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Objective: To explore the correlation of left descending anterior (LDA) myocardial bridge (MB) and atherosclerosis at proximal to a segment with MB in patients elderly than 60 years and to identify if LDAMB could become the independent risk factor of atherosclerotic stenosis at proximal to a segment with MB. Methods: A total of 986 patients with multi-slice spiral CT diagnosed coronary artery disease (CAD) were studied and 389 patients with 486 MB in left heart were found. General information as the age, gender, diabetes, hypertension, dyslipidemia and smoking conditions were collected, relationship between LDAMB and atherosclerotic stenosis at proximal to a segment with MB was studied by Logistic regression analysis. Results: There were 48/389 (12.3%) cases with MB at proximal segment of LDA, 254 (65.3%) cases with MB at middle segment of LDA, 51 (13.1%) cases with MB at distal segment of LDA, 19 (4.9%) cases with MB at the ifrst diagonal branch and 17 (4.4%) cases with MB at obtuse marginal branch respectively. Logistic regression analysis presented that age (OR=1.07, 95% CI 0.02-0.09,P0.05. Conclusion: MB at middle segment of LDA was with the higher occurrence rate of atherosclerotic stenosis at proximal to a segment with MB in elderly patients, which could be used as an independence risk factor for clinical diagnosis.
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In the design of oral cone beam CT, cooperation between synergic control of X-ray source, real-time acquisition of flat detector and motion of mechanical structure affects the CT image quality. Based on the full analysis of the flat detector's timing signal characteristics, this research was carried out with microprocessor controller (MCU), complex programmable logic device (CPLD), and light couplings to design and realize synchronous exposure control system. To evaluate whether the design of the synchronous exposure control system in this project could reach the required imaging accuracy, we employed the projected images in the system to analyze its stability, linear consistency, signal to noise ratio and precede the FDK construction.
Subject(s)
Cone-Beam Computed Tomography , Phantoms, Imaging , Radiography, DentalABSTRACT
In order to choose a fast and efficient real-time method in beta wave information extraction, we compared the result and the efficiency of the information separation of both fast Fourier transform (FFT) and wavelet transform of EEG beta band in the present paper. Our work provides the basis for the EEG data come from the real-time health assessment of 3DTV. We took the EEGs of 5 healthy volunteers before, after and during the process of watching 3DTV and meanwhile recorded the results. The trends of the relative energy and the time cost of two methods were compared by using both the FFT and wavelet packet transform (WPT) which was to extract the feature of EEG beta wave. It demonstrated that (1) Results of the two methods were consistent in the trends of watching 3DTV; (2) Results of the differences in two methods were consistent before and after watching 3DTV; (3) FFT took less time than the wavelet transform in the same case. It is concluded that the results of both FFT and Wavelet transform are consistent in feature extraction of EEG, and a fast method to work with the large quantities of EEG data obtained in the experiments can be offered in the future.
Subject(s)
Humans , Male , Young Adult , Algorithms , Brain , Physiology , Electroencephalography , Methods , Fourier Analysis , Signal Processing, Computer-Assisted , Television , Wavelet AnalysisABSTRACT
Objective To evaluate the significance of serum prealbumin, bilirubin/albumin( B/A )ratio and brainstem auditory evoked potential (BAEP)for early predicting the bilirubinic neurotoxicity caused by early neonatal hyperbilirubinemia. Methods According to the gestational age, birth weight and the intervention criterion of neonatal jaundice, 94 neonates (newborn infants with a age of 1-7days) with hyperbilirubinemia were divided into two groups, one was term neonates with normal BAEP, the other was term neonates with abnormal BAEP. We detected their serum levels of total bilirubine, prealbumin, BAEP and calculated B/A ratio. Result The prealbumin levels was significantly lower and B/A ratio was higher in group of abnormal BAEP than those of control group ( P < 0. 01 ), while the levels of total bilirubin were not significantly different between the two groups ( P > 0. 05 ). In group of abnormal BAEP , there was a negative correlation between the level of serum prealbumin and the B/A ratio (r = -0. 637, P <0. 01 ). Conclution Prealbumin may be a sensitive indicator for early predicting bilirubinic toxicity like B/A ratio and BAEP.
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Objective To investigate whether human umbilical vein endothelial cells as a feeder layer was capable of supporting the growth of embryonic stem cells in vitro.Methods Human umbilical vein endothelial cells were isolated and cultured and then prepared as feeder cells after 3 passages.Alkaline posphatase activity(AKP) staining,stem cell surface marker test and karyotypes were conducted in different periods of cell culture.The suspension of stem cells cultured after 20 passages on endothelial cells were inoculated to the legs of severe combined immunodeficiency(SCID) mice subcutabeously to test the teratoma formation.Results E14.1 embryonic stem cells retained good colonies when they were cultured on endothelial cells for 3 passages and 8 passages.In addition,they expressed SSEA-1,Oct-4,and a membrane alkaline phosphatase to a high extent at passages 3 and 8.Embryonic stem cells cultured for 15 passages stably retaind a normal karyotype.Embryonic stem cells cultured on endothelial cells for 20 passages were inoculated into the hind leg of SCID mouse,teratomas containing three embryonic layers were recovered six weeks later.Conclusion Human umbilical vein endothelial cells would support effectively embryonic stem cells expansion,and provide a clinically safe method to expand ES cells for futureclinical application.