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41.
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Eoin E. Kelly Conor P. Horgan Mary W. McCaffrey Paul Young 《Cellular and molecular life sciences : CMLS》2011,68(2):185-194
Long-term potentiation (LTP) defines persistent increases in neurotransmission strength at synapses that are triggered by
specific patterns of neuronal activity. LTP, the most widely accepted molecular model for learning, is best characterised
at glutamatergic synapses on dendritic spines. In this context, LTP involves increases in dendritic spine size and the insertion
of glutamate receptors into the post-synaptic spine membrane, which together boost post-synaptic responsiveness to neurotransmitters.
In dendrites, the material required for LTP is sourced from an organelle termed the endosomal-recycling compartment (ERC),
which is localised to the base of dendritic spines. When LTP is induced, material derived from the recycling compartment,
which contains α-amino-3-hydroxy-5-methyl-4-isoxazole propionate-type glutamate receptors (AMPARs), is mobilised into dendritic
spines feeding the increased need for receptors and membrane at the spine neck and head. In this review, we discuss the importance
of endosomal-recycling and the role of key proteins which control these processes in the context of LTP. 相似文献
43.
J. Young 《Systemic Practice and Action Research》2010,23(1):101-113
Representation assumes that those who govern have knowledge of those for whom they govern. It is easy to presume knowledge of the “other”, but as we know this can be based in prejudice, cultural difference, or simply misinformation or simplification. Usually our explorations of this process have focused on populations identified as disadvantaged, disempowered or somehow “non-privileged”. However, the research process outlined here has revealed previously unexplored diversity within a population commonly described as privileged suggesting that good governance requires alertness to presuming to know both the unprivileged and the privileged. The research approach outlined in this paper has used a blend of historical reappraisal and qualitative techniques focusing on a population who have been conceptualized as doubly privileged. This population focus is that of older British; post World War II male migrants in South Australia. These people have been conceptualized as privileged because they are male, and they were part of the preferred ethnic group that Australian politicians and policy makers favoured post WW2. However, review of the historical data and qualitative interviews with some of these men show that the accepted narrative of a homogenous pre-WW2 British origin population is over simplistic. The historical research suggests that the presumption that post WW2 British migrant men were coming into an homogenous, privileging environment in migrating to SA is both ahistorical and crude. Furthermore the belief that post WW2 British migrant men were ethnically homogenous is undermined by the qualitative research, that reveals that their presumed homogeneity is much more fluid and nuanced than dominant conceptualisations have allowed. The impact of core ethnicities that continue to exist and compete in Britain, the social class focus and economic commodification of migrants in the machinations of powerful players in the state of South Australia all confound homogenizing, simplistic knowing of British migrant men in this state. Generically these findings caution social researchers with regard to presuming to know so called “privileged” populations as well as presumed non-privileged groups. 相似文献
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D. A. B. Young 《Cellular and molecular life sciences : CMLS》1976,32(11):1389-1390
Summary Suspensions of isolated cells from rat heart were prepared and the data for viability and yield are given. Glucose uptake by the cells was mediated by a carrier system.The technical assistance of Mr.E. T. Potter, Mr.K. D. Patel and Mr.M. Griffin is gratefully acknowledged. 相似文献
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Summary Treatment of post-feeding larvae of the cabbage maggotDelia radicum with methoprene did not affect the capacity of the insect to pupate, but suppressed eclosion to the adult stage. The concentration of hemolymph trehalose was significantly decreased by methoprene treatment, although hemolymph protein and amino nitrogen levels were unaffected.19 December 1986The authors are grateful to D. C. Read of the Research Centre, Agriculture Canada, Charlottetown, P.E.I., Canada for supplying eggs ofD. radicum for the stock colony. TheD. radicum colony was maintained at the Agriculture Canada Research Station, St. John's West, Newfoundland, Canada. The sample of methoprene was donated by Zoecon Corp., Palo Alto, California, U.S.A. This research was supported by a grant from the Natural Sciences and Engineering Research Council of Canada (Operating grant A6679). 相似文献
49.
Transposon-dependent mutant phenotypes at the Notch locus of Drosophila 总被引:10,自引:0,他引:10
Many mutations at complex genetic loci in the fruitfly Drosophila melanogaster are associated with insertions of transposable elements. At the Notch locus, members of one class of insertion-associated mutations, termed glossy-like, produce a recessive viable, smooth-eye phenotype with mottled pigmentation. Members of a second class, facet, produce a recessive viable, rough-eye phenotype with homogeneous pigmentation. Both classes of mutations fail to complement Notch lethal mutations, so they behave as Notch alleles. Here we report that each glossy-like mutation is associated with an insertion of the same transposable element (flea). Each flea insertion occurs in the same orientation, but at different locations within intervening sequences of the Notch locus. In contrast, each facet mutation is associated with insertion of a unique, non-flea, transposable element. Insertions producing a facet phenotype and insertions causing a glossy-like phenotype can break Notch intervening sequences at precisely the same location. This suggests that the type of insertion element rather than its position within an affected gene is the primary determinant of the phenotype observed. 相似文献
50.
Zusammenfassung Mit Hilfe der «stopped-flow»-Mikroperfusionstechnik wurden am Samenkanälchen Elektrolyttransportprozesse untersucht. Es wurde gefunden, dass die Kanälchen ein kaliumreiches Primärsekret bilden. Dieses unterscheidet sich in seiner Zusammensetzung von dem Sekret, das man gewöhnlich unter ungestörten Fliessbedingungen findet.
This project was supported by the Rural Bank of Australia. One of us (R.D.H.) thanks the National Health and Medical Research Council of Australia for the award of a B.Sc. (med.) studentship for 1970. 相似文献
This project was supported by the Rural Bank of Australia. One of us (R.D.H.) thanks the National Health and Medical Research Council of Australia for the award of a B.Sc. (med.) studentship for 1970. 相似文献