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591.
592.
The occurrence of a circadian rhythm in the concentration of circulating atrial natriuretic peptide (ANP) is not clearly established. To investigate diurnal changes, plasma levels of ANP were measured at 10-min intervals for 24 hours in six normal volunteers. The subjects were studied once during a normal sleep-wake cycle and once during a cycle with a shifted sleep period. They received continuous enteral nutrition from 8 hours preceding the experiment until the end of the experiment, throughout this time the subjects remained in a supine position. The mean ANP levels did not differ significantly between the sleep periods and the periods spent awake in either of the protocols, which provides evidence of a lack of a sleep-related influence of ANP. A significant linearity of the mean ANP profile was observed, smoothing out the transient and randomly occurring fluctuations in individual ANP concentration. These results lead to the conclusion that ANP secretion is neither under the control of endogenous circadian rhythmicity nor is it affected by sleep-regulatory mechanisms. 相似文献
593.
R S Saini 《Biochemistry and experimental biology》1977,13(2):215-216
Imago of Tenebrio, Dermestes (Coleoptera) and Lepidopterous caterpillars Pieris and Galleria were observed for the general physiology of the cryptonephric Malpighian tubules. Injection of dyes were made. The dyes were taken only by the free portion of the Malpighian tubules. Reassociated Malpighian tubules do not take dyes from the haemoly mph. They are secretory, but not excretory. The perinephric membrane in the Lepidoptera is impermeable to the dyes. 相似文献
594.
Circadian time structure in shift working Indian nurses was studied. In shift workers desynchronization between circadian rhythms in different physiological variables was observed. Circadian amplitudes of oral temperature, pulse and random add speed rhythms decreased significantly in shift workers as compared to control subjects. Circadian mesors of performance rhythms increased significantly in shift workers indicating that the time taken by them was more for performing the tasks. It can be concluded that the subjects studied herein are intolerant to shift work and amplitude decrement may be considered as a chronobiologic index to determine the tolerance of individual workers to shift work. 相似文献
595.
A simple, rapid and efficient procedure is presented for the purification of human prostatic acid phosphatase (orthophosphoric-monoester phosphohydrolase (acid optimum), EC 3.1.3.2) to homogeneity. The method employs two steps suitable for use with large quantities of material, followed by chromatography on concanavalin A-Sepharose as its sole column step. The procedure also permits the recovery of purified enzyme in higher yields than earlier methods. 相似文献
596.
R. P. Tiwari V. Mittal G. Singh T. C. Bhalla S. S. Saini D. V. Vadehra 《Folia microbiologica》1986,31(2):120-123
The effect of saturated and unsaturated fatty acids on aflatoxin production was studied in a synthetic medium. The aflatoxin production decreased (10-75%) in the presence of lauric acid and palmitic acid but the addition of behenic and sebacic acid stimulated aflatoxin production by 125-541%. Linolenic and linoleic acids effected aflatoxin production and mycelium growth. An 34-fold increase in aflatoxin production was observed with 50 mM linoleic acid. An inverse relationship was observed between aflatoxin production and mycelium mass, irrespective of the nature of the fatty acid. 相似文献
597.