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101.
(3H)-Ouabain binding to liver and kidney preparations was utilized to estimate the number of Na+, K+-ATPase enzyme units in livers and kidneys from rats fed 2% corn oil supplemented or fat-free diets. The specific (3H)-ouabain binding in liver and kidney preparations from fatty acid deficient rats was increased approximately 40%, but the affinity of the binding sites for ouabain (Kd-value) remained unchanged. The increased concentration of Na+, K+-ATPase enzyme units observed in the essential fatty acid deficient rats may contribute to the reduced body fat accumulation and elevated heat production observed in these animals.  相似文献   
102.
Summary A rotator culture method is described which provides a continuous flow of oxygenating gas to cultures in rotating bottles. The system maintains constant O2 and CO2 levels in the culture medium throughout the incubation period. It also provides a more stable pH than systems with sealed culture bottles.Acknowledgments. We would like to thank Mr B. Secker, Mr C. Hellon and Mr S. J. Ellis, of the Physiological Laboratory workshop, for constructing the rotator apparatus. We also thank the Medical Research Council, London, for financial support for the project.  相似文献   
103.
Summary Corpora allata fromOncopeltus fasciatus incubated in vitro in medium containing 10–5.35 M (1 g/ml) of precocene II lose their ability to secrete juvenile hormone when reimplanted into last instar larvae.Acknowledgments. We thank Mr K. Dorn, Mrs L. Dolezal, Mrs V. Nötzli-Graf, Mr K.H. Trautmann and Mr A. Schuler for technical help, Dr W. Vogel and Dr A. Dübendorfer for valuable discussions.  相似文献   
104.
Summary Trans-4-hydroxy-3-methoxycinnamic acid (ferulic acid, FA) antagonized the effect of exogenous androgens on the ventral prostate (VP) in castrated rats as well as the effect of endogenous androgens in intact rats. FA, however, had no effect on the seminal vesicles (SV) and levator ani muscle (LAM), nor oestrogenic effect in female rats and mice. FA did not antagonize the receptor binding of testosterone nor inhibit the conversion of testosterone into 5-dihydrotestosterone (DHT).Supported in part by the project fund (grant 53-403) of Kawasaki Medical School.The authors would like to thank the Central Laboratory, Sankyo Pharmaceutical Co., Tokyo, for supplying 19-nortestosterone-17-ferulate.  相似文献   
105.
Summary The paper describes a hexagonal array of nuclear pores in a non-redundant region of the nuclear envelope underlying the basal surface of the rat spermatozoon head. It is concluded that intranuclear material protruding through these pores is the cause of the characteristic rows of circular bumps found in surface replicas of this region.  相似文献   
106.
Summary The serum activities of aspartate aminotransferase, alanine aminotransferase, -hydroxybutyrate dehydrogenase and creatine phosphokinase have been measured in the African elephant. In general, the values were broadly comparable with those of man except that alanine aminotransferase was much lower and creatine phosphokinase higher. No variation due to age, sex, season or location was observed.  相似文献   
107.
108.
The DNP fibres gamma-irradiated under aerobic condition showed a reduction of their diameter, while no remarkable changes were observed in the DNP fibres irradiated under hypoxic condition by scanning electron microscopy.  相似文献   
109.
T Dalton 《Experientia》1976,32(11):1421-1423
5-Hydroxytryptamine creatinine sulphate loses its biological activity when maintained at room temperature. The loss of 5-HT activity (in stimulating sodium transport across frog skin) is greater than the loss of creatinine sulphate activity (inhibition of sodium transport).  相似文献   
110.
Summary Adenylate kinase activity of intact mitochondria is strongly inhibited by Ap5A, i.e.p 1,p 5-Di (adenosine-5-) pentaphosphate, whereas oxidative phosphorylation is not affected. Therefore, Ap5A is a useful tool to distinguish between oxidative and non oxidative ATP generating reactions.Acknowledgment. The generous support of Prof. Dr.Walther Lamprecht is gratefully acknowledged. J. L. thanks the Stipendienfonds des Verbandes der Chemische Industrie for a scholarship.  相似文献   
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