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71.
Yu. V. Burov S. E. Metkalova A. É. Kustov G. V. Petrov V. V. Shul'govsky 《Neurophysiology》1993,25(3):156-160
In twoMacaca rhesus monkeys that received repeated N-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) injections (single dose 0.2 mg/kg, i.m.; cumulative dose 11.2–13.3 mg), changes in characteristics of spontaneous saccadic eye movements and vestibulo-ocular reflex (VOR) were evaluated. With the development of severe behavioral disturbances, amplitude of spontaneous saccadic eye movements gradually decreased. Pronounced changes in duration of saccadic eye movements, frequency of spontaneous saccades, and their pattern were observed. No changes in parameters of VOR slow component were recorded, but high total MPTP doses suppressed fast phase of the reflex.Neirofiziologiya/Neurophysiology, Vol. 25, No. 3, pp. 184–190, May–June, 1993. 相似文献
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Yu. S. Ravkin S. M. Tsybulin S. G. Livanov K. V. Toropov V. N. Kuranova V. P. Starikov S. V. Chesnokova 《Contemporary Problems of Ecology》2008,1(5):568-573
For the entire territory of West Siberia, including its plain and mountainous parts, two maps were constructed for populations of amphibians together with reptiles, and of birds. Communities of these classes of vertebrates differ from one another in their spatial differentiation. The differences are demonstrated for the plain and mountainous territories considered jointly and separately. 相似文献
74.
D G Warnock W C Yang Z Q Huang E J Cragoe 《The Journal of biological chemistry》1988,263(15):7216-7221
Amiloride is a reversible inhibitor of the Na+/H+ antiporter which acts at the external aspect of the transport system. The kinetics of inhibition of the Na+/H+ antiporter with amiloride have been controversial, with the usual finding of simple competitive inhibition, but with other reports of mixed and noncompetitive inhibition of the transporter by amiloride. The present experiments demonstrate that the chloride content of the external transport buffer affects the kinetics of amiloride inhibition. Either simple competitive or mixed inhibition by amiloride was observed in the same vesicle preparations depending on the presence of chloride or gluconate in the buffer. The effect of chloride on the inhibitory effect of amiloride was dependent on the concentration of chloride and amiloride. Similar effects were observed with more potent analogues of amiloride. These findings suggest that the external aspect of the antiporter has a site or sites at which the inhibitory effects of amiloride on the Na+/H+ antiporter can be modified by chloride, even though chloride has only slight effects on the kinetics of the Na+/H+ antiporter in the absence of amiloride. 相似文献
75.
The clearance in vivo of rat C-reactive protein (CRP) was studied: (i) in the whole animal and (ii) by using a rat liver perfusion system. Rat CRP is a glycosylated serum protein containing a complex-type biantennary carbohydrate structure on each of its five subunits. The half-life of rat asialo CRP was approximately 5 min. More than 75% of the radioactivity associated with rat asialo CRP and asialo alpha 1-acid glycoprotein (AGP) was recovered in the liver. A small amount of radioactivity (0.8%) associated with rat CRP and rat asialo CRP was found in the lungs. Competitive inhibition of the clearance of 125I-labelled rat asialo CRP from the circulation by asialo AGP was dose dependent, and resulted in a corresponding decrease in the recovery of radioactivity associated with rat asialo CRP in the liver. This indicated that asialo AGP and rat asialo CRP were cleared by the hepatic asialoglycoprotein receptor. This observation was confirmed when the clearance of rat asialo CRP was studied using a rat liver perfusion system. Using this system, the clearance of rat asialo CRP and asialo AGP from the perfusate was inhibited by N-acetylgalactosamine, but not by phosphorylcholine, a ligand through which most of the CRP reactions are mediated. This study provides an example of a circulating serum glycoprotein containing a biantennary carbohydrate structure that is cleared by the asialoglycoprotein receptor. 相似文献
76.
The possibility of the use of small amounts of chitosan for defatting and clarification of protein solutions prepared by enzymatic hydrolysis was tested. The following treatment conditions were shown to be optimal: a chitosan concentration range, from 1.0 to 1.5 gram per kilogram raw weight; pH of the precipitation medium from 8.0 to 8.5; and duration of the incubation of the protein hydrolysate solution with chitosan, less than 1 h. The hydrolysate defatting grade was found to depend on the degree of chitosan deacetylation. A possible mechanism of the chitosan-induced effects was suggested. The use of chitosan allows the mass fraction of enzyme protein hydrolysates to be reduced fourfold to fivefold. 相似文献
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Aiyi Liu James F. Troendle Kai F. Yu Vivian W. Yuan 《Biometrical journal. Biometrische Zeitschrift》2004,46(6):760-768
We consider estimation after a group sequential test. An estimator that is unbiased or has small bias may have substantial conditional bias (Troendle and Yu, 1999, Coburger and Wassmer, 2001). In this paper we derive the conditional maximum likelihood estimators of both the primary parameter and a secondary parameter, and investigate their properties within a conditional inference framework. The method applies to both the usual and adaptive group sequential test designs. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献