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1.
Eucalyptus leaves contain a high proportion of essential oils comprising of a complex mixture of monoterpenes such as 1,8-cineole, alpha-pinene, d-limonene and p-cymene. In this study, hepatic levels of microsomal lauric acid hydroxylase and peroxisomal cyanide-intensive palmitoyl coenzyme A oxidative activities were examined in livers of possums given an artificial diet consisting of the above monoterpenes for 10 days. These values were compared with those of possums fed a control diet containing only fruits and cereals. Peroxisomal cyanide-intensive palmitoyl coenzyme A oxidative activity was significantly higher in livers of treated possums relative to that of control possums (2.96+/-0.93 vs. 0.98+/-0.88 nmol/mg protein per min, P<0.01) (mean+/-S.D., n=4). A small increase in microsomal lauric acid hydroxylase activity was observed in the treated possum in comparison with the control group (4.40+/-0.85 vs. 3.60+/-0.48 nmol/mg protein per min) (mean+/-S.D., n=4). A higher NAD/ NADP ratio was observed in treated possums as compared with control possums (4.73+/-0.65 vs. 3.51+/-0.64 nmol/mg protein per min, P<0.05) (mean+/-S.D., n=4). No other statistically significant differences in pyridine nucleotide contents were found between control and treated possums. Northern blot analysis of mRNA from rat, human, terpene treated and control possum livers, using the corresponding koala cDNA probes, detected a more intense acyl CoA oxidase (AOX) mRNA band in livers of terpene fed possums. Negligible differences in the intensity of CYP4A and PPARalpha mRNA bands were observed between the two groups. These data suggest that Eucalyptus terpenes elevate hepatic AOX expression in possums.  相似文献   
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Cytochromes P450 (CYPs) are critically important in the oxidative metabolism of a diverse array of xenobiotics and endogenous substrates. We have previously reported the cloning and characterisation of the koala CYP4A15, the first reported member of the CYP4 family from marsupials, and have demonstrated important species differences in CYP4A activity and tissue expression. In the present study, the cloning of CYP4B1 in the wallaby (Macropus eugenii) and their expression across marsupials is described. Rabbit anti-mouse CYP4B1 antibody detected immunoreactive proteins in lung and liver microsomes from all test marsupials, with relative weak signal detected from the koala, suggesting a species-specific expression. Microsomal 2-aminofluorene bio-activation (a CYP4B1 marker) in wallaby lung was comparable to that of rabbit, with significant higher activities detected in wallaby liver and kidneys compared to rabbit. A 1548 bp wallaby lung CYP4B complete cDNA, designated CYP4B1, which encodes a protein of 510 amino acids and shares 72% nucleotide and 69% amino acid sequence identity to human CYP4B1, was cloned by polymerase chain reaction approaches. The results demonstrate the presence of wallaby CYP4B1 that shares several common features with other published CYP4Bs; however the wallaby CYP4B1 cDNA contains four extra amino acid residues at the NH2-terminal, a fundamentally conserved transmembrane anchor of all eukaryote CYPs.  相似文献   
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Journal of Plant Growth Regulation - The primary factors that determine the longevity of cut roses are variable and depend on a cultivar’s sensitivity to ethylene. The vase life of...  相似文献   
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The development of polychromatic cytometry has contributed to significant progress in the field of human immunology. Although numerous functional studies of rare cell populations have been performed using this technology, here we used polychromatic cytometry to explore the dynamics of complex cellular systems implicated in innate immunity. We used PBMC stimulated with live influenza virus as an experimental model. We studied the time course of activation of PBMC, which contain DC, monocytes, and NK cells, all of which are, in addition to their innate immune properties, susceptible to Flu infection. We developed 12 color panels to investigate intracellular expression of IFN-α, TNF-α, IL-12, IL-6, IFN-γ, CD107, and influenza virus nucleoprotein simultaneously in these cell populations. These panels allowed reproducible determination of activation markers induced in DC after their direct exposure to various stimulations or in NK cells by indirect DC-mediated activation within the complex cellular environment. The ability to use a low number of cells and reduced quantities of reagents permitted us to perform kinetic experiments. The power of polychromatic cytometry associated with bioinformatic tools allowed us to analyze the multiple functional data generated as dynamic clustering maps. These maps present a readily understandable view of activation events induced in different populations of PBMC. In addition, it reveals new information on the coordination of the complex pathways induced and on the cellular interactions that sustained indirect DC-mediated NK cell activation. Our work shows that polychromatic cytometry is a tool for discoveries in unexplored complex cell systems, at the crossroads of immunology and virology. ? 2012 International Society for Advancement of Cytometry.  相似文献   
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Key message

Novel barley (1 → 3, 1 → 4)-β-glucan endohydrolases with increased thermostability.

Abstract

Rapid and reliable degradation of (1 → 3, 1 → 4)-β-glucan to produce low viscosity wort is an essential requirement for malting barley. The (1 → 3, 1 → 4)-β-glucan endohyrolases are responsible for the primary hydrolysis of cell wall β-glucan. The variation in β-glucanase genes HvGlb1 and HvGlb2 that encode EI and EII, respectively, were examined in elite and exotic germplasm. Six EI and 14 EII allozymes were identified, and significant variation was found in β-glucanase from Hordeum vulgare ssp. spontaneum (wild barley), the progenitor of modern cultivated barley. Allozymes were examined using prediction methods; the change in Gibbs free energy of the identified amino acid substitutions to predict changes in enzyme stability and homology modelling to examine the structure of the novel allozymes using the existing solved EII structure. Two EI and four EII allozymes in wild barley accessions were predicted to have improved barley β-glucanase thermostability. One novel EII candidate was identified in existing backcross lines with contrasting HvGlb2 alleles from wild barley and cv Flagship. The contrasting alleles in selected near isogenic lines were examined in β-glucanase thermostability analyses. The EII from wild barley exhibited a significant increase in β-glucanase thermostability conferred by the novel HvGlb2 allele. Increased β-glucanase thermostability is heritable and candidates identified in wild barley could improve malting and brewing quality in new varieties.
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Quantitative trait loci (QTLs) associated with grain weight, grain width, kernel hardness and malting quality were mapped in a doubled haploid population derived from two elite Australian malting barley varieties, Navigator and Admiral. A total of 30 QTLs for grain weight, grain width and kernel hardness were identified in three environments, and 63 QTLs were identified for ten malting quality traits in two environments. Three malting quality traits, namely β-amylase, diastatic power and apparent attenuation limit, were mainly controlled by a QTL linked to the Bmy1 gene at the distal end of chromosome 4H encoding a β-amylase enzyme. Six other malting quality traits, namely α-amylase, soluble protein, Kolbach index, free amino-acid nitrogen, wort β-glucan and viscosity, had coincident QTL clustered on chromosomes 1HS, 4HS, 7HS and 7HL, which demonstrated the interdependence of these traits. There was a strong association between these malt quality QTL clusters on chromosomes 1HS and 7HL and the major QTL for kernel hardness, suggesting that the use of this trait to enable early selection for malting quality in breeding programs would be feasible. In contrast, the majority of QTLs for hot-water extract were not coincident with those identified for other malt quality traits, which suggested differences in the mechanism controlling this trait. Novel QTLs have been identified for kernel hardness on chromosomes 2HL and 7HL, hot-water extract on 7HL and wort β-glucan on 6HL, and the resulting markers may be useful for marker-assisted selection in breeding programs.  相似文献   
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A new iridoid, 5β,6β-dihydroxyantirrhide (1) was isolated from the dried leaves of Pseuderanthemum carruthersii (Seem.) Guill. var. atropurpureum (Bull.) Fosb. (Acanthaceae), together with 13 known compounds, including two iridoids, linarioside and antirrhinoside; five phenylethanoids, echipuroside A, verbascoside, isoverbascoside, isomartynoside and osmanthuside B; and six flavonoids, luteolin 7-O-β-d-glucopyranoside, luteolin 7-O-rutinoside, apigenin 7-O-rutinoside, apigenin 6-C-α-l-arabinopyranosyl–8-C-β-l-arabinopyranoside, apigenin 6,8-di-C-α-l-arabinopyranoside and apigenin 6-C-β-d-xylopyranosyl–8-C-α-l-arabinopyranoside. Their chemical structures were elucidated by 1D and 2D NMR as well as HR-ESI-MS spectroscopic analysis. Some purified compounds were evaluated the acetylcholinesterase inhibition and cytotoxic activities against the HeLa cervical cancer cell line and the MCF-7 breast cancer cell line at the concentration of 100 μg/mL. Luteolin 7-O-β-d-glucopyranoside exhibited cytotoxic activities against both the HeLa cervical cancer cell line and the MCF-7 breast cancer cell line. Verbascoside and isoverbascoside showed strong cytotoxic activity against the MCF-7 breast cancer cell line. The tested compounds showed the AChE inhibitory activity fairly weak.  相似文献   
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