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The biocompatibility of HA/TCP ceramic was evaluated by investigation of attachment and growth of osteoblasts on biomaterial, as well as monitoring the effects of biomaterial on expression of functional phenotypes of co-cultured osteoblasts in vitro. When co-cultured with HA/TCP ceramics, osteoblasts firstly attached to the surface of HA/TCP disk, then attached to notches and grew into the micropores of biomaterial during further culture period. At last, the ceramics were almost packed with osteoblasts. Additionally, osteoblasts co-cultured with HA/TCP were similar to osteoblasts cultured under normal condition in osteoblastic phenotypes; the secreted lots of collagen type I, possess strong activity of Alkaline Phosphatase and mineralized extracellular matrix. The fact that osteoblasts could grow well on HA/TCP ceramics and the biomaterial did not affect their physiological function suggest that HA/TCP ceramic is biocompatible with human osteoblasts.

In this paper are reviewed the conceptions, characteristics and application of the complexity measure in studying EEG. The reviewers expound the advantages and problems of using complexity measure in the analysis of EEG in different physiological states and deem it a new way to study and understand the human brain function.

In the language healing system of deaf children, the wavelet transform method is employed to describe the time-varying characteristics of speech signals, improve the resolution of speech spectrum and make the speech characteristics more obvious. The speech spectrum information shown in this system is easier for deaf children to observe and understand and it is of great importance to the language healing of deaf children.

The fractal method is employed to check the voice diseases. The severity of pathological changes of human voice can be analyzed objectively and quantitatively with different fractal dimensions. With this method we can end up the history of judging the voice with subjective hearing and it is of great importance to the development of laryngology.

A new expression for calculating the impulse response of rectangular pistonlike transducers, proper to any points of acoustic field, is presented. The radiated field of ultrasound transducer can be analyzed using impulse response method, avoiding paraxial and farfield approximation. The velocity potential at an observation point is expressed as the convolution of the excitation velocity and the impulse response. A time-amplitude shift method for the far field impulse response of small aperture transducers is presented. The radiated field of rectangular transducers is calculated through the new method and the previous method and excellent agreement is observed.

Based on the texture analysis of B-Scan image fractal model, this paper presents the liver clinical B-Scan images and their fractal characteristics. It describes the semi-fractal characteristics of B-Scan images and calculates the fractal dimension(D) of the liver B-scan images of 10 normal persons, 3 patients with cancer of the liver, and 3 patients with cirrhosis of the liver. The results indicate that Fractal Dimension (D) is an important parameter in differentiating some diseases. On the basis of the influence of Fractal Dimension (D) and scale (epsilon), this paper suggests the texture classified parameter S. The experiment results indicate that the parameter S can be used to differentiate diseases efficiently.

This paper reviews the methods and research advances of recognition and classification of heart sounds. The methods include the statistical techniques and artificial neural network. It also discusses the main problems in the methods.

This paper introduces the present situation of research and methods of multimodality medical images fusion. Some algorithms and relative techniques are given in detail. A summary of the clinical application of multimodality medical images fusion is also presented.

Otoacoustic emissions(OAEs) are presently considered as an objective clinical test for assessing the integraity of peripheral hearing. Owing to the adding of the reflex waves of the stimuli, recordings of emissions evoked in response to transient stimuli are contaminated by an initial artifact, which inhibits the examination of high frequency cochlear responses that have short latencies. So OAEs testing is of serious limitation in most clinical environments. We propose an artifact reduction technique based on discrete wavelet transform pre-processing method and demonstrate empirically that the method not only improves artifact reduction but also enhances signal-to-noise ratio in the response region.

Limited diffraction beams have a large depth of field and thus have many applications such as medical imaging, tissue characterization, material flaw detection and blood flow detection by Doppler method. Nondiffraction beams colud be produced only by transducer with an infinity large aperture in theory. The experimental results show that limited diffraction beams produced by a limited aperture have desirable large depth of field also. The theory of this kind of beams and their applications in field of medical imaging and blood flow estimation are introduced.

In today's image processing researches, image reconstruction is a highlight. It includes the following several aspects: (1) reducing noise before reconstruction or after reconstruction under time-frequency constraints; (2) researches for reconstruction of motion organ; (3) image reconstruction from incomplete projection data; (4) direct volume reconstruction and 3-D image rendering; (5) researches for non-X-ray CT; (6) researches for parallel processing system of CT. In this paper, an introduction to these aspects is given.

Some methods for producing quantitative backscatter images are presented. As a basis, the data reduction method calculates absolute coefficient. The reference phantom method is easier to implement for clinical application. An application method is also presented which separates the contributions of scatter size and scattering strength to backscatter signal and displays Size image and Strength image separately. This method is generally accepted by the medical community. At last, the recent development of ultrasonic backscatter imaging is reviewed.

Because pure titanium is highly reactive at high temperature, its casting surface is easily coated with a thick contaminated layer that affects its physical and chemical properties, and consequently a stable superficial oxide membrane develops in the presence of air or water even at room temperature, which makes the surface discolored. Therefore, surface treatments for pure titanium castings are more important than those for other dental alloy castings. This article reviews the methods of surface treatments for dental titanium castings in four aspects: physical finishing, chemical finishing, electro-chemical finishing and surface modification technology.

Isoparametric element of arbitrary hexahedron plays an important role in finite element analysis. This article devotes itself to establishment of mathematical model and combination of derivative of shape function of such element type. In addition, the article also discusses the usage of isoparametric element for solving 3-D thoracic potential distribution in electrical field.

A new approach to extracting single-trail event-related potential(ERP) in combination with the correlation analysis has been proposed. This approach, called time-frequency filter, is based on the concept that multiresolution wavelet transforms. At first, an investigation of the properties in time and frequency domain was carried out on the ERP. On the basis of the findings, the time-frequency filter of wavelet was designed and used for single-trail ERP extracting. The results and related discussion are presented in this paper.

The Wigner-Ville distribution, the Choi-Williams distribution, and cone-kernel distribution are three time-frequency distributions. We compared the interference attenuation and time-frequency concentration properties of the three TFDs. The properties were then further investigated by studying the results obtained for a chirp signal. We analysed the heart sounds, nonstationary signals, with the three TFDs. The results indicate that the time-frequency signal analysis methods have high time-frequency resolution. The time-frequency signal analysis techniques may be helpful in unveiling the complex mechanisms of heart sound generation and be used in medical research and clinical diagnosis.

This study recorded the event-related potentials (ERP) of eleven healthy male subjects who were in the condition of acute altitude hypoxia caused by in halation of low oxygen mixture. The multiresolution wavelet transform and statistics were used to analyze the ERP. The result demonstrates that the detail components are sensitive to the hypoxia.

Ultrasonic Backscattered Signal(UBSS) from tissues is fundamentally a statistical signal. The statistics of UBSS provide information relating to the number, mean spacing and the scattering cross sections of the scatterers constituting the tissue. Mean scatterer spacing(MSS) is an important parameter for describing the biological tissues microstructural features and tissues ultrasonic scattering characteristics. This paper reviews the methods of MSS estimation as well as ultrasonic imaging based on the scatterer spacing.

In this paper we introduce a method and an implementation of blood flow imaging by means of backscattered Doppler ultrasound power. Compared with Color Flow Map technique based on autocorrelation, this technique is relatively angle independent, aliasing free and more sensitive to blood flow signal with noise background. We present the theory, experimental system and in-vitro experimental results. The realization of this technique means a new stage of color Doppler ultrasound imaging technique in our country is coming.

In this paper, the tri-dimensional computer reconstruction and animated display from serial sections of the genuine crude drug Radix Aconitii have been addressed. Accordingly, some tridimensional image technique and information for the teaching and identification of pharmacognosy have also been offered.

Evoked potentials (EP) is an important bioelectric signal for studying the neural processes, but it is immersed in very strong background noise. Extraction of EP from a single trial has been a topic of great theoretical and clinical interest. In this paper, a new signal processing method--wavelet transform is introduced and several applications are given.

We have investigated the mechanical properties of Chinese aortic and pulmonary valves by means of uniaxial tension. The parameters include the stress-strain curve, the maximum tangent modulus E (the slope of linear segment) in the curve, the tensile strength delta b, and the ultimate strain epsilon b. The results have shown that E, delta b, and epsilon b values between aortic valve and pulmonary valve exist significant differences (significant level = 0.01), but the mechanical property differences between circumferential direction and radial direction in the pulmonary arterial valve are not significant, that means, the valve appears small anisotropic behaviour.