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At least 19 recordsLinked to original sources
PubMed1979

[The influence of electric 50 Hz fields on humans (author's transl)].

The investigations concerning the influence of supply-frequent electric fields on man have been carried out on 12 subjects in 24 single trials. A field intensity as it occurs in the height of the subjects' head under a 380 kV high voltage transmission line was used. Some physiological parameters like ECG, EEG, blood pressure, blood gas and reaction time have been recorded and analyzed. The parameters were both analogously recorded and digitally stored as indicated in Fig. 2. Some of the investigations were carried out under mental load of the subjects and showed that the changes in the heartrate due to this load cover the switch-off effect of the heartrate. For the other parameters like EEG, reaction time, blood gas and blood pressure no influence of the investigated field intensity on man could be found.

Acoustic Stimulation↗
PubMed1978

Sequence of return of neurological function and criteria for safe ambulation following subarachnoid block (spinal anaesthetic).

Twenty-three adult men were studied during and after subarachnoid block anaesthesia for elective surgery. Measurements were obtained of mean arterial pressure and pulse, both supine and after standing for five minutes, core body (tympanic) and peripheral skin (toe) temperatures and blood flow in the leg. Time of measurements included one hour after the injection of tetracaine and after regression of the block. Results obtained indicate that the sequence of return of neurological activity following tetracaine subarachnoid block is sympathetic nervous system activity, pinprick sensation, somatic motor function followed by proprioception in the feet. This progression provides the basis for recommended criteria which indicate when it is safe for patients who have been subarachnoid block anaesthesia to become ambulatory. These criteria include: (1) return of pinprick sensation in the peri-anal area (sacral 4--5); (2) plantar flexion of the foot (while supine) at pre-anaesthetic levels of strength; and (3) return of proprioception in the big toe, always provided that the patient is not hypovolaemic or sedated.

Adult↗
PubMed1978

Somatostatin--paracrine and neuromodulator peptide in gut and nervous system.

Somatostatin, a tetradecapeptide widely distributed in nervous tissue and gut, has inhibitory effects on secretion and neuromuscular activity. The actions of this peptide probably embrace three types of transmitter-receptor interaction, namely that of a neurotransmitter in the nervous system, that of a hormone in the hypophyseal portal circulation and that of a local (paracrine) effector in gut and pancreas.

Animals↗
PubMed1976

Neurophysiology of locomotor automatism.

It had long been known that the decapitated cock can cross a yard. During the last century an automatic mechanism controlling stepping movements has also been found in other vertebrates. The system controlling locomotion has many features similar to these systems controlling other natural movements: respiration (28), micturition (98), scratching (154), mastication (33), etc. Today we know that there are spinal automatisms for each limb generating its stepping movements. Activity of these automatisms depends essentially on the afferent inflow from the moving limbs. There also is interaction of the limbs during locomotion that promotes their coordination. The existence of two descending systems with different functions in the control of locomotion (Fig. 1) also can be considered as an established fact. Activity of a number of neurons involved in the control of locomotion has been studied directly during locomotion in decorticate, thalamic, and mesencephalic cats. To explain the experimental data at hand, several hypotheses of organization of the spinal automatism of stepping have been forwarded: a chain-reflex hypothesis, a hypothesis of two reciprocal half-centers, and a ring hypothesis (Fig. 2). Although general features of the system controlling locomotion are more or less clear, many questions are not yet answered. It is unknown what relative contributions to motoneuronal activity are made by proprioceptive reflexes versus influences from the automatism of stepping. Furthermore the structure of the spinal stepping automatism is not known. It is not clear if the spinal stepping automatisms of the forelimbs are as potent as those of the hindlimbs. The descending system responsible for activation of the spinal automatism of stepping has not yet been identified in direct experiments. The inputs and outputs of the subthalamic and midbrain "locomotor" regions have not been found, and we know almost nothing about intrinsic interaction of neurons in these regions. The role of inhibitory thalamic influences is scarcely known. Finally, we have no data concerning the influence of either cortical (42, 186) or visual mechanisms in locomotor control.

Afferent Pathways↗