Biomedical subjects

D Kropveld

Publications and source records attributed to D Kropveld.

4 recordsLinked to original sources

PubMed1993

Doppler radar device as a useful tool to quantify the liveliness of the experimental animal.

The Doppler radar device which is described here is shown to be a reliable and accurate device to quantify the liveliness of an experimental rat. During recording the animal did not seem to be disturbed in any way by the device. It could stay in its normal cage, move freely, walk around and eat and drink ad libitum. Measurement did not require extra light, sound or other stimuli. Interpretation of the data was easy. The computer which samples the Doppler radar output signal generates activity curves which were easily interpreted for different ranges of vitality, varying between high liveliness and apnoea or cardiac arrest. The apparatus is low priced, and simple to build and use.

Animals↗

PubMed1988

Digital nerve somatosensory evoked potentials and flexor carpi radialis H reflexes in cervical disc protrusion and involvement of the sixth or seventh cervical root: relations to clinical and myelographic findings.

Peak latencies of somatosensory evoked potentials (SEPs) from nerves of the first digit (digit 1-SEP), 39 controls, and third digit (digit 3-SEP), 47 controls, and indicated for Erb's point, second cervical vertebra (Cv2) and contralateral cortical hand area correlated significantly with arm length. Single regression analysis for arm length for Erb's potentials and the Cv2 potential in digit 1-SEP, and multiple regression analysis for arm length and age for the Cv2 potential in digit 3-SEP, the cortical potentials and flexor carpi radialis H reflex were used for demonstration of root C6 or C7 pathology. Upper crossing of +3 S.D. was defined as abnormal. The combined examination yielded abnormalities in 81% of our 22 patients operated for compression of root C6 or C7 due to cervical disc protrusion. A minority of the patients showed multiple positive correlations between symptoms and electrophysiologic and myelographic findings. In others only one or the other investigative procedure provided confirmatory information, while, in a notable number (6 patients), these approaches revealed abnormalities when there were no or non-specific symptoms. The presented electrophysiological investigations are useful to determine the presence and severity of root C6 or C7 compression as well as the functional relevance of a myelographic abnormality.

Adult↗

PubMed1983

A computerised EEG-analyzing system for small laboratory animals.

The experimental setup, including instrumentation and software packaging, is described for the use of a minicomputer as an on-line analyzing system of the EEG in rats. Complete fast Fourier transformation of the EEG sampled in 15 episodes of 10 s each is plotted out within 7 min after the start of registration of the EEG signal. The influence of high voltage spikes, spindles and baseline drift on the power density spectrum is shown and a method of clipping is presented that excludes these kinds of artefacts. The normalized standard error of the power density estimate is determined by the smoothing procedure and is at maximum 26%.

Animals↗

PubMed1983

Quantitative analysis of EEG power spectra in experimental hepatic encephalopathy.

During galactosamine-induced acute liver failure in white male Wistar rats, EEG was recorded at regular intervals. Spectral analysis was done as described by Kropveld and co-workers in 1983. The specificity of the anomalies in the power-density spectra is tested by comparing the changing patterns with those caused by several pharmaceutical agents--ether, diazepam, pentobarbital. Quantification of the observed anomalies is discussed.

Animals↗