This paper presents a new kind of collecting and processing system of the sound signal of larynx where double sound cards and software filter are used. The installation of the double sound cards and processing proposal of software are mainly discussed and a new kind of ADC method of dual-channel sound signal is put forward in this paper. This system has the feature of reliable performance, simple installation and easy maintenance.
Algorithms ; Equipment Design ; Humans ; Larynx ; physiology ; Microcomputers ; Signal Processing, Computer-Assisted ; instrumentation ; Software ; Sound ; Speech Production Measurement ; instrumentation

This paper introduces the application of H7279intelligent display chip to the selection and display of different kinds of analog electrocardiogram output by the analog electrocardiogram generator controlled by a single chip micyoco(SCM).

In this study, ECG signals of normal sinus rhythm (NSR), ventricular tachycardia (VT) and ventricular fibrillation (VF) were taken out to extract the RR interval series. Approximate entropy (ApEn) values of the RR interval series were calculated and compared among the three groups by ANOVA methods. It was found that the values of ApEn were increased significantly from NSR to VT and then to VF. Approximate entropy may be regarded as an index to discriminate the ECG signals of different state.
Electrocardiography ; methods ; Entropy ; Humans ; Signal Processing, Computer-Assisted

Objective To definite the status of tone of autonomic nervous system during water immersion process by analyzing the nonlinear characteristic of ECG signals;To explore the relation of approximate entropy(ApEn),scaling exponent(?) changes and modulation function status of autonomic nervous system.Methods The ECG signals of rats during the process of restraint stress(RS),water-immersion restraint stress(WRS) and Vagotomy and Water-immersion restraint stress(vagotomy-WRS) were recorded.The ApEn and ? of RR intervals were calculated.Results After the stress,the differences of the value of ApEn and ? of RR intervals between RS and vagotomy-WRS groups and between different periods in vagotomy-WRS group were not significant.The value of ApEn increased in WRS group and decreased in RS group significantly.Compared with pre-stress,? showed decreased trend,all of the values smaller than 0.5 in WRS group and increased obviously,most values larger than 0.5 in RS group.Conclusion The increased ApEn and decreased ? indicates a higher intensity of parasympathetic activity.The parasympathetic activity is the predominant response of autonomic nervous system during water immersion process.

Chaos and fractals are ubiquitous phenomena of nature. A system with fractal structure usually behaves chaos. As a complicated nonlinear dynamics system, heart has fractals structure and behaves as chaos. The deeper inherent mechanism of heart can be opened out when the chaos and fractals theory is utilized in the research of the electrical activity of heart. Generally a time series of a system was used for describing the status of the strange attractor of the system. The indices include Poincare plot, fractals dimension, Lyapunov exponent, entropy, scaling exponent, Hurst index and so on. In this article, the basic concepts and the methods of chaos and fractals were introduced firstly. Then the applications of chaos and fractals theories in the study of electrocardial signal were expounded with example of how they are used for ventricular fibrillation.
Electrocardiography ; methods ; Fractals ; Humans ; Nonlinear Dynamics ; Signal Processing, Computer-Assisted ; Stochastic Processes

OBJECTIVEIn order to accurately reconstruct the acoustic source image, the application of transducer's receiving characteristics in magneto-acoustic tomography with magnetic induction (MAT-MI) is studied.

METHODSThe conductivity phantom model is built, and the magnetic acoustic signals are simulated and the acoustic sources are reconstructed according to the transducer's receiving characteristics.

RESULTSThe reconstructed image of acoustic source is consistent with the topographic shape and size of the phantom model.

CONCLUSIONMAT-MI based on the transducer's characteristics lays the foundation for further study.

The strain of Cunninghamella echinulata 9980 was first selected with high aminoacylase activity . In three submerged cultures, the aminoacylase activity in the mycelial cell was compared . A number of factors have effects on the resolution reaction. The results showed that, peptone culture gave the highest aminoacylase activity with 680U/g.The optium temperature,pH,and substrate concentration were 55℃, 7.0,and 0.2mol/L,respectively. The ions in the buffer lowered the activity,but the Co~(2+) in 10~(-4)~10~(-3 )mol/L was necessary for its activity.

Objective To study the changes of somatostatin(SOM) in plasma and cerebrospinal fluid (CSF) of children with convulsive diseases.Methods Sixty-seven children with convulsive diseases were studied as following:obtaining the samples of plasma in the 1st and 7th day after being in hospital,and the samples of CSF in the 1st after being in hospital.We investigated the changes of SOM in plasma and CSF with radioimmunoassay(RIA).Results 1.Convulsive group:the concentration of SOM in plasma in the 7th day(29.47?9.40 ng/L) was significant lower than that in the 1st day(39.23?11.00 ng/L)(t=21.530 P0.05).The concentration of SOM in plasma in the 1st day in control group was(19.58?6.04) ng/L.There were significant differences in convulsive group and encephalitis group without convulsion, control group(t= 6.847,7.921 P

L-theanine (γ-glutamylethylamide) is the main free amino acid component of tea and its favorable physiological effects on mammals have been reported. An enzymatic method for optically pure L-theanine production with a new L-aminoacylases-production fungi Cunnighamella echinulata 9980 was developed. The optimum conditions for enzymatic catalysis were at pH 6.5 with 50 mmol/L N-Acyl-DLtheanine and 40 mmol/L CoCl2. After 12-h incubation at 50℃,22.5 mmol/L L-theanine was obtained, the conversion rate against N-Acyl-L-theanine being 90%. Cunnighamella echinulata and the aminoacylase were applied in preparation of L-theanine.

Adolescent ; Adult ; Brain Neoplasms ; diagnosis ; metabolism ; pathology ; surgery ; Female ; Follow-Up Studies ; Humans ; Magnetic Resonance Imaging ; Male ; Meningeal Neoplasms ; diagnosis ; metabolism ; pathology ; surgery ; Meningioma ; diagnosis ; metabolism ; pathology ; surgery ; Middle Aged ; Mucin-1 ; metabolism ; Neoplasm Recurrence, Local ; Reoperation ; Retrospective Studies ; Tomography, X-Ray Computed ; Vimentin ; metabolism ; Young Adult