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971.
Plasma choline concentrations were measured in humans, rats, and rabbits within the first few hours of life, before any food was ingested. Neonatal animals and humans had markedly elevated plasma choline levels compared to adult animals or humans. Possible mechanisms responsible for this elevation are discussed and possible consequences for brain function, lung function, and growth are presented. 相似文献
972.
973.
A. V. Andriyash D. A. Vikhlyaev D. A. Dmitrov A. L. Zapysov A. G. Kakshin I. A. Kapustin E. A. Loboda V. A. Lykov A. V. Potapov V. A. Pronin V. N. Sanzhin V. N. Saprykin A. A. Ugodenko O. V. Chefonov M. N. Chizhkov 《Plasma Physics Reports》2006,32(2):135-137
Results are presented from experimental investigations of the angular distributions and energy spectra of fast ions produced in deuterium polyethylene targets under irradiation by picosecond laser pulses with intensities of up to 2 × 1018 W/cm2 in the SOKOL-P facility. The parameters of ion fluxes were measured by time-of-flight spectrometers based on semiconductor detectors. 相似文献
974.
I M Chaiken 《The Journal of biological chemistry》1971,246(9):2948-2952
975.
976.
977.
978.
979.
The quality of milk products is threatened by the formation of biofilms of thermophilicstreptococci on the internal surfaces of plate heat exchangers used in milk processing. Althoughattachment to stainless steel surfaces is one of the first stages in the development of a biofilm, themechanisms involved in attachment have not been reported. The cell surface properties of 12strains of thermophilic streptococci were examined to determine their importance in attachment tostainless steel surfaces. Hydrophobicity, extracellular polysaccharide production and cell surfacecharge varied between the different strains but could not be related to numbers attaching. Treatingthe cells with sodium metaperiodate, lysozyme or trichloroacetic acid to disrupt cell surfacepolysaccharide had no effect on attachment. Treatment with trypsin or sodium dodecyl sulphate toremove cell surface proteins resulted in a 100-fold reduction in the number of bacteria attaching.This result suggests that the surface proteins of the thermophilic streptococci are important intheir attachment to stainless steel. 相似文献
980.
D Mitchell H P Laburn K E Cooper R F Hellon W I Cranston Y Townsend 《The Yale journal of biology and medicine》1986,59(2):159-168
We have reviewed the evidence in favor of a prostaglandin mediator of the thermal responses in fever and found that PGE injected into the hypothalamus does not always cause fever, that cerebrospinal fluid concentrations of PGE are not reliable reflections of hypothalamic events, and that antipyretic drugs may act in ways other than inhibiting PGE synthesis. Fever is not blocked by prostaglandin antagonists, nor by ablation of PGE-sensitive areas of the brain. There is poor correlation between the effects of pyrogens and of PGE on cerebral neurons. There is evidence that at least one prostanoid other than prostaglandin is a mediator of fever, but the prostanoid has not been identified yet. We conclude that PGE may contribute to the neural responses in fever but is not essential. 相似文献