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Zhengxiang Xie

Publications and source records attributed to Zhengxiang Xie.

6 recordsLinked to original sources

[Analysis on time-frequency feature of rabbit cortical somatosensory evoked potential].

This experiment was carried out to analyze the time-frequency feature of rabbit cortical somatosensory evoked potential (SEP). Rabbit was narcotized and subjected to craniotomy. SEP was from sensory and motor cortex. Stimulation was continuing many times and signal was sampled at 3 800 Hz. The peak latency of each waveform was measured. Power spectrum of SEP was analyzed. The time-frequency feature of single-trial was compared with that of average SEP. It was found that the variability of single-trial SEP latency enlarges with time in a stimulation period. The spectrum of SEP includes three main frequency spectrum packages. The technique of summation makes a lot of signal aberration such as waveform confluence, new waveform emerging and after-discharging components dismissing.

Animals↗

[Acute effects of low and moderate doses of alcohol on coordinate motor and autonomic nervous function in a group of healthy Hans].

The autonomic nervous function, blood pressure, coordinate motor and blood alcohol Concentration (BAG) of twenty-one healthy Han volunteers were examined before and after alcohol intake. The purpose was to assess the acute effects of low and moderate doses of alcohol on their coordinate motor and autonomic nervous function. The results showed that after alcohol intake the subjects' heart rate increased and the total power value (TPV) decreased significantly. After the intake of alcohol at low dose, the parasympathetic nervous function of the subjects lying supoine was inhibited significantly. After the intake of alcohol at moderate dose, both the parasympathetic and the sympathetic nervous functions were inhibited. After the intake of alcohol at low dose, both the systolic pressure and the diastolic pressure of the subjects standing up-right were decreased and the diastolic pressure of those lying supine were also decreased. After the intake of alcohol at moderate dose, the systolic and diastolic pressures of the subjects, either lying supine or standing up-right, were decreased. Some subjects showed ataxia after the intake of alcohol at low dose ,and some showed aggravated ataxia after intake of alcohol at moderate dose of alcohol. There was no relationship of BAG with the degree of changes in autonomic nervous function, blood pressure and ataxia. The results indicated that ataxia was induced to come on and the autonomic nervous function was inhibited in some subjects who had taken low and moderate doses of alcohol ,and the cardiovascular regulation was affected too. These suggested that the increase of alcohol intake is adverse to human body's adaptation to the sharp change of circumstance.

Adult↗

[Genotype combination distribution of 5-site SNPs in 3 subtypes of beta adrenoceptor].

DNA was extracted from the peripheral venous blood of 338 subjects using BLOOD DNA MINI KIT. The 5 site SNP in 3 subtypes of Beta-AR were genotyped by PCR-RFLP (polymerase chain reaction-restriction fragment length polymorphism) and allele-specific primer PCR techniques. The genotypes combination distribution of SNP at 5 sites in the 3 subtypes of Beta-AR were determined by clustering analysis technique. The natural combination distribution characteristics for SNP at 5 sites in the 3 subtypes of Beta-AR in 338 subjects were obtained. Sixty-seven combinations types were found. The preceding 5 combinations in the natural combination distribution of the SNP were: (1) The genotype combination of forty subjects was B1-AR S/S49+B1-AR R/R389+B2-AR R/G16+B2-AR Q/E27+B3-AR W/W64, its probability was 11.83%. (2) The genotype combination of thirty-three subjects was B1-AR S/S49+B1-AR R/R389+B2-AR R/G16+B2-AR Q/Q27+B3-AR W/W64, its probability was 9.76%. (3) The genotype combination of nineteen subjects was B1-AR S/S49+B1-AR R/G389+B2-AR R/G16+B2-AR Q/Q27+B3-AR W/W64, its probability was 5.62%. (4) The genotype combination of sixteen subjects was B1-AR S/S49+B1-AR R/G389+B2-AR R/G16+B2-AR Q/E27+B3-AR W/W64, its probability was 4.74%. (5) The genotype combination of thirteen subjects was B1-AR S/G49+B1-AR R/R389+B2-AR R/G16+B2-AR Q/E27+B3-AR W/W64, its probability was 3.85%. The obvious correlations exist among full sample and female or male subgroup, and between female and male subgroups.

Adult↗

[Separating independent components in heart period signal].

To extract sub-signal of heart period signal (HPS), a new statistical signal processing approach, namely independent component analysis (ICA) was addressed. Electrocardiosignal (ECS) was acquired from ten volunteers. ECS was sampled 8 minutes when the volunteer was in supine position, and then when the same volunteer was in erect position. HPS was extracted from ECS. According to time-delay, HPS was divided into five groups as mixed signals. Five signals were reconstructed into two groups by ICA. The rebuilt signals were transformed by Fourier transformation. One centralized in low frequency (called IC1); the other did in high frequency (called IC2). The power of IC1 was significantly increased (P<0.01) while that of IC2 showed no significant change (P>0.05), and the ratio of IC1 to total power also significantly increased with the change from supine position to erect position. Comparsion between the two postural results reveals that IC1 may express sympathetic activity, and IC2 represents parasympathetic activity. Sympathetic and parasympathetic nervous functions can be evaluated respectively and quantitatively by use of data and graphs from the two decomposed components.

Autonomic Nervous System↗

[A computer-aided image diagnosis and study system].

The revolution in information processing, particularly the digitizing of medicine, has changed the medical study, work and management. This paper reports a method to design a system for computer-aided image diagnosis and study. Combined with some good idea of graph-text system and picture archives communicate system (PACS), the system was realized and used for "prescription through computer", "managing images" and "reading images under computer and helping the diagnosis". Also typical examples were constructed in a database and used to teach the beginners. The system was developed by the visual developing tools based on object oriented programming (OOP) and was carried into operation on the Windows 9X platform. The system possesses friendly man-machine interface.

Diagnosis, Computer-Assisted↗

[Analyzing heart period signal for fetus and pregnant woman in perinatal period].

Analyzing the digital characteristics (chaotic and spectral features) of fetal and pregnant woman's heart period signal (HPS) can assess the autonomic nervous system function. Extracting and analyzing HPS of fetal and pregnant woman in perinatal period were realized by using the method of visual programming. The subjects were in supine position. Electrocardiography-signal (ECS) from the leads placed at symphysis pubic bone to inferior border of abdominal wall was acquired. ECS was preprocessed by wavelet filter. The sophisticated technique developed by our laboratory was used to analyze the digital characteristics of HPS. The system could be used to assess fetal and pregnant woman's autonomic nervous system function, furthermore, sympathetic and parasympathetic nervous function could be evaluated respectively and quantificationally. The system also could be used to prognosticate fetal distress. The digital characteristics of fetal and other age groups' HPS, which vary with age, suggest the physiological process of development, mature and senility of autonomic nervous system; based on it, we could find the way of anti-senility. Some digital parameters of fetal HPS stand between those of newborn and adult, which may imply that fetal autonomic nervous regulation is influenced by mother's nerve and endocrine system.

Adult↗