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91.
From the rhizomes of Smilax corbularia Kunth. (Smilacaceae), 11 compounds, (2R,3R)-2″-acetyl astilbin, (2R,3R)-3″-acetyl astilbin, (2R,3R)-4″-acetyl astilbin, (2R,3R)-3″-acetyl engeletin, (2R,3S)-4″-acetyl isoastilbin, 2-(4-hydroxyphenyl)-3,4,9,10-tetrahydro-3,5-dihydroxy-10-(3,4-dihydroxyphenyl)-(2R,3R,10R)-2H,8H-benzo [1,2-b:3,4-b′] dipyran-8-one, 2-(4-hydroxyphenyl)-3,4,9,10-tetrahydro-3,5-dihydroxy-10-(3,4-dihydroxyphenyl)-(2R,3R,10S)-2H, 8H-benzo [1,2-b:3,4-b′] dipyran-8-one, 3,4-dihydro-7-hydroxy-4-(3,4-dihydroxyphenyl)-5-[(1E)-2-(4-hydroxyphenyl) ethenyl]-2H-1-benzopyran-2-one, 3,4-dihydro-7-hydroxy-4-(3,4-dihydroxy-phenyl)-5-[(1E)-2-(3,4-dihydroxyphenyl) ethenyl]-2H-1-benzopyran-2-one, 3,4-dihydro-7-hydroxy-4-(4-hydroxy-3-methoxyphenyl)-5-[(1E)-2-(4-hydroxyphenyl) ethenyl]-2H-1-benzopyran-2-one, and 5,7,3′,4′-tetrahydroxy-3-phenylcoumarin along with 34 known compounds were isolated and characterized as 19 flavonoids, 14 catechin derivatives, 6 stilbene derivatives, and 6 miscellaneous substances. All isolates had their estrogenic and anti-estrogenic activities determined using the estrogen-responsive human breast cancer cell lines MCF-7 and T47D. The major constituents were recognized as flavanonol rhamnosides by the suppressive effect on estradiol induced cell proliferation at a concentration of 1 μM. Meanwhile, flavanonol rhamnoside acetates demonstrated estrogenic activity in both MCF-7 and T47D cells at a concentration of 100 μM, and they enhanced the effects of co-treated E2 on T47D cell proliferation at concentrations of more than 0.1 μM.  相似文献   
92.
目的:观察姜半夏乙醇提取物对人胃癌SGC7901细胞增殖和凋亡的影响。方法:不同浓度姜半夏乙醇提取物(终浓度为1mg/ml,0.5mg/ml,0.25mg/ml,0.125mg/ml)处理SGC7901细胞后,倒置相差显微镜下观察细胞的形态学变化;通过甲基噻唑基四唑法检测细胞增殖状况、描绘生长曲线,使用紫外分光光度法观察药物干预后细胞ATP酶活力;AnnexinV.异硫氰酸荧光素(fluorescein isothiocyanate,FITC)/碘化丙啶(propidium iodide,PI)双标记法流式细胞术检测姜半夏乙醇提取物对SGC7901细胞诱导凋亡的情况。结果:不同浓度姜半夏乙醇提取物均能不同程度地抑制人胃癌SGC7901细胞的增殖;在姜半夏乙醇提取物诱导细胞后细胞发生了边缘毛刺、体积缩小等形态学变化,同时可见细胞折光度和贴壁能力下降;Annexin V-F/TC/PI双标记法检测显示姜半夏乙醇提取物可诱导细胞发生凋亡;细胞总ATP酶活力在药物干预72小时后出现明显下降;并且随着药物浓度增加细胞凋亡率、细胞形态异常改变以及ATP酶活力抑制作用均呈上升趋势。结论:姜半夏乙醇提取物可抑制人胃癌SGC7901细胞的增殖,促进其凋亡,抑制细胞ATP酶活力。  相似文献   
93.
Vascular cambium ofBotrychium ternatum rhizome varied according to age, position and season was studied by light and electron microscopy. Cambium at the 6th internode (6-year-old cambium) had the greatest number of active cambial cells in August and September, thus it was in the most active stage. The active cells were characterized by the presence of a large vacuole, few storage materials such as starch grains within plastids or lipid droplets, a thin tangential wall; and various cell organelles in the thin peripheral layer of cytoplasm. When the 6-year-old cambium reached its dormant season after November, the dormant cells were filled with numerous storage materials and had few cell organelles. Our observations suggested that the initiation and cessation of cambial activity may be correlated with the annual life cycle of this plant: the vegetative and reproductive leaves began to emerge in June and July, respectively, and the sporophyll withered in November after the spore dispersal. Most cambial cells at the 10th internode, which remained in a dormant state throughout the year, were filled with numerous storage materials. Our results indicated that the activity of vascular cambium in the 10th internode was determinate.  相似文献   
94.
To analyse the potential reaction to firegenerated heat pulses, seeds of 12 species of plants and rhizomes of three species were exposed to elevated temperatures for 10 min. The tested material split into three groups with respect to heat tolerance: (1) the rhizomes, for which the lethal temperatures were in the range 55–59° C; (2) the seeds of most of the species tested, for which the lethal temperatures were in the range 65–75° C; (3) The seeds of two species of Leguminosae and three species of Geranium for which the lethal temperatures were around 100° C. For all three Geranium species and for one of the legume species, Anthyllis vulneraria, exposure temperatures above ca. 45° C resulted in dormancy release, and maximum germination occurred above 60–65° C. Speed of germination was little affected for most species, except after exposure to nearlethal temperatures, where it slowed down dramatically, although the seedlings emerging were healthy. We conclude that due to sharp temperature gradients in the soil during fire, differences in heat tolerance between species in most cases are not large enough to be a decisive factor in their post-fire colonising success. There are exceptions: the seeds of certain taxa that are impermeable to water in the dormant state, some of which have heat triggered germination.  相似文献   
95.
The morphological and anatomical responses to different depths of burial were examined in Rumex alpinus (Polygonaceae), a perennial plant with monopodial, horizontally growing rhizome. Its segments, which consist of 12–20 internodes, 1 to 2 mm in length each, are products of single growing seasons. The rhizomes regenerated from 5, 10 and 20 cm, but failed to emerge from 30 cm. Number of internodes produced during a growing season was not affected by burial but the length of internodes increased up to about 30-fold. The rhizomes growing up to the surface were subsidized by older rhizome segments. In the case of deeply buried rhizomes the carbohydrate reserves of the last-year-segment were nearly completely depleted. Evolutionary significance of the regeneration capacity is discussed.  相似文献   
96.
松嫩平原赖草无性系生长及其构件的年龄结构   总被引:10,自引:3,他引:7  
杨允菲  张宝田 《应用生态学报》2004,15(11):2109-2112
赖草是长根茎型禾草,是典型的无性系植物.在松嫩平原栽培条件下,移植第1年的赖草无性系,经过一个完整生长季的营养繁殖,最多可形成215个分蘖株,在4个取样的无性系中,最大的无性系是最小的5.4倍;经过2个完整生长季最多可形成2852个分蘖株,最大为最小的2.7倍.在无性系整体水平上,2个年度间无性系扩展面积平均增长了13.2倍,分蘖株平均增长了13.3倍,根茎的累积长度平均增长了15.9倍,根茎节数平均增长了11.2倍,根茎生物量平均增长了14.7倍.无性系分蘖株由2个龄级组成,呈增长型年龄结构,并且随着无性系的生长,其增长型年龄结构更为明显.无性系的芽库均由3个龄级组成,亦呈增长型年龄结构,但随着无性系的生长,其增长型年龄结构趋于减缓.赖草无性系以形成大量的根茎顶端芽和根茎节间芽发育成分蘖株,实现无性系空间生态位的扩展和持续更新.  相似文献   
97.
福建泽泻元素分析及其属性判别研究   总被引:3,自引:0,他引:3  
利用电感耦合等离子体质谱(ICP-MS),对福建建瓯产大叶、小叶泽泻中17种元素的含量进行了测定,在此基础上,运用SAS软件的DISCRIM过程对两类泽泻样品进行了判别分析,取得了良好的分类判别结果,利用上述方法得到的泽泻元素含量分布图谱有可能为中药材指纹图谱的建立及其规范化种植提供新的途径。  相似文献   
98.
用从野生建兰部分离的菌根真菌P15菌株感染墨兰Cymbidium sinense和建兰Cymbidium ensifolium的根状茎后,使寄主的呼吸速率、细胞色素C氧化酶、过氧化物酶活性明显增高,而感染前后IAA氧化酶活性变化不明显。两个品种相比较,建兰根状茎的呼吸速率、细胞色素C氧化酶和过氧化物酶活性均比墨兰的高,但墨兰的根状茎IAA氧化酶活性则高于建兰。  相似文献   
99.
100.
藕莲是莲(Nelumbo nucifera Gaertn.ssp.nucifera)的3种类型之一,在我国作为水生蔬菜栽培的历史愈两千年。对国家种质资源圃中来自17个省和直辖市的68份藕莲资源的19个形态和农艺性状进行了观察,并对其遗传变异进行了分析。结果发现整藕重与主藕重、主藕长和第三节粗成极显著正相关。通径分析结果表明主藕重对整藕重的正向效应最高(0.982)。主成分分析结果显示前4个成分占总变异的77.33%。结果还显示对整藕重负效应最高的是主藕重/整藕重(-0.296)。聚类分析发现所有藕莲资源可分为5组。  相似文献   
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