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The application of affinity capillary electrophoresis (ACE) to the study of molecular interactions is reviewed. ACE appears to be a sensitive, versatile and convenient tool to obtain reliable data on binding constants and stoichiometries of interacting systems using the Hummel-Dreyer method and variants thereof. A powerful feature is the possibility to analyze simultaneously the affinity of a large number of compounds for the same ligand, making it a promising tool for the screening of large combinatorial libraries.  相似文献   
994.
Western analysis and immunohistochemistry were used to determine the time-course and the distribution of the 27,000 mol. wt heat shock protein, Hsp27, in rat brain following systemic administration of kainic acid. No Hsp27 immunoreactivity was detected in naive control animals or in rats that failed to develop status epilepticus. Hsp27 immunoreactivity was detected as early as 12 h in the parietal cortex, piriform cortex and the hippocampus of rats that developed status epilepticus. The number of cells expressing Hsp27 and the intensity of Hsp27 immunoreactivity were increased 24 h after kainic acid administration. Hsp27 immunoreactivity was still observed seven days post-kainic acid injection. The morphology of the Hsp27-positive cells and double immunofluorescence against Hsp27 and glial fibrillary acidic protein revealed that Hsp27-positive cells were astrocytes. In addition, the distribution of Hsp27 suggested that astrocytic Hsp27 was dependent on excitation-induced metabolic stress rather than the direct effect of kainic acid on astrocytes.  相似文献   
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Over the last two-and-a-half years a committee of experts, consisting of members of the three leading German sexology associations, developed guidelines for treating and assessing transsexuals. Their purpose is to improve the care for patients with sex identity disorders and to ensure that such care is of uniform quality to avoid erroneous decisions to the disadvantage of those affected. The guidelines are set out in full.  相似文献   
997.
The substitution of the sterically hindered carbon of the potent thyroid hormone agonist, GC-1, was effected by a reaction based on the solvolysis of the benzylic hydroxyl group. The reaction was found to proceed in high yield with a variety of nucleophiles including alcohols, thiols, allyl silanes and electron-rich aromatic compounds, providing a convenient route to the synthesis of new thyroid hormone analogues.  相似文献   
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Corticotropin releasing hormone (CRH) has been localized to interneurons of the mammalian cerebral cortex, but these neurons have not been fully characterized. The present study determined the extent of co-localization of CRH with glutamate decarboxylase (GAD) and calcium-binding proteins in the infant rat neocortex using immunocytochemistry. CRH-immunoreactive (ir) neurons were classified into two major groups. The first group was larger and consisted of densely CRH-immunostained small bipolar cells, predominantly localized to layers II and III. The second group of CRH-ir cells was lightly labeled and included multipolar neurons mainly found in deep cortical layers. Co-localization studies indicated that the vast majority of CRH-ir neurons, including both bipolar and multipolar types, was co-immunolabeled for GAD-65 and GAD-67. Most multipolar, but only some bipolar, CRH-ir neurons also contained parvalbumin, while CRH-ir neurons rarely contained calbindin or calretinin. These results indicate that virtually all CRH-ir neurons in the rat cerebral cortex are GABAergic. Furthermore, since parvalbumin is expressed by cortical basket and chandelier cells, the co-localization of CRH and parvalbumin suggests that some cortical CRH-ir neurons may belong to these two cell types.  相似文献   
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