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21.
T. Stojanovié B. M. Djuričić B. B. Mršulja 《Cellular and molecular life sciences : CMLS》1980,36(12):1348-1350
Summary The activity of (Na++K+)-ATPase and acetylcholine esterase were folloed in rat brain cerebral cortex, caudate, thalamus, hippocampus and medulla after i.v. administration of physostigmine. Both enzymes were found to be inhibited in a dose-dependent manner. The most pronounced inhibition of (Na++K+)-ATPase was found in caudate. where the highest activity of acetylcholine esterase is found.These studies were supported by a grant from the Union of Science of Republic Serbia, No. 40404-14. 相似文献
22.
D. Sabourault Françoise Bauché Y. Giudicelli J. Nordmann R. Nordmann 《Cellular and molecular life sciences : CMLS》1981,37(3):227-229
Summary After 3 weeks of continuous ethanol intoxication by inhalation, the maximal number and affinity of the -and -receptors of rat heart were unchanged. These data indicate that adrenergic receptor disturbances are not involved in the mechanism of chronic ethanol-induced triglyceride deposition in the heart.Acknowledgments. This work was supported by grants from the Institut National de la Santé et de la Recherche Médicale. We wish to thank Mr M. Clément for skilled technical assistance in performing chronic ethanol inhalation treatments. 相似文献
23.
The influence from carotid baroreceptors on portal immuno-reactive glucagon and insulin levels and on arterial plasma glucose concentration was studied in vagotomized cats by sectioning of the sinus nerves. Such a complete elimination of the afferent baroreceptor discharge caused a prompt and pronounced increase in the glucose and glucagon levels, whereas the insulin concentration significantly decreased. The role of vascular barorecptors in the hyperglycemic response to hemorrhage is discussed. 相似文献
24.
Non-mendelial female sterility in Drosophila melanogaster: demonstration of an inducer chromosome 4]
A Pélisson 《Comptes rendus des séances de l'Académie des sciences. Série D, Sciences naturelles》1977,284(23):2399-2402
Crosses between two classes of Drosophila melanogaster strains (reactive and inducer) may lead to partially sterile F1 females. This sterility, called S.F. sterility, can be characterized by its physiological features. It appears to be the result of an interaction between two factors: "R" brought into the initial croos by the reactive mother and "I" by chromosomes of the inducer father. Except for chromosome 4, each chromosome of the well known inducer strains may carry the I factor (inducer chromosomes). The present results provide evidence for the presence of an inducer fourth chromosome in the inducer strain Nagasaki. 相似文献
25.
S André N Farjaudon C Pareyre E Séguin 《Comptes rendus des séances de l'Académie des sciences. Série D, Sciences naturelles》1979,288(14):1095-1097
Comparing cytotoxicity of tubulosine and of six newly synthesized pseudo-tubulosines in the Allium test, we have characterized all the current features of protein inhibition. Nevertheless cytotoxicity of the six pseudotubulosines is much weaker. Furthermore, "floating poles anaphasis", a disturbance characteristic of the action of tubulosine, has been found with a lesser intensity with the other compounds. 相似文献
26.
A Nu?ez-Roldan A Arnaiz-Villena G Nu?ez-Ollero 《Comptes rendus des séances de l'Académie des sciences. Série D, Sciences naturelles》1979,288(23):1719-1720
In 10 sibships of haemophilic A patients, every one including 1 haemophilic brother with an antibody to factor VIII and 1 haemophilic brother without antibody, pattern of HLA segregation was analysed. All sibships were HLA haploidentical or different and not HLA identical. This fact suggested a linkage between the major histocompatibility complex and an "Ir" gene to factor VIII. 相似文献
27.
It was shown that, in physiological concentrations, insulin enhances, in vitro, the immunological phagocytosis of sensitized sheep erythrocytes by cultured mouse peritoneal macrophages. Insulin seems to stimulate macrophage phagocytosis as a cholinomimetic agonist by increasing the intracellular levels of cyclic GMP. 相似文献
28.
The hyperthermic effect of a bacterial pyrogen has been studied in rabbits pretreated or not with p-chlorophenylalanine or 5, 6-dihydroxytryptamine. The results obtained indicate that a selective reduction of cerebral 5-hydroxytryptamine levels by these drugs do not significantly affect pyrogen hypertermia. 相似文献
29.
将Logistic映射产生的混沌序列作为载波,利用序列具有的良好相关特性,提出了一种图像保密通信方案。计算机仿真结果表明,只要收发双方使用相同的初值条件,即使在有一定噪声的情况下也能正确地进行图像传输,而初值的微小差异将导致通信失败,表明混沌序列用于保密通信具有很高的安全性能,同时方案具有很强的抗干扰能力。对图像恢复质量进行了评估,并给出了误比特率与码片长度的经验公式。 相似文献
30.
传统的火箭飞行数据处理方法是使用α-β-γ数字滤皮离线处理,对飞行数据采样信号的第1点、第2点不进行滤波估值,第3点开始逐个进行估值、预测、校正。该方法需要消耗大量的时间,并且滤波后信号的残留噪声仍然较多。针对此问题,经过大量的数值实验和理论分析,发现用小波方法实时处理火箭飞行数据效果较好,比较两种结果,证明无论是滤波后信号的残留噪声还是消耗的时间上小波方法都优于α-β-γ滤波,且实现了数据的实时处理功能,应用前景好。 相似文献