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991.
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Summary Sham-pinealectomy, performed under different light conditions in newborn and adult rats, is followed by changes of pineal activity resulting in variations of melatonin content. The pineal glands of rats sham-operated under white light produce significantly less melatonin. In contrast, glands of rats operated on under red light show a melatonin content corresponding to that of intact rats. This result implies that normal white light causes a disturbance in melatonin production by a non-retinal pathway. 相似文献
994.
V. Pliška M. Meyer-Grass N. Bersinger L. Carlsson P. Melin H. Vilhardt 《Cellular and molecular life sciences : CMLS》1980,36(10):1145-1146
Summary Lysine vasopressin tritiated at meta position of tyrosine (1.9 Ci/mmole) decomposes during a long storage period, mainly as a result of radiolysis. The loss of specific activity by isotopic exchange with water is slow. The nonlabelled peptide undergoes only very minute decomposition (polymerization). Specific radioactivity declines with a half life of 47.4 months.Acknowledgments. This research was supported by Swiss National Science Foundation, grant No.3.040.76 (V.P.). Some of the measurements (years 1969–70) were carried out at Roche Institute of Molecular Biology, Nutley, N.J., USA. 相似文献
995.
A. V. Champakamalini R. Appaswami Rao 《Cellular and molecular life sciences : CMLS》1977,33(4):499-500
Summary The effect of administering barbital sodium, phenobarbitone or butobartitone during pregnancy was investigated in rats. The study shows that these bartiturates affect the litter-size and retard the foetal growth markedly. The embryos produced are significantly undersized.Acknowledgments. The authors wish to express their gratitude to Prof. M. R. Rajasekar Setty for the encouragement received and CSIR, India, for the award of a Research Fellowship to A. V. Champakamalini. 相似文献
996.
Summary Both aspartate and alanine aminotransferase levels increased in digestive gland, foot and mantle on aestivation. The free amino acids and pyruvic acid also increased in all tissues. The significance of these changes is discussed in relation to gluconeogenesis.Acknowledgment. The authors thank Professor K.S. Swami, Head, Department of Zoology, for encouragement and Mr I. Kabeer Ahamed for his help. 相似文献
997.
A. C. Mathur Ajay K. Sharma V. Verma 《Cellular and molecular life sciences : CMLS》1980,36(2):245-246
Summary Feeding male houseflies with 0.075% aristolochic acid obtained from the plants of the genusAristolochia induced sterility. High condensation of chromosomes, and breakages, have been shown to be responsible for sterility. When onion roots were exposed to aristolochic acid similar chromosomal aberrations were noticed in cells at the tip.Authors are thankful to Prof. Dr G. Rücker (Universität Bonn) for a generous gift of aristolochic acid. 相似文献
998.
Summary Short term in vitro experiments on the influence of the extracts of corpora allata and brain from the termite queenOdontotermes assmuthi on the lipid release from the fat body into the haemolymph indicated that the extract of corpora allata does not influence the lipid mobilization, whereas the brain extract increases the free fatty acid level in the haemolymph. It is believed that the brain extract stimulates triglyceride hydrolysis in the fat body. 相似文献
999.
1000.
H V Van Kha Y Le Maho M Cagnard 《Comptes rendus des séances de l'Académie des sciences. Série D, Sciences naturelles》1979,289(13):955-958
In fed geese, plasma levels of glucose and alanine were 1.9 g.l-1 and 560 mumol.l-1, respectively. During a long fast (40 days), plasma glucose and alanine were maintained at a high level (1.5-1.8 g.l-1 and 370-540 mumol.l-1, respectively). Plasma level of acetoacetate was very low (40 mumol.l-1); by contrast, plasma level of beta hydroxybutyrate reached very high values (20 mmol.l-1) after about 20 days of fasting, then it decreased. Plasma levels of lactate and pyruvate decreased along the course of the fast, from 2 500 to 2 000 mumol.l-1 and 220 to 170 mumol.l-1, respectively. 相似文献