Objective: An automatic seamless stitching method with spinal X-ray image sequence is presented in this paper. Methods: First, biorthogonal wavelet transform is used to implement decomposing of the multi-resolution and the effective edge of the image can be extracted by this method combined with Canny operator. The feature points of the image can be obtained by calculating the edge contour matrix E and the value matrix H. Second, the roughly matching of feature points can be achieved by using Normalized Cross Correlation (NCC) algorithm and the random sample consensus (RANSAC) algorithm is introduced to remove false matching pairs and to achieve precisely matching. Third, the image sequence is automatically sorted with the improved genetic algorithm to achieve automatic stitching. At last, the weighted average fusion algorithm is appfied to achieve smooth and seamless image stitching. This algorithm is robust for the weak-contrast X-ray image sequence. Results: Experimental results show that high-quality and fast image sequence stitching can be obtained automatically by using this method. Conclusions: To a certain extent, it overcomes the shortcomings of X-ray image sequence such as the strong image noise, concentration of values ofpixels, blurred boundaries, large overlap area and the sequence constraint, and therefore it may be applied to in medical imaging field widely.

Objective To assess the impact of different number of diffusion gradient directions (NDGD) of diffusion tensor imaging (DTI) on dispersion degree of fractional anisotropy (FA) values and signal-to-noise ratio (SNR) for adult brain tissues. Methods Eight healthy volunteers underwent DTI with 7 NDGD respectively, and the associated FA maps were obtained. Four region of interest (ROI) (genu and splenial of corpus callosum, genu and posterior limb of internal capsule) were chosen in white matter of FA maps, FA values and the corresponding SNRs of the ROIs were computed and analyzed with NDGD increasing. Results FA values within all ROIs did not change remarkably with NDGD increasing. Variance of FA value within two ROIs with high gray value (genu and splenial of corpus callosum) fluctuated randomly and SNR increased slightly, while variance of FA value within the ROIs with low gray value (genu and posterior limb of internal capsule) diminished significantly with NDGD increasing. Conclusion In clinical applications of DTI, an optimum NDGD for DTI data acquisition should be selected according to the ROIs in human brain to be inspected.

Objective To investigate the application of computed radiography(CR) in X-ray projection of whole lower limbs.Methods The radiography in the patient with bilateral knee-malformation was performed using 500 mA X-ray apparatus and several imaging plates(IP) jointed together,then the images including whole both sides of lower limbs were obtained by post-proccesing technique.Results The images not only could show the whole lower limbs on a single film,but be intact.The images also could be used for measuring the length of leg,the angle between the axises of the thigh and the magnifying really.Conclusion The image of whole bilateral lower limbs with a good quality and unity can be acquired using CR and post-processing technique appropriately.

Objective To design an electrostimulator for cerebellar fastigial nucleus stimulus, which is controlled with singlechip system and using EEG(Electroencephalogram)to modulate amplitude of the carrier wave. Methods The EEG with instrumentation amplifier of high CMRR (Common Mode Rejection Ratio) and some filters are collected. The electric insulation is achieved by using linear optocouplers on the parts of input and output. Results The stimulator can solve the problem of adaptability for wave to simulate the body, and is safe, non -invasive, and of obvious therapy for ischemic cerebrovascular disease. Conclusion The cerebellar fastigial nucleus stimulus can cure ischemic cerebrovascular disease obviously, and the modulation with EEG can solve the problem of adaptability for wave to simulate the body.

For the existing measurement methods of residual voltage which can't turn the power off at peak voltage exactly and simultaneously display waveforms, a new residual voltage detection method is put forward in this paper. First, the zero point of the power supply is detected with zero cross detection circuit and is inputted to a single-chip microcomputer in the form of pulse signal. Secend, when the zero point delays to the peak voltage, the single-chip microcomputer sends control signal to power off the relay. At last, the waveform of the residual voltage is displayed on a principal computer or oscilloscope. The experimental results show that the device designed in this paper can turn the power off at peak voltage and is able to accurately display the voltage waveform immediately after power off and the standard deviation of the residual voltage is less than 0.2 V at exactly one second and later.
Electric Power Supplies ; Equipment Design ; Microcomputers ; Signal Processing, Computer-Assisted

ObjectiveTo investigate whether the T1-weighted dynamic contrast-enhanced perfusion magnetic resonance imaging (DCEPMRI) technique can help to delineate the clinical target volume of brain glioma patients.MethodsThe DCE T1-weighted images from 28 glioma patients were collected after GdDTPA was injected.After the acquired images were processed and analyzed using modified Tofts-Kermode'two compartment analysis model and de-convolution method,the value and its pseudo mapping of quantitative parameter Ktrans related to microvascular permeability were obtained.The tumor size in the largest diameter slice measured both in routine enhanced MRI and Ktrans mapping of T1-weighted DCEPMRI were compared.ResultsThe vascular permeability and tumor infiltration was lower in low grade glioma,the difference of the tumor size between T1-weighted DCEPMRI and routine enhanced MRI reached 0.2％ -0.3％ there was significant difference of tumor size between T1 -weighted DCEPMRI and routine enhanced MRI ( grade Ⅰ and Ⅱ grade with 2.93 cm2∶2.46 cm2(t=6.90,P=0.000) and 4.18 cm2∶3.21 cm2(t=10.22,P=0.000) ).While in high grade glioma,the vascular permeability and the tumor infiltration were higher,the difference of the tumor size between T1-weighted DCEPMRI and routine enhanced MRI reached 25％ - 26％( the size of grade Ⅲ and Ⅳ were 6.46 cm2 vs 5.48 cm2 ( t =10.83,P =0.000) and 8.26 cm2 vs 6.52 cm2(t =18.53,P =0.000) ).ConclusionsThe pseudo mapping of quantitative parameter Ktrans related to microvascular permeability acquired by T1-weighted DCEPMRI reflect the infiltrating circumscription in glioma,T1-weighted DCEPMRI can provide more information in delineation the clinical target volume,and it can be used as a new method for tumor volume evaluation.

Objective To investigate the effect of occult HBV infection (OBI) on carcinogenesis of cryptogenic hepatocellular carcinoma.Methods Samples of hepatocellular carcinoma (HCC) and pericarcinomatous tissues obtained after hepatectomy from January 2011 to November 2013 at the Third Affiliated Hospital of Sun Yat-Sen University were collected.They were divided into two groups:the cryptogenic HCC group (the CH group,n =26) and the HBV related HCC group (the HH group,n =40).These samples were compared with the normal liver tissues obtained in 30 patients.HBV DNA was identified by the nested polymerase chain reaction and the immunohistochemical method was taken to examine the hepatitis B virus X protein (HBx) and Yes-associated protein (YAP) expressions.Results OBI was identified in 20 (77.8％) cryptogenic HCC patients and 8 (26.7％) in the control group.There was a significant difference between the two groups (x2 =14.072,P ＜ 0.05).HBV DNA was detected in all the HBV-related HCC patients.The HBx protein expression was mainly located in the cytoplasm of liver cells and liver cancer cells,but YAP was expressed in the nucleus.Both of them showed diffuse brown or tan particles.In the HH group and the CH group,the positive expression rates of HBx protein in the tumorous tissues were 80.0％ and 90.0％,respectively,and 85.0％ and 82.5％ in the nontumorous tissues,but only in 40.0％ in the control group.The positive expression rates of YAP in the tumorous tissues were 65.0％ and 67.5％,respectively,15.0％ and 20.0％ in the nontumorous tissues,respectively,but only in 12.5％ in the control group.The HBx expression in the cancerous tissues and para-cancerous tissues of the HH group and the CH group showed no significant difference (P ＞ 0.05),but the YAP expression in the tumor tissues was significantly higher than that in the nontumorous tissues (P ＜ 0.05).The HBx and YAP expressions in the HH group were comparable to the CH group (P ＞ 0.05).However,their expressions in the cancerous tissue of the HH group and the CH group were significantly higher than in the normal liver tissues (P ＜ 0.05).Conclusion A high prevalence of HBV infection was observed in HBsAg-negative HCC and the high expressions of HBx and YAP might be involved in the process of cryptogenic hepatocellular carcinoma.

Objective To innovate and improve the feasibility of flexible ultrasonic cystoscopy (FUCS) in the diagnosis and treatment for urinary tract diseases in vivo by using female pigs as animal model.Methods Endobronchial ultrasonography was took as a substitute for FUCS and the operating skills and experience of FUCS in vivo by using female pigs as animal model were summarized,in order to testify the efficacy and safety of needle biopsy guided by FUCS.Results FUCS could simultaneously display the endoscopic images and ultrasonic images.Ninety ml was suitable in pig bladder for FUCS when the layers of bladder wall were clear.The mucosa,submucosa,muscularis and serosa layers were legible,which contributed to the needle positioning biopsy.Doppler ultrasound mode could distinguish the vessels,which could guide the puncture and avoid accidental injury of blood vessels and surrounding organs.Pathological results of positioning biopsy were consistent with FUCS evaluation for the three major layers of bladder wall.Conclusion Studies in vivo show that application of FUCS in the diagnosis and treatment for bladder disease is feasible,and further improvement of the FUCS equipment and clinical practice should be made.

Dual-kilovolt technique was realized in dual energy X-ray imaging system with computer controlled KV adjustment, filter switching and image acquirement. The dual energy images can be obtained in 2-3 seconds to avoid moving artifact. Low energy photons in high energy X-ray beam can be attenuated effectively by a 2 mm Cu filter to separate the spectra of the high and low energy X-rays. A simplified dual energy decomposition method was used to obtain the soft tissue image. An example of chest dual energy radiographs is presented to illustrate the performance of the system.
Humans ; Radiography, Dual-Energy Scanned Projection ; methods ; Radiography, Thoracic ; Signal Processing, Computer-Assisted

Objective To investigate the effects of different concentrations of ozone on nigra oxidative stress and apoptosis-related protein expression in rats with Parkinson's disease (PD).Methods Thirty-two adult male SD rats aged 2-3 months and weighted 180-220 g were randomly divided into 4 groups (n=8):PD group,PD+ozone 20 group (given ozone 20 mg/L),PD+ozone 50 group (given ozone 50 mg/L) and control group; rats in the former three groups were given right striatum injection of 15 μg 6-OHDA to induce PD models,and rats in the control group were given the same volume of normal saline; four weeks after PD inducement,mixed gases of 5.0 mL of oxygen and ozone (20 mg/L and 50 mg/L,1 mg/kg) were given to rats in the PD+ozone 20 group and PD+ozone 50 group,respectively,for 15 d.Then,tissues were obtained from nigra; the activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px),and the content of malondialdehyde (MDA) were measured by using chromometry; the protein expressions of B cell lymphoma/lewkmia-2 (Bcl-2) and Bcl-2 associated X protein (Bax) were detected by using Western blotting.Results As compared with those in the control group,the GSH-Px activity was significantly decreased and the MDA content was significantly increased in PD group,PD+ozone 20 group and PD+ozone 50 group (P＜0.05); the GSH-Px activity (6.98±0.60 vs 9.37±0.41、10.04±0.59) was significantly increased and the MDA content(2.31±0.54 vs 1.85±0.29、1.79±0.39) was significantly decreased in PD+ozone 20 group and PD+ozone 50 group as compared with those in the PD group (P＜0.05).Western blotting indicated no significant differences of protein expressions of Bax and Bcl-2 among the four groups (P＞0.05).Conclusion Ozone can improve antioxidation capability of rats with PD by increasing the activity of GSH-PX,while it does not affect the expression levels of Bax and Bcl-2.