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61.
M Harmsen TA Oosterlaken C Tangerman H Snippe CA Kraaijeveld 《Canadian Metallurgical Quarterly》1993,43(2):137-146
3-Hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase (EC 1.1.1.34) is the rate limiting step in the mevalonate pathway that produces isoprenoids and cholesterol. Inhibitors of HMG-CoA reductase are teratogenic in vivo and induce neural tube defects in rat embryo culture, effects which appear unrelated to cholesterol deficiency. This study is the first to localize HMG-CoA reductase mRNA by in situ hybridization (ISH). Expression of reductase mRNA was examined in post-implantation rat embryos, and for control purposes in rat liver and UT-1 cells, using a digoxigenin-11 (dig-11) labelled cRNA probe. Eighteen-day fetal liver showed heavy but patchy hybridization, and adult rat liver showed strong hybridization only on some periportal hepatocytes, which was absent in livers of fasted animals. UT-1 cells stimulated to overexpress HMG-CoA reductase mRNA were strongly positive with the same probe. Control hybridizations with sense strand RNA probe, or with cRNA probe on pre-RNased tissue were negative. Strong hybridization signal for HMG-CoA reductase mRNA was observed in all tissues of the post-implantation rat embryo, from egg cylinder to 30 somite stages (7 to 12 days). Heavy signal was noted in primitive ectoderm and neural tube. The wide embryonic and extraembryonic distribution and abundance of HMG-CoA reductase mRNA may reflect developmental requirements for products of the mevalonate pathway, e.g., isoprenoids for post-translational farnesylation of p21ras. 相似文献
62.
Emilly Sigoli Rosangela Aline Anto Maria Paula Guerreiro Tatiana Oliveira Passos de Araújo Patty Karina dos Santos Daiane Leite da Roza Dilson E. Rassier Anabelle Silva Cornachione 《International journal of molecular sciences》2022,23(9)
Duchenne muscular dystrophy (DMD) is a muscle disease characterized by the absence of the protein dystrophin, which causes a loss of sarcolemma integrity, determining recurrent muscle injuries, decrease in muscle function, and progressive degeneration. Currently, there is a need for therapeutic treatments to improve the quality of life of DMD patients. Here, we investigated the effects of a low-intensity aerobic training (37 sessions) on satellite cells, peroxisome proliferator-activated receptor-gamma coactivator (PGC)-1α protein (PGC-1α), and different types of fibers of the psoas muscle from mdx mice (DMD experimental model). Wildtype and mdx mice were randomly divided into sedentary and trained groups (n = 24). Trained animals were subjected to 37 sessions of low-intensity running on a motorized treadmill. Subsequently, the psoas muscle was excised and analyzed by immunofluorescence for dystrophin, satellite cells, myosin heavy chain (MHC), and PGC-1α content. The minimal Feret’s diameters of the fibers were measured, and light microscopy was applied to observe general morphological features of the muscles. The training (37 sessions) improved morphological features in muscles from mdx mice and caused an increase in the number of quiescent/activated satellite cells. It also increased the content of PGC-1α in the mdx group. We concluded that low-intensity aerobic exercise (37 sessions) was able to reverse deleterious changes determined by DMD. 相似文献
63.
塔程程 《吉林化工学院学报》2021,38(8):76-79
信息检索课程的系统化讲授,对于大学生优化信息检索行为,提高信息检索使用效率具有不容忽视的教学辅助作用.立足问卷调查形成的一系列相关数据,探讨大学生信息检索行为存在问题,最终在课程教学中提出优化大学生信息检索的对策:明确信息检索目的,提升实施效果;有效提升检索行为实施频率,增强综合质量;使得信息获取多元发展,优化成效凸显... 相似文献
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Rachel Passos de Oliveira Santos Daniele Oliveira Castro Adhemar Coll Ruvolo‐Filho Elisabete Frollini 《应用聚合物科学杂志》2014,131(12)
This investigation focuses on the preparation of bio‐based composites from recycled poly (ethylene terephthalate) (PET) and sisal fibers (3 cm, 15 wt %), via thermopressing process. Plasticizers derived from renewable raw materials are used, namely, glycerol, tributyl citrate (TBC) and castor oil (CO), to decrease the melting point of the recycled PET (Tm ∼ 265°C), which is sufficiently high to initiate the thermal decomposition of the lignocellulosic fiber. All used materials are characterized by thermogravimetric analysis and differential scanning calorimetry, and the composites are also characterized via dynamic mechanical thermal analysis. The storage modulus (30°C) and the tan δ peak values of CT [PET/sisal/TBC] indicate that TBC also acts as a compatibilizing agent at the interface fiber/PET, as well as a plasticizer. To compare different processing methods, rheometry/thermopressing and compression molding are used to prepare the recycled PET/sisal/glycerol/CO composites. These two different methods of processing show no significant influence on the thermal properties of these composites. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40386. 相似文献
66.
This work concerns the effect of gas phase properties on incipient flooding in counter-current gas–liquid two-phase flow in small diameter inclined tubes (D < 10 mm). The aim is to propose generalized correlations that can be used to predict incipient flooding in small diameter tubes. Experiments were performed in a 7 mm glass tube and at two inclination angles, i.e. 30 and 60° from the horizontal, using water as liquid phase and atmospheric air, He and CO2 as gas phase. Previously proposed correlations for flooding prediction ( Pantzali et al., 2008) were suitably adjusted to incorporate the effect of gas phase properties. It has been proved that the flooding curves calculated using the proposed correlations are in good agreement with both the results of the present study and relevant literature data. 相似文献
67.
Paulo Santos Diogo Peixoto Inês Ferreira Ricardo Passos Pedro Pires Marco Simes Pedro Pouso-Ferreira Teresa Baptista Benjamín Costas 《International journal of molecular sciences》2022,23(3)
Photobacteriosis is a septicaemic bacterial disease affecting several marine species around the globe, resulting in significant economic losses. Although many studies have been performed related to the pathogen virulence and resistance factors, information regarding the host defence mechanisms activated once an infection takes place is still scarce. The present study was designed to understand innate immune responses of farmed juvenile gilthead seabream (Sparus aurata) after Photobacterium damselae subsp. piscicida (Phdp) infection. Therefore, two groups of seabream juveniles were intraperitoneally injected with 100 µL of PBS (placebo) or 100 µL of exponentially growing Phdp (1 × 106 CFU/mL; infected). The blood, plasma, liver, and head kidney of six fish from each treatment were sampled immediately before infection and 3, 6, 9, 24 and 48 h after infection for the broad screening of fish immune and oxidative stress responses. Infected animals presented marked anaemia, neutrophilia and monocytosis, conditions that are correlated with an increased expression of genes related to inflammation and phagocytic activity. Similar studies with different fish species and bacteria can be useful for the definition of health biomarkers that might help fish farmers to prevent the occurrence of such diseases. 相似文献
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Mixture design applied for the development of films based on starch,polyvinyl alcohol,and glycerol 下载免费PDF全文
Juliano Zanela Juliana Bonametti Olivato Adriana Passos Dias Maria Victória Eiras Grossmann Fabio Yamashita 《应用聚合物科学杂志》2015,132(43)
Starch and polyvinyl alcohol (PVA) are biodegradable materials with potentiality to replace the conventional polymers in some applications. The aim of this work was to produce biodegradable films of PVA, cassava starch, and glycerol by thermoplastic extrusion using a mixture design to evaluate the effects of each component in the blend properties. Six formulations were prepared using a twin‐screw extruder coupled with a calender. All the materials were visually homogeneous and presented good processability. Mechanical properties were dependent on both the relative humidity conditioning and the formulation; higher relative humidities detracted the mechanical properties, which was associated to plasticizer effect of the water. Furthermore, the mechanical properties were better when higher concentrations of PVA were used, resulting in films with lower opacity, lower water vapor permeability, and higher thermal stability, according to TGA. Biodegradable materials based on starch, PVA, and glycerol have adequate mechanical and processing properties for commercial production. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42697. 相似文献