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111.
A negative relationship between platelet monoamine oxidase (MAO) activity and Sensation Seeking (SS) has been reported in several studies. This study evaluates the possible contribution of autonomic nervous system (ANS) activity to this relationship. Additionally, confirmatory factor analysis was used to create models of ANS concepts from a larger number of psychophysiological variables. Skin conductance (SC) and heart rate (HR) were recorded from 46 men and 49 women during a two-session protocol that included rest periods, a balloon stress, a series of tones, and two tasks: two-flash threshold and tachistoscopic recognition. Results showed that the best-fitting models for both rest and task periods included concepts of SC base levels (“arousal”), SC lability, and HR, and were quite similar for men and women. MAO activity correlated positively with SC concepts, most strongly for women. Women showed negative relationships between sensation seeking and both SC arousal and HR concepts. In contrast, men showed evidence of positive relationships between SC concepts and an active life style. The sex differences and response specificity in these relationships make it unlikely that ANS activity mediates the negative MAO-SS relationship. 相似文献
112.
113.
In order to investigate the effect of individual differences in imagery vividness on habituation rate, 14 subjects were threatened with receiving and then imagined receiving an electric shock. Subjects first habituated to a tone which was then used as an auditory signal for the shock threat and the imagined shock. The skin conductance response (SCR) was used to follow the course of habituation. Results demonstrated that subjects with non-vivid imagery habituated to the tone more rapidly than subjects with vivid imagery when the tone was associated with imagining an electric shock. Implications of this finding for therapeutic techniques using instructed imagery are discussed. 相似文献
114.
Skin deposits in hereditary cystatin C amyloidosis 总被引:3,自引:0,他引:3
Eiríkur Benedikz Hannes Blöndal Gunnar Gudmundsson 《Virchows Archiv : an international journal of pathology》1990,417(4):325-331
Summary Clinically normal skin from 47 individuals aged 9–70 years was investigated. Cystatin C amyloid deposits were found in various locations of the skin by light and/or electron microscopy, in all 12 patients with a clinical history of hereditary cystatin C amyloidosis (HCCA). Six asymptomatic individuals, who had the Alu 1 restriction fragment length polymorphism (RFLP) marker reported to cosegregate with the disease, also had cystatin C amyloid deposits in the skin. Three asymptomatic individuals (age 17–46) belonging to the HCCA families were without amyloid in the skin but had Alu 1 RFLP marker. Skin from 12 individuals who served as controls and skin from 14 close relatives of the patients was negative for amyloid. Punch biopsy of the skin is a simple procedure which is of value for the diagnosis of HCCA, even before the appearance of clinical symptoms. This method might also be of use in following progression of the disease. 相似文献
115.
Simultaneous measurements of skin potential (SP) and skin resistance (SR) obtained from 20 male and 20 female adult subjects during 2 sessions held 2 to 9 days apart were used in studying (1) the correlation of change measurements and prestimulus level in the two measures, and (2) the amount of correlation between SP and SR using both simple difference and residual change scores in which the regression of poststimulus values on initial level (prestimulus) has been controlled. Correlations within Ss and correlations among Ss showed large individual variability, correlation differences between males and females, and high correlation between SP and SR change scores. Although the law of initial value (LIV) seemed to have little applicability to the measurement of electrodermal responses, the results underscored the need to control for contamination of change measures by initial level regardless of direction. 相似文献
116.
Meyer PF Gadsby PD Van Sickle D Schoenlein WE Foster KS Graber GP 《Medical & biological engineering & computing》2005,43(2):225-229
A new type of disposable external defibrillation electrode has been developed to reduce the skin irritation commonly associated
with defibrillation and synchronised cardioversion. This design employs an impedance gradient to reduce the proportion of
current delivered to the electrode periphery. The temperature distribution under the new electrode was compared with that
of four other types of commercially available electrodes after repeated high-energy biphasic defibrillation discharges to
domestic swine. Skin temperature distributions were acquired using non-invasive thermography. Measurements of the maximum
temperature rise at each electrode site, taken 3.6s after the fifth defibrillation discharge, demonstrated that the new impedance-gradient
electrode produced 50–60% less skin heating than two of the three uniform-impedance electrode designs. Histological examination
of erythematous sites excised 24h after defibrillation quantified the associated skin damage using a scoring protocol developed
for this study. In contrast to previous studies, histological examinations demonstrated second-degree skin burns following
defibrillation. The new electrode design, however, induced 44–46% less skin damage than two of the traditional uniform-impedance
electrodes. 相似文献
117.
118.
In 16 neurological patients with different levels of severely disturbed vigilance and 16 healthy subjects electrodermal responses to the name and the name backwards were elicited. In the most severely impaired patients, no differences were found between stimulus conditions. In less severe cases, significantly larger responses to the name were found but only on initial trials. In normal subjects differences persisted throughout 10 presentations of each stimulus. All subject groups demonstrated habituation. 相似文献
119.
Mahmud Ahmad Hasan Abbas Sayedul Haque 《American journal of medical genetics. Part A》1993,46(4):369-371
A Pakistani kindred comprising 5 generations contained 9 males and 4 females with alopecia universalis as a single abnormality without any associated defects. The skin biopsy from the scalp showed hair follicles without hair. Analysis of the pedigree is strongly suggestive of autosomal recessive inheritance, and consanguineous loops could account for all affected persons being homozygous for the abnormal allele. © 1993 Wiley-Liss, Inc. 相似文献
120.
Laser Doppler flowmetry with optical-fibre beam transmission is a sensitive fast and convenient method of measuring tissue
blood flow. However, its sensitivity can also be a problem because of movement artefacts. This study applies some basic considerations
of fibre optics and Rayleigh light scattering to the field of laser Doppler blood flow meters. Practical suggestions are given
by which movement arterfacts can be reduced by choice of optical fibres, attention to probe geometry, cladding the fibres
to reduce their movements and in the method of application. Experiments which test the normalisation circuitry of laser Doppler
instruments are described and the effects of movement artefacts on the interpretation of the pulsatile component of laser
Doppler records are also discussed. Probe and fibre line movements cause high-frequency intensity fluctuations due to speckle
movement. The intensity fluctuations produce an apparent Doppler shift much greater than the Doppler shift produced by the
relative movements of probe and tissue. It has been found that it is important to ensure that the fields of view of the illuminating
and detecting fibres do not overlap at the skin surface and that probe contact with the skin surface should be maintained. 相似文献