三种山茶属金花茶组植物花朵类黄酮成分研究

该研究以山茶属金花茶组的金花茶、凹脉金花茶和崇左金花茶为材料,利用超高效液相色谱-四极杆-飞行时间质谱联用技术定性定量分析其花朵中类黄酮成分与含量。结果表明:三种植物中检测到15种类黄酮,其中天竺葵素-3-O-葡萄糖苷、木犀草素、木犀草素-7-O-芸香糖苷、槲皮素-3,7-O-二葡萄糖苷、芸香柚皮苷、圣草素和染料木苷为金花茶组首次发现;槲皮素-3-O-葡萄糖苷、槲皮素-7-O-葡萄糖苷、槲皮素-3-O-芸香糖苷和山萘酚-3-O-葡萄糖苷为凹脉金花茶和崇左金花茶中首次发现。儿茶素、表儿茶素、槲皮素-3-O-葡萄糖苷、槲皮素-7-O-葡萄糖苷、槲皮素-3-O-芸香糖苷和山萘酚-3-O-葡萄糖苷为三个物种主体成分;天竺葵素-3-O-葡萄糖苷为金花茶特有,槲皮素-3,7-O-二葡萄糖苷为崇左金花茶特有;木犀草素-7-O-芸香糖苷主要存在于金花茶和崇左金花茶;木犀草素主要存在于凹脉金花茶和崇左金花茶。类黄酮类型主要为儿茶素类、槲皮素类、木犀草素类和山萘酚类;崇左金花茶中槲皮素类、木犀草素类及类黄酮总量远高于金花茶和凹脉金花茶,凹脉金花茶和崇左金花茶儿茶素类高于金花茶,金花茶和崇左金花茶山萘酚类高于凹脉金花茶。     

猪下丘脑发育差异表达基因的分离、克隆与表达

在小梅山猪下丘脑不同发育阶段,用mRNA差异显示技术分离并筛选出一个差异表达片段,命名为CQ01,221 bp.测序与BLAST分析发现,CQ01与猪血管内皮生长因子A(VEGFA)高度同源96%.半定量分析结果显示,CQ01在初情期时下丘脑中表达量较高.     

Interaction of climate and socio-ecological environment drives the dengue outbreak in epidemic region of China

Transmission of dengue virus is a complex process with interactions between virus, mosquitoes and humans, influenced by multiple factors simultaneously. Studies have examined the impact of climate or socio-ecological factors on dengue, or only analyzed the individual effects of each single factor on dengue transmission. However, little research has addressed the interactive effects by multiple factors on dengue incidence. This study uses the geographical detector method to investigate the interactive effect of climate and socio-ecological factors on dengue incidence from two perspectives: over a long-time series and during outbreak periods; and surmised on the possibility of dengue outbreaks in the future. Results suggest that the temperature plays a dominant role in the long-time series of dengue transmission, while socio-ecological factors have great explanatory power for dengue outbreaks. The interactive effect of any two factors is greater than the impact of single factor on dengue transmission, and the interactions of pairs of climate and socio-ecological factors have more significant impact on dengue. Increasing temperature and surge in travel could cause dengue outbreaks in the future. Based on these results, three recommendations are offered regarding the prevention of dengue outbreaks: mitigating the urban heat island effect, adjusting the time and frequency of vector control intervention, and providing targeted health education to travelers at the border points. This study hopes to provide meaningful clues and a scientific basis for policymakers regarding effective interventions against dengue transmission, even during outbreaks.     

广西五皇山地区植物区系特性

为揭示广西南部五皇山地区的植物区系特征，通过野外调查和文献查阅，对广西五皇山国家地质公园及邻近区域的植物资源进行调查研究。结果表明，五皇山地区分布野生植物1 002种，隶属于167科581属，包括蕨类植物20科37属73种, 裸子植物3科4属5种，被子植物144科540属924种，以被子植物占优势。科属的地理成分均以热带成分为主，属的热带性更强，其中泛热带成分占最大优势，温带成分则以北温带为主。中国特有属4属，未见中国特有科。该地区植物区系总体表现为物种丰富度高，区系热带性质强，特有性弱的特征。     

Dcaf11 activates Zscan4-mediated alternative telomere lengthening in early embryos and embryonic stem cells

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