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911.
912.
Relation between total and exchangeable sodium in the body 总被引:1,自引:0,他引:1
913.
Information processing along the course of a visual interneuron. 总被引:1,自引:0,他引:1
Locust ocellar retinal cells are innervated by giant second order cells, 2 mm long, which show discrete zones of integration along their course, including a major zone in the axonal length of the neuron. The complex synaptic arrangements which exist between higher-order afferent and efferent cells and these second order cells along their course suggests that transmission takes place by the electrotonic spread of slow potentials. The size and accessibility of these visual interneurons offers a unique preparation for examining mechanisms of graded synaptic transmission. 相似文献
914.
5-Methylcytosine localised in mammalian constitutive heterochromatin 总被引:26,自引:0,他引:26
915.
Early changes of cyclic nucleotide levels in a mitogenic reaction in the rat mesentery. 总被引:2,自引:0,他引:2
By measuring simultaneously cAMP and cGMP we found a biphasic time course with regard to cGMP and the cGMP/cAMP ratio very early in a mitogenic reaction in vivo. This is a new finding. 相似文献
916.
917.
918.
Jérémie Gautheron Gilles Courtois 《Cellular and molecular life sciences : CMLS》2010,67(18):3101-3113
Ubiquitination has emerged over the years as the most sophisticated way to modify proteins to affect their fate and function.
In particular, it has been reported to be instrumental in regulating several steps of the NF-κB signalling pathway which controls
inflammation, immunity, adhesion and cell survival. Integrating ubiquitination into NF-κB activation requires the regulatory
subunit of IKK, NEMO, which not only displays affinity for polyubiquitin chains, but is also posttranslationally modified
by a complex set of reactions involving ubiquitin. Here, we examine how studies of the NEMO/ubiquitin relationship have provided
novel insights into the IKK activation process and have uncovered molecular mechanisms that should represent in the future
attractive targets for specifically modulating NF-κB function. 相似文献
919.
920.
Transthyretin (formerly called prealbumin) plays important physiological roles as a transporter of thyroxine and retinol-binding
protein. X-ray structural studies have provided information on the active conformation of the protein and the site of binding
of both ligands. Transthyretin is also one of the precursor proteins commonly found in amyloid deposits. Both wild-type and
single-amino-acid-substituted variants have been identified in amyloid deposits, the variants being more amyloidogenic. Sequencing
of the gene and the resulting production of a transgenic mouse model have resulted in progress toward solving the mechanism
of amyloid formation and detecting the variant gene in individuals at risk.
Received 23 January 2001; received after revision 4 April 2001; accepted 30 April 2001 相似文献