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961.
Mycobacterium leprae, the causative agent of leprosy, specifically invades and destroys the peripheral nerve, which results in the main clinical manifestation of the disease. Little is known about the bacteria—nerve protein interaction. We show in the present work that M leprae binds to a 25 kDa glycoprotein from human peripheral nerve. This protein is phosphorylatable and it binds to lectins which have alpha-mannose specificity. This M leprae-protein interaction could be of importance in the pathogenesis of leprosy.  相似文献   
962.
Dysregulation of the brain-specific tau protein kinase II (TPK II)/cdk5 is reported to play an important role in the pathogenesis of Alzheimer's disease. We report here a quantitative scintillation proximity assay (SPA), which is suitable for determining TPK II/cdk5 activity and its inhibition. It depends upon the phosphorylation of a synthetic histone-based peptide substrate (PKTPKKAKKL), which has been biotinylated at its C-terminus. When this biotinylated peptide is incubated with [γ-33P] ATP and TPK II/cdk5 under defined assay conditions, product formation is linear with respect to time and enzyme concentration. The production of [33P] phosphorylated peptide is inhibited in the presence of a known TPK II/cdk5 inhibitor but is unaffected in the presence of 1% DMSO. A signal-to-noise ratio of 16:1 was obtained in a 60-min assay with an intra-assay variability of <10% in the 96-well microtiter format. The TPK II/cdk5 SPA is very robust, sensitive and simple to perform.  相似文献   
963.
We report the synthesis and biological evaluation of a two-chain, disulfide-linked, insulin-like compound consisting of the B-chain of bovine insulin and an A-chain corresponding to the A- and D- domains of human insulin-like growth factor-I (IGF-I) in which the A-domain amino-acid residues -Phe49-Arg50-Ser51- found in IGF-I have been replaced by -Ala-Gly-Val-, the homologous region of sheep insulin. The compound is indistinguishable from a previously reported compound whose A-chain corresponds to the A- and D-domains of IGF-I without the substitution, in assays for insulin-like activity as well as in assays for growth-promoting activity. We conclude that these A-domain residues do not contribute significantly to the interaction of IGF-I with either insulin or IGF-I receptors.A preliminary discussion of this work was presented (P.G.K.) to the 19th European Peptide Symposium, Porto Carras, Greece, 1986.  相似文献   
964.
Spike trains from neurons are often used to make inferences about the underlying processes that generate the spikes. Random walks or diffusions are commonly used to model these processes; in such models, a spike corresponds to the first passage of the diffusion to a boundary, or firing threshold. An important first step in such a study is to fit families of densities to the trains' interspike interval histograms; the estimated parameters, and the families' goodness of fit can then provide information about the process leading to the spikes. In this paper, we propose the generalized inverse Gaussian family because its members arise as first passage time distributions of certain diffusions to a constant boundary. We provide some theoretical support for the use of these diffusions in neural firing models. We compare this family with the lognormal family, using spike trains from retinal ganglion cells of goldfish, and simulations from an integrate-and-fire and a dynamical model for generating spikes. We show that the generalized inverse Gaussian family is closer to the true model in all these cases. Received: 16 September 1996 / Accepted in revised form: 2 July 1997  相似文献   
965.
The ninth edition of the congress of the European Association of Echocardiography (EAE) (former working group of Echocardiography) held in Florence has just finished with a great success of participant attendance (2.842) and abstract submissions. Hot topics at EuroEcho 9 were: 1-live 3-dimensional echocardiography and surgical decision making; in pediatric cardiology; in resynchronization therapy 2- stress echocardiography beyond wall motion: from valve diseases to contractility to coronary flow reserve to diastolic function; 3- pulmonary cardiogenic interstitial thickening recognized by ultrasonic lung comets; 4- the "proven clinical inefficacy" of the many technologies sold as breakthrough: color kinesis, tissue characterization, strain rate, tissue Doppler, applied to stress echocardiography.  相似文献   
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