west china medical publishers
Keyword
  • Title
  • Author
  • Keyword
  • Abstract
Advance search
Advance search

Search

find Keyword "detection" 94 results
  • Detection of Multiple Gene Mutations in Stool for Secondary Screening for Colorectal Cancer

    Objective To evaluate the possibility of detection mutations of 〖JP2〗multiple genes in stool for secondary screening for colorectal cancer. Methods Tumor specimens and stool samples from 40 patients with colorectal cancer and 40 normal persons were examined for mutations of p53, K-ras and APC gene by polymerase chain reaction single strand conformation polymorphism (PCR-SSCP) and silver nitrate staining. Results ①The mutation rate of p53, K-ras and APC gene in the tissues and stools of colorectal cancer respectively were 57.50%, 50.00%, 60.00% and 42.86%, 40.00%, 51.43%, and no mutations were found in normal mucosa and stool. ②The mutation ratioes between multiple gene and single gene had significant difference (P<0.05). ③The sensitivities had no significant difference between faecal occult blood test (FOBT) and multiple gene mutations detection in the diagnosis of colorectal cancer, but the specificity of the latter was higher than FOBT (P<0.05). Conclusion  Detection of multiple gene mutations in stool is a vauble method in the secondary screening for colorectal cancer.

    Release date:2016-08-28 04:08 Export PDF Favorites Scan
  • EFFECT OF BMSCs TRANSPLANTATION ON CARDIAC FUNCTION OF DIABETES MELLITUS RATS

    Objective To observe the effect of BMSCs on the cardiac function in diabetes mellitus (DM) rats through injecting BMSCs into the ventricular wall of the diabetic rats and investigate its mechanism. Methods BMSCs isolated from male SD rats (3-4 months old) were cultured in vitro, and the cells at passage 5 underwent DAPI label ing. Thirty clean grade SD inbred strain male rats weighing about 250 g were randomized into the normal control group (group A), the DM group (group B), and the cell transplantation group (group C). The rats in groups B and C received high fat forage for 4 weeks and the intraperitoneal injection of 30 mg/kg streptozotocin to made the experimental model of type II DM. PBS and DAPI-labeledpassage 5 BMSCs (1 × 105/μL, 160 μL) were injected into the ventricular wall of the rats in groups B and C, respectively. After feeding those rats with high fat forage for another 8 weeks, the apoptosis of myocardial cells was detected by TUNEL, the cardiac function was evaluated with multi-channel physiology recorder, the myocardium APPL1 protein expression was detected by Western blot and immunohistochemistry test, and the NO content was detected by nitrate reductase method. Group C underwent all those tests 16 weeks after taking basic forage. Results In group A, the apoptosis rate was 6.14% ± 0.02%, the AAPL1 level was 2.79 ± 0.32, left ventricular -dP/dt (LV-dP/dt) was (613.27 ± 125.36) mm Hg/s (1 mm Hg=0.133 kPa), the left ventricular end-diastol ic pressure (LVEDP) was (10.06 ± 3.24) mm Hg, and the NO content was (91.54 ± 6.15) nmol/mL. In group B, the apoptosis rate was 45.71% ± 0.04%, the AAPL1 level 1.08 ± 0.24 decreased significantly when compared with group A, the LVdP/ dt was (437.58 ± 117.58) mm Hg/s, the LVEDP was (17.89 ± 2.35) mm Hg, and the NO content was (38.91±8.67) nmol/mL. In group C, the apoptosis rate was 27.43% ± 0.03%, the APPL1 expression level was 2.03 ± 0.22, the LV -dP/dt was (559.38 ± 97.37) mm Hg/ s, the LVEDP was (12.55 ± 2.87) mm Hg, and the NO content was (138.79 ± 7.23) nmol/ mL. For the above mentioned parameters, there was significant difference between group A and group B (P lt; 0.05), and between group B and group C (P lt; 0.05). Conclusion BMSCs transplantation can improve the cardiac function of diabetic rats. Its possible mechanismmay be related to the activation of APPL1 signaling pathway and the increase of NO content.

    Release date:2016-09-01 09:08 Export PDF Favorites Scan
  • Diagnosis of Arteriosclerosis Obliterans of Lower Extremity in Early Stage

    Objective To explore the methods of early diagnosis of arteriosclerosis obliterans of lower extremity (ASOLE). Methods The related literatures on ASOLE detection means adopted clinically were reviewed, and their advantages and disadvantages were compared.Results Asymptomatic ASOLE could be discovered by determination of ankle brachial index (ABI) and toe brachial index (TBI), which was a good index for arterial function assessment of lower extremity. Pulse wave velocity (PWV) was more vulnerable and less sensitive than ABI, and therefore more suitable for screening of a large sample. ASI was an index to assess arterial structure and function, and it had a good correlation with PWV. Flow-mediated dilation (FMD) was a measurement evaluating the function of endothelial cell; Pulse wave measurement was simple, sensitive, and its result was reliable. Color Doppler ultrasonography could localizate the lesion and determine the degree of stenosis at the same time. Multiple-slice CT angiography (MSCTA) was more accurate than color Doppler ultrasonography, but its inherent shortcomings, such as nephrotoxicity of contrast agent, was still need to be resolved. 3D-contrast enhancement magnetic resonance angiography (CEMRA) had little nephrotoxicity, but a combination of other imaging methods was necessary. Microcirculation detections required high consistency of the measurement environment, but they were simple, sensitive and noninvasive, and therefore could be used for screening of ASO. Conclusion Publicity and education of highrisk groups, and reasonable selection of all kinds of detection means, are helpful to improve the early diagnosis of ASOLE.

    Release date:2016-09-08 10:54 Export PDF Favorites Scan
  • Clinical Application of Combined Detection of Serum Carbohydrate Antigen 199, Alanine Aminotransferase, and Gamma-glutamyl Transferase in the Diagnosis of Hyperthyroid Liver Damage

    ObjectiveTo investigate the significance of carbohydrate antigen 199 (CA199), alanine aminotransferase (ALT), gamma-glutamyl transferase (γ-GT) levels in the diagnosis of liver damage caused by hyperthyroidism. MethodA total of 106 patients confirmed to have hyperthyroid liver damage between February 2012 and February 2014 were selected to form the hyperthyroidism liver injury group (group A). Ninety-five hyperthyroidism patients without liver damage were regarded as the hyperthyroidism without liver injury group (group B). In the same period, 72 healthy subjects were designated to form the control group (group C). Automatic chemiluminescence detector was used to determine free triiodothyronine, free thyroid hormone and CA199, and automatic biochemical analyzer was adopted to measure the levels of γ-GT and ALT. Then we performed the statistical analysis. ResultsThe levels of serum CA199, γ-GT and ALT in group A were significantly higher than those in group B and group C, and the differences were statistically significant (P<0.05). CA199 and γ-GT levels in group B were significantly higher than those in group C (P<0.05). The area under the receiver operating characteristic curve for CA199, γ-GT, ALT was respectively 0.840, 0.895, and 0.818, the maximum Youden indexes were 0.593, 0.703, and 0.578, with the corresponding critical values 37.25 U/mL, 60.81 U/L, and 43.14 U/L, respectively. The parallel dectection of the three indexes improved Youden index to 0.763. ConclusionsCA199, γ-GT and ALT as diagnosis indexes of hyperthyroidism liver damage have good diagnostic value, and combined detection of the three indexes is more favorable for early diagnosis and prediction.

    Release date: Export PDF Favorites Scan
  • A P-wave Detection Method Based on Multi-feature

    Generally, P-wave is the wave of low-frequency and low-amplitude, and it could be affected by baseline drift, electromyography (EMG) interference and other noises easily. Not every heart beat contains the P-wave, and it is also a major problem to determine the P-wave exist or not in a heart beat. In order to solve the limitation of suiting the diverse morphological P-wave using wavelet-amplitude-transform algorithm and the limitation of selecting the pseudo-P-wave sample using the wavelet transform and neural network, we presented new P-wave detecting method based on wave-amplitude threshold and using the multi-feature as the input of neural networks. Firstly, we removed the noise of ECG through the wavelet transform, then determined the position of the candidate P-wave by calculating modulus maxima of the wavelet transform, and then determine the P-wave exist or not by wave-amplitude threshold method initially. Finally we determined whether the P-wave existed or not by the neural networks. The method is validated based on the QT database which is supplied with manual labels made by physicians. We compared the detection effect of ECG P-waves, which was obtained with the method developed in the study, with the algorithm of wavelet threshold value and the method based on "wavelet-amplitude-slope", and verified the feasibility of the proposed algorithm. The detected ECG signal, which is recorded in the hospital ECG division, was consistent with the doctor's labels. Furthermore, after detecting the 13 sets of ECG which were 15min long, the detection rate for the correct P-wave is 99.911%.

    Release date: Export PDF Favorites Scan
  • A Quantitative Detection of Poincare Scatter for T-wave Alternans

    To study the quantitative detection method of T-wave alternans (TWA), we analyzed the relationship between the graphic mode of Poincare scatter and TWA, and proposed ‘horizontal search algorithm' to complete graphic processing. Then, based on the shape of Poincare scatter, we took Axial_ratio as the final index. Through Matlab simulation, Axial_ratio was compared with the results of spectral method (SM) and appropriate threshold value was selected to recognize the TWA. The results showed that Axial_ratio could accurately detect the TWA.

    Release date: Export PDF Favorites Scan
  • Medical Image Processing Based on Wavelet Characteristics and Edge Blur Detection

    To solve the problems of noise interference and edge signal weakness for the existing medical image, we used two-dimensional wavelet transform to process medical images. Combined the directivity of the image edges and the correlation of the wavelet coefficients, we proposed a medical image processing algorithm based on wavelet characteristics and edge blur detection. This algorithm improved noise reduction capabilities and the edge effect due to wavelet transformation and edge blur detection. The experimental results showed that directional correlation improved edge based on wavelet transform fuzzy algorithm could effectively reduce the noise signal in the medical image and save the image edge signal. It has the advantage of the high-definition and de-noising ability.

    Release date: Export PDF Favorites Scan
  • A Review on the Research Progress of the Computer-Aided Detection of Pulmonary Nodule

    Computer-aided detection (CAD) of pulmonary nodule technology can effectively assist the radiologist to enhance lung nodule detection efficiency and accuracy rate, so it can lay the foundation for the early diagnosis of lung cancer. In order to provide reference for the scholars and to develop the CAD technology, we in this paper review the technology research and development of CAD of the pulmonary nodules which is based on CT image in recent years both home and abroad. At the same time, we also analyse the advantages and shortcomings of different methods. Then we present the improvement direction for reference. According to the literature in recent years, there still has been large development space in CAD technology for pulmonary nodules. The establishment and improvement of the CAD system in each step would be of great scientific value.

    Release date: Export PDF Favorites Scan
  • Technical Research of Non-contact Electrocardiogram Based on Capacitive Coupling

    Based on the capacitance coupling principle, we studied a capacitive way of non-contact electrocardiogram (ECG) monitoring, making it possible to obtain ECG on the condition that a patient is habilimented. Conductive fabric with a good electrical conductivity was used as electrodes. The electrodes fixed on a bed sheet is presented in this paper. A capacitance comes into being as long as the body gets close to the surface of electrode, sandwiching the cotton cushion, which acts as dielectric. The surface potential generated by heart is coupled to electrodes through the capacitance. After being processed, the signal is suitable for monitoring. The test results show that 93.5% of R wave could be detected for 9 volunteers and ECG with good signal quality could be acquired for 2 burnt patients. Non-contact ECG is harmless to skin, and it has advantages for those patients to whom stickup electrodes are not suitable. On the other hand, it is convenient to use and good for permanent monitoring.

    Release date: Export PDF Favorites Scan
  • Anomaly Detection of Multivariate Time Series Based on Riemannian Manifolds

    Multivariate time series problems widely exist in production and life in the society. Anomaly detection has provided people with a lot of valuable information in financial, hydrological, meteorological fields, and the research areas of earthquake, video surveillance, medicine and others. In order to quickly and efficiently find exceptions in time sequence so that it can be presented in front of people in an intuitive way, we in this study combined the Riemannian manifold with statistical process control charts, based on sliding window, with a description of the covariance matrix as the time sequence, to achieve the multivariate time series of anomaly detection and its visualization. We made MA analog data flow and abnormal electrocardiogram data from MIT-BIH as experimental objects, and verified the anomaly detection method. The results showed that the method was reasonable and effective.

    Release date: Export PDF Favorites Scan
10 pages Previous 1 2 3 ... 10 Next

Format

Content