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Brian A. Bayless Thomas H. Giddings Jr. Mark Winey Chad G. Pearson 《Molecular biology of the cell》2012,23(24):4820-4832
Basal bodies nucleate, anchor, and organize cilia. As the anchor for motile cilia, basal bodies must be resistant to the forces directed toward the cell as a consequence of ciliary beating. The molecules and generalized mechanisms that contribute to the maintenance of basal bodies remain to be discovered. Bld10/Cep135 is a basal body outer cartwheel domain protein that has established roles in the assembly of nascent basal bodies. We find that Bld10 protein first incorporates stably at basal bodies early during new assembly. Bld10 protein continues to accumulate at basal bodies after assembly, and we hypothesize that the full complement of Bld10 is required to stabilize basal bodies. We identify a novel mechanism for Bld10/Cep135 in basal body maintenance so that basal bodies can withstand the forces produced by motile cilia. Bld10 stabilizes basal bodies by promoting the stability of the A- and C-tubules of the basal body triplet microtubules and by properly positioning the triplet microtubule blades. The forces generated by ciliary beating promote basal body disassembly in bld10Δ cells. Thus Bld10/Cep135 acts to maintain the structural integrity of basal bodies against the forces of ciliary beating in addition to its separable role in basal body assembly. 相似文献
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Ralph G. Pearson 《Inorganica chimica acta》1998,270(1-2):252-260
A simple bonding model previously used to calculate cohesive energies is used to calculate electronic properties of simple solids. The model assumes that AB compounds of CN6 or 8 are completely ionic and that CN4 compounds, and metals, are completely covalent. It is then possible to calculate the electronic chemical potential, the work function and the average energy gap between filled and empty bands in insulators, semiconductors and conductors. 相似文献
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A procedure based on that of Van Slyke and LoMonte (Microchem. J.14, 608–626, 1969) is described for the mass spectrometric analysis of 15N in nitrate extracted from plant tissue. The extract is evaporated to dryness in a disposable borosilicate test tube, which forms the basal part of a reaction flask. After evacuation of the flask, nitrate is reduced to nitric oxide by sonication with mercury in 18 n H2SO4. The atom percentage 15N is calculated from the relative intensities of the 14NO and 15NO peaks of the mass spectrum. The method is unaffected by reduced nitrogen compounds which are present in plant tissue extracts. 相似文献
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Sixteen patients with an early dense hemiplegia due to cerebrovascular accidents were shown to have a greater degree of hypoxia than 16 matched control patients. The patients with hemiplegia had a reflex compensatory fall in arterial carbon dioxide tensions (PaCO2) with possible reduction in cerebral blood flow. Oxygen treatment led to an increase in PaCO2 in the patients with hemiplegia, but the increase in oxygen tensions in these patients was significantly less than that in the control group, suggesting increased pulmonary shunting as the cause for the hypoxia. Oxygen treatment may improve cerebral blood flow and oxygenation and have a useful role in the early management of patients with a dense hemiplegia. 相似文献