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In rats exposed to 400 revolutions (during 6 min and 40 sec) in rotating Noble-Collip drums essentially the same increase of the active form of hepatic glycogen phosphorylase as in animals studied 6 min and 40 sec after epinephrine (50 microgram/kg) or glucagon (100 microgram/kg), both i.v., was observed. However, in rats injured daily for 6 days, on day 7 this enzyme response was substantially blunted. 相似文献
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A one-dimensional model of a buried channel CCD is presented. The potential equations, using the depletion region approximation are solved for a range of doping levels and stored charge. In this way values of device capacitance are calculated.It is shown that for a device with uniform layer and substrate dopings, the equations have an analytic solution. These solutions take a rather complicated form, but have a simple geometrical representation. A geometrical construction, based on field plots, is given. This construction may be used in the study of more general doping profiles. 相似文献
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A. Royer N. Naulet F. Mabon M. Lees G. J. Martin 《Journal of the American Oil Chemists' Society》1999,76(3):1-9
Site-specific isotope fractionation of hydrogen was investigated, at natural abundance, by deuterium nuclear magnetic resonance
(SNIF-NMR) on nearly two hundred olive oil samples. Owing to the complexity of the 2H-NMR spectra of the mixtures of fatty acids obtained after hydrolysis of the oils, the different signals were gathered into
six clusters. Knowing the contribution to the clusters of each of the four fatty acids considered (C16:0, C18:0, C18:1, and C18:2) and the composition of the fatty acids in the mixture, it is possible to compute the site-specific isotope ratios of the
clusters from the molar fractions obtained from the 2H-NMR-spectra and from the total isotope ratio of the mixture, determined by isotope ratio mass spectrometry (IRMS). The results
are discussed in terms of geographical (country, region and elevation) and temporal (year) parameters and they are tentatively
explained on a climatic basis. 相似文献
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V Hawkins D Doll R Bumgarner T Smith C Abajian L Hood PS Nelson 《Canadian Metallurgical Quarterly》1999,27(1):204-208
Naloxone is generally considered to be a pure antagonist, but it may produce several behavioral effects, such as hyperalgesia or stimulation of respiration. We studied the effect of naloxone on gastric emptying and gastrointestinal transit in rats. Six to eight Wistar rats (200-250 g) were used for each experiment. Either saline or naloxone (0.01-10 mg/kg) was injected intraperitoneally at 0 min. At 30 min, radiolabeled saline or milk 1 mL was infused into the stomach. At 60 min, gastric emptying and gastrointestinal transit were calculated by measuring the radioactivity in the gastrointestinal tract. Naloxone significantly inhibited gastric emptying of saline (P = 0.002) and of milk (P < 0.05), but not the gastrointestinal transit of either (P > 0.05). Gastric emptying of saline showed a significant peak (P < 0.05) in the dose-response curve at 0.7 mg/kg. Therefore, naloxone significantly inhibits gastric emptying of saline and milk, but not the gastrointestinal transit of either. IMPLICATIONS: Although naloxone is generally considered to be a pure opioid receptor antagonist, it delays gastric emptying of saline or milk, as does morphine in the rat. However, it is uncertain from our results whether naloxone inhibited gastric emptying by antagonizing the effects of endogenous opioids. 相似文献