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71.
KN Furuya PR Durie EA Roberts SJ Soldin Z Verjee L Yung-Jato E Giesbrecht L Ellis 《Canadian Metallurgical Quarterly》1995,28(5):531-540
N-Acetyl aspartate (NAA) is the second most abundant amino acid in the human brain. NAA is synthesized by L-aspartate N-acetyl transferase or by cleavage from N-acetyl aspartyl glutamate by N-acylated alpha-linked L-amino dipeptidase (NAALADase); and it is catabolized to acetate and aspartate by N-acetyl aspartate amino hydrolase (amino acylase II). NAA is localized primarily to neurons, where it is concentrated in the cytosol. Although NAA is devoid of neurophysiological effects, it serves as an acetyl donor, an initiator of protein synthesis or a carbon transfer source across the mitochondrial membrane. The concentration of NAA in human brain increases 3-fold between midgestation and adulthood. In Canavan's Disease, an autosomal recessive disorder due to a null mutation in amino acylase II, NAA levels in brain are markedly increased and disrupt myelination. NAA levels have been found to be reduced in neurodegenerative disorders, including Alzheimer's Disease and Huntington's Disease. Since endogenous NAA can be readily detected in human brain by magnetic resonance spectroscopy, it is increasingly being exploited as a marker for functional and structural integrity of neurons in an expanding number of disorders. 相似文献
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D. B. Carlisle Peggy E. Ellis Daphne J. Osborne 《Journal of the science of food and agriculture》1969,20(7):391-393
Gibberellic acid is a necessary dietary constituent for normal fast maturation in the desert locust. Diets short of gibberellins, such as senescent vegetation, produce a state of adult diapause. The synthetic plant growth retardant (2-chloroethyl)-trimethylammonium chloride (CCC), either injected into locusts or fed to them as a separate dietary constituent, inhibits meiosis and so retards or prevents sexual maturation. Once this stage of gametogenesis has passed (late in nymphal life) CCC appears to have no further effect, but a single injection just before the onset of meiosis will sterilise locusts completely. Cotton stainers provided with a solution of CCC in their drinking water during the same period of larval life show impaired reproductive function and produce deformed offspring. CCC acts directly upon the insects, quite apart from any secondary effect produced by the altered physiology of the food plant. 相似文献
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Replies to P. W. Sharkey's (see record 1982-26956-001) critique of some of the theories of rational emotive psychology (REP) and their relationship to rational emotive therapy. Responding to Sharkey's objections, it is concluded that (1) REP remains well within the field of science although, like science, it rests on some evaluative assumptions and (2) REP does not attack all religious hypotheses but only those that are absolute and that sabotage human health and happiness. (15 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
77.
A 40 cm3 recycling vapour liquid equilibrium still is described with direct injection of the vapour into the carrier stream of a chromatography analytical unit. Results for testing the accuracy of the equilibrium still are presented for the miscible systems hexane—heptane, ethanol—benzene and for the partially immiscible condensate systems perfluoromethylcyclohexane-1 heptane and perfluoromethylcyclohexane-n heptane. 相似文献
78.
Pfitzer John T.; Ellis Newton C.; Johnston Waymon L. 《Canadian Metallurgical Quarterly》1972,56(3):278
Examined the feasibility of applying the static strength and endurance relationships suggested in 1960 by W. Rohmert to a simple manual task. Results indicate that there was a relationship between grip strength expenditure and impairments in task performance similar in respect to the static strength and endurance relationships suggested. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
79.
D. M. Ellis S. J. C. Irvine 《Journal of Materials Science: Materials in Electronics》2004,15(6):369-372
Thin films of cadmium oxide have been deposited onto alumino–silicate glass substrates by atmospheric pressure metal organic chemical vapor deposition using DMCd and n-butanol, a novel oxygen source. Studies were conducted to evaluate how different conditions such as temperature and precursor concentration influenced the film growth. Film characterization showed that at an optimum temperature range of 270–290 °C, CdO exhibits low spreading resistance of 17.1 per square, for a 400 nm film, compared with 10 per square for 1.1 m indium tin oxide film, and high transmittance, between 600 and 900 nm, up to 90% with a band gap of 2.4 eV. Within this optimum temperature range, the grain size and surface roughness are shown to be a minimum. 相似文献
80.
Rayne S Ikonomou MG Ross PS Ellis GM Barrett-Lennard LG 《Environmental science & technology》2004,38(16):4293-4299
Polybrominated diphenyl ethers (PBDEs), polybrominated biphenyls (PBBs), and polychlorinated naphthalenes (PCNs) were quantified in blubber biopsy samples collected from free-ranging male and female killer whales (Orcinus orca) belonging to three distinct communities (southern residents, northern residents, and transients) from the northeastern Pacific Ocean. High concentrations of sigmaPBDE were observed in male southern residents (942+/-582 ng/g Iw), male and female transients (1015+/-605 and 885+/-706 ng/g Iw, respectively), and male and female northern residents (203+/-116 and 415+/-676 ng/g Iw, respectively). Because of large variation within sample groups, sigmaPBDE levels generally did not differ statistically with the exception of male northern residents, which had lower sigmaPBDE concentrations than male southern residents, male transients, and female transients, perhaps reflecting the consumption of less contaminated prey items. Male transient killer whales, which consume high trophic level prey including other cetaceans and occasionally spend time near populated areas, had sigmaPBDE concentrations approximately equal to southern residents. No significant age-related relationships were observed for sigmaPBDE concentrations. sigmaPBDE concentrations were approximately 1-3 orders of magnitude greater than those of sigmaPBB (3.0-31 ng/g Iw) and sigmaPCN (20-167 ng/g Iw) measured in a subset of samples, suggesting that PBDEs may represent a contaminant class of concern in these marine mammals. 相似文献