1.Research on fast implementation method of image Gaussian RBF interpolation based on CUDA.
Journal of Biomedical Engineering 2014;31(2):237-244
Image interpolation is often required during medical image processing and analysis. Although interpolation method based on Gaussian radial basis function (GRBF) has high precision, the long calculation time still limits its application in field of image interpolation. To overcome this problem, a method of two-dimensional and three-dimensional medical image GRBF interpolation based on computing unified device architecture (CUDA) is proposed in this paper. According to single instruction multiple threads (SIMT) executive model of CUDA, various optimizing measures such as coalesced access and shared memory are adopted in this study. To eliminate the edge distortion of image interpolation, natural suture algorithm is utilized in overlapping regions while adopting data space strategy of separating 2D images into blocks or dividing 3D images into sub-volumes. Keeping a high interpolation precision, the 2D and 3D medical image GRBF interpolation achieved great acceleration in each basic computing step. The experiments showed that the operative efficiency of image GRBF interpolation based on CUDA platform was obviously improved compared with CPU calculation. The present method is of a considerable reference value in the application field of image interpolation.
Algorithms
;
Image Processing, Computer-Assisted
;
Imaging, Three-Dimensional
;
Normal Distribution
;
Software
2.Statistical approaches for evaluating and dealing with center effects in multi-center clinical trial
Chinese Journal of Clinical Pharmacology and Therapeutics 2004;0(09):-
To search the statistical approaches for evaluating and dealing with the center effects in multi-center clinical trial. Breslow-Day test was used for evaluating the differences of the virtual rating among the centers whose responses were binary, Cochran-Mantel-Haenszel test for dealing with the center effects whose responses were binary or ordinal, and logistic regression for evaluating and dealing with the center effects simultaneously. The results showed that Breslow-Day test is invalid in evaluating the center effects whose response is ordinal, and Cochran-Mantel- Haenszel test can not be used for dealing with the effects of other covariates meanwhile.
3.Research on K-means clustering segmentation method for MRI brain image based on selecting multi-peaks in gray histogram.
Zhaoxue CHEN ; Haizhong YU ; Hao CHEN
Journal of Biomedical Engineering 2013;30(6):1164-1170
To solve the problem of traditional K-means clustering in which initial clustering centers are selected randomly, we proposed a new K-means segmentation algorithm based on robustly selecting 'peaks' standing for White Matter, Gray Matter and Cerebrospinal Fluid in multi-peaks gray histogram of MRI brain image. The new algorithm takes gray value of selected histogram 'peaks' as the initial K-means clustering center and can segment the MRI brain image into three parts of tissue more effectively, accurately, steadily and successfully. Massive experiments have proved that the proposed algorithm can overcome many shortcomings caused by traditional K-means clustering method such as low efficiency, veracity, robustness and time consuming. The histogram 'peak' selecting idea of the proposed segmentootion method is of more universal availability.
Algorithms
;
Brain
;
anatomy & histology
;
Cluster Analysis
;
Humans
;
Magnetic Resonance Imaging
;
Neuroimaging
5.Epidemiology of serum lipid abnormality in patients with coronary artery disease
Hao LIU ; Jinming YU ; Fang CHEN
Chinese Journal of Practical Internal Medicine 2000;0(12):-
Objective To investigate the lipidemia of patients with coronary artery disease(CAD)in China.Methods The survey engaged 52 centers in 7 cities in China recruiting patients with coronary artery disease in a hospital-based setting.Each center was asked to recruit all hospitalized patients with CHD from 1-Jun-2005 to 31-Sep-2005.The study population consisted of 3513 patients with CAD.Results Of the 3513 patients,the prevalence of the lipidemia was 79.7%.And the prevalence of the lipidemia in
6.Moderation effects of justice sensitivity between personality and public mood in volunteers
Zhe YU ; Hao WANG ; Chen CHEN ; Yixin ZHOU ; Mingjie ZHOU
Chinese Journal of Behavioral Medicine and Brain Science 2017;26(1):55-59
Objective To explore the relationship between big-five personality,and public mood of volunteers,and to find out the moderator effect of justice sensitivity.Methods A total of 1 022 volunteers were investigated.The Big-Five Inventory (BFI),Public Mood Scale (PMS),Justice Sensitivity Inventory (JSI) were applied to all subjects.Results The average score was (19.77±4.49) for extraversion,(26.69± 4.13) for agreeableness,(23.33±5.37) for conscientiousness,(12.49±4.91) for neuroticism,(24.95±5.44)for openness,(8.78±3.23) for positive public mood,(3.46±3.06) for negative public mood and correlated with (26.85± 10.55) for observer sensitivity.The extraversion,agreeableness,conscientiousness and openness were correlated with positive public mood(β=0.31,P<0.01;β=0.25,P<0.01;β=0.29,P<0.01;β=0.26,P<0.0 1),and negatively correlated with public mood (β=-0.14,P<0.01;β=-0.29,P<0.01;β=-0.20,P<0.01;β=-0.08,P<0.01).Neuroticism was negatively correlated with positive public mood (β=-0.27,P<0.01),and positively correlated with negative public mood (β=0.31,P<0.01).The interaction effect of agreeableness and observer sensitivity negatively correlated with positive public mood,negative public mood (β=-0.09,P<0.01;β=-0.07,P<0.05).The interaction effect of neuroticism and observer sensitivity was positively correlated with positive public mood (β=0.08,P<0.01).Conclusion Observer sensitivity plays a regulative role between big-five personality and mental health,and can slow the negative impact of low agreeableness to positive public mood,strengthen the impact of low agreeableness to negative public mood,and slow the negative impact of high neuroticism to positive public mood.
7.Diagnostic value of OCT and fundus angiography in patients with high myopia and macular degeneration
Li-Juan, CHEN ; Chen-Yu, HAO ; Jun-Yu, CHEN ; Jing-Xiao, XU
International Eye Science 2016;16(10):1940-1942
AIM: To investigate the significance of optical coherence tomography ( OCT ) and fundus fluorescein angiography ( FFA) in patients with high myopia macular degeneration.
●METHODS:A total of 62 cases ( 104 eyes ) of high myopia macular degeneration patients with OCT and FFA data from Department of Ophthalmology in Jan. 2014 to Sep. 2015 were retrospectively analyzed.
● RESULTS: Highly myopic macular degeneration patients with FFA type, OCT classification had significant correlation (r=0. 599, P<0. 001). Type of OCT in patients with high myopia macular degeneration, with BCVA, diopter, axial length, the thickness at the central fovea measured value difference has statistically significant ( P<0. 05). The higher OCT classification, the lower BCVA, the smaller center of foveal thickness and diopter value and the longer axial length in patients. ln degrees of myopia macular degeneration patients with FFA type, the patients with BCVA, diopter, eye axis length determination of value differences were statistically significant (P<0. 05). Foveal thickness difference of no statistically significant (P>0. 05). The higher FFA type, the smaller ametropia degree, BCVA values, the longer ocular axial length. FFA type patients with foveal thickness determination values were not statistically significant (P>0. 05).
● CONCLUSION: High myopic macular degeneration patients with OCT and FFA results have a certain degree of correlation. However, it′s benefit to combine both of them for further diagnosed and treatment of patients.
8.Relationship of statistics and data management in clinical trials.
Feng CHEN ; Hua-long SUN ; Tong SHEN ; Hao YU
Acta Pharmaceutica Sinica 2015;50(11):1420-1424
A perfect clinical trial must nave a solid study design, strict conduction, complete quality control, non-interference of statistical result, and acceptable risk-benefit ratio. To reach the target, the quality control (QC) should be performed from the study design to conduction, from the analysis to conclusion. We discuss the relationship between data management and biostatistics from the statistical point of view, and emphasize the importance of the statistical concept and methods in the improvement of data quality in clinical data management.
Biostatistics
;
Clinical Trials as Topic
;
statistics & numerical data
;
Data Collection
;
standards
;
Quality Control
;
Research Design
;
standards
9.Usefulness of contrast-enhanced harmonic sonography in renal cell cancer and angiomyolipoma
Yu CHEN ; Yuzhi HAO ; Ning WU ; Qiang ZHU
Chinese Journal of Urology 2009;30(1):40-43
Objective To characterize the image morphology and time-intensity curve of renal cell cancer and angiomyolipoma on contrast-enhanced harmonic sonography. Methods A total of 57 patients with 58 renal masses were enrolled in this study prospectively. The renal masses included 47 renal cell carcinomas (RCC) and 11 angiomyolipomas (AML). All patients were evaluated by tradi-tional gray-scale sonography, color Doppler sonography and contrast-enhanced harmonic sonography. Imaging findings and time-intensity curves of all renal masses were analyzed. The contrast-enhance-ment features between RCC and AML were analyzed. Results 57.4% of RCCs were hyperechoic masses and peripheral surrounding vessels and / or penetrating vessels were noted in 83.0% of RCCs on color Doppler sonography. 54.5 % of AMLs were hyperechoic masses while peripheral surrounding vessels and / or penetrating vessels were only noted in 27.3% of AMLs on color Doppler sonography. On contrast-enhanced harmonic sonography, hyper- or iso-enhancement were noted in 83.0% of RCCs, while hypo-enhancement were noted in 81.8% of AMLs (P<0.01). Statistically significant differences were noted between RCC and AML in the values of peak time (P=0.03), wash time (p= 0.02), peak intensity-basic intensity (P=0. 01), AT/R (△A tumor/△A renal) (P=0.00), k (P= 0.02), and Aok (P=0.02). Conclusions Contrast-enhanced sonography is useful in the differentia-tion of renal masses. Most RCCs are hyper- or iso-enhanced while most AMLs are hypo-enhanced. Time-intensity curves are helpful in differentiating RCC and AML.