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Shirazki A Weintraub Z Reich D Gershon E Leshem M 《American journal of physiology. Regulatory, integrative and comparative physiology》2007,292(4):R1683-R1689
Forty-one children aged 10.5 +/- 0.2 years (range, 8.0-15.0 yr), born with low birth weight of 1,218.2 +/- 36.6 g (range, 765-1,580 g) were selected from hospital archives on the basis of whether they had received neonatal diuretic treatment or as healthy matched controls. The children were tested for salt appetite and sweet preference, including rating of preferred concentration of salt in tomato soup (and sugar in tea), ratings of oral spray (NaCl and sucrose solutions), intake of salt or sweet snack items, and a food-seasoning, liking, and dietary questionnaire. Results showed that sodium appetite was not related to neonatal diuretic treatment, birth weight, or gestational age. However, there was a robust inverse correlation (r = -0.445, P < 0.005) between reported dietary sodium intake and the neonatal lowest serum sodium level (NLS) recorded for each child as an index of sodium loss. The relationship of NLS and dietary sodium intake was found in both boys and girls and in both Arab and Jewish children, despite marked ethnic differences in dietary sources of sodium. Hence, low NLS predicts increased intake of dietary sodium in low birth weight children some 8-15 yr later. Taken together with other recent evidence, it is now clear that perinatal sodium loss, from a variety of causes, is a consistent and significant contributor to long-term sodium intake. 相似文献
994.
Xu X Weitzberg M Keyes RF Li Q Wang R Wang X Zhang X Frevert EU Camp HS Beutel BA Sham HL Gu YG 《Bioorganic & medicinal chemistry letters》2007,17(6):1803-1807
The structure-activity relationship study focused on the polar region of the HTS hit A-80040 (1) producing several series of potent and selective ACC2 inhibitors. The SAR suggests a compact lipophilic pocket that does not tolerate polar and ionic groups. Replacement of the hydroxyurea group with isoxazoles improves ACC2 selectivity while maintaining potency. Variations at the propargylic site of 11a reduce ACC2 potency. 相似文献
995.
Vitis vinifera L. cv. ‘Thompson Seedless’ presents a type of stenospermocarpy in grape where fertilization occurs but seeds abort and fail
to develop. To unravel the molecular basis for stenospermocarpy in grapes, subtractive hybridization was carried out in order
to isolate differentially regulated genes that participate in the seedlessness machinery. Two ‘Thompson’ lines, a seeded and
a seedless, were screened during different flower developmental stages. One of the genes, that was differentially expressed
between the seeded and seedless lines, was the chloroplast chaperonin 21 (ch-Cpn21). ch-Cpn21 is a 21-kDa co-chaperonin polypeptide
formed by two GroES-like domains fused together in tandem. Silencing of ch-Cpn21 in Nicotiana
benthamiana plants resulted in leaf stunting, chlorosis, as well as ovary necrogenesis leading to seed abortion. Moreover, organ-specific
silencing of ch-Cpn21 only in Lycopersicum esculentum fruits resulted in the development of seedless tomatoes. These results suggest that ch-Cpn21 may play a role in seed abortion
in stenospermocarpic grapes. 相似文献
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Epigenetic mechanisms of perinatal programming of hypothalamic-pituitary-adrenal function and health 总被引:1,自引:0,他引:1
Environmental effects on the materno-foetal interaction determine birth outcomes that predict health over the lifespan. Thus, maternal undernutrition or stress associate with low birth weight, leading to an increased risk of metabolic and cardiovascular illness in the offspring. We argue that these effects are, in part, mediated by direct and indirect effects on the hypothalamic-pituitary-adrenal (HPA) axis such that (i) the effect of maternal adversity on foetal growth is mediated by adrenal glucocorticoids and (ii) environmental adversity alters maternal physiology and behaviour, which then programs HPA activity in the offspring. 相似文献
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Reduction of oscillations in population size is of fundamental importance to both theoretical and applied ecology. Spatial variability in population rates among different habitat regions is known to be an important mechanism that inhibits oscillations in population size. In the current study we used an individual-based model to simulate a single population of animals whose individual members are sensitive to competition only within their vicinity (i.e., within their competition neighborhood, CN). Our model extends previous studies by exploring how local interactions reduce population oscillations in competitive systems of animals, rather than in systems of plants. Our simulations explored the effects of animal mobility and interaction range separately on population dynamics. In our model, a decrease in CN dimensions tended to reduce population oscillations at all tested animal movement speeds. Yet, movement speed affected animal distribution patterns; an increase in movement speed led to more random distributions. We also found that mean population size was affected more by CN dimensions at lower mobility levels than when it was high. 相似文献