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71.
Foley AG Hartz BP Gallagher HC Rønn LC Berezin V Bock E Regan CM 《Journal of neurochemistry》2000,74(6):2607-2613
The neural cell adhesion molecule (NCAM) mediates cell adhesion and signal transduction through trans-homophilic- and/or cis-heterophilic-binding mechanisms. Intraventricular infusions of anti-NCAM have revealed a functional requirement of NCAM for the consolidation of memory in rats and chicks in a specific interval 6-8 h after training. We have now extended these studies to a synthetic peptide ligand of NCAM (C3) with an affinity for the IgI domain and the capability of inhibiting NCAM-mediated neurite outgrowth in vitro. Intraventricular administration of a single 5 microg bolus of C3 strongly inhibited recall of a passive avoidance response in adult rats, when given during training or in the 6-8-h posttraining period. The effect of C3 on memory consolidation was similar to that obtained with anti-NCAM as the amnesia was not observed until the 48-h recall time. The unique amnesic action of C3 during training could be related to disrupted NCAM internalization following training. In the 3-4-h posttraining period NCAM 180, the synapse-associated isoform, was down-regulated in the hippocampal dentate gyrus. This effect was mediated by ubiquitination and was prevented by C3 administration during training. These findings indicate NCAM to be involved in both the acquisition and consolidation of a passive avoidance response in the rat. Moreover, the study provides the first in vivo evidence for NCAM internalization in learning and identifies a synthetic NCAM ligand capable of modulating memory processes in vivo. 相似文献
72.
Grip strength changes over 27yr in Japanese-American men 总被引:3,自引:0,他引:3
Rantanen T.; Masaki K.; Foley D.; Izmirlian G.; White L.; Guralnik J. M. 《Journal of applied physiology》1998,85(6):2047-2053
The aim of thisstudy was to describe changes in grip strength over a follow-up periodof ~27 yr and to study the associations of rate of strength declinewith weight change and chronic conditions. The data are from theHonolulu Heart Program, a prospective population-based studyestablished in 1965. Participants at exam1 were 8,006 men (ages 45-68 yr) who were ofJapanese ancestry and living in Hawaii. At follow-up, 3,741 men (agerange, 71-96 yr) participated. Those who died before the follow-upshowed significantly lower grip-strength values at baseline than didthe survivors. The average annualized strength change among thesurvivors was 1.0%. Steeper decline (>1.5%/yr) wasassociated with older age at baseline, greater weight decrease, andchronic conditions such as stroke, diabetes, arthritis, coronary heartdisease, and chronic obstructive pulmonary disease. The risk factorsfor having very low hand-grip strength at follow-up, here termedgrip-strength disability (21 kg, the lowest 10th percentile), werelargely same as those for steep strength decline. However, theage-adjusted correlation between baseline and follow-up strength wasstrong (r = 0.557, P < 0.001); i.e., those who showedgreater grip strength at baseline were also likely to do so 27 yrlater. Consequently, those in the lowest grip-strength tertile atbaseline had about eight times greater risk of grip-strength disabilitythan those in the highest tertile because of their lower reserve ofstrength. In old age, maintenance of optimal body mass may help preventsteep strength decrease and poor absolute strength. 相似文献
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74.
Chemical differentiation along metaphase chromosomes 总被引:32,自引:0,他引:32
T Caspersson S Farber G E Foley J Kudynowski E J Modest E Simonsson U Wagh L Zech 《Experimental cell research》1968,49(1):219-222
75.
Induction of delta-Aminolevulinic Acid Synthase Activity and Inhibition of Heme Synthesis in Euglena gracilis by N-Methyl Mesoporphyrin IX 下载免费PDF全文
N-Methyl mesoporphyrin IX, an inhibitor of heme synthesis, increases extractable δ-aminolevulinic acid (ALA) synthase activity when administered to growing cultures of Euglena gracilis Klebs strain Z Pringsheim in micromolar concentrations. Wild-type light-grown green cells and white aplastidic cells exhibited 2.8-fold and 1.8-fold increases, respectively, in ALA synthase activity within five to six hours after incubation with 4 × 10−6 molar N-methyl mesoporphyrin IX. Protoheme levels were decreased and 59Fe incorporation into heme was inhibited by N-methyl mesoporphyrin IX, indicating that, as in animal cells, N-methyl mesoporphyrin IX acts specifically to block iron insertion into protoporphyrin IX. Chlorophyll synthesis in wild-type cells was not affected within the first 6 hours after administration of N-methyl mesoporphyrin IX. 相似文献
76.
Douglas E. Foley 《Anthropology & education quarterly》1999,30(4):488-490
Ethnic Identity and Power. Cultural Contexts of Political Action in School and Society. Yali Zou and Enrique T. Trueba. eds. Albany: State University of New York Press, 1998. 452 pp. 相似文献
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79.
Melanie J. Edwards Ian R. Wallis William J. Foley 《Journal of comparative physiology. B, Biochemical, systemic, and environmental physiology》2010,180(2):247-257
We fed common brushtail possums artificial diets containing a buffer and the plant secondary metabolite (PSM), orcinol, to
test the hypothesis that organic acids, common products of PSM metabolism, limit feeding by common brushtail possums (Trichosurus vulpecula). We introduced several diets containing orcinol and a buffer (urinary alkalising agent) over a course of three experiments.
A diet containing 2% orcinol (wet matter) caused possums to reduce their food intake immediately, but feeding returned to
normal 1–2 days later. Even though possums excreted strongly acidic urine (pH 5.1) and had perturbed nitrogen metabolism,
they maintained their food intake and body mass until the experiment terminated 9 days after the introduction of orcinol.
Possums ate 52% less when the basal diet contained 4% orcinol. As expected, the acid loads caused a change in the composition
of urinary nitrogen with possums excreting more ammonium than urea and a large amount of unidentified nitrogenous material.
Supplementing the diet containing orcinol with buffer neutralised the metabolic acid load and partly restored normal nitrogen
metabolism, but did not restore feeding. Also, animals eating orcinol excreted normal amounts of 3-methylhistidine, indicating
no increase in muscle protein catabolism. This suggests that a limitation to the rate of detoxification or toxicosis, rather
than acid loads, limits the ingestion of acid-inducing PSMs. 相似文献
80.
Anne Marie McLaughlin Muhammad Farooq Maria B Donnelly Kieran Foley 《BMC anesthesiology》2010,10(1):1-5