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活性筛选中发现尼泊尔水东哥 (Saurauia napaulensis DC.) 树皮95%乙醇提取物具有α-淀粉酶抑制活性、水麻(Debregeasia orientalis) 枝叶95%乙醇提取物显示血管紧张素转化酶(ACE)抑制活性、青荚叶(Helwingia japonica (Thunb.) Dieter.) 95%乙醇提取物的中小极性部分显示蛋白酪氨酸磷酸酯酶(PTP)1B抑制活性。为全面了解它们的成分及相关活性成份,主要运用硅胶柱层析方法从这三个植物分离得到39个化合物,通过波谱分析或与已知品对照的方法对其进行了鉴定。对木姜冬青(Ilex litseaefolia Hu et Tang)的成分做了进一步的研究,取得了如下结果。 1. 从尼泊尔水东哥树皮的95%乙醇提取物分离并鉴定12个化合物: auranamide、aurantiamide benzoate、齐墩果酸、β-谷甾醇、β-胡萝卜甙、乌苏酸、2α,3α-二羟基-12-烯-28-乌苏酸、2α,3β,24-三羟基-12-烯-28-乌苏酸、(2S,3S,4R,10E)-2-[(2'R)-2' -hydroxytetracosanoylamino] -10-octadecene -1,3,4-triol、 2α,3α,24-三羟基-12-烯-28-齐墩果酸、2α,3β-二羟基-12-烯-28-乌苏酸和2α,3α,24-三羟基-12-烯-28-乌苏酸。 2. 从水麻枝叶的95%乙醇提取物分离并鉴定了18个化合物:棕榈酸、二十烷酸、二十烷酸甲酯、β-谷甾醇、Monogynol A、桦木酸、Hederagenin、β-胡萝卜甙、18αH-19(29)-烯-3-酮-乌苏烷、3,4-开环-20(30)-烯-乌苏烷-3-酸、Pomolic acid,表儿茶素、儿茶素、槲皮素、槲皮素-3-O-β-D-吡喃葡萄糖苷、紫丁香苷、紫丁香酚苷和山萘酚-3-O-芸香糖。儿茶素、槲皮素和槲皮素-3-O-β-D-吡喃葡萄糖苷为具有ACE抑制活性的成分。 3. 从木姜冬青95%乙醇提取物的乙酸乙酯部分分离并鉴定了5个化合物: 2-O-β-D-吡喃葡萄糖-6,2´-二羟基-4,4´-二香草酰氧甲基-1,1´-二苯醚(冬青苷)和四个已知化合物:七叶内酯、香草酸、3,4-二甲氧基苯乙酸和vanilloylcalleryanin。冬青苷为新化合物。 4. 从青荚叶95%乙醇提取物的中小极性部分分离并鉴定了9个化合物:β-谷甾醇、β-胡萝卜苷、羽扇豆醇、桦木醇、桦木酸、棕榈酸甘油酯、桂皮酸、6αH-4-烯-3-酮-豆甾醇和6βH-4-烯-3-酮-豆甾醇。 5. 对1985-2006年间天然二苯醚类化合物及活性研究进展进行综述. The in vitro test indicated that the 95% ethanolic extract of the barks of Saurauia napaulensis DC showed α-amylase inhibitory activity, the 95% ethanolic extract of the whole plants of Debregeasia. orientalis showed angiotensin converting enzyme (ACE) inhibitory activity and some fractions of the 95% ethanolic extract of the aerial parts of Helwingia japonica showed protein tyrosine phosphatase (PTP)1B inhibitory activity. In order to investigate components and active compounds of the three plants, they were chemically studied mainly using. Thirty-nine compounds were isolated predominantly by column chromatography identified by spectral methods or comparing them with authentic samples. Further investigation of Ilex litseaefolia Hu et Tang was carried out. Major results are as follows: 1. Twelve compounds were isolation from the 95% ethanolic extract of the barks of S. napaulensis DC. They were identified as auranamide, aurantiamide benzoate, oleanolic acid, β-sitosterol, β-daucosterol, ursolic acid, 2α,3α-dihydroxyurs-12-en-28-oic acid, 2α,3β,24-trihydroxyurs-12-en-28-oic acid, (2S,3S,4R,10E)-2-[(2'R)-2'-hydroxytetracosanoyl amino]-10-octadecene-1,3,4-triol, 2α,3α,24 -trihydroxyolean-12-en-28-oic acid, 2α,3β-dihydroxyurs-12-en-28-oic acid, and 2α,3α,24-trihydroxyurs-12-ene-28-oic acid, respectively, by spectral methods or comparing them with authentic samples. 2. Eighteen compounds were isolation from the 95% ethanolic extract of the whole plants of D. orientalis. They were identified as palmitic acid, henicosanoic acid, henicosanoic acid methyl ester, β-sitosterol, monogynol, betulinic acid, hederagenin, β-daucosterol, 18αH-urs-20(30)-en-3-one, 3,4-seco-urs-20(30)-en-3-oic acid, pomolic acid, (-)-epicatechin, (+)-catechin, quercetin, quercetin 3-O-β-D-glucopyranoside, syringin, syringiaresinol digloside and kaempferol-3-O-rutinose. (+)-Catechin, quercetin and quercetin 3-O-β-D-glucopyranoside were the ACE inhibitory active components. 3. Further phytochemical investigation of the ethyl acetate parts of 95% ethanolic extract of the whole plant of I. litseaefolia afforded 2-O-β-D-glucopyranose-4,4´-di-vanilloyloxymethyl-2,6´-dihydroxy-1,1´-diphenyl ether (ilexiside), esculetin, vanillic acid, 3,4-dimethoxybenzylacetic acid and vanilloylcalleryanin. Ilexiside was new compound. 4. Nine compounds were isolation from the 95% ethanolic extract of the whole plant of H. japonica: β-sitosterol, β-daucosterol, lupeol, betulin, betulinic acid, glycerol monopalmitate, cinnamic acid, stignast-4-en-6β-3-one and stignast-4-en-6α-3-one 5.Diphenyl ether compounds from nature between 1985-2006 were summarized.

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采用微波消解、电感耦合高频等离子体原子发射光谱(ICP-AES)的方法,对62份不同小麦品种(系)中锌、铁、铜、钙、钠和钾的含量进行了测定。同时利用红外线品质测定仪对主要品质指标粗蛋白、湿面筋、沉降值进行了测定。结果表明,不同小麦品种(系)中各种矿质元素的含量存在差异,2006年小麦品种中铁含量变幅为18.55-58.19 ug/g,平均为30.83ug/g ,最高与最低的相差39.64ug/g;锌含量变幅为5.70-25.80 ug/g,平均为15.13ug/g ,最高与最低相差20.10ug/g。2008年小麦品种(系)中铁含量变幅为16.68-52.25 ug/g,平均为30.10ug/g,最高与最低相差35.58ug/g;锌含量变幅为12.29-33.47 ug/g,平均为21.11ug/g,最高与最低相差21.18ug/g;钙含量变幅为167.53-348.80ug/g,平均为248.59ug/g,最高与最低相差192.59ug/g;铜含量变幅为2.32-5.83 ug/g,平均为2.98ug/g,最高与最低的相差3.61ug/g;钾含量变幅为1822.71-4414.91 ug/g,平均为2617.87ug/g,最高与最低的相差2634.72ug/g;钠含量变幅为10.25-39.82 ug/g,平均为23.05ug/g,最高与最低的相差29.57ug/g。 两年不同小麦品种(系)中矿质元素的含量分析结果表明:铁、铜、钙、钠和钾含量年际变化不明显,说明小麦对铁、铜、钙、钠和钾的吸收较稳定;锌含量变化较大,可能受环境的影响比较大。分析各矿质元素含量与粗蛋白、湿面筋、沉降值及元素之间的相关关系,结果表明,锌含量与粗蛋白含量呈极显著正相关关系,相关系数为0.317,与湿面筋含量之间呈显著正相关,相关系数达到0.246;铁含量与粗蛋白含量呈显著的正相关关系,相关系数是0.262;铜、钙、钠和钾含量与粗蛋白含量、湿面筋和沉降值之间存在正相关,但不显著,其中钠与沉降值之间为负相关。表明施锌或铁对提高小麦粗蛋白和湿面筋有显著效应,其余矿质元素有促进作用但不明显。 利用RAPD分子标记技术对川育23、41058、川育20及其父母本进行分析,力图从分子水平找到小麦矿质元素含量之间的差异性,琼脂糖电泳结果表明不同的小麦品种(系)间扩增出了差异条带。 以上研究结果,将对筛选“微量营养强化型”小麦新材料,选育“微量营养强化型”小麦新品种奠定基础。 62 different wheat cultivars was digested with HNO3 in a tightly closed vessel heated under micro-wave,then contents of zinc,iron,copper,calcium,sodium and potassium were determined by inductively coupled plasma-atomic emission spectroscopy(ICP-AES).The main indexes of wheat quality such as total protein、wet glu and sedimentation volume were detected by Infratec 1255 Food & Feed Analyzer at the same time.The obtained results showed that variation for all of the mineral elements concentrations among different cultivars were observed .In 2006, the amplitude variation of the iron content was 18.55-58.19 ug/g,the average value was 30.83ug/g,and 39.64ug/g between the highest-content cultivar and the lowest one; the amplitude variation of the zinc content was 5.70-25.8 ug/g,the average value was 15.13ug/g,and 20.10ug/g between the highest-content cultivar and the lowest one.In 2008, the amplitude variation of the iron content was 16.68-52.25 ug/g,the average value was 30.10ug/g,and 35.58ug/g between the highest-content cultivar and the lowest one; the amplitude variation of the zinc content was 12.29-33.47 ug/g,the average value was 21.11ug/g,and 21.18ug/g between the highest-content cultivar and the lowest one; the amplitude variation of the calcium content was 167.53-348.80ug/g,the average value was 248.59ug/g,and 192.59ug/g between the highest-content cultivar and the lowest one; the amplitude variation of the copper content was 2.32-5.83 ug/g,the average value was 2.98ug/g,and 3.61ug/g between the highest-content cultivar and the lowest one; the amplitude variation of the potassium content was 1822.71-4414.91 ug/g,the average value was 2617.87ug/g,and 2634.72ug/g between the highest-content cultivar and the lowest one; the amplitude variation of the sodium content was 10.25-39.82 ug/g,the average value was 23.05ug/g,and 29.57ug/g between the highest-content cultivar and the lowest one. Analysis was made on the annual variation of mineral elements content in different Wheat cultivars ,the result shows:there is no obvious difference of iron ,copper ,sodium、calcium and potassium concentrations in wheat cultivars, suggesting the absorption of the iron, copper, sodium、calcium and potassium by wheat are relatively steady ,but zinc concentrations change obviously ,maybe influenced heavily by environment . The correlation between mineral elements 、mineral elements and total protein、mineral elements and sedimentation volume as well as mineral elements and wet glut were analysed in this paper, the result showed that there was significant positive correlation between zinc content and total protein (the correlation coefficient is 0.317), positive correlation between zinc content and wet glu (the correlation coefficient is 0.246), positive correlation between iron content and total protein (the correlation coefficient is 0.262). there was positive but not obvious correlation between the contents of copper, calcium, sodium or potassium and total protein, wet glut or sedimentation volume,among which was negative correlation between sodium and sedimentation volume.It was indicated zinc or iron fertilization has prominent effects in improving the total protein in wheat, the rest mineral elements have Non- obvious facilitation. The study then forecasted the genetic difference of different wheat by the molecular marker of RAPD in order to find differences in molecular level. Chuanyu23、41058、chuanyu20 as well as their male and female parents were analysed by RAPD markers,Agarose gel electrophoresis of DNA revealed the appearance of differential bands . The above-mentioned results of this study establish the foundation to screening the new materials of wheat of " strengthening type of micro- nutrition ", and to breeding the new wheat cultivars of" strengthening type of micro- nutrition ".

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为了评估低剂量X射线连续辐射对BALB/c小鼠健康机体免疫系统的影响,实验采用X射线全身连续照射BALB/c小鼠,照射第一天剂量为0.07Gy,剂量率0.2Gy/min,之后每天照射0.08Gy,共照射12d,累积剂量1.03Gy,照射后24和48h取血、胸腺和脾脏。流式细胞仪检测免疫细胞周期和凋亡的变化,胸腺和脾脏指数用重量法获取。实验结果表明,小鼠胸腺细胞的周期在照射后24h被阻滞在G2/M期;外周血淋巴和胸腺细胞周期48h被阻滞在G0/G1期,细胞凋亡比例在照射后两个时间点都显著增加;脾脏淋巴细胞周期24h被阻滞在G0/G1期,48h被阻滞在S期,细胞凋亡比例在24和48h显著减少;脾脏指数在照射后48h显著减少。故低剂量X射线连续全身照射BALB/c小鼠可激活免疫细胞不同的周期监测点,引起免疫细胞凋亡比例发生变化,造成一定的辐射损伤,且这种影响随着免疫器官的不同而不同。

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依托中国科学院近代物理研究所的HIRFLCSR重离子冷却储存环,研制了肿瘤组织诊断用对扇形正电子断层影像(DPET,doublesectorpositronemissiontomography)探测器。介绍了肿瘤组织诊断用DPET探测器的晶体构形、传输光导选择、信号读出电路设计和电子学获取系统,给出了探测器探测单元的一些测试结果和结果讨论。

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用14MeV中子轰击天然锇靶,取道~(192)Os(n,α)反应生成~(189)W。利用改进的锇蒸馏装置蒸馏OsO_4,完成锇与反应产物的分离;通过四苯砷铼沉淀除去铼。使用HPGe探测器测量了分离的钨样品的γ射线谱,该γ射线谱显示钨样品中杂质元素的去污是令人满意的。

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110 ke V Fe+ 离子注入原卟啉 IX二钠盐薄膜样品后的一些谱学分析结果表明 ,低能铁离子束辐照可以导致生物分子的损伤和化学改性 ,并且初步证实注入铁离子在样品分子中慢化沉积后能形成含铁的金属络合物 ,即注入铁离子的质量沉积。

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In this work, the neutron radiation field at Heavy Ion Research Facility in Lanzhou (HIRFL) was investigated. Total neutron yields, spectra and angular distributions in the bombardment of various thick targets by C-12 and O-18 ions with energies up to 75 MeV/u were obtained using the activation method. The neutron dose equivalent rates of 60 MeV/u O-18 on various thick targets at different angles were measured with a modified A-B remmeter. Our results are compared with those of other reports.