992 resultados para 336-U1383B


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本论文由三章组成。第一章为综述,概述了植物中环烯醚萜类化合物的研究进展;第二和第三章为实验论文,分别报道了唇形科药用植物绵参和蔷薇科药用植物地榆的化学成分研究。 第一章概述了植物中环烯醚萜类化合物的研究成果,主要包括结构类型及药理活性等方面。 第二章包括两个部分。第一部分报道了藏药绵参(Eriophyton wallichii Benth)地上部分甲醇提取物的化学成分。采用正、反相硅胶柱层析等各种分离方法,从中共分离出7个化合物,有6个化合物为首次从该植物中分离得到,分别为β-谷甾醇(1),夏至草苦素(marrubiin,2),乌苏酸(3),cimigoside(4),5-deoxyantirrhinoside(5),8-表马钱子酸葡萄糖苷(8-epiloganic acid,6)和apigenin 7-(6''-p-coumaroyl)glucoside(7)。第二部分,采用高效液相色谱-质谱联用技术对绵参地上部分的甲醇提取物进行了分析,通过标准品对照紫、外光谱分析以及多级质谱分析与文献对照鉴定了8个成分,分别是:8-epiloganic acid(Ⅰ),quercitrin 3-glucoside-7-(6''-p-coumaroyl)glucoside(Ⅱ),ajugoside(I) (Ⅲ),chrysoeriol 7-O-E-p-coumaroyl-3-O-b-D-glucoside(Ⅳ),helichrysoside(Ⅴ),生物碱(Ⅵ),apigenin 2,3-dihydrogen-7-(6''-p-coumaroyl) glucoside(Ⅶ),apigenin 7-(6''-p-coumaroyl) glucoside(Ⅷ)。 第三章报道了中药地榆根部乙醇提取物正丁醇相的化学成分,通过正、反相硅胶柱层析等各种分离方法,从中分离得到8个化合物,分别为3,4¢- O-二甲基逆没食子酸(8),3,3¢,4¢-O-三甲基逆没食子酸(9)和3,4¢-O-二甲基逆没食子酸-4-O-b-D-木糖苷(10),19a-羟基-3-O-(a-L-阿拉伯糖)乌苏酸-28-O-b-D-葡萄糖苷(11), 3b-[(a-L-arabinopyranosyl)oxy]-urs-11,13(18)-dien-28-oic acid b-D- glucopyranosyl ester(13),3-O-a-L-arabinopyranosyl-urs-12,18(19)-dien-28-oic acid b-D-glucopyranosyl ester(14),儿茶素(15),还有一种可能是皂苷11的工作产物(12)。 This dissertation consisted of three chapters. The first chapter elaborated the progress of iridoids occurring in plants. The later two chapters respectively elaborated the chemical constituents of Eriophyton wallichii Benth. and Sanguisorba officinalis L. The first chapter is a review of the research progress of iridoids occurring in plants, which includes their structure and pharmacology. The second chapter consisted of two parts. The first part is about the chemical constituents of methanol extraction from the aerial parts of Eriophyton wallichii Benth. Seven compounds were isolated and identified. Among them, the compounds of marrubiin, ursolic acid, cimigoside, 5-deoxyantirrhinoside, 8-epiloganic acid,apigenin 7-(6''-p-coumaroyl)glucoside were firstly reported in this plant. A HPLC-MSn method was developed for rapid identification of major compounds of Eriophyton wallichii. A total of 8 peaks in the chromatograms were unequivocally determined (peaks 1, 8) or tentatively identified (peaks 2-7) based on the detailed UV and tandem mass spectra analysis. Seven components were identified as 8-epiloganic acid(Ⅰ),Quercitrin 3-glucoside-7-(6''-p-coumaroyl)glucoside(Ⅱ),ajugoside(I)(Ⅲ),Chrysoeriol 7-O-E-p-coumaroyl-3-O-b-D-glucoside(Ⅳ),helichrysoside(Ⅴ),apigenin 2,3-dihydrogen-7-(6''-p-coumaroyl) glucoside(Ⅵ),apigenin 7-(6''-p-coumaroyl) glucoside(Ⅶ)。 The third chapter elaborated the chemical constituents of methanol extraction from Sanguisorba officinalis L, eight compounds were isolated from this plant by repeat column chromatography over silica gel. These compounds were identified as 3,4′-O-dimethylellagic acid, 3,3′,4′-O-trimethylellagic acid, 3,4′-O-dimethylellagic acid-4-O-b-D-xyloside, 3b-O-a-L-arabinopyranosyl-19a- hydroxyl-urs-12-en-28-oic acid 28-b-D-glucopyranoside, 3b-[(a-L-arabinopyranosyl)oxy]-urs-11,13(18)-dien- 28-oic acid b-D-glucopyranosyl ester,3-O-a-L–arabinopyranosyl-urs-12,18(19) -dien-28-oic acid b-D-glucopyranosyl ester, catechin.

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本试验利用电子辐照PVA/CMC共混水凝胶,通过外观透明度、凝胶分数、溶胀度和红外光谱分析,研究了样品中结构的变化与外观透明度、凝胶分数和溶胀度的关系,以及辐照剂量对样品中结构和性能的影响。结果表明,不同比例的PVA与相同比例的CMC组成的共混水凝胶,经电子辐照后呈现不同的宏观特性。辐照样品萃取后得到的凝胶比萃取前的混合凝胶拥有更强的吸水性,表明辐照PVA/CMC共混凝胶形成了网状结构凝胶。几种竞争反应导致不同辐照剂量下混合凝胶中凝胶含量随PVA含量的变化变得复杂。辐照后样品的红外光谱分析显示,辐照使凝胶中部分仲醇中C上链接的H原子被取代而转变为叔醇,从而产生交联。

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目的检测经相同剂量不同剂量率X射线照射的BalB/C小鼠外周血淋巴细胞周期及胸腺和脾脏指数。方法18只BalB/c小鼠随机分为对照组(control),低剂量率照射组(20cGy/min)和高剂量率照射组(300cGy/min),每组6只。低剂量组和高剂量组采用剂量率分别为20cGy/min和300cGy/min的1GyX射线对小鼠进行全身照射,24h后取血及器官,用流式细胞仪检测外周血淋巴细胞的周期变化,用称量的方法得到胸腺和脾脏指数。结果高剂量率辐射时,小鼠外周血淋巴细胞的损伤较低剂量时大,而且对雄性鼠的影响大于雌性;同时,胸腺和脾脏指数变化也随着剂量率的增大而减小。结论低剂量率的照射对小鼠外周血淋巴细胞、胸腺和脾脏的影响较高剂量率辐射小;雌性鼠的辐射耐受能力较雄性强。

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简单地介绍了重丰中子远离核研究的科学意义,报告了重丰中子新核素的产生、分离和鉴别方法。