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901.
Aberrant expression of long noncoding RNAs (lncRNAs) contributes to all phenotypes of cancer including metastasis, which is a major cause of death in many advanced malignancies. One particular lncRNA, H19, is found to be a crucial player in cancer progression by modulating multiple microRNAs (miRNAs). In this study, we screened miRNAs possibly associated with H19 using lung carcinoma cell lines and patient with lung cancer tissues, and selected one possible hit, hsa-miR-6515-3p, to perform in vitro functional assays. Its inhibition leads to decreased proliferation and migration of SPC-A1 lung cancer cells and is in good correlation with H19-knockdown groups. These results indicate that H19 may be an epigenetic regulator of miR-6515-3p, and its dysregulation may contribute to lung cancer progression and metastasis.  相似文献   
902.
Since the start of the 20th century, many invasive alien species (IAS) have spread rapidly around the world, causing serious threats to economies, societies and the environment. Bactrocera dorsalis (Hendel) (Diptera: Tephritidae) is an important quarantine insect species in many countries that spread around the world over the last century. This review collected information on the distribution of B. dorsalis to explore the patterns of its invasion expansion. We found B. dorsalis to be distributed in 75 countries (comprised of 124 geographical distribution regions: provinces or states) in Asia, Africa, North America, South America and Oceania up to 2017. Asia and Africa were the most represented regions, accounting for 86.3% of the total number of countries. From 1910 to 1990, B. dorsalis was only found in five countries, but in the last three decades, it has experienced a sharp increase in its rate of spread, invading 70 more countries. Global temperature anomaly has significantly positive correlation with the spread of B. dorsalis. The results of this review provide a theoretical basis for understanding and predicting the continued spread of B. dorsalis under global changes.  相似文献   
903.
李峰  丁长青 《动物学杂志》2006,41(2):128-134
持久性有机污染物(POPs)是高残留物质,进入生物体后会长期存留并产生危害。近年来,有关生物体中POPs的研究已成为环境化学、生态毒理学研究的热点之一。本文概述了持久性有机污染物(POPs)的主要类型、生态特征、来源和污染效应。介绍了POPs在鸟类体内富集的特点及其对鸟类的危害;分析了以鸟类作为环境监测指示生物时应注意的问题;对POPs的防治以及利用鹭类等水鸟监测环境污染的方法提出了建议。  相似文献   
904.
徐峰  马鸣  吴逸群 《动物学杂志》2006,41(6):139-141
2005年10~12月,在新疆托木尔峰自然保护区用直接观察法对193头次北山羊(Capra ibex)的活动节律和时间分配进行了观察。结果表明,北山羊群冬季的活动规律性较强,呈现双峰型,2个高峰时段为08∶00~08∶30时和16∶30~17∶00时前后,活动频率分别为98.6%和93.3%。同时发现冬季其61%的活动时间用于采食,用于移动和站立的时间分别为19%和15%。这种活动节律可能与光照以及人类放牧干扰有关。  相似文献   
905.
采用响应面优化法对超声波辅助法同步提取川芎精油(LCEO)和多糖(LCP)工艺条件进行优化,以总还原力和DPPH·清除率为指标评价LCEO和LCP的抗氧化活性.结果表明,川芎精油和多糖提取的最佳工艺条件为:液料比16mL/g,超声时间17 min,提取时间4.3 h,在此条件下,精油提取率为1.35%,多糖提取率为2....  相似文献   
906.
Background Rhizoctonia solani is a pathogenic fungus that causes serious diseases in many crops, including rice, wheat, and soybeans. In crop production, it is very important to understand the pathogenicity of this fungus, which is still elusive. It might be helpful to comprehensively understand its genomic information using different genome annotation strategies.MethodsAiming to improve the genome annotation of R. solani, we performed a proteogenomic study based on the existing data. Based on our study, a total of 1060 newly identified genes, 36 revised genes, 139 single amino acid variants (SAAVs), 8 alternative splicing genes, and diverse post-translational modifications (PTMs) events were identified in R. solani AG3. Further functional annotation on these 1060 newly identified genes was performed through homology analysis with its 5 closest relative fungi.ResultsBased on this, 2 novel candidate pathogenic genes, which might be associated with pathogen-host interaction, were discovered. In addition, in order to increase the reliability and novelty of the newly identified genes in R. solani AG3, 1060 newly identified genes were compared with the newly published available R. solani genome sequences of AG1, AG2, AG4, AG5, AG6, and AG8. There are 490 homologous sequences. We combined the proteogenomic results with the genome alignment results and finally identified 570 novel genes in R. solani.ConclusionThese findings extended R. solani genome annotation and provided a wealth of resources for research on R. solani.  相似文献   
907.
马尾松Pinus massoniana当年生幼苗中会出现全初生叶和全次生针叶两种变异类型,它们的根系生长以及外生菌根(ectomycorrhiza,ECM)真菌群落是否也表现出差异,截止目前尚不明晰.本研究以马尾松全初生叶及全次生针叶幼苗类型为材料,采集幼苗根系,利用万深LA-S植物根系分析系统测定根系形态,采用TTC...  相似文献   
908.
The potential antimicrobial compound Chuangxinmycin (CXM) targets the tryptophanyl-tRNA synthetase (TrpRS) of both Gram-negative and Gram-positive bacteria. However, the specific steric recognition mode and interaction mechanism between CXM and TrpRS is unclear. Here, we studied this interaction using recombinant GsTrpRS from Geobacillus stearothermophilus by X-ray crystallography and molecular dynamics (MD) simulations. The crystal structure of the recombinant GsTrpRS in complex with CXM was experimentally determined to a resolution at 2.06 Å. After analysis using a complex-structure probe, MD simulations, and site-directed mutation verification through isothermal titration calorimetry, the interaction between CXM and GsTrpRS was determined to involve the key residues M129, D132, I133, and V141 of GsTrpRS. We further evaluated binding affinities between GsTrpRS WT/mutants and CXM; GsTrpRS was found to bind CXM through hydrogen bonds with D132 and hydrophobic interactions between the lipophilic tricyclic ring of CXM and M129, I133, and V141 in the substrate-binding pockets. This study elucidates the precise interaction mechanism between CXM and its target GsTrpRS at the molecular level and provides a theoretical foundation and guidance for the screening and rational design of more effective CXM analogs against both Gram-negative and Gram-positive bacteria.  相似文献   
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