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991.
In seeds and leaves of oats (Avena sativa L.) 12 different sterols (cholesterol, cholstanol, 7-cholestenol, campesterol, campestanol, stigmasterol, lophenol, sitosterol, stigmastanol, 5-avenasterol, 7-avenasterol and 7-stigmastenol) have been identified. The sterol pattern is qualitatively the same, but the relative composition is different in leaves and in seeds. Leaves contain mainly sitosterol, stigmasterol, cholesterol and campesterol, but only minor portions of avenasterols. Seeds contain sitosterol, 5- and 7-avenasterol, campesterol, but only minor amounts of stigmasterol and cholesterol. In leaf lipids 1-hexacosanol (2.35 wt % of total lipid) has also been identified. 相似文献
992.
本文报道裂胸螨科中国1新记录属:似虫穴螨属ZerconopsisHul,1918,并记述2新种:黑龙江似虫穴螨Z.heilongjiangensis,sp.nov.和伊春似虫穴螨Z.yichunensis,sp.nov.。 相似文献
993.
Temporal and spatial variations of shoot structural parameters, including shoot silhouette to projected needle area ratio, are very important, e.g., for the correction of leaf area index estimated by indirect methods. Here we bring few examples of their evolution within mountain spruce monoculture planted in two different densities. 相似文献
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Rafael D. Marchi Carolina Mathias Gabriel A. K. Reiter Rubens Silveira de Lima Flvia Kuroda Cícero de Andrade Urban Ricardo. L. R. de Souza Daniela F. Gradia Enilze M. S. F. Ribeiro Iglenir J. Cavalli Jaqueline Carvalho de Oliveira 《Genetics and molecular biology》2021,44(1)
Breast cancer (BC) is the leading cause of death by this disease in women worldwide. Among the factors involved in tumorigenesis, long non-coding RNAs (lncRNAs) and their differential expression have been associated. Differences in gene expression may be triggered by variations in DNA sequence, including single nucleotide polymorphisms (SNPs). In the present study, we analyzed the rs527616 (C>G), located in the lncRNA AQP4-AS1, using PCR-SSP in 306 BC patients and 312 controls, from a Brazilian population. In the BC group, the frequency found for CG heterozygotes was above the expected and the overdominant model is the best one to explain our results (OR: 1.70, IC 95%: 1.23-2.34, P<0.001). Furthermore, the SNP were associated with age at BC diagnosis and the risk genotype more frequent in the older age group. According to TCGA data, AQP4-AS1 is down-regulated in BC tissue, and the overexpression is associated with better prognoses, including Luminal A, HER2-, stage 1 of disease and smaller tumor. In conclusion, the CG genotype is associated with increased susceptibility in the southern Brazilian population. This SNP is mapped in the lncRNA AQP4-AS1, showing differential expression in BC samples. Based on these results, we emphasize the potential of the role of AQP4-AS1 in cancer. 相似文献
997.
Envelope protein-mediated down-regulation of hepatitis B virus receptor in infected hepatocytes 总被引:2,自引:0,他引:2 下载免费PDF全文
Entry of duck hepatitis B virus (DHBV) is initiated by specific interaction of its large envelope protein (L) with a cellular entry receptor, recently identified as carboxypeptidase D (CPD; historically gp180). In this report, we present evidence demonstrating that this receptor is down-regulated as a result of DHBV infection: (i) receptor levels determined by Western blot were much reduced in DHBV-infected duck livers and undetectable by immunostaining in infected cultured hepatocytes; (ii) results from metabolic labeling experiments indicate enhanced receptor protein turnover; (iii) the kinetics of receptor loss from newly infected cells correlated with the accumulation of newly synthesized viral protein; (iv) expression of DHBV L protein, transduced from a recombinant adenovirus, was sufficient to eliminate gp180/CPD from the Golgi compartment, its normal predominant location; (v) gp180/CPD remained absent from the Golgi compartment in infected hepatocytes, even after overexpression from a recombinant adenovirus, while residual amounts subsequently became detectable in a perinuclear compartment, containing DHBV L protein; (vi) expression of DHBV L protein in a HepG2 cell line, stably expressing gp180/CPD, leads to incomplete receptor maturation and induces its degradation. Taken together, these data are consistent with a model in which the virus receptor interacts early in the biosynthetic pathway with the viral L protein, leading to its retention in a pre-Golgi compartment and to subsequent degradation, thus preventing receptor interference with the export of DHBV via the secretory pathway which it shares with its receptor. Accordingly, and analogously with receptor down-regulation in retroviral systems, DHBV receptor down-modulation may account for the much-reduced efficiency of DHBV superinfection of preinfected hepatocytes. 相似文献
998.
Deficiency in the α1 subunit of Na+/K+‐ATPase Enhances the Anti‐Proliferative Effect of High Osmolality in Nucleus Pulposus Intervertebral Disc Cells 下载免费PDF全文
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The interaction between protonated dopamine and neutral RNA and DNA nucleosides was studied by means of density functional theory calculations in vacuum and in implicit water. On the most stable complexes formed with each of the nucleosides, the vertical absorption excitation energies were evaluated and compared with the values of separated dopamine and corresponding nucleoside. The most stable complex was formed with guanosine and the spectral changes in this complex resulted in a significant reduction of the oscillator strength of the first dopamine’s transition. In the first guanosine’s transition, a redshift of 0.2 eV was found combined with a reduction of the oscillator strength. 相似文献