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排序方式: 共有329条查询结果,搜索用时 15 毫秒
1.
从胡椒科植物山蒟中分得两个新木脂素类成分(Ia)和(Ⅱ),以及巴豆环氧素(Crorepoxide)(Ⅲ)和β-谷甾醇(Ⅳ)。经光谱分析及化学鉴定,(Ia)、(Ⅱ)为新结构,分别命名为山蒟素 B(hancinone)、山蒟素 C(hancinone C)。 相似文献
2.
色木槭的变异式样及其分类学 总被引:5,自引:1,他引:4
色木槭(Aeer mono Maxim.)是分布于亚洲东部的一个变异极大的种。本文报道了7个亚种:色木槭(原亚种)(subsp.mono);海岛色木槭(亚种)(subsp.marmoraturn(Nichols.)T.Z.Hsu);毛萼色木槭(亚种)(subsp.glabrum(Levl.et Vant.)T.Z.Hsu);里光色木槭(亚种)(subsp.trichobasis(Nakai)T.Z.Hsu);金沙色木槭(亚种)(subsp.tricuspis(Rehd.)T.Z.Hsu);弯翅色木槭(亚种)(subsp.incurvaturn(Fang et P.L.Chiu)T.Z.Hsu);粉绿色木槭(亚种)(subsp.glaucum(Koidz.)T.Z.Hsu),讨论了其变异式样和地理分布。 相似文献
3.
VIRGINIA SEYMOUR 《Plant, cell & environment》1985,8(9):631-638
Abstract The leaves of Berberis aquifolium (Pursh.) exhibit either diffuse or specular (shiny) reflection, depending on the variety, but in no case are the leaves obviously glaucous. The dull-surfaced leaves were less wettable than the glossy ones. Using scanning electron microscopy it was determined that the diffuse reflection was due to tubular crystals of wax 250 nm in diameter. The crystals were primarily composed of 19-nonacosanol, a 29-carbon secondary alcohol, as determined by gas chromatography-mass spectrometry. The chemical constituents of the wax underlying the tubes appeared to be the same as those of the wax from glossy leaves, with 29-carbon and 31-carbon n-alkanes and n-heptacosanol as major constituents. The reflection spectra of dull-surfaced (diffuse reflection) or glossy (specular reflection) leaves were the same, as were those of leaves with different amounts of epicuticular wax. Removing the epicuticular wax with chloroform did not change the spectrum. 相似文献
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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
6.
利用灵敏度高,专一性强的放射免疫法(RIA)测定了苦瓜和瓜萎不同器官中皮质醇的含量。结果表明:苦瓜和瓜萎各器官均含有皮质醇,且含量在50~450ng/g.FW;顶芽中含量最高,其次是花器官;苦瓜和瓜篓雌花皮质醇含量明显高于雄花,且雌花在授粉后当天含量最高,说明皮质醇可能在植物的生长发育过程中起某种作用。 相似文献
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采用石蜡切片方法对粉叶小檗(Berberis pruinosa Franch.)的大孢子发生和雌配子体形成过程进行了研究。主要结果如下:雌蕊1枚,子房单心皮,边缘胎座,2枚胚珠倒生,具双珠被,厚珠心,珠孔由内外两层珠被共同形成,呈“Z”字形;单孢原,位于珠心表皮下;直线形大孢子四分体,合点端的1个大孢子发育为功能大孢子,胚囊发育类型为蓼型;成熟胚囊中,2个极核在受精前融合为次生核;3个反足细胞不发达,较早退化;"品"字形卵器,其中助细胞发达且具丝状器。 相似文献
9.
Takashi Fujita Hitoshi Hatamoto Mari Miyamoto Taisuke Iwasaki Shin-ichi Takafuji 《Biotechnology letters》1998,20(11):1057-1061
Cell suspensions derived from Acer nikoense callus, not containing (S)-rhododendrol, converted 4-(p-hydroxyphenyl)-2- butanone into (R)-, (S)-rhododendrol and their glycosides. (R)- and (S)-rhododendrol formed was only detected in the culture medium and their glycosides only in the cells. The former compound disappeared within a short time and the latter one also tended to decrease during prolonged culture. Quantitative analysis of rhododendrol glycosides in the callus showed that most of them were (S)-rhododendrol 2-O--D-glucopyranoside and its content was much lower than that of the original plants. © Rapid Science Ltd. 1998 相似文献
10.
不同理化因子对雪莲培养细胞中黄酮类形成的影响 总被引:26,自引:2,他引:24
研究了不同理化因子对水母雪莲(Saussurea medusa Maxim)愈伤组织生长及黄酮类化合物生物合成的影响。结果表明,有利于细胞生长及黄酮形成的合适温度为25℃。白光对愈伤组织生长无促进作用,但有利于黄酮的形成。培养基中添加1mg/L NAA和O.2mg/L的KT组合对细胞的生长较有促进作用。5%蔗糖和1%葡萄糖的组合有利于细胞的生长和黄酮的形成。用60C0-γ射线辐照愈伤组织,在剂量为4000Gy的条件下,获得一个合成黄酮能力高于原愈伤组织70%的细胞系。用高效液相和紫外分光光度法,测定离体培养光照条件下干细胞总黄酮的含量为3.2%,是暗培养的4.4倍。培养温度25℃时干细胞黄酮的含量为2.02%,分别为20℃,35℃时的5倍和3.2倍。 相似文献