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1.
Immobilization using little splint is an original innovation of Chinese people for the fracture fixation, which is simple to use and clinically effective. It was found that Chinese immobilization using little splint can make the non-invasive, uncovering, and trouble free healing of bone fracture via harmonious unity of the structure stability and the force balance, of the motion stability and the stress adaptability, of the constant and discontinuous physiological stress. The biomechanical effect of Chinese immobilization using little splint, including entirety, dynamic, and functional fixity, is the root cause of its inheritance and the use up to now, and also is a direction of today's fracture fixation towards personalization, individuality and entirety.  相似文献   

2.
It is currently difficult for the amputee to perceive environmental information such as tactile pressure on the fingertip of the present upper limb prostheses. Sensory feedback induced by cutaneous electrical stimulation can be used to transmit tactile information from hand prostheses to sensory nerve of intact upper arm, thus producing the corresponding perceptions in human brain. In order to have a deeper understanding on the distribution of stimulation current within the limb, and find a better placement of the stimulating and reference electrodes, we constructed a three-dimensional upper-limb model to systematically study the effect of electrode placement on current distribution based on finite element analysis. In these simulations, the reference electrode is positioned at four different locations around and on the axial direction of the arm. The results show that with the increase of distance between reference electrode and stimulating electrode, the current density increases in the skin layer of the upper limb. When the reference electrode is on the opposite side of stimulating electrode around the arm, the current is more concentrated in the skin layer, which is in line with recent findings in psychophysiological experiments. But better spatial selectivity could be achieved when the reference electrode is closer to the stimulating electrode around the arm, and it is more obvious in comparison with that on the axial direction. These findings will provide insights for the design of electrode array used for evoking cutaneous sensory afferents.  相似文献   

3.
To collect neural activity data from awake, behaving freely animals, we develop miniaturized implantable recording system by the modem chip:Programmable System on Chip (PSoC) and through chronic electrodes in the cortex. With PSoC family member CY8C29466,the system completed operational and instrument amplifiers, filters, timers, AD convertors, and serial communication, etc. The signal processing was dealt with virtual instrument technology. All of these factors can significantly affect the price and development cycle of the project. The result showed that the system was able to record and analyze neural extrocellular discharge generated by neurons continuously for a week or more. This is very useful for the interdisciplinary research of neuroscience and information engineering technique. The circuits and architecture of the devices can be adapted for neurobiology and research with other small animals.  相似文献   

4.
In order to listen to brain activity as a piece of music, we proposed a scale-free brainwave music (SFBM) technology, which translates the scalp EEG into music notes according to the power law of both EEG and music. In this paper, the methodology was further extended to chorus music of two channels from the two hemispheres. Firstly, EEG data from two channels symmetrically located on the left and fight hemispheres are translated into MIDI sequences by SFBM, respectively, where the EEG parameters modulate the pitch, duration and volume of each music note. Then, the two sequences are fiitered into a chorus of the Chinese pentatonic scale or the Western major scale. The resulted Chinese and Western music at different sleep stages illustrate distinct differences in harmony, and the music with Chinese pentatonic scale sounds more harmonious.  相似文献   

5.
Objective:To investigate the influence of different right ventricular (RV) pacing sites on QRS width, and to provide a potential reference site for permanent right ventricular pacing in patients implanted with permanent pacemakers. Pacing at the site with the shortest QRS duration may reduce the deleterious effects of RV pacing on LV function, and thus having beneficial effects on patient's outcome. Methods: All consecutive patients who were planned to have permanent pacemaker implantation for a ClassI or IIaindication atour departmentfromOctober 2010 toJuly2012 werescreened for the participation in this prospective, single center, non-randomized study. The baseline surface ECG was analyzed for QRS width and morphology, respectively. During the implantation procedure patients were transiently paced at different RV locations(right ventricular apex, right ventricular inflow tract [RVIT], mid septum, high septum and right ventricular outflow tract [RVOT]) before the lead was placed at its final position. During pacing at the different positions the surface 12-leads ECG was recorded. Based on the surface of ECG QRS duration and morphology of the different right ventricular pacing sites were analyzed and compared with baseline and to each other. Results: A total of 216 patients(39% female, mean age 69±13 years, higher degreeAV block 30.5%)wasenrolled in thestudy. Paced QRS duration wassignificantly different between all right ventricular pacing sites compared with the baseline ECG(baseline: 106 ms±21 ms; mean paced: 158 ms±16 ms; p0.001). RVA pacing showed the widest QRS(168 ms±16 ms). QRS duration with RVIT pacing was 166 ms±15 ms,and that with RVOT pacing was 165 ms±15 ms, respectively. QRS duration was not significantly different between these three positions. Mid-septal pacing showed the narrowest QRS(139 ms±19 ms) compared to all other pacing sites(p0.001). Pacing at the high-septum showed a broader QRS (153 ms±14 ms) than that pacing at the mid-septum. Compared to other right ventricular pacing sites, QRS morphology at the mid-septum was close to normal, and electrical axis was unchanged as compared to baseline. Conclusion: Pacing at different right ventricular sites showed the significant widening of QRS compared to baseline. The shortest QRS duration was seen with mid-septal pacing. Therefore, mid-septal pacing may have less deleterious effect on LV function compared to other RV pacing locations, which may be the optimal right ventricular pacingsite in permanent pacemaker recipients.  相似文献   

6.
The dielectric properties in vitro present characteristic changes along with the alteration of metabolic activities, which can be detected from tissue micro- structure. The dielectric properties of tissues are closely related to its viability, but the relationship remains unclear to us. This study aims to specify the relationship between dielectric parameters and microstructure of living tissues and to try to explain the influence of tissue viability on dielectric properties. Nine rabbits were studied in this experiment. The impedance spectroscopy (10 Hz-1 MHz) and microstructure were determined at different time intervals (from 5 rain to 7 h) after samples were prepared. Some characteristic parameters were extracted to analyze the relationship between them. The inactivation process characterized by the mierostrueturs could be detected by means of dielectric parameters: the microstructures had no obvious change within 30 rain a.nd cell swelling caused by osmosis led to the decrease of extracellular ion concentration, resulting in the rise of lowfrequency impedance after 30 rain. The reduction of impedance was accompanied by the expanding intercellular area and irregular cell shape caused by the gradual destruction of cell membrane.The functions between alteration rate of intercellular area and Cole-Cole model parameters were also established. There is a strong correlative relationship between dielectric properties and microstructure. The dielectric spectrum can be a rapid and innocuous method to monitor the status of tissues. In the future, it may be of great help for clinical application, especially in transplantation.  相似文献   

7.
This paper reports some experimental detecting results of pollutants in the atmosphere by means of laser mass spectrometry. For toluene as calibration gas, the calibration procedure was also given. Benzene, toluene and xylene were discovered in testing indoor atmosphere resulting from dope in the course of fitment. Meanwhile, it is noticeable that the concentration of various harmful elements is obviously decreasing as time goes on.  相似文献   

8.
The aim of this study is to estimate the chaos phenomenon in temporomandibular joints (TMJ) sound using fractal dimension (FD), and to examine the diagnostic value of the FD in comparing TMJ sounds produced by 6 asymptomatic and 25 symptomatic TMJ. Multiple mandibular opening and closing cycles recorded were used to calculate the waveform dimension and correlation dimension in the FD. Chaos in the TMJ sounds was estimated by the FD that was saturated with some constant value to an increase of embed- ding dimension. Results reveal that fractal analysis produces a high degree of reproducibility within, and similarity across subjects, and indicate that both FD values of the asymptomatic TMJ sounds are significantly higher than those of the symptomatic. These findings suggest that chaos is present in TMJ sounds and the difference in the FD is of diagnostic value in evaluation of pathological change in TMJ sound signals.  相似文献   

9.
In the present study we prepared macroporous polyvinyl alcohol beads. A series of bilirubin adsorbents were generated by immobilization of eight amine agents to the beads as ligands. The adsorption of bilirubin was evaluated by in vitro static and dynamic adsorption tests. The results show that these adsorbents have excellent adsorption efficiency and capacity. Among the eight ligands, trimethylamine (TMA), triethylamine (TEA) and 1,6- hexanediamine (HDA) showed the highest adsorption capacity. The adsorption equilibrium can be achieved in half an hour, and the adsorption percentage of bilirubin was up to 80%. Static electricity and hydrophobie interaction played the main role in bilirubin adsorption, and the adsorption was found to match the monolayer model. The excellent adsorption of these adsorbents indicates their potential in clinical treatment.  相似文献   

10.
This paper presents the knee-joint vibration signal processing and pathological localization procedures using the empirical mode decomposition for patients with chondromalacia patellae. The artifacts of baseline wander and random noise were identified in the decomposed monotonic trend and intrinsic mode functions (IMF) using the modeling method of probability density function and the confidence limit criterion. Then, the fluctuation parts in the signal were detected by the signal method turning for count. The results demonstrated that the quality of reconstructed signal can be greatly improved, with the removal of the baseline wander (adaptive trend) and the Gaussian distributed random noise. By detecting the turn signals in the artifact-free signal, the pathological segments related to chondromalacia patellae can be effectively localized with the beginning and ending points of the span of turn signals.  相似文献   

11.
This research uses alginate and hyaluronic acid as the main component to prepare support, then explores the possibilities as a tissue engineering scaffold. Firstly, prepare HA with various average molecular weight and alginate with different viscosity, mix them up at a certain proportion and make it into a AlgCa2 +-HA composite scaffold with a film-forming method. This article discusses the feasibility of this scaffold used in tissue engineering field according to the consequence of moisture content testing, mechanical analysis, and scanning electron microscopy analysis. The structure and properties of AlgCa2 +-HA composite scaffold are closely related to some factors such as average molecular weight of hyaluronic acid, hyaluronic acid concentration, alginate viscosity, cross-linking agents and processing technology. The AlgCa2+-HA composite material, which is at different proportions and adding different cross-linking agent,has some certain characteristics: moisture content ranging from 50% to 95%, tensile strength between 2.69 N/mm2 and 4.299 N/mm2, and elongation at break is about 58% to 160%. The prepared AlgCa2+-HA composite scaffolds can be used as tissue engineering scaffolds resulting from its high moisture content, good mechanical properties and ideal pore structure.  相似文献   

12.
Continuous estimation of wrist torque from surface electromyography (EMG) signals has been studied by some research institutes. Hysteresis effect is a phenomenon in EMG force relationship. In this work, a path-dependent model based on hysteresis effect was used for continuously estimating wrist torque from surface EMG signals. The surface EMG signals of the flexor carpi ulnaris (FCU) and extensor carpi radialis (ECR) were collected along with wrist torque of flexion/extension degree-of-freedom. EMG signal of FCU was used to estimate the torque of wrist flexion and EMG signal of ECR to estimate the torque of wrist extension. The existence of hysteresis effect has been proven either during wrist flexion or extension on all subjects. And the estimation performance of path-dependent model is much better than the overall model. Thus, the path-dependent model is suitable to improve the wrist torque's estimation accuracy.  相似文献   

13.
Objective: This study aims to explore the association between the density of Himalayan marmot (Marmota himalayana) and climatic factors such as temperature, precipitation, humidity, vapour pressure, sunshine percentage, wind velocity, which are closely associated with global climate change, and to provide a reference for plague prevention and control. Methods: We conducted a regression analysis to find the possible climate factors associated with the density of Himalaya marmot, and analyzed the response characters of Himalayan marmot to climate change. Results: Daily precipitation days (〉=0.1 mm) and sunshine percentage were significantly associated with the density of Himalayan marmot (P〈0.01). Conclusion: Climate change was associated with the risk of plague. This phenomenon is valuable for Himalayan marmot and plague prevention. More studies are needed to understand the impact of climate change on Himalayan marmot and plague.  相似文献   

14.
A wearable body area sensor network (WBASN) was designed and implemented to monitor movement information of stroke patients in real time. The sensor system was combined with a previously developed distributed functional electrical stimulation (dFES) system, which is a promising technology for motor rehabilitation of stroke patients. Movement information could be useful in outcome assessment of rehabilitation, or for closed-loop adaptive stimulation during rehabilitation. In addition, a short-latency, low-power communication protocol was developed to meet the clinical requirements of energy efficiency and high rate of data feed-through. The prototype of the WBASN was tested in preliminary human experiments. Experimental results demonstrate the feasibility of the proposed wearable body area sensor network in monitoring arm movements on healthy subjects.  相似文献   

15.
Agonistic AT1 receptor autoantibodies (AT1-AAs) have been described in the patients with malignant hypertension or preeclampia. Furthermore, AT1-AAs were highly associated with refractory hypertension. Function of vascular smooth muscle cells (VSMCs) is important in the regulation of blood pressure. We investigated and compared the ability of angiotensin II (Ang II) and AT1-AAs to stimulate the intracellular calcium mobilization and cellular proliferation of rat VSMCs. Twenty-two patients with refractory hypertension, 24 patients with non-refractory hypertension and 37 normotensives were recruited. The serum of each patient was detected for the presence of AT1-AAs by ELISA. Ang II and the AT1-AAs from the sera of patients were used to stimulate rat VSMCs in vitro. AT1-AAs were detected in 10/22, 3/24 and 3/37 of patients with refractory hypertension, non-refractory hypertension and normotensives, respectively. AT1-AAs led the increase intracellular calcium mobilization in a dose-dependent manner and cellular proliferation of VSMCs just as Ang II. Both of these effects caused by AT1-AAs were blocked with losartan or a peptide corresponding to a part of the second extracellular loop of AT1 receptor. Since AT1-AAs exhibited pharmacological activity in rat VSMCs just as Ang II, they might play a role in the elevation of peripheral vascular resistance and in vascular remodeling. And AT1-AAs were suggested to involve in resistance to antihypertensive therapy.  相似文献   

16.
This paper aims to meet the requirements of reducing the scanning time of magnetic resonance imaging (MRI), accelerating MRI and reconstructing a high quality image from less acquisition data as much as possible. MRI method based on compressed sensing (CS) with multiple regularizations (two regularizations including total variation (TV) norm and L1 norm or three regularizations consisting of total variation, L1 norm and wavelet tree structure) is proposed in this paper, which is implemented by applying split augmented lagrangian shrinkage algorithm (SALSA). To solve magnetic resonance image reconstruction problems with linear combinations of total variation and L1 norm, we utilized composite spht denoising (CSD) to split the original complex problem into TV norm and L1 norm regularization subproblems which were simple and easy to be solved respectively in this paper. The reconstructed image was obtained from the weighted average of solutions from two subprohlems in an iterative framework. Because each of the splitted subproblems can be regarded as MRI model based on CS with single regularization, and for solving the kind of model, split augmented lagrange algorithm has advantage over existing fast algorithm such as fast iterative shrinkage thresholding(FIST) and two step iterative shrinkage thresholding (TWIST) in convergence speed. Therefore, we proposed to adopt SALSA to solve the subproblems. Moreover, in order to solve magnetic resonance image reconstruction problems with linear combinations of total variation, L1 norm and wavelet tree structure, we can split the original problem into three subproblems in the same manner, which can be processed by existing iteration scheme. A great deal of experimental results show that the proposed methods can effectively reconstruct the original image. Compared with existing algorithms such as TVCMRI, RecPF, CSA, FCSA and WaTMRI, the proposed methods have greatly improved the quality of the reconstructed images and have better visual effect.  相似文献   

17.
A new wavelet variance analysis method based on window function is proposed to i, nvestigate the dynamical features of electroencephalogram (EEG).The ex- prienmental results show that the wavelet energy of epileptic EEGs are more discrete than normal EEGs, and the variation of wavelet variance is different between epileptic and normal EEGs with the increase of time-window width. Furthermore, it is found that the wavelet subband entropy (WSE) of the epileptic EEGs are lower than the normal EEGs  相似文献   

18.
This paper introduces a middleware design and implementation for an infant protection system-maternal infant safety and surveillance (MISS), using radio-frequency identification (RFID) technology. The middleware is located between application level and hardware-device level in the hierarchical software structure, which is in further divided into three levels, i.e. data, logical and service respectively. The rationale for the design is based on the consideration of the performance, organization, maintenance, and upgrade factors.  相似文献   

19.
Using both the wavelet decomposition and the phase space embedding, the phase trajectories of electroencephalogram (EEG) is described. It is illustrated based on the present work, that is, the wavelet decomposition of EEG is essentially a projection of EEG chaotic attractor onto the wavelet space opened by wavelet filter vectors, which is in correspondence with the phase space embedding of the same EEG. In other words, wavelet decomposition and phase space embedding are equivalent in methodology. Our experimental results show that in both the wavelet space and the embedded space the structure of phase trajectory of EEG is similar to each other. These results demonstrate that wavelet decomposition is effective on characterizing EEG time series.  相似文献   

20.
In this study, we compared two types of EEG modalities, sensory-motor rhythms (SMR) and movement related cortical potentials (MRCP), on four healthy subjects performing ballistic or repetitive movement imagination. The EEG waveform morphology across subjects was similar for MRCPs, whereas there was not a clear pattern for SMRs. The rank-sum test showed a significant difference between the amplitude of baseline and that of the MRCP as early as 2 s prior to imagery onset, for both types of motor imageries, indicating strong discriminative power of MRCPs for predicting movement onset. For SMR, this type of discriminative power was relatively weak and highly subject-specific. On the other hand, the SMR landscape under the two movement imagery types was distinctive, holding a potential for discriminating the two movement imagery types. These preliminary results presented different characteristics of SMR and MRCP under different motor imageries, providing valuable information regarding the design and implementation of motor imagery based on BCI system.  相似文献   

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