporary RLN injury occurred in 4 cases (1.84%) and 3 cases (75.00%) recovered within 2 weeks. All temporary RLN injuries recovered within 1 month and no persistent RLN injury occurred. Conclusions Conventional visual identification can reduce the RLN injury, but not meet the needs of the RLN protection during complex thyroidectomy. The combination of visual identification and intraoperative neuromonitoring can further improve the recognition rate and shorten the recovery time of vocal cord dyskinesia.

    Release date:2016-09-08 10:54 Export PDF Favorites Scan
  • A Modeling Method for Human Standing Balance System Based on T-S Fuzzy Identification

    In order to develop safe training intensity and training methods for the passive balance rehabilitation training system, we propose in this paper a mathematical model for human standing balance adjustment based on T-S fuzzy identification method. This model takes the acceleration of a multidimensional motion platform as its inputs, and human joint angles as its outputs. We used the artificial bee colony optimization algorithm to improve fuzzy C-means clustering algorithm, which enhanced the efficiency of the identification for antecedent parameters. Through some experiments, the data of 9 testees were collected, which were used for model training and model results validation. With the mean square error and cross-correlation between the simulation data and measured data, we concluded that the model was accurate and reasonable.

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  • Research on Early Identification of Bipolar Disorder Based on Multi-layer Perceptron Neural Network

    Multi-layer perceptron (MLP) neural network belongs to multi-layer feedforward neural network, and has the ability and characteristics of high intelligence. It can realize the complex nonlinear mapping by its own learning through the network. Bipolar disorder is a serious mental illness with high recurrence rate, high self-harm rate and high suicide rate. Most of the onset of the bipolar disorder starts with depressive episode, which can be easily misdiagnosed as unipolar depression and lead to a delayed treatment so as to influence the prognosis. The early identification of bipolar disorder is of great importance for patients with bipolar disorder. Due to the fact that the process of early identification of bipolar disorder is nonlinear, we in this paper discuss the MLP neural network application in early identification of bipolar disorder. This study covered 250 cases, including 143 cases with recurrent depression and 107 cases with bipolar disorder, and clinical features were statistically analyzed between the two groups. A total of 42 variables with significant differences were screened as the input variables of the neural network. Part of the samples were randomly selected as the learning sample, and the other as the test sample. By choosing different neural network structures, all results of the identification of bipolar disorder were relatively good, which showed that MLP neural network could be used in the early identification of bipolar disorder.

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  • Study of Characteristic Point Identification and Preprocessing Method for Pulse Wave Signals

    Characteristics in pulse wave signals (PWSs) include the information of physiology and pathology of human cardiovascular system. Therefore, identification of characteristic points in PWSs plays a significant role in analyzing human cardiovascular system. Particularly, the characteristic points show personal dependent features and are easy to be affected. Acquiring a signal with high signal-to-noise ratio (SNR) and integrity is fundamentally important to precisely identify the characteristic points. Based on the mathematical morphology theory, we design a combined filter, which can effectively suppress the baseline drift and remove the high-frequency noise simultaneously, to preprocess the PWSs. Furthermore, the characteristic points of the preprocessed signal are extracted according to its position relations with the zero-crossing points of wavelet coefficients of the signal. In addition, the differential method is adopted to calibrate the position offset of characteristic points caused by the wavelet transform. We investigated four typical PWSs reconstructed by three Gaussian functions with tunable parameters. The numerical results suggested that the proposed method could identify the characteristic points of PWSs accurately.

    Release date:2021-06-24 10:16 Export PDF Favorites Scan
  • Arterial Plaques Identification Based on Intravascular Ultrasound Elasticity Imaging

    Intravascular ultrasound (IVUS) is widely used in coronary artery examination. Ultrasonic elastography combined with IVUS is very conspicuous in identifying plaque component and in detecting plaque vulnerability degree. In this study, a simulation model of the blood vessel based on finite element analysis (FEA) was established. The vessel walls generally have radial changes caused by different intravascular pressure. The signals at lower pressures were used as the pre-deformation data and the signals at higher pressure were used as the post-deformation data. Displacement distribution was constructed using the time-domain cross-correlation method, and then strain images. By comparison of elastograms under different pressures, we obtained the optimal pressure step. Furthermore, on the basis of the obtained optimize pressure step, the simulation results showed that this method could effectively distinguish characteristics between different component plaques, and could guide the later experiments and clinical applications.

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  • Extraction, Purification and Identification of a Dexamethasone-degrading Enzymes Generated by Pseudomonas Alcaligenes

    In this research a strain of isolated Pseudomonas alcaligenes which causes degradation of dexamethasone was acclimated further and its proteins of every position in the bacterium were separated by the osmotic shock method. The separated intracellular proteins which had the highest enzyme activity were extracted by the salting out with ammonium sulfate and were purified with the cation exchange chromatography and gel chromatography. The purified proteins which was active to cause degradation of dexamethasone had been detected were cut with enzyme and were analyzed with mass spectrometry. The results showed that the degradation rate to dexamethasone by acclimated Pseudomonas alcaligenes were increased from 23.63% to 52.84%. The degrading enzymes were located mainly in the intracellular of the bacteria and its molecular weight was about 41 kD. The specific activity of the purified degrading enzymes were achieved to 1.02 U·mg-1. Its 5-peptide amino acid sequences were consistent with some sequences of the isovaleryl-CoA dehydrogenase. The protein enzyme may be a new kind degrading enzyme of steroidal compounds. Our experimental results provided new strategies for cleanup of dexamethasone in water environment with microbial bioremediation technique.

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  • A Comparison Study on Early Damage Detection of Left Ventricular Function Based on Doppler Imaging Method for Children with Tumor

    The early damage detection and evaluation are of great significance in treatment and prognosis to the left ventricular function for children with tumor. In this paper, it is reported that the early damage of the left ventricular function was observed by pulsed wave Doppler (PWD) and tissue Doppler imaging (TDI) in our laboratory. Eighty children half a year to fourteen years old were included in this study. The cardiac function indices in chemotherapy group and control group were measured and compared. The results showed that there was significant difference in mitral and tricuspid annulus flow spectrum between the two groups. Compared with PWD, TDI is more prompt, objective and accurate in detecting early damage of left ventricular function in children with tumor.And TDI is a good method for early identification of ventricular function damage in children with tumor.

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  • Research of Left Ventricle Function Analysis Using Real-time Cardiac Magnetic Resonance Imaging

    Real-time free breathing cardiac cine imaging is a reproducible method with shorter acquisition time and without breath-hold for cardiac magnetic resonance imaging. However, the detection of end-diastole and end-systole frames of real-time free breathing cardiac cine imaging for left ventricle function analysis is commonly completed by visual identification, which is time-consuming and laborious. In order to save processing time, we propose a method for semi-automatic identification of end-diastole and end-systole frames. The method fits respiratory motion signal and acquires the expiration phase, end-diastole and end-systole frames by cross correlation coefficient. The procedure successfully worked on ten healthy volunteers and validated by the analysis of left ventricle function compared to the standard breath-hold steady-state free precession cardiac cine imaging without any significant statistical differences. The results demonstrated that the present method could correctly detect end-diastole and end-systole frames. In the future, this technique may be used for rapid left ventricle function analysis in clinic.

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