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Y Xiang

Publications and source records attributed to Y Xiang.

3 recordsLinked to original sources

Quality control in nerve conduction studies with coupled knowledge-based system approach.

Contemporary equipment used for nerve conduction studies is usually capable of computerized measurement of latency, amplitude, duration, and area of nerve and muscle action potentials and resulting conduction velocities. Abnormalities can be due to technical error or disease. Identification of technical error is a major element of quality control in electromyography, and artificial intelligence could be useful for this purpose. We have developed a coupled knowledge-based prototype system (QUALICON) to assess the correctness of recording and stimulating characteristics in routine conduction studies. QUALICON extracts numeric features from CMAPs or SNAPs, which are translated into symbolic form to drive a Bayesian network. The network uses high-level knowledge to infer the quality of stimulating and recording electrode placement as well as polarity and stimulus strength making recommendations as to the likely technical error when abnormal potentials are detected. A preliminary assessment shows that QUALICON performs as well as manual assessment performed by professionals.

Action Potentials

[Nosocomial infections of methicillin-resistant Staphylococcus aureus and their detection].

In 142 strains of Staphylococcus aureus randomly isolated from clinical samples in a year, methicillin-resistant Staphylococcus aureus (MRSA) accounted for 79.6% (113/142). MRSA in the samples from the respiratory, burning and hematological departments came to 92.0% (23/25), 84.6% (11/13) and 83.3% (30/36) in proportion respectively. 79.6% of MRSA strains were isolated from the patients in whom the infections were confirmed to be hospital-acquired. All the strains of Staphylococcus aureus examined were resistant to penicillin G and ampicillin, but sensitive to vancomycin. Twenty hospital-acquired strains of MRSA showed a resistance to all detected antibiotics (multi-drug resistance, MDR), but vancomycin; strains of methicillin-sensitive ones, however, showed on MDR. In 45 strains of Staphylococcus aureus isolated from swabs of fingers of 62 medical workers, 31 (68.9%) were methicillin-resistant. The resistant similarity of shares of strains between medical staff and patients indicated a potential role that medical workers play in spread of nosocomial infections.

Cross Infection

[Dissolution of metronidazole stilus].

Metronidazole stilus is a new preparation to be inserted into periodontal pockets for treatment of periodontitis. The certificate and file number of approval given to this new product were issued by the Ministry of Public Health in August, 1989. Its shape looks like a toothpick and the width, thickness and length are 1.5mm, 0.7mm and 3 cm, respectively. The content of metronidazole in each cm of the stilus is 2.2 mg. We have studied the dissolution of the new preparation by rotation basket method. The kinetic process of dissolution approximates first order kinetics. The K, t0.5 and t0.9 are 0.0624 min-1, 12.8 and 38.6 minutes, respectively. The requirement is that the dissolved percentage should not be lower than 60% of the added amount in 30 minutes. In order to have a dissolution test similar to that of the stilus in dental pockets, we examined the dissolution in static condition. The results showed that a very high dissolution rate appeared in the beginning, but it decreased quickly, and 71.76% of metronidazole was not dissolved until 48 hours. So one insertion per two days for clinical use is suggested.

Metronidazole