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排序方式: 共有1071条查询结果,搜索用时 8 毫秒
1.
Ailing Jia Yuwen Shi Yuhang Zhang Yuanyuan Diao Baijin Chang Mengcheng Jiang Weipeng Liu Zhidong Qiu Chaomei Fu Ye Qiu 《化学与生物多样性》2023,20(4):e202200949
This study investigated the effect of butanol extract of AS (ASBUE) on atherosclerosis in apolipoprotein E-deficient (ApoE−/−) mice. The mice were administered ASBUE (390 or 130 mg/kg/day) or rosuvastatin (RSV) via oral gavage for eight weeks. In ApoE−/− mice, ASBUE suppressed the abnormal body weight gain and improved serum and liver biochemical indicators. ASBUE remarkably reduced the aortic plaque area, improved liver pathological conditions, and lipid metabolism abnormalities, and altered the intestinal microbiota structure in ApoE−/− mice. In the vascular tissue of ASBUE-treated mice, P-IKKβ, P-NFκB, and P-IκBα levels tended to decrease, while IκB-α increased in high fat-diet-fed atherosclerotic mice. These findings demonstrated the anti-atherosclerotic potential of ASBUE, which is mediated by the interaction between the gut microbiota and lipid metabolism and regulated via the Nuclear Factor-kappa B (NF-κB) pathway. This work paves the groundwork for subsequent studies to develop innovative drugs to treat atherosclerosis. 相似文献
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四川55种鱼生活史型的研究 总被引:1,自引:0,他引:1
四川55种鱼生活史型的研究刁晓明,罗一兵李波(西南农业大学水产系,重庆630716)(重庆大学计算机系,630000)LifeHistoryPatternsof55FishSpeciesinSichuan¥DiaoXiaoming;LuoYibing... 相似文献
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Photosynthesis-deficient mutant 45-3B of the green alga Chlamydomonas reinhardtii contains a chloroplast mutation that causes valine-331 to be replaced by alanine within the large subunit of ribulose-1,5-bisphosphate carboxylase/oxygenase. This amino acid substitution occurs in loop 6 of the alpha/beta-barrel active site, three residues distant from catalytic lysine-334. The mutation reduces the specific activity of the enzyme and also reduces its CO2/O2 specificity factor by 42%, but the amount of holoenzyme is unaffected. In a previous study, an intragenic-suppressor mutation, named S40-9D, was selected that causes threonine-342 to be replaced by isoleucine, thereby increasing the CO2/O2 specificity of the mutant enzyme by 36%. To determine which other residues might be able to complement the original mutation, nine additional genetically independent revertants have now been analyzed. Another intragenic suppressor, represented by mutation S61-2J, causes glycine-344 to be replaced by serine. This change increases the CO2/O2 specificity of the mutant enzyme by 25%. Of the revertants recovered and analyzed, the mutant enzyme was improved only due to true reversion or by intragenic suppression mediated by substitutions at residues 342 or 344. Changes in the physical properties of the two pairs of complementing substitutions indicate that steric effects within loop 6 are responsible for the observed changes in the CO2/O2 specificity of the enzyme. 相似文献
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新烟碱类化合物基于烟碱结构改造修饰制备,相较菊酯、含磷类等杀虫剂,因其选择性毒力被认为是一类对人类和生态无害的农药。然而,近年来由于新烟碱类杀虫剂(neonicotinoid insecticides)过度施用,其残余或转化的物质通过在土壤与水体中累积,影响昆虫甚至哺乳动物及其生理与行为,导致了一系列生态环境问题和继发危害。本文聚焦新烟碱类杀虫剂的产业现状,面向生物降解新烟碱类杀虫剂这一迫切需求,围绕新烟碱类杀虫剂的微生物菌株资源,重点阐述微生物降解新烟碱类杀虫剂的代谢机制及其多样性。通过梳理新烟碱类杀虫剂生物降解及其应用转化的关键问题和前沿进展,旨在为借助合成生物学和宏基因组学手段建立或筛选安全可控的新烟碱类杀虫剂的高效转化体系提供参考。 相似文献
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Guanqing Jia Xiaotong Liu James C. Schnable Zhengang Niu Chunfang Wang Yuhui Li Shujun Wang Suying Wang Jinrong Liu Erhu Guo Hui Zhi Xianmin Diao 《PloS one》2015,10(5)
Crop improvement is a multifaceted micro-evolutionary process, involving changes in breeding approaches, planting configurations and consumption preferences of human beings. Recent research has started to identify the specific genes or genomic regions correlate to improved agronomic traits, however, an apparent blank between the genetic structure of crop elite varieties and their improving histories in diverse modern breeding programs is still in existence. Foxtail millet (Setaria italica) was one of the earliest cereal crops to be domesticated and served as a staple crop for early civilizations in China, where it is still widely grown today. In the present trial, a panel of foxtail millet elite varieties, which were released in the last sixty years in different geographical regions of China, was characterized using microsatellite markers (SSRs). A clear separation of two subpopulations corresponding to the two eco-geographical regions of foxtail millet production in China was identified by the dataset, which also indicated that in more recently released elite varieties, large quantities of accessions have been transferred from spring-sowing to summer-sowing ecotypes, likely as a result of breeding response to planting configurations. An association mapping study was conducted to identify loci controlling traits of major agronomic interest. Furthermore, selective sweeps involved in improvement of foxtail millet were identified as multi-diverse minor effect loci controlling different agronomic traits during the long-term improvement of elite varieties. Our results highlight the effect of transition of planting configuration and breeding preference on genetic evolvement of crop species. 相似文献
10.
菲菊头蝠是分布于亚热带和热带的翼手目种类,在中国大陆南部和海南岛有广泛分布。为探讨热带菲菊头蝠是否具有冬眠期(12 月至翌年2 月)储精现象及生殖腺组织结构的变化,对海南岛的菲菊头蝠成年雄蝠和成年雌蝠生殖系统在冬眠期间的变化进行了石蜡切片观察。结果显示:成年雄蝠在冬眠期间附睾内储存大量精子,推测其储存时间超过2 个月;冬眠期间曲细精管横截面积、精子细胞数量和间质细胞数量在冬眠期逐月显著性减少,精原细胞和精母细胞的数量在12 月与翌年1 月间均无显著性变化,而在冬眠末期的2 月显著增多。在雌蝠子宫和卵巢内均未发现精子储存现象,但卵巢内具有初级卵泡和次级卵泡,雄蝠在冬眠期间曲细精管逐月萎缩,但生精上皮精母细胞的数量在冬眠末期明显上升。 相似文献