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Biomedical subjects

L Beyer

Publications and source records attributed to L Beyer.

At least 37 records · Page 2Linked to original sources
PubMed1989

[Possibilities of objective assessment of the course of activation in ideomotor training].

An active exploration of movement tasks is accompanied with central nervous activation. Its systematical examination needs a teamwork of scientists of various branches of knowledge (i.e. physiology, psychology, sport sciences). Mental training (motor imagination - MI) was chosen as a model for such examinations. In connection with the execution of MI there are characteristic chances of the mean alpha frequency of the EEG, heart rate, respiration rate and skin conductance. The time course of these parameters depends on the number, the duration and the sequence of MI. A graduated submaximal load on ergometer has no influence on the course of the examined parameters. Our investigation allows the conclusion that different activation processes go on within different subsystems during the execution of MI. From a physiological point of view it seems to be necessary that a concrete paradigm of MI must be examined concerning the course of the parameters and, thus, to guarantee the effort of MI.

Adolescent↗
PubMed1986

Investigation into the functional characteristic of m. quadriceps femoris in man with "stimulation mechanography".

The force and positive slope under isometric conditions produced by electrically evoked contractions of the m. quadriceps femoris in man were measured during two days without physical work and on two days with different kind of exercise. The relationship between force and slope is described by a logarithmic function. The changes after exercise were different in dependence of the kind of exercise.

Biophysical Phenomena↗
PubMed1983

Changes in EEG power density spectrum during static muscle work.

Changes in parameters of the EEG power density spectrum were demonstrated in four healthy male subjects during fatiguing static muscle contractions (M. biceps brachii dexter). For the following EEG frequency bands (delta 1-4 Hz, theta 4-8 Hz, alpha 8-13 Hz, beta 13-20 Hz), the relative power and the peak frequencies were determined. A significant increase in the alpha peak frequency was observed during muscle work. This trend was evident in both the central leads (C3-A1, C4-A1) and the occipital (O1-A1), particularly when the subjects had their eyes closed. These changes in peak frequency might be connected with an increase in central nervous activation.

Adult↗
PubMed1975

Enteric fever in young Yoruba children.

Ninety-seven Nigerian children under 5 years of age had typhoid or paratyphoid fever proved by blood culture. The presented with fever, anaemia, gastrointestinal or neurological disturbances, and typhoid and paratyphoid appeared clinically indistinguishible. In this holoendemic malarial area, malaria was the most important differential diagnosis, and may have contributed to the concomitant anaemia seen in the majority of patients. Despite vigorous therapy with chloramphenicol or trimethoxazole, and blood transfusion where indicated, the mortality in both typhoid and paratyphoid was high (18% in both groups).

Age Factors↗
PubMed1975

[The functional motility of motor units of the gastrocnemius and soleus muscles in the rat under indirect stimulation depending on the stimulus frequency].

With increasing pulse rate (up to 150 square pulses/sec) applied for 1 second at the gastrocnemius and soleus muscle the amplitude of electromyographic response was found to decrease. An amplitude decrease of sum action potentials (AP) recorded from the muscle surface occurred already at pulse rates below 100 pulses/sec. For the gastrocnemius muscle, this amplitude fall in the medium pulse-rate region can be described by the relation: amplitude = -log-pulse rate. At the soleus muscle, the amplitude fall is shifted towards the higher frequencies. After intensive swimming of the animal the amplitude depression of AP at the gastrocnemius muscle occurs already at a lower rate, and departs from the aforementioned relation. The causes are looked for in the differential properties of the various muscle fibres.

Action Potentials↗