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51.
Heald AH Sharma R Anderson SG Vyas A Siddals K Patel J Bhatnagar D Prabharkaran D Rudenski A Hughes E Durrington P Gibson JM Cruickshank JK 《Public health nutrition》2005,8(6):620-627
BACKGROUND: The insulin-like growth factor (IGF) system is implicated in the pathogenesis of diabetes and cardiovascular disease. OBJECTIVE: We report the effects of total energy intake on the IGF system in two populations with markedly different dietary macronutrient intake and cardiovascular event rate. DESIGN, SUBJECTS AND SETTING: Dietary macronutrient intake was measured in a specific Gujarati migrant community in Sandwell, UK (n=205) compared with people still resident in the same villages of origin in India (n=246). Fasting IGF-I, IGF-binding protein (IGFBP)-1 and IGFBP-3, insulin and glucose (0 and 2-hour) were measured. RESULTS: Total energy and total fat intake were higher in UK migrants, as were IGFBP-3 and IGF-I (mean (95% confidence interval): 145.9 (138.1-153.6) vs. 100.9 (94.6-107.3) ng ml(-1); F=76.6, P<0.001). IGFBP-1 was lower in UK migrants (29.5 (25.9-33.0) vs. 56.5 (50.6-62.5) microg l(-1); F=48.4, P<0.001). At both sites, IGF-I correlated positively with total energy (Spearman's rho=0.45, P<0.001) and total fat (rho=0.44, P<0.001) as did IGFBP-3 with total energy (rho=0.21, P<0.05) and fat (rho=0.26, P<0.001). Conversely, in Indian Gujaratis, IGFBP-1 fell with increasing total energy (rho=-0.27, P<0.001) and fat intake (rho=-0.26, P<0.01) but not in UK Gujaratis. Multiple linear regression modelling showed that increasing quartiles of fat intake were associated with higher IGF-I (beta=0.42, P=0.007) independent of age, body mass index, plasma insulin, fatty acids and 2-hour glucose. CONCLUSION: In these genetically similar groups, migration to the UK and adoption of a different diet is associated with marked changes in the IGF system, suggesting that environmental factors profoundly modulate serum concentrations and actions of IGFs. 相似文献
52.
AbstractRoot chicory is mainly grown in Belgium and the Netherlands with production also elsewhere in Europe, India, and South Africa. The world’s crop is worth an estimated US$56.04 million. India and South Africa focus on supplying root chicory to the blend coffee industry. Only limited and variable information is available on the fertilizer requirements of root chicory. Most studies on nitrogen (N) report that chicory in cooler, temperate regions requires 40–75?kg?N/ha compared to 200?kg?N/ha in warmer areas. Recommended rates for phosphorus (P) range from 0 to 69?kg?P/ha. Poor responses to potassium (K) are reported with recommended rates from 0 to 190?kg?K/ha. Application rates for sulfur (S) of 10–30?kg?S/ha have been suggested. Suitable micronutrient requirements and soil acid saturation and pH values for root chicory have not been published. To establish crop norms a concerted effort is needed to quantify the fertilizer use of root chicory. 相似文献
53.
Abstract. The aluminium (Al), iron (Fe) and Dissolved Organic Carbon (DOC) contents of the soil solution were monitored in two upland grassland and afforested podzol soils in Mid-Wales. Al organo-metallic complexes predominated in the O horizon leachates of the grassland soil, whereas inorganic monomeric Al forms dominated in the lower mineral horizons. Dissolved organic matter determines the chemistry, solubility, and transport of Al and Fe in the O horizon, and these are under strong biological control. The distributions of organic-Al, Fe and DOC within the soil profile were consistent with traditional podzolization theory. Observed increases in the molar ratios of Al:DOC in solution in the lower soil horizons may be responsible for the small solubility of Al organo-metallic complexes in those horizons. Afforestation increased the concentrations of organic-Al and Fe in the soil solution as compared with the concentrations observed for the grassland soil. Clearcutting further significantly mobilized Al and Fe from the upper soil horizon, primarily by increasing the DOC concentration in the soil water. 相似文献
54.
Gregory O. Hughes Wilfried Thuiller Guy F. Midgley Kai Collins 《Biological conservation》2008,141(1):23-34
Declining population numbers coupled with the growing evidence of global change have focussed attention on the critically endangered riverine rabbit (Bunolagus monticularis) endemic to South Africa. The aim of this study is to develop a habitat model to aid in the identification of isolated populations, offer opportunities for re-introduction or introduction, and guide future conservation efforts by assessing the possible impacts of global change. We attempt a novel approach where plant species which afford the riverine rabbit cover from predation and its primary food sources are modelled utilising the same technique and are included as a predictor variable in the habitat model for both current and future projections of potential habitat. Inclusion of this proximal variable as well as riparian areas yields a more parsimonious habitat model than using climatic variables alone. Results suggest that unsurveyed suitable habitat east of Victoria West might harbour previously overlooked isolated populations or offer new opportunities for re-introductions. Future climatic conditions under the most severe general circulation model for the region (HADCM3) suggest that, on average, in excess of 96% of the current habitat could become unsuitable, mitigated only slightly by a possible 7% increase in range in adjacent upper catchment areas. Consideration of existing land transformation increases this range reduction by a further 1%. Given that ex situ captive breeding programmes have met with no success and that the bulk of future potential range lies well outside of the currently known and surveyed areas the current adaptation options of conservancy establishment and captive breeding need to be re-evaluated. Without positive human intervention the future of the critically endangered riverine rabbit under conditions of global change seems certain. 相似文献
55.
Kevin A. Hughes Kerstin Scherer Petra Rettberg Pete Convey 《Soil biology & biochemistry》2006,38(6):1488-1490
In the Arctic, seasonal ozone depletion is resulting in periods of enhanced UV-B radiation at ground level while regional climate change is associated with increasing temperatures. These changes are likely to alter plant distribution, biodiversity and morphology, which may have knock-on effects for microbially driven biogeochemical cycling and other soil processes. Our study examined the transmission of solar UV radiation through arctic tundra plants using a portable UV radiometer and the DLR-biofilm biological UV dosimeter. A strong negative correlation was found between vegetation cover and UV transmission to the soil surface. Penetration of UV to the soil beneath tundra plants varied depending upon plant morphology, being greater through low creeping plants than cushion plants, grasses or mosses. UV transmission to the soil surface beyond the foliage edge also varied with plant morphology and the presence of flowers. 相似文献
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57.
Faith E. Hughes DVM H. David Moll DVM MS Diplomate ACVS Donnie E. Slone DVM MS Diplomate ACVS 《Journal of Equine Veterinary Science》1996,16(4):172-175
Meconium impactions are only rarely refractory to medical therapy. The purpose of this paper is to examine the outcome of 8 foals that required an exploratory celiotomy to correct a meconium impaction. Between 1984 and 1992, 24 foals were referred with a primary diagnosis of meconium impaction. All foals were treated medically prior to and following referral. Of the 24 foals, 8 had impactions requiring surgical intervention. Exploratory celiotomies were performed, and the impaction was reduced manually or by enterotomy. Follow up information was available on 7 foals. All survived surgery and were discharged. Four of the 8 foals matured and raced. Two foals were euthanatized due to extensive serosal adhesions and one foal was euthanatized due to an unrelated orthopedic condition. Our results support the decision for an exploratory surgery only after aggressive medical therapy has failed. Several treatment options have been developed in recent years that have reduced the number of foals that may require surgery. 相似文献
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60.
Hughes CE 《Science (New York, N.Y.)》1925,61(1567):24-26