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381.
Summary Since the mixing characteristics of anaerobic reactors would appear to have an effect on their operational performance, lithium tracer studies were made on two different digester types; the upflow sludge blanket and the expanded bed reactors. The mixing characteristics of both types of reactor, defined by this technique, were found to be of the intermediate type with a bias towards good mixing. 相似文献
382.
J Massoulié S Godwin S Carson G Kato 《Biomedicine / [publiée pour l'A.A.I.C.I.G.]》1977,26(4):250-259
Muscarinic receptors have been characterized in smooth muscle and brain by the binding of reversible (e.g. atropine, quinuclidinylbenzylate) or irreversible (benzilylcholine or propylbenzilylcholine mustards) ligands. There is a close correlation between affinity constants derived from binding experiments and the affinities of muscarinic ligands for these sites obtained in pharmacological experiments on smooth muscle. Whereas atropine shows a single high affinity binding component (in subcellular preparations) several other ligands (QNB, ACh, oxotremorine) show multiple affinity binding. This indicated the existence of several types of binding sides which show selectivity toward certain cholinergic effectors. Most detergents inhibit the binding of ligands to the receptor site and therefore cannot be used to solubilize the receptor protein from the membrane. Treatment of brain subcellular membrane preparations with high salt concentrations (2M NaI) solubilize proteins which possess the muscarinic ligand binding properties observed in the membrane preparation. The affinities for muscarinic antagonists however are decreased, which suggests that a conformational change occurs in the protein upon solubilization. 相似文献
383.
Esther N. Mwangi Robin M. Newson Godwin P. Kaaya 《Experimental & applied acarology》1991,12(3-4):153-162
In experiments done over a period of 1 1/2 years using engorged femaleRhipicephalus appendiculatus tethered in a grass plot, 42% predation was observed in long grass (40–60 cm), and 36% in short grass (6–10 cm). Deaths due to environmental factors were 4.8% and 6.8% in long and short grass, respectively.Six groups of animals were confirmed to be predators of the ticks, namely: ants, spiders, rodents, birds, lizards and shrews.The implications of these results in making tick population models, and the possibility of using predators in integrated tick-control packages are discussed. 相似文献
384.