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1.
以苗圃中生长的、盛花期时的淫羊藿属(Epimedium)植物叶片为材料,利用高效液相色谱仪测定不同物种叶片中4种药效黄酮苷的含量,同时测量叶片面积、叶片长宽比等参数.统计分析的结果表明,淫羊藿属不同物种的叶片形态与黄酮苷的含量之间存在一定的联系:活性成分含量高的淫羊藿,其叶片面积较小,形状多呈卵形, 叶片革质化程度也较低.  相似文献   

2.
糖基化终产物(AGEs)在糖尿病肾病的发生发展过程中起着重要的作用.但目前其作用机制还不太清楚.通过体外乳鼠肾脏细胞的原代培养,探讨AGEs对肾细胞的损伤作用及可能的作用机制.取出生3天的SD大鼠的乳鼠肾脏进行体外原代细胞培养,并取传代到4-6代的细胞进行实验研究.分别用不同浓度的AGEs(0、1.2、2.5、5、10、20 mg/ml),不同的作用时间(6、12、18、24 h)作用于体外培养的肾细胞,用MTT法检测AGEs对肾细胞的增殖情况,用酶试剂盒法检测AGEs对肾细胞培养液中乳酸脱氢酶(LDH)、β-N-乙酰氨基葡萄糖苷酶(NAG)的含量,以及肾细胞内还原型谷胱甘肽(GSH)和超氧化物歧化酶(SOD)的含量.实验结果表明随着AGEs作用肾细胞时间的延长和浓度的增加,细胞存活率、细胞内GSH含量和SOD活性均逐渐下降,而细胞培养液中LDH和NAG的含量则逐渐升高,与正常培养的对照组细胞相比差异非常显著(P<0.001),并且AGEs对细胞的作用与其浓度和作用时间呈显著的量效关系.实验结果说明AGEs对原代培养的肾细胞有明显的损伤作用,并随着AGEs作用浓度的增加和作用时间的延长对肾细胞的损伤越来越严重,实验结果也表明.肾细胞对AGEs的作用很敏感,其损伤细胞的途径和作用机制可能是由于改变了肾细胞膜的通透性和降低肾细胞抗氧化能力,该实验研究也进一步提示了AGEs是导致糖尿病肾脏并发症发生的重要原因之一.  相似文献   

3.
本文探讨蒺藜皂苷(STT)对糖基化终产物(AGEs)形成及AGEs诱导的内皮细胞功能障碍的影响。以荧光法检测AGEs体外形成,MTT法检测细胞存活率,试剂盒方法检测细胞及培养上清液中的一氧化氮(NO)水平、诱导型NO合酶(iNOS)活力和超氧阴离子水平(O2-.)。结果显示STT促进AGEs形成,并加剧AGEs诱导的内皮细胞生长抑制,提高细胞NO分泌,增加iNOS活力和O2-.水平。与海可、替告皂苷元作用进行比较,发现STT的细胞损伤作用可能是海可皂苷元引起的。提示STT未能抑制体外AGEs形成,对AGEs引起的内皮细胞功能障碍无明显保护作用,反而可能通过增强iNOS酶活加剧细胞损伤。  相似文献   

4.
野生珍稀药用植物七叶一枝花的成分含量分析   总被引:1,自引:0,他引:1  
利用分光光度计、高效液相色谱仪和等离子光谱仪对华中地区珍稀药用植物七叶一枝花[Paris polyphylla Smith var.chinensis(Franch.)Hara]根茎的化学成分薯蓣皂甙元、黄酮、19种游离氨基酸、微量元素进行了分析。结果显示:薯蓣皂甙元含量为0.62%,黄酮含量为0.0628%,总游离氨基酸含量为0.33%,微量元素中钙为0.77%,镁为0.20%,钾为0.98%,铁为0.20%,锌为44.8mg/kg,磷为746mg/kg。  相似文献   

5.
微量元素在寻找新活性物质中的应用研究   总被引:5,自引:0,他引:5  
通过对31种中草药的微量元素分析,应用现代生物学和现代医学的观点讨论了微量元素的种类、含量以及不同微量元素谱在生理生化、药理药效上的相关性,提出应用微量元素测定方法寻找新的活性物质和中草药深层开发的可能性。  相似文献   

6.
藏药"君西"广泛应用于藏医药成方制剂中,因在不同炮制方法中所用辅料种类和量的不同,使得"君西"炮制品的药性也不同,国内对其药效研究几乎空白,本实验欲通过研究"君西"炮制后微量元素的变化与药效之间的关系,探讨"君西"的现代药理学作用。藏药"君西"按传统方法炮制,采用原子吸收光谱仪(火焰法、石墨炉法),测定炮制后Ca、Mg、Fe、Mn、Zn、Cu样品含量,结合改良的酚红含量测定法研究对正常小鼠肠推进和胃排空的影响。结果发现,除传统"灰"制的微量元素含量较高于其它组外,余下各组元素含量高低不同。传统"灰"制、传统热制、传统烈制的胃酚红排空率和小肠推进率较其它炮制组高,说明藏药"君西""热"制法对提高胃排空及加速小肠推进有一定积极的作用,但与微量元素含量的多少可能没有必然的联系,提示其治疗作用可能与藏医药传统的"热"制法治疗培根病的理论相一致。  相似文献   

7.
目的观察吡哆胺对糖尿病大鼠视皮质高级糖基化终末产物(AGE)及其受体(RAGE)表达的影响,探讨吡哆胺对视皮质的保护作用。方法健康SD大鼠随机分为正常对照组(NC组)、糖尿病未治疗组(DM组)、糖尿病吡哆胺治疗组(PM组)和氨基胍治疗对照组(AG组)各20只,用链脲佐菌素(STZ)建立糖尿病模型,PM组和AG组分别于造模成功后第二天开始予吡哆胺和氨基胍灌胃。各组于治疗4w和12w后取材,用酶联免疫吸附(ELISA)法定量检测大鼠视皮质中AGEs含量,荧光免疫组化及图像分析半定量检测各组视皮质RAGE的表达。结果糖尿病治疗组和未治疗组血糖无显著性差异。4w时各组AGEs含量无明显差异,12w时PM组视皮质中AGEs含量与AG组、NC组比较差异无统计学意义,与DM组相比显著降低,差异具有统计学意义(P0.05)。PM组视皮质中RAGE表达比DM组显著减少,差异具有统计学意义(P0.05),但高于NC组(P0.05)。结论糖尿病大鼠12w后视皮质中AGEs含量和RAGE的表达高于正常对照组,吡哆胺类似氨基胍可减少AGEs的堆积,还能抑制RAGE的表达,减轻AGEs-RAGE通路作用导致的组织损伤,对视皮质具有一定的保护作用。  相似文献   

8.
筛选靶向结合炎症相关蛋白5-LOX(5-lipoxygenase,5-脂氧合酶)的中药黄酮类天然产物,分析与5-LOX结合的黄酮类成分及其来源中药的共性规律。本研究借助Discovery Studio 2017 R2分子对接和药效团构建模块,结合SPR分子筛选实验,以及关联网络构建的方法进行研究。研究结果显示,来源于17种中药的18个黄酮类小分子中有11个能够与5-LOX结合,并从分子对接以及药效团构建研究中发现其作用的3种方式和共性特征:(1)部分中药黄酮成分(如木犀草素等)通过结构中的B环与5-LOX在活性位点ASP243形成静电中心相结合;(2)部分中药黄酮成分(如芹菜素等)是通过结构中的A环与活性位点VAL520形成疏水键、与活性位点ASP243形成氢键与5-LOX结合;(3)杨梅苷等黄酮类成分由于极性较强,在没有形成疏水键的情况下,也是通过形成静电中心与5-LOX在活性位点ASP243产生相互作用。此外还发现靶向5-LOX的活性中药黄酮类化合物,大多来源于具有利湿、退黄等功效,性味甘苦寒的景天科中药中。本研究发现了部分靶向5-LOX的中药黄酮类成分及其作用方式和共性规律,为开发靶向5-LOX抗肿瘤新药提供思路和方法。  相似文献   

9.
莲属植物类黄酮代谢产物的研究进展   总被引:1,自引:0,他引:1  
莲属(Nelumbo)植物既可药用也可食用, 其中荷叶、藕节、莲子、莲子心、莲房和莲须等皆可入药, 但药效各不相同。迄今为止, 从莲的各组织中共检测出类黄酮多达61个, 包括8个花青素苷、2个黄酮醇、29个黄酮醇苷、1个黄酮、16个黄酮苷(内含13个碳苷黄酮)和5个黄烷醇。该文对莲各组织中所含类黄酮的检测方法、组成、含量及药理等方面的研究进展进行了综述。迄今的研究结果表明, 莲中含有丰富的类黄酮化合物, 且具广泛的药理活性(如抗氧化、抗菌、抗HIV、抗动脉粥样化、提高免疫力和减肥降脂等)。这些资料不仅对今后深入研究莲各部位的类黄酮代谢物及其与药效的关系有重要意义, 而且对保健食品和中药的研发也具有重要的参考价值。  相似文献   

10.
目的:探讨AGEs通过刺激SDF-1/CXCR4轴信号系统对心肌微血管内皮细胞的增值、迁移、管样结果形成的影响以及AMD3100对其的干预作用.方法:用不同浓度的AMD3100作用于浓度为200mg/L的AGEs共孵育的CMECs24h,用MTT法检测细胞活力及增殖能力,并选择合适的干扰浓度(抑制效果居中).随机选取加入AGEs200ml/L的CMECs,加入合适浓度的AMD3100,分别作用24、48、72h,采用MTT法测定AGEs处理前后细胞增值率的变化,并检测AMD3100对增值率的影响;毛细血管管腔样结构形成实验检测对CMECs血管新生的影响和AMD3100对其阻断作用的影响.结果:心肌微血管内皮细胞增殖能力和迁移能力在24h、48h、72h有显著增强;并促进了心肌微血管内皮细胞管样形成(vs P<0.05);CXCR4受体阻断剂AMD3100作用于细胞后,可以显著阻断AGEs对心肌微血管内皮细胞增殖能力和迁移能力和管腔形成(vs P<0.05)的影响.结论:AGEs在早期显著增强了心肌微血管内皮细胞的增殖、迁移和管样结构形成的能力,其作用机制可能与SDF-1/CXCR4轴信号通路有关.  相似文献   

11.
武婕  李玉环  李增兵  方正  钟豫 《生态学报》2014,34(6):1596-1605
基于地统计学和GIS技术相结合的方法,研究了南四湖区农田土壤有机质和微量元素的空间分布特征及其影响因素。结果表明,土壤有机质和微量元素均属中等变异程度,除硼符合正态分布外,其余土壤属性均符合对数正态分布。结构分析表明,除硼为纯块金效应外,土壤有机质和其它微量元素空间自相关性较强,其中结构性因素起主导作用。克里格插值结果表明,土壤有机质分布总体趋势为由北向南逐渐降低,锰、铜、锌分布总体趋势为中部高,南北两端低。影响因素分析表明,土壤类型、耕层质地、坡度、土地利用类型和地貌类型对土壤有机质均有显著影响。土壤类型主要是由于成土母质的差异影响土壤有机质的高低与分布,随质地由砂变粘、坡度由低变高,土壤有机质含量逐步升高,田间管理水平的差异是造成不同土地利用类型下土壤有机质含量差异的主要原因。微量元素中,除硼不受影响外,铁、锰、铜和锌与土壤类型、耕层质地、坡度、土地利用类型和地貌类型密切相关。  相似文献   

12.
A 9-year manipulative experiment with nitrogen (N) and water addition, simulating increasing N deposition and changing precipitation regime, was conducted to investigate the bioavailability of trace elements, iron (Fe), manganese (Mn), copper (Cu), and zinc (Zn) in soil, and their uptake by plants under the two environmental change factors in a semi-arid grassland of Inner Mongolia. We measured concentrations of trace elements in soil and in foliage of five common herbaceous species including 3 forbs and 2 grasses. In addition, bioaccumulation factors (BAF, the ratio of the chemical concentration in the organism and the chemical concentration in the growth substrate) and foliar Fe:Mn ratio in each plant was calculated. Our results showed that soil available Fe, Mn and Cu concentrations increased under N addition and were negatively correlated with both soil pH and cation exchange capacity. Water addition partly counteracted the positive effects of N addition on available trace element concentrations in the soil. Foliar Mn, Cu and Zn concentrations increased but Fe concentration decreased with N addition, resulting in foliar elemental imbalances among Fe and other selected trace elements. Water addition alleviated the effect of N addition. Forbs are more likely to suffer from Mn toxicity and Fe deficiency than grass species, indicating more sensitivity to changing elemental bioavailability in soil. Our results suggested that soil acidification due to N deposition may accelerate trace element cycling and lead to elemental imbalance in soil–plant systems of semi-arid grasslands and these impacts of N deposition on semi-arid grasslands were affected by water addition. These findings indicate an important role for soil trace elements in maintaining ecosystem functions associated with atmospheric N deposition and changing precipitation regimes in the future.  相似文献   

13.
H Zhao  L Wu  T Chai  Y Zhang  J Tan  S Ma 《Journal of plant physiology》2012,169(13):1243-1252
Synchrotron radiation X-ray fluorescence (SRXRF) and inductively coupled plasma mass spectrometry were used to estimate major, minor and trace elements in Cu-, Zn- and Mn-treated Phytolacca americana. The effects of the addition of Cu, Zn and Mn on morphological parameters, such as root length, shoot height, and fresh and dry weights of shoots and roots, were also examined. In addition, the activities of superoxide dismutase (SOD), ascorbate peroxidase (APX), guaiacol peroxidases (GPX) and catalase (CAT) and the expression of Fe-SOD, Cu/Zn-SOD, metallothionein-2 and glutathione S-transferase (GST) exposed to the highest amounts of Cu, Zn or Mn were detected. Our results confirmed the following: (1) Zn supplementation leads to chlorosis, disturbed elemental homeostasis and decreased concentrations of micro- and macroelements such as Fe, Mg, Mn, Ca and K. Cu competed with Fe, Mn and Zn uptake in plants supplemented with 25μM Cu. However, no antagonistic interactions took place between Cu, Zn, Mn and Fe uptake in plants supplemented with 100μM Cu. Mn supplementation at various concentrations had no negative effects on elemental deficits. Mn was co-located with high concentrations of Fe and Zn in mature leaves and the concentrations of macro elements were unchanged. (2) P. americana supplemented with increased concentrations of Zn and Cu exhibited lower biomass production and reduced plant growth. (3) When plants were supplemented with the highest Zn and Cu concentrations, symptoms of toxicity corresponded to decreased SOD or CAT activities and increased APX and GPX activities. However, Mn tolerance corresponded to increased SOD and CAT activities and decreased POD and APX activities. Our study revealed that heavy metals partially exert toxicity by disturbing the nutrient balance and modifying enzyme activities that induce damage in plants. However, P. americana has evolved hyper accumulating mechanisms to maintain elemental balance and redox homeostasis under excess Mn.  相似文献   

14.
Levels, distribution and chemical forms of trace elements in food plants   总被引:2,自引:0,他引:2  
The content of trace elements in plants can vary widely, depending upon the composition of the soil in which they grow, other environmental factors, and the species or cultivar of the plant. A high growth rate of the plant may cause internal 'dilution' of trace elements. Complex formation with soil organic colloids and compounds, cell wall material and ligands in and inside the cell membranes are of critical importance in uptake, though most evidence shows that it is the free metal ion in the external solution that is absorbed; the detailed mechanisms are still unknown. Other processes such as excretion of organic compounds, reductants and hydrogen ions from the root greatly alter availability of trace metals, and iron has to be reduced to the ferrous form before uptake. The mean composition of plant shoots is affected by age and season; element mobility in the xylem and phloem determines translocation, and hence concentrations in individual parts of the plant. The rate of retranslocation can be strongly affected by the abundance of the element. Symptoms of deficiency or excess are well documented, but are often not dependable. The essentiality of the trace metals depends upon their function as part of enzymes, and these are briefly reviewed, with stress on processes in plants. Only a small fraction of the total amount of an element is bound in the enzyme; of the remainder, some is present as the free metal ion (Mn) or as complexes of small molecular mass (Cu, Zn, Ni, Fe), the rest being bound to cell wall material. Certain species or genotypes have resistance against high levels of some elements in the soil. Several mechanisms may be involved, one being very strong binding to root cell walls. There are also large genetic differences in susceptibility to trace element deficiencies.  相似文献   

15.
 本文研究了羊草(Aneurolepidium chinense)草地割草场3种植物必需的微量元素锰、铜、锌的含量特征。结果表明,在生长季各时期,优势种羊草各器官元素含量有很大变化,总的趋势是:根>根茎>茎>叶>穗(Zn:叶>茎),各器官之间元素含量差异显著(P<0.05)。其它种类植物根中锰、铜、锌含量也显著高于地上各器官。羊草地上部锰、铜、锌积累量在生长季中的变化近似于“S”型曲线,但各元素曲线最高点出现的时间不同。寸草苔(Carex duriuscula)和针蔺(Heleocharis acicularis)地上部锰、铜、锌积累量变化与生物量变化相似,基本为双峰型曲线。三种元素在群落中的分布规律是:根>茎>叶>穗,与生物量分布规律相同。但锰、铜在地上各器宫中积累量占植物总积累量的比率低于相应的生物量比率,而锌这两者的比率则与生物量比率相近。群落中锰、铜、锌积累量与根层土壤中锰、铜、锌总量之比分别为0.10%,0.33%和0.09%。  相似文献   

16.
The purpose of this study was to investigate the content of trace elements in relation to the composition of domestic herbal mixtures. Cluster analysis, principal components analysis, and self-organizing maps were applied to identify existing relationships. The concentrations of Ni, Pb, Cd, Cr, Cu, Fe, Mn, Zn in 81 samples of herbal mixtures were determined with application of FAAS. The study showed that the levels of trace elements in some herbal mixtures of the same composition were comparable. The projection of herbal samples onto topological maps of adjustable sizes allowed recognition of the identical herbal preparations characterized by dissimilar levels of trace elements. The elements which played the most important role in recognition of the herbal samples were Mn, Ni, Zn and partly Cu, Fe and Cd.  相似文献   

17.
A growth experiment with 108 lambs (breed: German Merino Landsheep) was carried out to examine the effect of gender, body weight (BW) and feeding intensity on the deposition of Fe, Zn, Cu and Mn in the empty body (whole animal minus contents of the gastrointestinal tract and bladder). The lambs (50% female and 50% male animals) were fed at three feeding levels ('low', 'medium' and 'high' by varying daily amounts of concentrate and hay) and slaughtered at different final BWs (30, 45 or 55 kg). Six male and six female animals were killed at a BW of 18 kg representing the animals' BW at the beginning of the comparative slaughter experiment. There were significant main effects for the treatments growth rate and final weight on the daily rate of accretion of the trace elements examined. Feeding intensity had a marked influence on the accretion rate for Fe (P < 0.001), Zn (P < 0.001), Cu (P < 0.001) and Mn (P = 0.003). With increasing feeding intensity (low, medium, high) the daily deposition of these trace elements increased (4.4, 5.2, 6.6 mg/day for Fe; 4.9, 5.5, 6.9 mg/day for Zn; 0.20, 0.36, 0.44 mg/day for Cu; 0.14, 0.16, 0.21 mg/day for Mn). Heavier final BW led to increased daily retention of Zn (P < 0.001) and Mn (P = 0.002). Gender had a marked influence only on the accretion rate for Zn (P < 0.001). Ram lambs had a higher daily deposition of this element than female lambs. Related to 1000 g empty body gain, the following concentrations were found for the trace elements examined: Fe 26.1 mg, Zn 30.0 mg, Cu 1.41 mg and Mn 1.04 mg. A feeding influence was given for Zn (P < 0.001) and Cu (P = 0.039). Feeding level low had higher Zn and lower Cu concentrations. Male animals showed less Fe (P < 0.001) and Zn (P = 0.034) per kg empty body gain than females.  相似文献   

18.
Despite the nutritional value of Colophospermum mopane to browser's diets, there is still insufficient knowledge on the effect of browsers on concentrations of these trace elements. A field experiment was conducted in Musina Nature Reserve, Limpopo Province, South Africa, to determine the effect of pruning on the concentration of trace elements in mopane leaves. Samples were analysed for iron (Fe), manganese (Mn), boron (B), molybdenum (Mo), copper (Cu), zinc (Zn), cobalt (Co), fluoride (F) and selenium (Se) using the inductively coupled plasma atomic emission spectrometry technique. The effect of pruning was tested using the two‐tailed t‐test: two‐sample assuming equal variance and two‐tailed Mann–Whitney U‐test. Results showed that the concentration of trace elements in the control and pruned trees varies slightly through the year. Fe, Mn, Mo, Cu, Zn and Se are higher during leaf flush, but declined as the leaves matured and aged. This study concluded that simulated browsing had no significant effect on the concentration of trace elements in the mopane leaves. Seasonal variation in the amount of trace elements has implications on the distribution of browsers in the mopane woodland.  相似文献   

19.
The present study aimed to evaluate trace mineral status of organic dairy herds in northern Spain and the sources of minerals in different types of feed. Blood samples from organic and conventional dairy cattle and feed samples from the respective farms were analysed by inductively coupled plasma mass spectrometry to determine the concentrations of the essential trace elements (cobalt (Co), chromium (Cr), copper (Cu), iron (Fe), iodine (I), manganese (Mn), molybdenum (Mo), nickel (Ni), selenium (Se) and zinc (Zn)) and toxic trace elements (arsenic (As), cadmium (Cd), mercury (Hg) and lead (Pb)). Overall, no differences between organic and conventional farms were detected in serum concentrations of essential and toxic trace elements (except for higher concentrations of Cd on the organic farms), although a high level of inter-farm variation was detected in the organic systems, indicating that organic production greatly depends on the specific local conditions. The dietary concentrations of the essential trace elements I, Cu, Se and Zn were significantly higher in the conventional than in the organic systems, which can be attributed to the high concentration of these minerals in the concentrate feed. No differences in the concentrations of trace minerals were found in the other types of feed. Multivariate chemometric analysis was conducted to determine the contribution of different feed sources to the trace element status of the cattle. Concentrate samples were mainly associated with Co, Cu, I, Se and Zn (i.e. with the elements supplemented in this type of feed). However, pasture and grass silage were associated with soil-derived elements (As, Cr, Fe and Pb) which cattle may thus ingest during grazing.  相似文献   

20.
不同利用强度下绿洲农田土壤微量元素有效含量特征   总被引:13,自引:0,他引:13  
以地处极端干旱背景下的塔里木盆地南缘策勒绿洲为研究区,以绿洲化为视角,根据当地农民耕作习惯于2005年选择4块试验农田,分别代表当地典型的农田利用强度。基于单项指数(Ei)和综合指数(Ec)相结合的评价方法,分析了绿洲农田在不同利用强度下的土壤Fe、Cu、Mn、Zn等微量元素有效性,探讨了土壤微量元素与人为耕作管理措施之间的关系。结果表明:人为耕作管理强度会对土壤微量元素有效含量产生重要影响,绿洲不同位置农田因施肥强度和管理方式的差别,其土壤微量元素有效含量特征存在显著差异。绿洲内部农田土壤有效Fe、Cu、Mn、Zn含量显著高于绿洲边缘各样地,新垦农田土壤有效Fe、Cu、Zn含量均低于对照样地;绿洲内部农田土壤微量元素有效性最高,新垦农田最低;农田土壤微量元素有效性与土壤有机质存在显著的正相关关系。  相似文献   

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