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131.
Liu Y Zhou D Zhang Z Song Y Zhang D Zhao T Chen Z Sun Y Zhang D Yang Y Xing Q Zhao X Xu H He L 《Journal of lipid research》2011,52(2):354-360
A number of recent genome-wide association (GWA) studies have identified several novel genetic determinants of plasma lipid and lipoprotein concentrations in European populations. However, it is still unclear whether these loci identified in Caucasian GWA studies also exert the same effect on lipid and lipoprotein concentrations in a Chinese population. We genotyped 10 single-nucleotide polymorphisms (SNPs) in nine loci in a Chinese Han population sample (n = 4,192) and assessed the associations of these SNPs with metabolic traits, using linear regression adjusted for age, gender, diabetes status, and body mass index. Three variants (rs12654264, P ~ 1.7 × 10(-6); rs3764261, P ~ 7.1 × 10(-7); and rs4420638, P ~ 1.1 × 10(-3)) showed strong evidence for association with total cholesterol; four variants (rs780094, P ~ 1.8 × 10(-11); rs17145738, P ~ 5.0 × 10(-7); rs326, P ~ 2.3 × 10(-6); and rs439401, P ~ 2.2 × 10(-5)) showed strong evidence for association with triglycerides, four variants (rs17145738, P ~ 1.9 × 10(-4); rs326, P ~ 9.7 × 10(-4); rs1800588, P ~ 1.5 × 10(-7); and rs3764261, P ~ 4.3 × 10(-14)) showed strong evidence for association with HDL-cholesterol (HDL-C), two variants (rs12654264, P ~ 2.3 × 10(-5); and rs4420638, P ~ 3.6 × 10(-4)) showed strong evidence for association with LDL-C, and four variants (rs326, P ~ 2.8 × 10(-3); rs1800588, P ~ 6.1 × 10(-4); rs3764261, P ~ 2.0 × 10(-3); and rs4420638, P ~ 9.4 × 10(-5)) showed strong evidence for association with total cholesterol-HDL-C-related ratio. These SNPs generated strong combined effects on lipid traits and dyslipidemia. Our findings indicate that the variants that associated with metabolic traits in Europeans may also play a role in a Chinese Han population. 相似文献
132.
《Animal : an international journal of animal bioscience》2014,8(4):660-666
The aim of this study was to investigate whether fatty acid (FA) profile, oxidative stability of lipids and other meat quality traits differed between high (HW: 1.8 to 2.2 kg) and low (LW: 0.8 to 1.2 kg) birth weight piglets. Forty new-born male pigs (n=20 HW, n=20 LW) were reared in separate pens until the finishing period, when they were slaughtered at 150 days of age, and pH and temperature were measured in the carcass. Afterwards, the Longissimus dorsi muscle was excised from the carcass, and samples were collected for subsequent meat quality analyses (thaw loss, cooking loss, shear force, chemical analysis and sensory analysis for tenderness). Birth weight had minor impacts on meat quality traits, which were limited to higher shear force in the LW group (P<0.01). Chemical components (moisture, protein, fat, ash), cholesterol levels and lipid oxidation (thiobarbituric acid-reactive substances) were not affected by birth weight (P>0.05). FA profile and the amount of saturated, monounsaturated and polyunsaturated fatty acids were similar, but HW pigs had higher atherogenic index than their LW counterparts (P<0.01). Notwithstanding the higher shear force presented by the lower birth weight pigs, in the sensory test, the panelists did not detect any differences in the tenderness of pork from HW and LW animals. Therefore, our results suggest that low birth weight has minimal impact on meat quality. 相似文献
133.
134.
The tRNA adaptation index (tAI) is a widely used measure of the efficiency by which a coding sequence is recognized by the intra-cellular tRNA pool. This index includes among others weights that represent wobble interactions between codons and tRNA molecules. Currently, these weights are based only on the gene expression in Saccharomyces cerevisiae. However, the efficiencies of the different codon–tRNA interactions are expected to vary among different organisms. In this study, we suggest a new approach for adjusting the tAI weights to any target model organism without the need for gene expression measurements. Our method is based on optimizing the correlation between the tAI and a measure of codon usage bias. Here, we show that in non-fungal the new tAI weights predict protein abundance significantly better than the traditional tAI weights. The unique tRNA–codon adaptation weights computed for 100 different organisms exhibit a significant correlation with evolutionary distance. The reported results demonstrate the usefulness of the new measure in future genomic studies. 相似文献
135.
Summary Foundresses of two species of Japanese paper wasps,Polistes chinensis antennalis andP. jadwigae, attacked other colonies of the same species. A foundress ofP. chinensis antennalis visited two nests of the same species, and ate larvae from them, while two foundresses ofP. jadwigae each visited a nest of the same species, eating larvae and pupae even when the foundress of the attacked nest was on her
nest. In addition, a foundress ofP. jadwigae distributed flesh balls thus obtained among their larvae. Discussion was made on the adaptive significance of the inter-colonial
cannibalism. It was considered that, at first, it increases the foraging efficiency and secondly it plays a role in regulating
population density. 相似文献
136.
Russell Dinnage Marc W. Cadotte Nick M. Haddad Gregory M. Crutsinger David Tilman 《Ecology letters》2012,15(11):1308-1317
Large‐scale habitat destruction and climate change result in the non‐random loss of evolutionary lineages, reducing the amount of evolutionary history represented in ecological communities. Yet, we have limited understanding of the consequences of evolutionary history on the structure of food webs and the services provided by biological communities. Drawing on 11 years of data from a long‐term plant diversity experiment, we show that evolutionary history of plant communities – measured as phylogenetic diversity – strongly predicts diversity and abundance of herbivorous and predatory arthropods. Effects of plant species richness on arthropods become stronger when phylogenetic diversity is high. Plant phylogenetic diversity explains predator and parasitoid richness as strongly as it does herbivore richness. Our findings indicate that accounting for evolutionary relationships is critical to understanding the severity of species loss for food webs and ecosystems, and for developing conservation and restoration policies. 相似文献
137.
Summary Studies were conducted in 22 non-calcareous soils (India) to evaluate various extractants,viz. (6N HCl, 0.1N HCl, EDTA (NH4)2CO3, EDTA NH4OAc, DTPA+CaCl2 and 1M MgCl2) to find critical levels of soil and plant Zn for green gram (Phaseolus aureus Roxb.). The order of extractability by the different extractants was 6N HCl>0.1N HCl>EDTA (NH4)2CO3<EDTA NH4OAc DTPA+CaCl2>1M MgCl2.
Critical levels of 0.48 ppm DTPA × CaCl2 extractable Zn, 0.80 ppm EDTA NH4OAc extractable Zn, 0.70 ppm EDTA (NH4)2CO3 extractable Zn, and 2.2 ppm 0.1N HCl extractable Zn were estimated for the soils tested. The critical Zn concentration in 6 weeks old plants was found to
be 19 ppm. The 0.1N HCl method gave the best correlation (r=0.588**) between extractable Zn and Bray's per cent yield, while with DTPA+CaCl2, it was slightly low (r=0.542**). The DTPA + CaCl2 method gave significant (r=0.73**) correlation with plant Zn concentration. The 0.1N HCl gave the higher correlation with Zn uptake (r=0.661**) than DTPA (r=0.634**) 6N HCl and 1M MgCl2 method gave nonsignificant positive relationship with Bray's per cent yield. For noncalcareous soils apart from the common
use of DTPA+CaCl2, 0.1N HCl can also be used for predicting soil available Zn. The use of 0.1N HCl would be much cheaper than DTPA and other extractants used in the study. 相似文献
138.
土壤砷污染是一种十分严重的环境问题,但目前尚无经济有效的治理方法。利用各种重金属的耐性与富集植物修复重金属污染土壤是当前的研究热点。通过对两个中国典型的砷矿区(炼砷区)土壤与植物的系统调查与采样分析,发现若干种植物对砷具有极强的耐性和不同程度的富集能力。砷在不同植物中的含量分别为:蜈蚣草(Pteris vittata)羽片1 600 mg·kg-1 DW,剑叶凤尾蕨(Pteris ensiformis)地上部1 230 mg·kg-1 DW,酸模(Rumex acetosa)地上部 440 mg·kg-1 相似文献
139.
Rafael Balaña Fouce Maria I. Escribano Jose M. Alunda 《Molecular and cellular biochemistry》1991,107(2):127-133
Summary The putrescine uptake/efflux regulation and their regulatory role on intracellular polyamine pools have been studied in the parasitic protozoa Leishmania infantum. Putrescine uptake was age-dependent with maximal values in logarithmic phase promastigotes and minimal in stationary phase. Moreover, putrescine uptake was activated in response to depletion of intracellular polyamines by alpha-difluoromethylornithine (DFMO) — a well known irreversible enzyme-activated inhibitor of ornithine decarboxylase. Kinetic studies of putrescine uptake induction showed a notable rise in Vmax without Km changes, suggesting a de novo synthesis of putrescine carriers. Putrescine uptake was able to replenish polyamine content and also to recover the proliferative rate in cells treated during 24 hours with DFMO. 相似文献
140.
Lorenz R. Rhomberg 《人类与生态风险评估》2009,15(6):1099-1145
For acute inhalation toxicity assessment, I develop a conceptual framework for expressing combinations of intensity (air concentration) and duration that produce equivalent toxicity by examining how the shape of the body-burden uptake curve during a bout of inhalation interacts with various pharmacodynamic measures of the critical body burden needed to produce toxicity. If toxicity depends on attaining a critical tissue concentration, three existing empirical approaches—Haber's Law, the ten Berge equation, and pure air-concentration-dependence—are but local approximations to different parts of an overarching mathematical relationship. The compound-specific half-life of elimination determines the range of durations for which each applies: durations of one half-life or shorter follow Haber's Law, exposures of 4 or more half-lives follow pure air-concentration-dependence, and intermediate durations can be approximated by the ten Berge equation. Better animal-to-human extrapolation is achieved if exposure durations are expressed as number of species-specific half-lives. I consider several alternative pharmacodynamic criteria, such as the dependence of toxicity on time spent above a critical tissue concentration, or on the area under the tissue concentration curve, on the tissue concentration of a toxic metabolite, or on the imbalance of damage and repair processes. 相似文献