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931.
The sympathetic influences on the rabbit unstimulated parotid gland were studied. The experiments were carried out in anaesthetized rabbits with the Stenon aduct cannulated. Direct stimulation of the superior cervical ganglion elicits variable salivary flows. The high amylase content in the saliva points to a sympathetic secretory action upon acinar cells. The administration of alpha-adrenergic blocking agents (dihydroergotamine, phentolamine and phenoxybenzamine) clearly reduces and even abolishes the effect of the sympathetic stimulation upon flow. The administration of a beta-adrenergic blocking agent (propranolol) slightly reduces the sympathetic action. However the amylase activity is greatly reduced. All this suggests that the secretory effects on the fluid fraction should predominantly be alpha-adrenergic while on the secretion of enzymes the beta-receptors should play an important role. 相似文献
932.
P Morméde R Dantzer 《Comptes rendus des séances de la Société de biologie et de ses filiales》1979,173(3):569-575
Behaviour and plasma corticosteroid levels were investigated in pigs preloaded with 50 to 200 mg/kg 1-tryptophan. The treatment did not influence reactions to frustation and had no effect on continuous avoidance responding. However the adrenal response to the stress of new environment concomitant with delivery of unavoidable shocks was decreased (fig. 1), as well as the behavioural response to a fear signal superimposed on a continuous avoidance paradigm (fig. 2). These results point out relatively specific psychotropic effects of a tryptophan load in pigs. 相似文献
933.
H Maisin A Van Evercoren M A Anckaert B M de Coster 《Comptes rendus des séances de la Société de biologie et de ses filiales》1979,173(4):832-834
We have studied the recovery for mice bone marrow cells after fractionated irradiation of the whole body. The additional dose (Dr) to obtain a given biological effect if the irradiation is split in two equal subfractions (2 Di) separated by a short interval of time (i) is 40 rad per day when the interval of time between the two irradiations is lengthened of one day. 相似文献
934.
P de Micco J Tamalet 《Comptes rendus des séances de la Société de biologie et de ses filiales》1979,173(1):110-116
A studying method of viruses induced cell-fusion is described, using monolayers of Vero monkey cells. Nature and density of cells and infection multiplicity are studied. The sensibility is equal to 4 hemagglutining units of Senda? and accuracy about +/- 3 % of polykaryocytosis. Quantification. comparison and kinetics study of cell-fusion are allowed by this method which may lead to systematic and routine exploration of cell-fusion ability of biological extracts from slow degenerative diseases of the human central nervous system. 相似文献
935.
936.
937.
N Moschonas E de Boer F G Grosveld H H Dahl S Wright C K Shewmaker R A Flavell 《Nucleic acids research》1981,9(17):4391-4401
938.
The problem of estimating an unknown transient signal, given an ensemble of waveforms, in which this signal appears as a nonrandom component in the presence of additive noise is considered. This problem is solved by generalizing the method of a posteriori Wiener filtering. In the new method, the ensemble average is filtered by a time-varying system which is based on estimated time-varying power spectra of signal and noise. The nature of this system, and the computational procedures involved, are discussed in detail. A software package for time-varying filtering is briefly described. Application of the method is illustrated by a simulation example, which also provides a comparison to time-invariant a posteriori Wiener filtering. 相似文献
939.
Summary Quantitative assays of steroid sulphatase in XX males have shown that some individuals have two functional loci, and others only one. Two affected cousins, who cannot share the same X-chromosome, nevertheless have male levels of steroid sulphatase, suggesting functional abnormality of the X chromosome.The hypothesis is advanced that these and other unusual features of X-chromosome function in some XX males, could be explained if such cases were due to an autosomal mutation, exercising its effect by causing abnormal inactivation of a subterminal area of Xp which normally escapes the inactivation process. 相似文献
940.
Summary Two new cases of the D.O.O.R. syndrome are reported. The patients described showed most of the characteristics described by Cantwell (1975) and some others that may represent additional clinical findings of this rare syndrome. 相似文献