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为探讨土家族药刺老苞根皮对大鼠骨折模型胫骨矿物元素的影响,将250只SD大鼠(雌雄各半)随机分成对照组、模型组和刺老苞根皮黄酮高、中、低(30、20、10 mg·kg-1)剂量组,每组10只,分别灌胃相应药物,每日1次,连续4周,用电感耦合等离子体质谱法(ICP - MS)测定了给药第4天、第7天、第14天、第21天和... 相似文献
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新冠肺炎疫情爆发以来,临床上通过老药新用的策略发展小分子药物,以用于治疗新冠肺炎。在短时间内迅速从抗病毒、抗炎药物中发现能够用于新冠治疗的药物,如洛匹那韦/利托那韦、磷酸氯喹等。结合几款典型的药物,浅析它们在抗击新冠肺炎中的应用。 相似文献
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河南老湾金矿床稀土元素地球化学对成矿物质来源的示踪 总被引:3,自引:0,他引:3
采用ICP-MS方法测定了河南桐柏老湾金矿床成矿期主成矿阶段石英和黄铁矿的稀土元素组成,以及老湾花岗岩中石英的稀土元素组成,并结合矿床矿石、老湾花岗岩和赋矿围岩全岩的稀土元素组成的对比研究,以期示踪成矿物质来源。分析结果显示,矿床石英和黄铁矿的稀土元素平均总量为13.39×10-6,花岗岩中的石英为6.68×10-6,显著低于矿床矿石、花岗岩和围岩全岩,而矿床石英和黄铁矿的δEu,δCe,轻重稀土分异程度以及稀土元素配分模型都与花岗岩中的石英非常相似,显著不同于赋矿围岩。矿床相关地质体的稀土元素特征表明,成矿流体主要源自老湾花岗岩浆分异的岩浆流体,而非变质流体。 相似文献
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采用水蒸气蒸馏法从青蒿、桂枝及其药对中提取挥发油成分,利用气相色谱-质谱(GC-MS)联用技术进行分离检测,通过化学计量学解析法(CRM)对重叠色谱峰解析,并结合程序升温保留指数辅助定性.从药对及其单味药青蒿、桂枝中分别鉴定出69、66、68种挥发油;组成药对后,单味药成分减少,新成分增加,药对与单味药挥发油共存17种组分,它们是cis-细辛醚、丁子香烯、丁子香烯环氧化物等成分,占药对挥发油总含量的35.82%;而药对中挥发油的主要成分是(E)-桂皮醛(18.32%)和cis-细辛醚(10.20%)等,其含量并非单味药含量的简单相加,相关作用机理有待进一步研究. 相似文献
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广东四会十月桔种植土壤中微量元素分析 总被引:4,自引:2,他引:2
用火焰原子吸收分光光度法和阳极溶出伏安法对广东四会9个地区的十月桔及其种植土壤中11种元素进行了测定。结果表明,四会地区十月桔富含人体有益元素,而有害元素含量极低,是一种有较高营养价值及安全的食品,土壤中各元素含量范围广,但十月桔对同一元素具有相应的富集特征。 相似文献
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对橙色红曲菌As3.4384及其诱变菌株大米固态发酵物中桔霉素和色素的HPLC分离进行了优化,采用Symmetry C18(250mm×4.6mmi.d.,5μm)色谱柱,流动相为乙腈-水(磷酸调pH3.0,77∶23,V/V),分别采用紫外检测器(UV=254nm)、荧光检测器(λex=331nm,λem=500nm)及两者串联对桔霉素和色素进行了监测。通过ESI-MS对色素进行了鉴定,并测定了经橙色红曲菌As3.4384及其诱变菌株于30℃发酵14d后的大米、糯米、小黄米、燕麦米和红米中桔霉素含量。结果表明:ESI-MS鉴定的两种色素分别为红曲菌素和红曲黄素,橙色红曲菌As3.4384发酵后的大米、糯米、小黄米、燕麦米和红米中桔霉素含量分别为151.4、100.5、5.06、80.5和150.5mg/kg,而诱变菌株发酵后的大米、糯米、小黄米、燕麦米和红米中桔霉素含量分别为0.218、3.86、0.223、2.45和4.05mg/kg。 相似文献
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丁基黄原酸盐为有色金属选矿工艺中常用的捕集剂,并且在人造纤维和制药工业中广泛应用。由于黄药具有恶臭和毒性,会污染水系和水生生物,因此对使用黄药的单位排放水中的微量黄药监测已列为环保监测项目之一。微量黄药的测定一般采用比色法,作者曾研究过离子选择性电极法。本工作报导用甲基异丁酮萃取黄原酸铜火焰原子吸收测定铜从而间接测出水中微量黄药的量。方法灵敏、快速,用于选矿废水中微量黄药的测定,取得了满意的结果。 相似文献
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含微量元素的中药对老年病的治疗 总被引:16,自引:0,他引:16
微量元素摄取过多或不足,会引发老年病.中药含有微量元素,根据不同药物含的微量元素不同.来治疗因微量元素缺乏发生的老年病有一定价值.本文综合报道了一些老年病治疗. 相似文献
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应用原子吸收分光光度法对济南市健康老年人血清中铜、锌、镁含量进行了测定。结果表明,健康老年人血液铜、锌水平低,但铜、锌比值正常,而镁的含量则较高。提示这组健康老年人未患心、脑血管疾病及糖尿病的原因可能与铜、锌、镁等微量元素有关。 相似文献
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G. N. Kramer L. De Angelis J. Pauwels W. Ooghe J. J. Belliardo 《Fresenius' Journal of Analytical Chemistry》1988,332(6):694-697
Summary The possibility of producing fruit juice reference materials is conditioned by the availability of a method which allows the transformation of the original juice or concentrate into a better physically stable form. Therefore a feasibility study of the transformation of orange juice by freeze-drying was carried out. In general, the obtained powder is hygroscopic, and tends to agglomerate into large solid lumps. Under optimal conditions of freeze-drying combined with redrying of the powder before closing the bottles, a slightly cohesive but physically stable yellow orange powder can however be obtained. Compared to the original juice, this shows no loss of reducing sugars and has a normal glucose-fructose ratio. Moreover, most aminoacids e.g. asparagine, methionine, lysine and arginine are not affected by freeze-drying. Based on the study of a limited number of important fruit juice parameters, it may be concluded that freeze-drying seems very promising in order to obtain an orange juice reference material, which after redissolution in water keeps the original chemical orange juice properties.
Gefriertrocknung von Orangensaft für die Herstellung von Referenzmaterialien相似文献
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微量元素对老年人健康的作用与危害 总被引:2,自引:1,他引:2
介绍了微量元素的生理功能,微量元素与衰老,长寿和老年人冠心病,高血压,脑血管疾病,肿瘤,糖尿病等五种常见病的关系。还特别介绍了锌对人类健康的作用和铅对人类健康的危害。老年人体内有益的微量元素,如铁,锌,锰,铬,硒等比较缺乏,相反镍,铅,铝等有害的微量元素比较高。长寿老人头发中有益微量元素锰,钴,硒,铜,锌,铬等均有较高水平。人要长寿,必须维持体内微量元素的水平,微量元素过低或者过高应及时通过食疗或药物治疗进行调节。 相似文献
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Banide EV Ortin Y Seward CM Harrington LE Müller-Bunz H McGlinchey MJ 《Chemistry (Weinheim an der Bergstrasse, Germany)》2006,12(12):3275-3286
1-Phenyl-3,3-biphenyleneallene (2), the base-catalyzed rearrangement product of 9-phenylethynylfluorene (1) yields a yellow, head-to-tail dimer 6 that, upon gentle warming, is converted to the red tail-to-tail isomer trans-3,4-diphenyl-1,2-bis(fluorenylidene)cyclobutane (7), in which the two fluorenylidene moieties severely overlap. The helical sense of the fluorenylidene moieties in 7 matches that of the phenyl substituents, and the interplanar angle between the fluorenylidene moieties is 41 degrees . At 80 degrees C, 6 isomerizes to orange cis-3,4-diphenyl-1,2-bis(fluorenylidene)cyclobutane (8), which at 110 degrees C is converted to orange trans diastereomer 9, whereby the helicity of the overlapping fluorenylidene moieties is reversed from that in 7 such that they are aligned with the ring hydrogen atoms, and the interplanar angle between the fluorenylidene moieties is now 60 degrees . At 180 degrees C, 6 rearranges to dispirodihydrotetracene 3 and blue, electroluminescent diindenotetracene 4, which is readily oxidized to peroxide 5. In the solid state, both 3 and 4 adopt structures with Ci symmetry (only an inversion center) such that the central polycyclic framework is nonplanar. Deprotonation of yellow head-to-tail allene dimer 6 with tBuOK in DMSO and reprotonation with HOAc yields the [1,3]-hydrogen migration product 10, in which the proton originally on the cyclobutane ring is now sited at C9 on the exocyclic fluorenyl substituent. Analogously, deprotonation and reprotonation of orange dimer 9 furnishes [1,3]-hydrogen migration product 11. Side product 17, formed during the synthesis of 1 from 9-phenylethynylfluoren-9-ol, BF3 and Et3SiH, was shown to be a silyl-indene spiro-linked to C9 of fluorene. All products were characterized by NMR spectroscopy and X-ray crystallography, and the mechanisms of these interconversions are discussed. 相似文献
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Koji Takagi Yukimi Nishikawa Naomi Nishioka Hideo Kunisada Yasuo Yuki 《Journal of polymer science. Part A, Polymer chemistry》2002,40(22):3927-3937
The synthesis and characterization of tropone‐containing π‐conjugated oligomers were investigated. Two kinds of oligomers [1,4‐phenylene type ( 4a – 4e ) and 2,5‐thienylene type ( 5 )] were successfully obtained by the Wittig polycondensation technique, in which the tropone content could be controlled by the monomer feed ratio for the 1,4‐phenylene‐type oligomers. The absorption maximum blueshifted and the emission intensity decreased with an increase in the tropone content in the oligomers. The emissive color could be tuned by the selection of the aromatic ring; that is, 4a – 4e emitted orange‐yellow light and 5 emitted either orange‐yellow or red light according to the excitation wavelength. © 2002 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 40: 3927–3937, 2002 相似文献
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近红外光谱快速测定红花逆流提取过程中羟基红花黄色素A的含量 总被引:4,自引:0,他引:4
采用近红外光谱(NIRS)透射法对红花罐组式逆流提取过程中羟基红花黄色素A(Hydroxysafflor yellow A,HSYA)的含量进行快速无损的测定.在红花逆流提取过程中,以高效液相色谱法(HPLC)为对照分析方法,测定提取液中羟基红花黄色素A的含量,运用偏最小二乘(PLS)法建立NIR光谱与羟基红花黄色素A的HPLC分析值之间多元校正模型,并对逆流提取过程的未知样本进行含量预测.校正模型相关系数达到0.982,预测相关系数达到0.965,RMSEC和RMSEP分别为0.053和0.075,RSEC和RSEP分别为3.96%和5.25%.结果表明,NIRS可以作为一种准确、快速、无损的检测方法用于检测中药逆流提取过程有效成分含量变化规律. 相似文献
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da Silva CE Garcia HC Diniz R Spezialli NL Yoshida MI Edwards HG de Oliveira LF 《The journal of physical chemistry. A》2007,111(47):11990-11995
This work presents a comparative study of dihydrated and anhydrous forms of potassium croconate crystals by vibrational spectroscopy, X-ray powder diffraction, and thermogravimetry. These compounds have different colors (dihydrated is orange, and dehydrated is yellow) due to the presence of coordinated water molecules. X-ray diffraction patterns show that the unit cell of the yellow compound is smaller than that of the orange analogue, suggesting that the croconate ion layers are more closely bonded in this salt. The loss of water is reversible due to the potassium cation size which is intermediate between small (Li+ and Na+) and large (Rb+ and Cs+) alkaline metal ions. However, the hydrated compound (orange) is more stable, and with a small quantity of water the yellow compound is quickly converted to the orange compound. A diagnostic feature of the Raman spectrum for the orange (hydrated) and yellow (anhydrous) analogues is the singlet at 1240 cm(-1) in the former, assigned to a nu(CC) + delta(CCC) + nu(CO) + beta(CO) mode of E'2 symmetry, which splits in the yellow form to a doublet at 1256 and 1232 cm(-1). 相似文献
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Antonella Di Francesco Vincenzo Cunsolo Rosaria Saletti Birte Svensson Vera Muccilli Pasquale De Vita Salvatore Foti 《Molecules (Basel, Switzerland)》2021,26(9)
Wheat represents one of the most important cereals for mankind. However, since wheat proteins are also the causative agent of several adverse reactions, during the last decades, consumers have shown an increasing interest in the old wheat genotypes, which are generally perceived as more “natural” and healthier than the modern ones. Comparison of nutritional value for modern and old wheat genotypes is still controversial, and to evaluate the real impact of these foods on human health comparative experiments involving old and modern genotypes are desirable. The nutritional quality of grain is correlated with its proteomic composition that depends on the interplay between the genetic characteristics of the plant and external factors related to the environment. We report here the label-free shotgun quantitative comparison of the metabolic protein fractions of two old Sicilian landraces (Russello and Timilia) and the modern variety Simeto, from the 2010–2011 and 2011–2012 growing seasons. The overall results show that Timilia presents the major differences with respect to the other two genotypes investigated. These differences may be related to different defense mechanisms and some other peculiar properties of these genotypes. On the other hand, our results confirm previous results leading to the conclusion that with respect to a nutritional value evaluation, there is a substantial equivalence between old and modern wheat genotypes. Data are available via ProteomeXchange with identifier <PXD024204>. 相似文献