摘要:

From the mathematical model of the human vestibulo-ocular reflex (VOR) system, the frequency response has been calculated for harmonic sinusoidal acceleration. The addition of an adaptation term to the second order model, describing the cupular behaviour, results in considerable changes in the response characteristics in the low frequency region. An attempt has been made to quantify the influence of the cupular time constant T1 and the adaptation time constant Ta on the amplitude and phase characteristics of the transfer function, which represents the human VOR system. The results of this theoretical study will be employed in the following paper.

ISSN:0301-1569    

DOI:10.1159/000275627

出版商:S. Karger AG    

年代:1983

数据来源: Karger

摘要:

The frequency response of the human vestibulo-ocular reflex (VOR) system was investigated by determining its amplitude and phase characteristics. The angular head velocity and the resulting angular eye velocity were measured in 7 healthy subjects using a rotation room. Rotations about a vertical axis were carried out at frequencies ranging from 0.0025 to 0.1 Hz; peak head velocity was 50°/s. From the experimental data, the gain and the phase relationship were calculated. The results appear to be in agreement with the frequency response of the theoretical transfer function which represents the VOR system. This is based on a second order differential equation for cupular behaviour, modified by an adaptation term. According to the experimental phase characteristic the cupular restoration time constant T1 was 16.6 s, and the adaptation time constant was 114 s. Linearity of the VOR system, both for amplitude and phase, was demonstrated at frequencies of 0.05 and 0.005 Hz

ISSN:0301-1569    

DOI:10.1159/000275628

出版商:S. Karger AG    

年代:1983

数据来源: Karger

摘要:

The effect of experimental occlusion of the Eustachian tube in rats has been studied. Only in germ-free animals it has been possible to eliminate infection as a complicating factor. The formation of new bone in the wall of middle ear and bulla was apparent soon after occlusion, even in the absence of infection. These findings suggest that tubal occlusion causing serous otitis media can lead to extensive changes in the bone lining the middle ear cavity and this could explain the condensation of bone found in ears without any apparent sign of infection.

ISSN:0301-1569    

DOI:10.1159/000275629

出版商:S. Karger AG    

年代:1983

数据来源: Karger

摘要:

An unusual case of a mixed tumor of the skin of salivary gland type arising from the tip of the nose is presented. The literature is reviewed.

ISSN:0301-1569    

DOI:10.1159/000275630

出版商:S. Karger AG    

年代:1983

数据来源: Karger

摘要:

Red blood cell, serum and tissue Mg concentrations in 100 subjects with aged 34–78, with squamous cell carcinoma of the larynx were determined by atomic absorption spectrophotometry. The concentration of this cation in cancerous tissues was found to be about twice as high as in the unchanged homologous tissues of the host. This was accompanied by a systemic deficiency manifesting itself by a decreased Mg concentration in red blood cells, serum and muscles which became more pronounced as the disease advanced, and returned to normal after radical treatmen

ISSN:0301-1569    

DOI:10.1159/000275631

出版商:S. Karger AG    

年代:1983

数据来源: Karger

摘要:

Voice therapy is often most effective for treating patients with vocal cord polyp, polypoid degeneration and singer’s nodule. However, little is known about the total speaking times in 1 day, the ratio of speech per hour and the sound level during speech, in individual patients. If these parameters can be readily detected, it could be clarified as to how speaking times or patterns are related to a particular voice disorder and/or what instruction a doctor had given a patient. We devised a speech accumulator which records the vibration time of the vocal cords by a small contact microphone attached to the neck, but does not record the actual speech, thus monitoring the privacy of the individual. The time of speech, at any sound level can be read digitally, at any time. This system was clinically used for 11 patients and proved to be most useful. The longest speaking time in 1 day was 182 min, for a bus guide, and the shortest time was 33 min for an office cler

ISSN:0301-1569    

DOI:10.1159/000275632

出版商:S. Karger AG    

年代:1983

数据来源: Karger

ISSN:0301-1569    

DOI:10.1159/000275633

出版商:S. Karger AG    

年代:1983

数据来源: Karger

ISSN:0301-1569    

DOI:10.1159/000275634

出版商:S. Karger AG    

年代:1983

数据来源: Karger