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Biomedical subjects

G Wiesspeiner

Publications and source records attributed to G Wiesspeiner.

15 recordsLinked to original sources
PubMed1996

Instrumentation for assessment of tremor, skin vibrations, and cardiovascular variables in MIR space missions.

A versatile and simple to use biomedical instrumentation for noninvasive examinations of cosmonauts at the Russian MIR space station was developed. It consists of a comfortable sensor jacket to assess signals from the body surface, a precision hand dynamometer to produce muscular and cardiovascular loads, and a small interactive microprocessor unit that controls the examination and stores measurement data. The sensor jacket includes highly sensitive piezo-resistive accelerometers, pulse sensors, an ECG system, and a skin-mountable mechanical vibrator. The functionality of this instrumentation was evaluated during long-term space flights and also proved very useful in laboratory and clinical studies.

Cardiovascular Physiological Phenomena↗
PubMed1989

[Comparison of heart rate to lactate threshold and to Conconi's threshold in children].

The heart rate (HR) at the lactate threshold was determined on a treadmill in 59 children with an average age of 11.8 years. 45 minutes later, they had to go through a vita maxima test on a bicycle ergometer. The load was increased stepwise by 10 Watt/min. During the tests HR was registered continually and stored every 5 seconds. In 52 children the characteristic break point was evident; in 7 children no break point could be found - in 2 children, because they had stopped the exercise before reaching the lactate threshold, and in 5 children because their HR increased linearly from the beginning until the end of the load application. HR at the break point correlated very strongly with HR at the lactate threshold (r = 0.99). Therefore the authors are of the opinion that the introduced modification of the Conconi test can substitute the invasive lactate threshold determination in children.

Child↗
PubMed1988

A noninvasive method of determining the anaerobic threshold in children.

In 72 11-year-old male and female children the anaerobic threshold (AT) was determined on a treadmill with the invasive method of the lactate test. After a break of 45 min an alternative method for determining AT on a bicycle ergometer was used. A loading method with an increment of 10 W/min was chosen. At AT a characteristic deflection from linearity in the heart rate could be recorded. The comparison between the heart rate at the point of deflection and the heart rate at AT determined invasively shows an outstandingly high correlation (r = 0.98; P less than 0.0001). Consequently, the authors came to the conclusion that it is possible to use the deflection from linearity of the heart rate in tests on bicycle ergometer for training optimization in 11-year-old children if the proper degree of load increase is chosen. This simple method can substitute a more laborious invasive way of determining AT.

Child↗
PubMed1987

[Local hyperthermia of malignant brain tumors].

In glioblastoma multiforme and high-grade astrocytomas the following procedure has been implemented to try and prevent recurrence: after extirpation of the tumour its bed is lined with metal powder and the patient's head is exposed to a high-frequency magnetic field every 4 weeks. As a result the temperature is raised by induction to +45 degrees C at the boundary between metal and brain tissue. This ought to be sufficient to prevent tumour recurrence. Varied results were achieved using this technique in 103 patients.

Brain Neoplasms↗
PubMed1979

[High voltage power station to study the influence of the DC-field with superimposed AC-field on humans (author's transl)].

Due to the great progress in electrical engineering man is exposed to electric fields in a high degree. However, the effect of the electric field has not been definitely cleared up till now. The following parameters are of decisive importance: Field intensity- Frequency-Shape of curve-Boundary conditions. As scientific investigations can only be reproduced and accepted when the experimental conditions are clearly defined, a station meeting these requirements has been developed. It consists of Testing room: Electric screen damping higher than 80 dB-Magnetic screen damping higher than 45 dB-large, cased ceiling electrode. Control room: Same as testing room, but no screening. High voltage generator: a) DC-Voltage 0-20 kV ripple & noise less than 0.01%; b) Alternating voltage 0-300 Vss frequency 5 Hz-50 kHz; c) combination of a) and b).

Clinical Trials as Topic↗
PubMedDate not supplied

[Evaluation of semen by electronic spermcounter].

The new electronic spermcounter was developed to make andrological routine work easier. The apparatus is a complete microcomputer and has three main functions: The counter function allows to determine the number of spermatozoa and round cells at the same time. The morphological function allows the detailed morphological analysis of stained spermatozoa specimen within a reasonable time. Besides the determination of normal and pathlogical forms a more exact differentiation of the respective pathological spermatozoon is possible. The timer function guarantees the exact timing of the evaluation of sperm motility. We judge the motility immediately after ejaculation and 30, 60, 120, 240 minutes later. Using the electronic sperm counter in the andrological routine laboratory and for detailed morphological studies we observed an improvement of the quality of our results and a remarkable saving of time. It is evident, that the spermcounter is a valuable equipment for all institutions performing investigations on sperm, of instance clinical and practical andrologists, veterinarians and scientists working in the field of reproduction.

Humans↗