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BIANCA ZANI GIULIO COSSU SERGIO ADAMO MARIO MOLINARO 《Differentiation; research in biological diversity》1978,10(1-3):95-100
In primary culture of chick embryo muscle cells myosin synthesis is detected in mononucleated cells and increases at the onset of fusion with a maximal increment of 20-fold per plate in differentiated myotube. The possibility that the myosin synthetized by duplicating myoblast could be different from that present in post-mitotic myoblast and myotube was evaluated by investigating the regulation of its synthesis and the turnover of the molecule. Following Actinomycin D treatment (0.05 μg/ml, 8 h), myosin synthesis is partially affected (about 50% inhibition) in pre-fusion myoblast while the synthesis is more sensitive to the drug at the onset of fusion (80% inhibition).
With the progress of the differentiative stage the half-life of the molecule increases from 30 h in duplicating myoblasts to 200 h in fibers. The half-life of myosin synthetized by duplicating myoblasts in the explanted embryonic muscle, is 12 h.
These data show different features of myosin heavy chains related to specific stages of differentiation and suggest the possibility that modulative changes of the molecule could induce its functional maturation during myogenesis. 相似文献
With the progress of the differentiative stage the half-life of the molecule increases from 30 h in duplicating myoblasts to 200 h in fibers. The half-life of myosin synthetized by duplicating myoblasts in the explanted embryonic muscle, is 12 h.
These data show different features of myosin heavy chains related to specific stages of differentiation and suggest the possibility that modulative changes of the molecule could induce its functional maturation during myogenesis. 相似文献
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Avian life-history studies are often conducted on populations nesting in nestboxes. However, the type of nestbox used is a potentially confounding variable, as each model shows specific characteristics. In recent decades, a new commercial model of artificial nestbox made of woodcrete, a mixture of sawdust and additives, has become popular owing to its better protection against predators compared with the classic wooden design. We assess the effect of nestbox type on the breeding ecology of Tree Sparrows Passer montanus , focusing on their thermal properties, an influential factor in nestbox selection. Occupancy rates and reproductive parameters of Tree Sparrows were compared between birds breeding in woodcrete and wooden nestboxes over 5 years. Woodcrete nestboxes had a higher occupancy rate and birds breeding in them had earlier clutches, a shorter incubation period and more reproductive attempts per season than birds nesting in wooden boxes. Clutch size and nestling condition did not differ between nestbox types, but reproductive success was higher in woodcrete nestboxes. The higher temperature in woodcrete nestboxes (1.5 °C higher on average) might explain these differences. Such differences may bias results obtained in comparative studies where more than one nestbox type is used. 相似文献
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Morphological and pollen differentiation in Solanum cardiophyllum ssp. cardiophyllum and S. cardiophyllum ssp. ehrenbergii 总被引:1,自引:0,他引:1
MARIO LUNA-CAVAZOS EDMUNDO GARCÍA-MOYA 《Botanical journal of the Linnean Society. Linnean Society of London》2002,140(4):415-426
A multivariate analysis to differentiate morphologically the populations of wild potatoes Solanum cardiophyllum ssp. cardiophyllum and S. cardiophyllum ssp. ehrenbergii was carried out. An analysis of the morphology and the viability of pollen of these potato populations was also made. The results of the morphometric analysis indicate that both subspecies are phenetically different. The pollen grain shape and size in ssp. cardiophyllum are different in northern and southern populations. Pollen diameter is significantly different between subspecies. Based on these results we propose that these taxa should be considered as two separate species. © 2002 The Linnean Society of London, Botanical Journal of the Linnean Society , 2002, 140 , 415–426. 相似文献
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We have shown by electron microscopy that ammonia activation of Paracentrotus lividus eggs alters the inner ultrastructure of cortical granules. If activated eggs are inseminated, they fail to undergo a typical cortical reaction. 相似文献
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VIKRAM PATEL MARIO MAJ ALAN J. FLISHER MARY J. DE SILVA MIRJA KOSCHORKE MARTIN PRINCE WPA Zonal Member Society Representatives 《World psychiatry》2010,9(3):169-176
The treatment gap for people with mental disorders exceeds 50% in all countries
of the world, approaching astonishingly high rates of 90% in the least resourced
countries. We report the findings of the first systematic survey of leaders
of psychiatry in nearly 60 countries on the strategies for reducing the treatment
gap. We sought to elicit the views of these representatives on the roles of
different human resources and health care settings in delivering care and
on the importance of a range of strategies to increase the coverage of evidence-based
treatments for priority mental disorders for each demographic stage (childhood,
adolescence, adulthood and old age). Our findings clearly indicate three strategies
for reducing the treatment gap: increasing the numbers of psychiatrists and
other mental health professionals; increasing the involvement of a range of
appropriately trained non-specialist providers; and the active involvement
of people affected by mental disorders. This is true for both high income
and low/middle income countries, though relatively of more importance in the
latter. We view this survey as a critically important first step in ascertaining
the position of psychiatrists, one of the most influential stakeholder communities
in global mental health, in addressing the global challenge of scaling up
mental health services to reduce the treatment gap. 相似文献
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