摘要:

Endogenous Rhythms in Mimosa pudica L. Leaf Movements.

ISSN:0022-1945    

DOI:10.1080/09291017709359549

出版商:Taylor & Francis Group    

年代:1977

数据来源: Taylor

摘要:

Four Thoroughbred mares (no. 1–4) were maintained under constant temperature (24°C) and controlled light (L/D:12/12 with lights on at 06.00 hr) conditions. They were fed and watered ad libitum with fresh feed and water given at 09.00 hr. After a 45‐day pre‐conditioning period, blood samples were obtained by veinipuncture at 4‐hr intervals for 14 days to determine circadian and day‐to‐day variation. The horses exhibited a circadian rhythm with maximum values attained at about 12.00 hr, however, there are periods of days in which no rhythm is distinguishable. Ultradian rhythms with mean periods of 105 to 128 and 24 to 31 min are superimposed upon the circadian rhythm. The individual rhythms are quite variable from horse to horse and within the same horse. During periods of decline in plasma cortisol with metabolic half‐lives of approximately 70 min, secretion of cortisol was very low or had ceased. During periods of increasing plasma concentration, secretion was occurring at a faster rate than degradation. Rapid decreases in plasma concentration (metabolic half‐life of approximately 30 min) was accompanied by a rise in specific activity indicating cortisol with a high specific activity was entering the plasma pool from other storage pools.

ISSN:0022-1945    

DOI:10.1080/09291017709359550

出版商:Taylor & Francis Group    

年代:1977

数据来源: Taylor

摘要:

Enzymatic activity of five lysosomal hydrolases: acid p‐nitrophenyl phosphatase (EC 3.1.3.2), acidβ‐glycerophosphatase (EC 3.1.3.2), arylsulphatase (EC 3.1.6.1),β‐galactosidase (EC 3.2.1.23) andβ‐N‐acetylhexosaminidase (EC 3.2.1.30) was studied in the supernatants of homogenates of hearts of unirradiated mice, serving as controls, and a group of U.V.‐irradiated mice.

ISSN:0022-1945    

DOI:10.1080/09291017709359551

出版商:Taylor & Francis Group    

年代:1977

数据来源: Taylor

摘要:

In order to detect hidden periodicities in glycolytic oscillations and to estimate period lengths the interactive program system TIMESDIA was applied. This program system contains a collection of mathematical procedures apt to the above purpose.

ISSN:0022-1945    

DOI:10.1080/09291017709359552

出版商:Taylor & Francis Group    

年代:1977

数据来源: Taylor

摘要:

Enright's theory, which explains entrainment as periodically repeated phase response, is applied to Wever's self‐sustained oscillation model of are circadian rhythm and tested by computer simulation. Ranges of phase response and entrainment are compared and the oscillatory behaviour is shown in the phase diagram for the cases of phase response and entrainment. It is shown that Enright's theory is not valid for self‐sustained oscillations in general, but it need not necessarily fail in case of the biological circadian rhythm.

ISSN:0022-1945    

DOI:10.1080/09291017709359553

出版商:Taylor & Francis Group    

年代:1977

数据来源: Taylor

摘要:

A mathematically sound technique by which circadian rhythms may be detected is that of periodogram analysis. It is necessary, however, in applying this method, to ensure that the observations are equally spaced. In physiological experiments, it is often found that some of the observation points are periodically missing. A modified periodogram technique is defined and its usefulness in cycle detection is demonstrated by means of both simulated and real data.

ISSN:0022-1945    

DOI:10.1080/09291017709359554

出版商:Taylor & Francis Group    

年代:1977

数据来源: Taylor

ISSN:0022-1945    

DOI:10.1080/09291017709359548

出版商:Taylor & Francis Group    

年代:1977

数据来源: Taylor