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Biomedical subjects

J Cheng

Publications and source records attributed to J Cheng.

At least 307 records · Page 17Linked to original sources
PubMed1997

Effects of electroacupuncture on extracellular contents of amino acid neurotransmitters in rat striatum following transient focal cerebral ischemia.

In this study, we investigated the effects of electroacupuncture (EA) on extracellular levels of amino acid neurotransmitters (glutamate, aspartate, and taurine) in striatum and cerebral infarction dimensions in rats subjected to transient focal cerebral ischemia induced by 2 hours of middle cerebral artery (MCA) occlusion. EA (15 HZ, 6 mA), delivered to points of "Fengfu" (Du. 16) and "Jinsuo" (Du. 8), remarkably reduced the cerebral infarction volume. EA significantly decreased the ischemia-induced increase of extracellular aspartate level, while substantially enhancing the elevation of taurine induced by ischemia. These results indicated that the neuroprotective effect of EA against cerebral ischemia may be related to a bidirectional regulation of extracellular excitatory and inhibitory amino acid levels.

Animals↗
PubMed1997

[The relationship between prognosis, metastasis and microvessel quantity in invasive breast carcinoma].

OBJECTIVE: To determine the prognostic value and relationship of microvessel quantity (MVQ) with PCNA, c-erbB-2, nm23-H1 and Cathepsin D in invasive breast carcinoma. METHODS: Immunohistochemical techniques (LSAB) were used to detect the expression of PCNA, c-erbB-2, nm23-H1, Cathepsin D and MVQ in 76 cases of invasive breast carcinoma. RESULTS: The mean of MVQ was 57.82 +/- 22.22 in 76 cases of invasive breast carcinoma. The expression of Cathepsin D (cancer cells), c-erbB-2 and node positive were not related to MVQ. MVQ was positively correlated to expression of Cathepsin D (stroma cells), PCNA and distant metastasis (10 years), but negatively correlated to 5 year survival. CONCLUSION: MVQ was significantly correlated to distant metastasis and survival period in invasive breast carcinoma. MVQ may be an independant prognostic indicator.

Adult↗
PubMed1997

[Extraction of P3 wave from ERP by using the wavelet transform].

A new time-frequency filter based on correlation of wavelet transform coefficient between mean ERP and single ERP is presented in this paper. This filter can extract the P3 wave from the background of eye-moving and spontaneous EEG activity.

Acoustic Stimulation↗
PubMed1997

[Study on the relationship between PS2 protein expression and prognosis in invasive breast carcinoma].

OBJECTIVE: To study the relationship between the expression of PS2 protein and prognosis in the invasive breast cancer (IBC). METHOD: Using LSAB immunohistochemical method, PS2 protein expression in 86 cases of IBC was detected. RESULTS: The positive rate of PS2 protein was 66.27% (57/86) in 86 cases of IBC. Under the following 3 conditions, PS2 protein expression levels in the more-than-5-year-survival group (A) were higher than those in the less-than-5-year-survival group (B). (1) In 86 cases of IBC, the expression level was 80.55% (29/36) for Group A, Significantly different from the 56.00% (28/50) of Group B (P < 0.025). (2) In 62 cases of premenopausal patients, the corresponding data were 86.20% (25/29) and 54.54% (18/33) respectively, P < 0.005; whereas in 24 cases of postmenopausal patients, 4/7 and 58.82% (10/17) respectively, P > 0.5. (3) In 62 cases of axillary node positive patients, the expression levels for Groups A and B were 82.35% (14/17) and 55.55% (25/45) respectively, P < 0.05; while in 24 cases of axillary node negative patients, 78.94% (15/19) and (3/5) respectively, P > 0.5. CONCLUSIONS: These results suggest that the expression of PS2 protein was positively correlated with 5-year-survival in IBC, and could be considered as a prognostic predictor for breast cancer, PS2 protein expression was a useful indicator for endocrine therapy in premenopausal patients. In axillary node positive patients, the expression of PS2 protein was associated with a better prognosis.

Adult↗
PubMed1997

[Study of mechanism of PTH modulating cytosolic free calcium in rat DCT].

OBJECTIVE AND METHODS: In order to understand the mechanism of PTH in regulating cytosolic free calcium concentration ([Ca2+]i), we differentiated rat renal proximal and distal convoluted tubules (PCT&DCT) by Percoll density gradient centrifugation, and successfully gauged the effect of hPTH (1-84), dibutyryl cAMP (db cAMP, a kind of cAMP activator) and prostaglandin E2 (PGE2) on [Ca2+]i of DCT using fluorescent Ca2+ indicator Fluo 3-AM. We found that PTH, db cAMP and PGE2 all could increase [Ca2+]i. RESULTS: The results suggest that the rise in [Ca2+]i induced by PTH in DCT was through activation of cAMP, and PGE2 might be also involved in regulation of [Ca2+]i as a messenger of PTH.

Animals↗
PubMed1997

[Preliminary study of anatomic relation among nasopalatine duct, central incisor root and floor of nasal cavity with X-ray measurement].

The authors studied anatomic constructure of anaterior maxilla. They observed the position relationships among nasopalatine duct, central incisor root and floor of nasal cavity through X-ray measurement. The results showed: (1) Average distance between the anterior wall of nasopalatine duct and cortical plate of anterior maxilla was 7.80 +/- 1.43 mm. (2) Average distance between the anterior wall of nasopalatine duct and central incisor root was 4.15 +/- 1.48 mm. (3) Average distance between the tip of central incisor root and floor of nasal cavity was 12.62 +/- 2.47 mm. (4) Average length of the nasopalatine duct was 15.04 +/- 2.20 mm. The results are beneficial of dental implantation and orthognathic surgery.

Adult↗
PubMed1997

[Treatment effects of fibroblast growth factors on blast-induced hearing loss].

Nineteen guinea pigs were chosen to measure the compound action potential (CAP) using the silver-ball electrode before and after explosion and 48 h after perfusion of acidic fibroblast growth factor (aFGF) and basic fibroblast growth factor (bFGF). After explosion the average CAP thresholds in the group perfused with bFGF and aFGF were 88.7 dB and 93.2 dB SPL respectivery, the CAP threshold in the control group was 119.4 dB SPL. The difference was significant. The results of the hair cell count from the surface preparation of the cochlea showed that hair cell damage in the control group was more severe than that in the group perfused with aFGF and bFGF. It suggests that aFGF and bFGF perfused to the cochlea may facilitate recovery processes of hearing loss and help to repair the hair cell following acoustic trauma.

Action Potentials↗
PubMed1997

[Research on power Doppler ultrasound imaging technique].

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.

Blood Flow Velocity↗
PubMed1997

[The effects of hypoxia on wavelet decomposition of event-related potential].

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.

Acoustic Stimulation↗
PubMed1997

[The methods of mean scatterer spacing estimation and its application].

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.

Anthropometry↗
PubMed1997

[Analysis of single cells by capillary electrophoresis].

A review with 46 references is given on the application of capillary electrophoresis to the analysis of single cells. Injection modes, detectors and future prospects of this microseparation technique for single-cell analysis are described in detail.

Animals↗
PubMed1997

Diagnosis of Duchenne/Becker muscular dystrophy and quantitative identification of carrier status by use of entangled solution capillary electrophoresis.

Use of capillary electrophoresis, a new and useful analytical tool, offers a variety of advantages for nucleic acid analyses, including rapid analysis, automation, high resolution, qualitative and quantitative results, and low consumption of both sample and reagents. We report the first example of the use of entangled solution capillary electrophoresis (ESCE) and laser-induced fluorescence detection (LIF) for separation-based diagnostics in the quantitative analysis of multiplex PCR products for determination of carrier status of Duchenne/ Becker muscular dystrophy (DMD/BMD). This approach greatly improved the speed, resolution, and sensitivity of information needed for the diagnosis of DMD/BMD compared with that from conventional diagnostic methods, and is of general utility for diagnosis of genetic diseases.

Electrophoresis, Capillary↗
PubMed1997

Novel homozygous and compound heterozygous mutations of sterol 27-hydroxylase gene (CYP27) cause cerebrotendinous xanthomatosis in three Japanese patients from two unrelated families.

The autosomal recessively inherited cholesterol metabolic disease, cerebrotendinous xanthomatosis (CTX), is caused by mutations in the sterol 27-hydroxylase gene. Three Japanese CTX patients from two unrelated families were studied genetically. By DNA sequence analysis a novel mutation of A for G substitution at amino acid position 372 (CGG 372Arg to CAG 372Gln) was identified in one of the CTX families. The mutation was also found in two patients from the other family, with a compound heterozygous pattern of A for G substitution at amino acid position 441 (CGG 441Arg to CAG 441Gln). The latter mutation was the same as previously reported by our group (J. Lipid Res. 1994. 35: 1031-1039). As the two mutations changed the restriction enzyme sites, rapid screening methods were developed for the detection of the carriers. Transfection of the two mutant cDNAs into COS cells resulted in markedly reduced sterol 27-hydroxylase activity. These results indicate that the two mutations are responsible for the deficiency of the sterol 27-hydroxylase activity in these patients. The features of mutations identified till now in Japanese CTX patients are also reviewed.

Cholestanetriol 26-Monooxygenase↗