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991.
This experiment was conducted to investigate the potential risk of toxic elements in paddy soils and rice straws, bran, and husked grains in Kuchesfahan, Gilan, Iran. The average content of total and DTPA-extractable of Cd, Cu, Fe, Mn, Ni, Pb, and Zn were 7.0, 26.3, 20728.8, 1516.7, 43.8, 16.6, and 211.8?mg kg?1, and 0.32, 14.1, 97.3, 63.4, 1.7, 4.8, and 56.2?mg kg?1, respectively. In addition, the average content of Cd, Cu, Fe, Mn, Ni, Pb, and Zn in rice grain was 0.16, 2.4, 135.5, 34.1, 2.0, 0.6, and 15.0?mg kg?1, respectively. The average transfer factor for Cd, Cu, Fe, Mn, Ni, Pb, and Zn from soil to straw was 0.38, 0.16, 0.004, 0.13, 0.3, 0.04, and 0.09, respectively. The average values of estimated daily intake for Cd, Cu, Fe, Mn, Ni, Pb, and Zn through rice consumption for adult are respectively, estimated to be 0.0004, 0.005, 0.32, 0.08, 0.005, 0.0015, and 0.035?mg kg?1 body weight per day. There was no health risk index (HRI) values for adult greater than 1 (except three samples for Fe, and one sample for Mn and Cd); indicated that intake of single metal through the consumption of rice was safe. The average of heath index (HI) value for rice consumption was 0.33 and 0.35 for adult and children, respectively. Therefore, combination of several potentially toxic elements may not cause risk to local residents. Spatial distributions of HRI were obtained for potentially toxic metals in husked grains. 相似文献
992.
Shamina M. Rangwala Katharine D’Aquino Yue-Mei Zhang Lindsay Bader Wilson Edwards Songmao Zheng Annette Eckardt Ann Lacombe Rebecca Pick Veronica Moreno Lijuan Kang Wenying Jian Eric Arnoult Martin Case Celia Jenkinson Ellen Chi Ronald V. Swanson Paul Kievit James N. Leonard 《Cell metabolism》2019,29(4):837-843.e5
993.
目的:分析妊娠期糖尿病患者孕前身体质量指数(Body Mass Index,BMI)与血糖水平及膳食营养摄入的相关性。方法:选择2017年1月-2018年1月于我院治疗的妊娠期糖尿病患者86例作为观察组,另选择血糖水平正常的孕妇60例作为对照组,并依据BMI不同将观察组分为A组(BMI18.5 kg/m~2)、B组(18.5 kg/m~2≤BMI24.0 kg/m~2)、C组(24.0 kg/m~2≤BMI≤28.0 kg/m~2)、D组(BMI28.0 kg/m~2)。比较各组孕前BMI、血糖水平及膳食营养摄入情况。结果:观察组孕前体重、BMI、脂肪供能比均显著高于对照组,碳水化合物摄入量及碳水化合物供能比低于对照组,差异均有统计学意义(P0.05);各组空腹时、餐后2 h血糖水平以及每日能量、脂肪摄入比较结果显示:D组C组B组A组,且组间差异均有统计学意义(P0.05)。结论:孕前BMI与血糖水平及膳食营养摄入存在一定相关性,控制合理体重、保持营养均衡对于降低妊娠期糖尿病发生率具有重要意义。 相似文献
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996.
Movement Patterns of Frugivorous Birds Promote Functional Connectivity among Chaco Serrano Woodland Fragments in Argentina 下载免费PDF全文
María Celeste Díaz Vélez Wesley R. Silva Marco A. Pizo Leonardo Galetto 《Biotropica》2015,47(4):475-483
Movement patterns of frugivorous birds may be altered in anthropogenically fragmented landscapes, with possible consequences for seed dispersal and plant recruitment. We studied the movement patterns and functional connectivity of six frugivorous bird species (Colaptes melanochloros, Thraupis bonariensis, Pitangus sulphuratus, Saltator aurantiirostris, Turdus amaurochalinus, and Elaenia spp.) in a fragmented Chaco‐woodland landscape in Argentina. We recorded the directions of bird movements (arrivals and departures) and whether their destination was oriented toward a specific neighboring fragment. We evaluated the movement rates, distance of interpatch movement, and functional connectivity within the landscape for the six bird species. We applied a novel approach, graph theory, to represent bird movement patterns in the landscape and the functional connections among fragments for each bird species. Bird movements were recorded at point‐count stations established along the edges of each fragment. The directions of arrival and departure movements from and to neighboring fragments revealed complex movement patterns. However, the destination of bird movements after leaving the focal fragments was usually concentrated on only a few neighboring fragments of different sizes. Pitangus sulphuratus and T. bonariensis showed larger movement rates and higher functional connectivity (number of graphs and functional area) than the other frugivorous species. The functional connectivity mediated by movement of frugivorous birds may promote seed dispersal of many bird‐dispersed plant species. As forest loss and fragmentation of Chaco subtropical forests increase, understanding the pivotal role of mobile links exerted by avian seed dispersers is vital to maintaining and conserving this unique ecosystem. 相似文献
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Eight trials were conducted in commercial potato fields infested with the white potato cyst nematode (wPCN, Globodera pallida) and one in a field infested with the yellow PCN (yPCN, Globodera rostochiensis). Our aims were to produce data to validate and refine a computer‐based program (The Model) for the long‐term management of PCN, to determine nematicide effectiveness and to assess rates of PCN population decline between potato crops. Prior to planting, each farmer applied an overall nematicide treatment to his field, except for ten untreated plots that were widely spaced to encompass a range of PCN population densities. Each untreated plot was paired with a similar plot in the adjacent treated area and all plots were intensively sampled for PCN population densities at planting (Pi) and again at harvest (Pf) when tuber yields were determined. Four trials were re‐sampled 2–4 years later to determine PCN population decline rates. Regressions that form the basis of ‘The Model’ and described the relationship between Pi and tuber yield and PCN population density at harvest were fitted to the results from both the untreated and nematicide treated plots. These regressions also enabled us to estimate the yield potential at each site in the absence of PCN and showed that nematicide treatment generally did not increase yield potential and that both tuber yield and PCN multiplication decreased with increasing Pi. However, there were major differences between sites and cultivars. When untreated, the yield of cv. Maris Piper was hardly affected in a highly organic soil with Pi > 200 eggs g?1 whereas the yield of partially resistant cv. Santé was decreased from a potential of c. 60 t ha?1 to c. 20 t ha?1 in a light silt with Pi = 20 egg g?1 soil. Similarly, untreated wPCN multiplication rates at a low Pi ranged from 46‐fold to >100‐fold. Nematicide effectiveness was estimated from the regressions and, at several sites, yield was decreased despite nematicide treatment. Control of wPCN multiplication was even poorer. In only two of seven trials planted with susceptible cultivars was more than 50% control achieved – maximum populations in treated plots usually exceeded 250 eggs g?1. Partially resistant Santé decreased the multiplication rate of wPCN in the two trials where it was planted. An alternative analysis using Genstat indicated that The Model tended to underestimate the maximum multiplication rate and overestimate the maximum population density. When four sites were re‐sampled 2–4 years after harvest the populations of wPCN had declined by between 15% and 33.5% per annum with a mean of 26% per annum. Modelling indicated that rotations longer than 8 years were required to control wPCN unless other effective control measures, such as growing a partially resistant cultivar, were used. 相似文献
999.
Shin Akakura Elena Ostrakhovitch Reiko Sanokawa-Akakura Siamak Tabibzadeh 《Biochemical and biophysical research communications》2014
Instead of relying on mitochondrial oxidative phosphorylation, most cancer cells rely heavily on aerobic glycolysis, a phenomenon termed as “the Warburg effect”. We considered that this effect is a direct consequence of damage which persists in cancer cells that recover from damage. To this end, we studied glycolysis and rate of cell proliferation in cancer cells that recovered from severe damage. We show that in vitro Damage-Recovered (DR) cells exhibit mitochondrial structural remodeling, display Warburg effect, and show increased in vitro and in vivo proliferation and tolerance to damage. To test whether cancer cells derived from tumor microenvironment can show similar properties, we isolated Damage-Recovered (TDR) cells from tumors. We demonstrate that TDR cells also show increased aerobic glycolysis and a high proliferation rate. These findings show that Warburg effect and its consequences are induced in cancer cells that survive severe damage. 相似文献
1000.
This article is part of a Special Issue “Energy Balance”. 相似文献