[Rapid screening questionnaire based on clinical symptoms of patientswith benign paroxysmal positional vertigo].

Objective:To fomulate a rapid screening questionnaire for benign paroxysmal positional vertigo (BPPV) according to the symptoms of patients with BPPV. Method:A total of 276 patients with dizziness participated in this study, and 219 cases were included in the questionnaire validity evaluation except for 48 patients who participated in the revision of the questionnaire and 9 patients with inconsistent diagnosis. Subjects were divided into BPPV group and non-BPPV group according to the diagnostic criteria. ①All patients completed questionnaires based on positional dizziness, and the differences between the two groups were compared. ②Reliability test adopted test-retest reliability and Cronbach's α coefficient; content validity adopted expert judgment method, and structural validity adopted factor analysis. Result:①Reliability test: test-retest reliability was 0.945, Cronbach's α coefficient was 0.649. Validity test: KMO value was 0.720. Two factors were used with a characteristic root of higher than 0.9. The total cumulative contribution rate was 61.2%. ②Results of the questionnaire: The patients who developed dizziness when getting up/down or turning over in bed, accounted for 78(94.0%) in the BPPV group and 57(41.9%) in the non-BPPV group, with a statistical difference (P<0.01). In the cases of vertigo, there were 82 cases (98.8%) in the BPPV group and 96 cases (70.6%) in the non-BPPV group, with a statistical difference (P<0.01). There were 65 cases (78.3%) in the BPPV group and 53 cases (39.0%) in the non-BPPV group with dizziness/vertigo attack time less than 1 minute, with a statistical difference (P<0.01). Patients who had hearing loss or tinnitus during the dizziness episode accounted for 8(9.6%) in the BPPV group and 31 (22.8%) in the non-BPPV group, with a statistically difference (P<0.05). The patients with consciousness during dizziness episode were in 79 patients (95.2%) in the BPPV group and 128 patients (94.1%) in the non-BPPV group, with no statistical difference (P>0.05). Conclusion:This questionnaire has clinical applicability and can be used for rapid differential screening of BPPV in patients with dizziness.

[A control study of personality characteristics and variation of plasma peptide in pilots with neurosis].

Objective. To study the relationship between personality type and variation of plasma peptides in pilots with neurosis. Method. A case-control study was used. 124 male pilots were evaluated with Eysenck's personality checklist, and then level of certain plasma peptides, such as vasoactive intestinal peptide (VIP), beta-endorphin (beta-EP) and angiotensin-II (A-II) were determined. Result. There were significant difference in personality characteristics and personality types between pilots with neuroses and the control. The contents of VIP and beta-EP in plasma showed visible difference between disease group and control. Content of beta-EP in those with inner-unstable type personality was lowest among all the various types. Conclusion. Personality characteristics were different between pilots with neurosis and controls. Levels of VIP and beta-EP in disease group were lower than those in the control. Different personality types had different levels of beta-EP in pilots with neurosis.

The electrogenerated chemiluminescent behavior of hemin and its catalytic activity for the electrogenerated chemiluminescence of lucigenin.

The electrogenerated chemiluminescent (ECL) behavior of hemin at a platinum electrode in the alkaline solution has been investigated in detail. Under the optimum conditions the linear response range of hemin is 1.0 x 10(-5)-1.0 x 10(-8) g ml(-1), the detection limit was 1.0 x 10(-8) g ml(-1), and the relative standard derivation for 1 x 10(-7) g ml(-1) hemin was 2.8%. It has been also found that hemin would catalyze the ECL of lucigenin at a platinum electrode in a neutral solution in the presence of hydrogen peroxide, the catalytic ECL intensity was linear with the concentration of hemin in the range of 1.0 x 10(-14)-1.0 x 10(-10) g ml(-1). IgG labeled with hemin was used to examine the ECL catalytic activity of hemin after conjugating to protein, and the results showed that hemin retained ECL catalytic activity when conjugated to protein.

Coulometric detector based on porous carbon felt working electrode for flow injection analysis.

A coulometric detector based on carbon felt as working electrode has been designed. Ascorbic acid, hydroquinone, gallic acid and sulfur dioxide were used as electroactive compounds to determine the electrochemical characteristics of this detector. The coulometric conversion efficiency, selectivity, linear response range, detection limit and mass transfer coefficient were investigated in order to use the detector as a cleanup device in a flow injection system with dual-detector. This system has been used for determination of sulfur dioxide in wine, and the results are compared to those from the aspiration-oxidation method.

Adsorptive and electrochemical behaviors of estradiol valerate at a mercury electrode.

It was found that estradiol valerate could be adsorbed at a mercury electrode under open circuit. The adsorptive and electrochemical behaviors of estradiol valerate on a static mercury electrode were investigated by cyclic voltammetry, linear scan voltammetry and chronocoulometry. Based on this, a sensitive and selective adsorptive stripping square-wave voltammetric method was developed for the determination of estradiol valerate based on the optimization of solution conditions and electrochemical parameters. It was found that in a Britton-Robinson buffer solution containing 18% alcohol (pH 9.5), estradiol valerate gave a sensitive reductive peak at potential -1.29 V (vs. SCE) and the peak current was linear with the concentration of estradiol valerate in the range 2.0 x 10(-8)-2.5 x 10(-6) mol L-1. The detection limit was 1.1 x 10(-8) mol L-1. The interference of some common steroid estrogens was examined and it was found that they did not interfere in the determination of estradiol valerate in the present system.