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181.
Polygraphic recordings of wake and sleep were performed on 10 partly bed-ridden, severely deteriorated patients with senile dementia. Compared with healthy elderly persons these subjects showed less SWS (slow wave sleep, characterized by high amplitude, slow EEG waves), less REM sleep (rapid eye movement sleep, usually accompanied by dream activity) and poorly organized stage 2 sleep (no sleep spindles, i.e. phasic EEG activity with a frequency of 12-14 Hz). Six of the 10 patients had no dominant alpha rhythm during wakefulness; this seemed to be related to their more deteriorated clinical state, to still less SWS and REM sleep and more time spent in stage 2. The basic NREM-REM cycle of sleep, i.e. the regular alternation between non-REM- and REM-periods, could still be distinguished, however, and showed similar average temporal characteristics as in healthy old and younger people. Similarly, although sleep was severely fragmented in most patients and many sleep episodes occurred during the day, the day-night alternation of wakefulness and sleep was maintained in the sample as a whole. 相似文献
182.
F. Markwardt J. Stürzebecher H. Müller 《Cellular and molecular life sciences : CMLS》1984,40(4):373-374
Summary Glandular kallikrein can be temporarily acylated at the active centre by 4-amidinophenyl benzoates. The time course of reactivation depends on the nature of the acyl group introduced. Benzoyl kallikrein was used as a delivery system for kallikrein in vivo. In rabbits, bolus injection of the acylated enzyme caused a long-lasting drop in blood pressure due to sustained kinin liberation. 相似文献
183.
Glandular kallikrein can be temporarily acylated at the active centre by 4-amidinophenyl benzoates. The time course of reactivation depends on the nature of the acyl group introduced. Benzoyl kallikrein was used as a delivery system for kallikrein in vivo. In rabbits, bolus injection of the acylated enzyme caused a long-lasting drop in blood pressure due to sustained kinin liberation. 相似文献
184.
The basis of peripheral blood lymphopenia observed in patients with chronic alcoholism and liver disease was investigated by examining the effect of sera of these patients on in vitro transformation of normal human peripheral blood lymphocytes. A positive correlation was demonstrated between the serum inhibition of phytohaemagglutinin- and pokeweed mitogen-induced transformation and the degree of lymphopenia. Thus serum factors may contribute to the observed lymphopenia by inhibiting lymphocyte production in vivo. 相似文献
185.
Mutagenicity of melanin from human red hair 总被引:1,自引:0,他引:1
Z. P. Harsanyl P. W. Post Jeannie P. Brinkmann M. R. Chedekel Rose Marie Deibel 《Cellular and molecular life sciences : CMLS》1980,36(3):291-292
Summary TheSalmonella typhimurium histidine reversion test of Ames et al. was used to demonstrate that pheomelanin, the red-brown polymeric pigment produced in human skin and hair, becomes mutagenic after exposure to long wave-length UV-light; a finding consistent with the UV-induced somatic mutation hypothesis for the origin of freckles and the high susceptibility of redheads and blonds to sunlight-induced skin cancers.Acknowledgments.S. typhimurium strains were kindly provided by Dr Bruce N. Ames. Z. Harzanyi was supported by NIEHS grant 00675-03 and an Andrew W. Mellon Teacher-Scientist Award. M. Chedekel thanks The Ohio State University Graduate School for financial assistance. 相似文献
186.
Zusammenfassung Die Wirkung ultravioletter Strahlung von 280 nm Wellenlänge auf die Ionenströme der Membran des Ranvierschen Schnürringes wurde im «voltage clamp»-Verfahren gemessen. Die «Kanäle» für Natrium werden im Sinne eines Ein-Treffer-Ereignisses blockiert. Die daraus resultierende Herabsetzung des maximalen Natrium-Einstromes ist eine Exponentialfunktion der Bestrahlungsdosis. Der Kaliumstrom wird bei dieser Wellenlänge nur wenig beeinflusst.
Supported by Deutsche Forschungsgemeinschaft, Sonderforschungsbereich 38 Membranforschung. 相似文献
Supported by Deutsche Forschungsgemeinschaft, Sonderforschungsbereich 38 Membranforschung. 相似文献
187.
Zusammenfassung Die histochemische Fluoreszenzmethode wird zum Studium der Nervenzellen des Gehirnstammes der Ratte angewandt. Die erhebliche Zunahme des Dopamins, hervorgerufen durch die Injektion eines peripher wirkenden Dekarboxylase-Hemmstoffes zusammen mitl-DOPA, wird im Gehirn verfolgt und gefunden, dass serotonergische Neuronen imstande sind, Catecholamine aufzunehmen.
This work has been supported by the Clinical Research Center for Parkinson's and Allied Diseases, grant No. NS05184. 相似文献
This work has been supported by the Clinical Research Center for Parkinson's and Allied Diseases, grant No. NS05184. 相似文献
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