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101.
D.G. Valencia M.P. SerranoR. Lázaro M.A. LatorreG.G. Mateos 《Animal Feed Science and Technology》2008
Two trials were conducted to test the effect of micronization (very fine grinding) of soya bean meal (SBM) and fullfat soya bean (FFSB) on productive performance and digestive traits of piglets. The experimental design was completely randomized with four treatments arranged factorially (SBM and FFSB, micronized and ground). The mean particle size (MPS) was 47 and 881 μm for the SBM and 41 and 778 μm for the FFSB, micronized and ground, respectively. In trial 1 growth traits from 23 to 45 days of age and the coefficient of total tract apparent digestibility (CTTAD) of dietary components at 33 and 45 days of age were assessed. In trial 2 the coefficient of ileal apparent digestibility (CIAD) of dietary components, the pH of the gastro intestinal tract (GIT) and the weight of digestive organs and spleen were measured at 45 days of age. From 23 to 33 days of age pigs fed SBM grew faster (253 g/d versus 213 g/day; P<0.05) and were more efficient (0.87 g/g versus 0.98 g/g; P<0.01) than pigs fed FFSB. For the entire experiment (23–45 days of age) pigs fed SBM tended to grow more (360 g/day versus 324 g/day) and to eat more feed (414 g/day versus 380 g/day) than pigs fed FFSB (P<0.10). The CTTAD of crude protein (0.798 g/kg versus 0.778 g/kg), organic matter (0.864 g/kg versus 0.839 g/kg) and gross energy (0.849 g/kg versus 0.830 g/kg) were higher for pigs fed SBM than for pigs fed FFSB (P<0.001). In addition, CIAD of organic matter (0.765 g/kg versus 0.705 g/kg) and gross energy (0.761 g/kg versus 0.711 g/kg) were higher for SBM than for FFSB diets (P<0.001). The pH of the different segments of the GIT was not affected by the protein source (P>0.10). Particle size did not affect any trait studied (P>0.10). The poor performance and digestibility of pigs fed FFSB as compared to pigs fed SBM might be related to the conditions applied during processing. It is concluded that pigs fed soya bean meal perform better than pigs fed FFSB and that micronization of the soya protein sources does not affect any trait studied. 相似文献
102.
A potentially 18 donor macrocyclic ligand bearing four acetohydrazide pendant arms has been used to synthesize nine new dinuclear metal complexes with Co(II), Ni(II), Cu(II), Zn(II) and Cd(II). All compounds have been characterized by elemental analysis, MALDI-TOF-MS and FAB spectrometry, and by IR, UV-Vis and NMR spectroscopy. The system is a very good candidate for in situ recognition effects by MALDI-TOF-MS spectrometry and absorption spectroscopy. The presence of four acetohydrazide groups in L allows the synthesis of new three-dimensional self-assembling ditopic supramolecular compounds. 相似文献
103.
104.
It is well known that pulp density and particle size determine the available surface area concentration and have an influence
in the overall rate of bioleaching of minerals. As metal solubilization takes place through the surface area of the particles,
it can be expected that different combinations of pulp densities and particle sizes giving the same surface area concentration
would determine the same leaching rate. The objective of this work was to test this hypothesis on the effect of surface area
concentration, pulp density and particle size of the biooxidation of a pyritic gold concentrate by the thermophilic Archaeon
Sulfolobus metallicus in shake flasks. The gold concentrate was used at 2.5%, 5%, 10%, and 15% w/v pulp density and at four size fractions: 150–106,
106–75, 75–38 and –38 μm. Temperature was 68°C and the initial pH was 2.0. Results showed that the volumetric productivities
of iron and sulfate depend not only on the surface area concentration but also on pulp density and particle size considered
separately. These two variables not only determine surface area but also exert additional effects on the process, so the hypothesis
was not confirmed. Maximum attained iron productivity was 1.042 g/l day with the 75–38 μm fraction at 5% pulp density. Maximum
sulfate productivity was 4.279 g/l day with the 75–38 μm fraction at 10% pulp density. 相似文献
105.
Rodolfo Ocadiz-Delgado Alberto Marroquin-Chavira Ruth Hernandez-Mote Concepción Valencia M. Eugenia Manjarrez-Zavala Luis Covarrubias Patricio Gariglio 《Transgenic research》2009,18(4):513-527
Squamous cell carcinoma (SCC) of the oral cavity is one of the most common neoplasms in the world. During the past 2 decades,
the role of high-risk human papilloma virus (HR-HPV) has been studied and the data supporting HPV as a one of the causative
agents in the development and progression of a sub-set of head and neck squamous cell carcinomas (HNSCC) has accumulated.
In order to investigate the role of HR-HPV oncogene expression in early epithelial alterations in vivo, we produced transgenic
mice expressing HPV16 early region genes from the promoter of the bovine keratin 6 gene (Tg[bK6-E6/E7]). In this article,
we demonstrate that E6/E7 transgene was abundantly expressed and cellular proliferation was increased in the middle tongue
epithelia of transgenic mice, and that in the same region young (27 weeks old) Tg[bK6-E6/E7] mice spontaneously developed
histological alterations, mainly focal epithelial hyperplasia (FEH). 相似文献
106.
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108.
Molecular networks are being used to reconcile genotypes and phenotypes by integrating medical information. In this context, networks will be instrumental for the interpretation of disease at the personalized medicine level. 相似文献
109.
Anaïs Baudot Francisco X. Real José M. G. Izarzugaza Alfonso Valencia 《EMBO reports》2009,10(4):359-366
Cancer genome projects are now being expanded in an attempt to provide complete landscapes of the mutations that exist in tumours. Although the importance of cataloguing genome variations is well recognized, there are obvious difficulties in bridging the gaps between high‐throughput resequencing information and the molecular mechanisms of cancer evolution. Here, we describe the current status of the high‐throughput genomic technologies, and the current limitations of the associated computational analysis and experimental validation of cancer genetic variants. We emphasize how the current cancer‐evolution models will be influenced by the high‐throughput approaches, in particular through efforts devoted to monitoring tumour progression, and how, in turn, the integration of data and models will be translated into mechanistic knowledge and clinical applications. 相似文献
110.
Philip T. Liu Mirjam Schenk Valencia P. Walker Paul W. Dempsey Melissa Kanchanapoomi Matthew Wheelwright Aria Vazirnia Xiaoran Zhang Andreas Steinmeyer Ulrich Zügel Bruce W. Hollis Genhong Cheng Robert L. Modlin 《PloS one》2009,4(6)
Antimicrobial effector mechanisms are central to the function of the innate immune response in host defense against microbial pathogens. In humans, activation of Toll-like receptor 2/1 (TLR2/1) on monocytes induces a vitamin D dependent antimicrobial activity against intracellular mycobacteria. Here, we report that TLR activation of monocytes triggers induction of the defensin beta 4 gene (DEFB4), requiring convergence of the IL-1β and vitamin D receptor (VDR) pathways. TLR2/1 activation triggered IL-1β activity, involving the upregulation of both IL-1β and IL-1 receptor, and downregulation of the IL-1 receptor antagonist. TLR2/1L induction of IL-1β was required for upregulation of DEFB4, but not cathelicidin, whereas VDR activation was required for expression of both antimicrobial genes. The differential requirements for induction of DEFB4 and cathelicidin were reflected by differences in their respective promoter regions; the DEFB4 promoter had one vitamin D response element (VDRE) and two NF-κB sites, whereas the cathelicidin promoter had three VDREs and no NF-κB sites. Transfection of NF-κB into primary monocytes synergized with 1,25D3 in the induction of DEFB4 expression. Knockdown of either DEFB4 or cathelicidin in primary monocytes resulted in the loss of TLR2/1-mediated antimicrobial activity against intracellular mycobacteria. Therefore, these data identify a novel mechanism of host defense requiring the induction of IL-1β in synergy with vitamin D activation, for the TLR-induced antimicrobial pathway against an intracellular pathogen. 相似文献