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661.
As part of continuing multidisciplinary studies on the neuropathogenesis of subacute sclerosing panencephalitis (SSPE), in situ hybridisation, immunocytochemistry and electron microscopy were used to detect measles virus nucleic acid, protein and nucleocapsids in brain perivascular infiltrates of three cases. Perivascular cuffing cells which contained measles virus nucleic acid and antigens were found in all cases. Infected cuffs occurred predominantly in areas of general parenchymal cell infection and in many of these a high proportion of the infiltrating cells were infected. Other cuffs in these areas were either uninfected or contained only a few infected cells. Occasional infected cells were also seen in cuffs in non-infected areas. In contrast, no specific immunocytochemical reactions or in situ hybridisation for measles virus was observed in brain tissue from a patient with herpes encephalitis. By electron microscopy viral nucleocapsid, consistent with measles virus, was found within the cytoplasm of plasma cells in the inflammatory cuffs in SSPE brain tissue. Possible explanations for our results are that infiltrates become infected on arrival in the CNS or alternatively, that the infected infiltrates reflect a generalised infection of the reticuloendothelial system. The frequent presence of uninfected cuffs favours the former explanation. 相似文献
662.
The authors studied the action of lithium ions on the responses of rat dorsal root ganglion neurons and frog spinal motoneurons evoked by monoamine agonists using the microelectrode technique. Lithium ions reversibly inhibit the depolarizing responses of spinal sensory neurons and motoneurons evoked by activation of muscarinic choline-, alpha 1-adreno-, and 5-hydroxytryptamine2 receptors, but enhance the hyperpolarizing neuronal responses evoked by activation of 5-hidroxytryptamine1A receptors. 相似文献
663.
Recent emphasis on producing energy from woody biomass has raised questions about the impact of a wood-energy market on the U.S. South’s wood supply chain. We surveyed wood-energy facilities, fibermills, sawmills, private landowners, and government landholders to investigate the expected impact of a vibrant wood-energy market on the southern wood supply chain. Specifically, our study was designed to document potential competition for resources, wood supply chain profitability, and landowner willingness to sell timber to energy facilities. Results indicate that wood-energy facilities and traditional mills were not competing for raw material on a large scale at the time of the study, but competition is expected over the next decade. Almost 90% of fibermills reported that traditional forest industry mills should enter the wood-energy market, but most were skeptical that the new market would improve profitability. Ninety percent of responding landowners reported a willingness to sell to energy facilities if the right price is offered and all of those who had already sold timber to an energy facility were satisfied with the experience. Only 3.5% of respondents were unwilling to sell timber to an energy company, and only one of these respondents listed timber production as a primary objective, which indicates those who would not harvest timber for energy, may be unlikely to harvest timber for other purposes also. This study suggests that the southern wood supply chain is in position to profit from a wood-energy market; however, concerns remain about the coexistence of the forest products and wood-energy industries. 相似文献
664.
Matthew Colachis Krenar Shqau Samuel Colachis IV Nicholas Annetta Amy M. Heintz 《应用聚合物科学杂志》2020,137(21):48998
A new material, classified as a soft mixed ionic–electronic conductor (MIEC), was fabricated through casting and curing of different ratios of single walled carbon nanotube (SWNTs), hyaluronic acid (HA), and acrylonitrile butadiene copolymer latex (NBR) and developed for noninvasive stimulation for electrotherapeutics. The morphology of the composite yielded high electrical conductivity and retention of elasticity. The interfacial charge transfer of the material showed that by increasing the HA loading the capacitive contribution decreased, while increasing SWNT loading decreased the interfacial resistance. The soft MIEC materials interfacial charge transfer was superior than current state-of-the art electrodes on the market. A layered configuration with high HA ratio at the skin interface and high SWNTs ratio at the stainless-steel interface was created to induce the most optimal charge transfer. These soft MIEC electrodes will be extremely helpful in electrotherapeutic applications to eliminate the need for hydrogels, which can be unsuitable due the their lack long term durability and instability. 相似文献
665.