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81.
82.
Neath Karly N.; Limebeer Cheryl L.; Reilly Steve; Parker Linda A. 《Canadian Metallurgical Quarterly》2010,124(3):398
Recent evidence suggests that liking and wanting of food rewards can be experimentally dissociated (e.g., Berridge, 1996); this dissociation extends to attenuated neophobia in the present study. Rats tend to eat less of a novel food than a familiar food, a phenomenon called neophobia. The present experiments evaluated whether attenuation of neophobia by prior exposure reflects enhanced liking of the flavor using the Taste Reactivity (TR) test. In Experiment 1, rats given five 10-s TR trials with water or various concentrations of saccharin solution (0.1%, 0.2%, 0.5%) did not show a change in the number of hedonic reactions displayed across trials. However, in a subsequent consumption test from a bottle containing 0.25% saccharin solution, rats with no prior saccharin exposure (group water) consumed less than rats with prior saccharin exposure; that is they displayed neophobia. In Experiment 2, whether rats received five 10-s TR trials with water or 0.5% saccharin solution, they did not display a difference in hedonic reactions to 0.25% saccharin solution in two 5-min TR test trials. These results suggest that the attenuation of neophobia is evidenced as an increase in the tendency to approach a bottle containing the flavored solution (wanting), but not as an enhanced liking of that solution. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
83.
在回顾中国黄金工业发展现状的基础上,针对黄金老矿山所面临的资源瓶颈问题,提出以科学发展观为指导,通过技术创新,积极寻求尾矿资源、难处理金矿资源和浅层地热资源开发的新办法和新途径,以拓展黄金老矿山的生存空间。 相似文献
84.
Hernandez Giovanni; Hamdani Selma; Rajabi Heshmat; Conover Kent; Stewart Jane; Arvanitogiannis Andreas; Shizgal Peter 《Canadian Metallurgical Quarterly》2006,120(4):888
Extracellular dopamine levels were measured in the rat nucleus accumbens by means of in vivo microdialysis. Delivery of rewarding medial forebrain bundle stimulation at a low rate (5 trains/min) produced a sustained elevation of dopamine levels, regardless of whether train onset was predictable. When the rate of train delivery was increased to 40 trains/min, dopamine levels rose rapidly during the first 40 min but then declined toward the baseline range. The rewarding impact of the stimulation was reduced following prior delivery of stimulation at the high, but not the low, rate. These results support the idea that dopamine tone plays an enabling role in brain stimulation reward and is elevated similarly by predictable and unpredictable stimulation. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
85.
Roman Christopher; Nebieridze Nino; Sastre Aristides; Reilly Steve 《Canadian Metallurgical Quarterly》2006,120(6):1257
The effects of permanent forebrain lesions on conditioned taste aversions (CTAs) and conditioned odor aversions (COAs) were examined in 3 experiments. In Experiment 1, lesions of the bed nucleus of the stria terminalis had no influence on CTA or COA acquisition. Although lesions of the lateral hypothalamus induced severe hypodipsia in Experiment 2, they did not prevent the acquisition of CTAs or COAs. Finally, in Experiment 3, lesions of the insular cortex retarded CTA acquisition but had no influence on COA acquisition. The implications of these findings are discussed with regard to the forebrain influence on parabrachial nucleus function during CTA acquisition. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
86.
Armstrong Donkoh Paul J Moughan Patrick C H Morel 《Journal of the science of food and agriculture》1995,67(3):359-366
The aim was to compare a recently developed peptide alimentation method and the protein-free and regression methods for determining endogenous ileal nitrogen (N) and amino acid excretion in the rat, and to apply the endogenous loss estimates to determine the true ileal digestibility of a meat and bone meal (MBM). Preliminary investigations determined the effect of the time of sampling of digesta after a meal (slaughter method) for rats given a protein-free or an enzymically hydrolysed casein (EHC) based diet, on ileal digesta and endogenous N excretion. There was a significant (P < 0.05) effect of the time of sampling on the amount of digesta collected and the endogenous N excretion for both the EHC and protein-free fed rats. The amount of digesta collected from the terminal 20 cm of ileum and the endogenous N excretion for both the EHC and protein-free fed rats were greatest and least variable at 3 h post-feeding. In the main study, endogenous ileal amino acid excretions were determined in the growing rat fed an EHC-based diet (n = 6) and with subsequent treatment of the digesta using ultrafiltration or in six rats given a protein-free diet or by extrapolation from data for 30 animals given five diets which contained graded levels of MBM as the sole protein source. For the EHC treatment, the ileal digesta precipitate plus retentate was used to determine the endogenous flows. The ultrafiltration step excludes unabsorbed dietary amino acids from the measure of endogenous loss. Chromic oxide was the reference marker in all diets. The endogenous N flows determined by the protein-free and regression methods were similar but both significantly (P < 0.01) lower than those for rats fed the EHC-based diet. The mean endogenous ileal N flows determined by the peptide alimentation method, the protein-free and regression approaches were 1866, 1103 and 1019 μg g?1 freeze dry matter intake, respectively. The endogenous amino acid flows at the terminal ileum were lower when determined using the traditional protein-free or regression methods. The true ileal digestibility coefficients for MBM were considerably higher based on the EHC versus protein-free endogenous flows. 相似文献
87.
Reports an error in "Alpha-adrenergic receptors in hypothalamus for the suppression of feeding behavior by satiety" by D. L. Margules (Journal of Comparative & Physiological Psychology, 1970[Oct], Vol 73[1], 1-12; see record 1971-03588-001). On page 3, paragraph 1 of the Method section, the angle of implantation of cannulas was 6° from the perpendicular; in paragraph 2 of the Method section, the following sentence was omitted: All rats were maintained on a reversed dark-light cycle (lights off at 0800 hr. and on at 2000 hr. EST) and were drugged in the dark. On page 10, paragraph 6, line 10 of the Discussion section, "abolishes" should read "enhances." In "Precocious mating in male rats following treatment with androgen or estrogen" by Michael J. Baum (Journal of Comparative & Physiological Psychology, 1972[Mar], Vol. 78[3], 356-367; see record 1972-22393-001), on page 367 the date of receipt should read August 24, 1970. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
88.
89.
Human growth hormone (hGH) and prolactin (hPRL) have a low sequence homology, but both bind and activate hPRL receptors. hGH also binds hGH receptors. hGH has 22 and 20 kDa forms; residues 32-46 have been deleted by alternative RNA splicing to create the smaller form. hGH requires F44 for activity through the hPRL receptor, but not for activity through the hGH receptor. The deletion of F44 from hGH has the same effect as removal of residues 32-46 (approximately 200-fold loss in activity), indicating the importance of F44 in hGH when activating the hPRL receptor. In contrast, when the homologous F50 is deleted from hPRL little or no activity is lost, indicating that this highly conserved phenylalanine is not required for the action of hPRL. Deletion of residues 41-52 (a non-conserved sequence homologous to residues 32-46 of hGH) reduced the activity of hPRL by >14 000-fold. This region is essential for the biological activity of hPRL. As these two proteins have evolved from a common ancestor, they have retained the requirement for this region but need different structural elements to activate hPRL receptors. Such diversity represents an opportunity to fine-tune hormone activity. 相似文献
90.
介绍了矿化垃圾作为稳定化垃圾的概念以及国内外的开采现状,从作为填埋场覆盖材料、土地利用、处理废水、处理废气以及建筑材料等方面概述了矿化垃圾综合利用的研究现状,并结合研究现状提出了展望。 相似文献