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1.
Polygonum capitatum, a traditional Miao medicinal plant, has significant effects on the treatment of urinary system infections and pyelonephritis. However, no study about the comprehensive quality evaluation of P. capitatum has been reported. In this contribution, a rapid and validated method based on HPLC coupled with triple quadrupole MS was established for the simultaneous determination of six active flavonoids, six phenolic acids, and a lignan in extracts of P. capitatum. These compounds were separated within 10 min on a C18 analytical column with gradient elution. All analyses were performed on an Agilent XDB C18 column (2.1 × 100 mm, 3.5 μm) with a linear gradient elution of acetonitrile/water. The proposed method was applied to analyze 15 batches of samples with acceptable linearity (r2, 0.9923–0.9992), precisions (RSD, 1.0–3.0%), repeatability (RSD, 2.0–3.2%), stability (RSD, 2.2–3.2%), and recovery (RSD, 2.1–3.6%) of the 13 compounds. These results demonstrated that this presented method was effective and reliable for the comprehensive quality evaluation of P. capitatum. Moreover, our study can provide chemical evidence to reveal the material basis of its therapeutic effects.  相似文献   
2.
建立了定量核磁共振波谱法同时测定虎杖中白藜芦醇和虎杖苷的方法。样品用80%乙醇和丙酮两次超声提取净化,再用定量核磁共振波谱法测定。考察了样品预处理和核磁共振实验条件对测定结果的影响,选择氘代二甲亚砜-重水(10∶1,V/V)为溶剂,用基准物质邻苯二甲酸氢钾标定的2,3,5-三碘苯甲酸为内标,选择脉冲延迟时间为5 s,采样次数为32次。定量峰为6.388~6.391(白藜芦醇:H-2,6,d,2H)和6.322~6.330(虎杖苷:H-4,t,1H)。结果表明,NMR测定的精密度均小于0.6%,线性相关系数(r)均大于0.999,白藜芦醇和虎杖苷的检出限分别为0.23和0.24 g/L,定量限分别为0.69和1.57 g/L,包括样品提取过程的回收率分别为97.7%~103.5%(RSD=2.4%)和94.5%~99.2%(RSD=1.6%),显示出定量核磁共振法在中药定量时的可靠性。实际测定4种虎杖饮片及配方颗粒样品中白藜芦醇和虎杖苷含量分别为3.57~5.69 mg/g和12.73~24.07 mg/g。  相似文献   
3.
Polygonum capitatum is widely used in southwest China. It has considerable therapeutic efficacy for urinary tract infections. P. capitatum contains multiple components and quality assessment can be achieved by means of metabolic fingerprinting. In this paper, a new strategy for P. capitatum quality determination was developed. Eleven batches of P. capitatum were collected from five geographical areas in China including a standard batch regulated by Good Agriculture Practice. Gas chromatography with mass spectrometry was used to generate fingerprints from triplicate extractions to each batch (n = 33). Hierarchical clustering analysis was applied to assess similarities among the ten batches to the standard batches. Orthogonal projection to latent structures discriminate analysis, cross‐validated with permutation tests, was performed to investigate discriminating metabolites. Results demonstrated that the overall evaluation hierarchical clustering analysis clustered two batches with distance > 3. Orthogonal projection to latent structures discriminate analysis (R2Y (cum) = 0.997, Q2 (cum) = 0.97, CV‐ANOVA = 8.48 × 10?11) indicated that several sugars contributed to batch classification. This method is a rational approach that can classify against a regulated plant standard and distinguishes samples from different origins or processing time in a holistic manner and metabolites driving any differences can be easily identified.  相似文献   
4.
Investigation of the roots of Polygonum bistorta L. afforded seven compounds including five triterpenoids, a coumarin, and a steroid, the structures of which were identified by EIMS, 1H NMR, 13C NMR, DEPT, and HMBC experiments. All the compounds have been isolated from Polygonum genus for the first time. Published in Khimiya Prirodnykh Soedinenii, No. 5, pp. 463–465, September–October, 2007.  相似文献   
5.
白藜芦醇的电化学行为及其与DNA的相互作用   总被引:1,自引:0,他引:1  
采用电化学方法研究了白藜芦醇在pH=2~13的缓冲溶液中的电化学行为、抗氧化能力及其与DNA的相互作用. 研究结果表明, 在2.011的溶液中, 白藜芦醇产生的P4和P5波分别是其二价和三价阴离子的还原波. 在最佳实验条件下, 微分脉冲极谱图上IP3在8.0×10-8~2.0×10-6 mol/L范围内与白藜芦醇的浓度呈线性关系, 检出限为4×10-8 mol/L. 将该法用于中药虎杖中白藜芦醇含量的测定, 结果与高效液相色谱法一致.  相似文献   
6.
Three new anthraquinones, emodin-8-β-D-(2"-O-coumarate)glucoside 1, emodin-8-β-D-(6'-O-acetyl)glucoside 2 and physicon-8-β-D-(6'-O-acetyl)glucoside 3, were isolated from the roots of Polygonum cillinerve and their structures were established by spectroscopic methods. The biological activity indicated that compound 1 had the scavenging activity on 1,1-diphenyl-2-picrylhydrazyl (DPPH) radicals (the IC50 = 8.5 μmol/L), and compound 1-3 showed no activities against HL-60 and BCJC-823 cells by MTT method in vitro.  相似文献   
7.
白藜芦醇分子印迹聚合物合成及其对中药虎杖提取液活性成分的分离;分子印迹聚合物;白藜芦醇;虎杖;结合能力;选择性  相似文献   
8.
Rapid, economic, and highly effective determination of multiple mycotoxins in complex matrices has given huge challenges for the analytical method. In this study, an economic analytical strategy based on sensitive and rapid ultrafast liquid chromatography coupled to hybrid triple quadrupole/linear ion trap mass spectrometry technique was developed for the determination of seven mycotoxins of different chemical classes (aflatoxin B1, B2, G1, and G2, ochratoxin A, T‐2 toxin, and HT‐2 toxin) in Polygonum multiflorum. Target mycotoxins were completely extracted using a modified quick, easy, cheap effective, rugged, and safe method without additional clean‐up steps. The types of extraction solvents and adsorbents for the extraction procedure were optimized to achieve high recoveries and reduce coextractives in the final extracts. Due to significant matrix effects for all analytes (≤68.9% and ≥110.0%), matrix‐matched calibration curves were introduced for reliable quantification, exploring excellent linearity for the seven mycotoxins with coefficients of determination >0.9992. The method allowed high sensitivity with limit of detection in the range of 0.031–2.5 μg/kg and limit of quantitation in the range of 0.078–6.25 μg/kg, as well as satisfactory precision with relative standard deviations lower than 8%. Recovery rates were between 74.3 and 119.8% with relative standard deviations below 7.43%. The proposed method was successfully applied for 24 batches of P. multiflorum samples, and six samples were found to be positive with aflatoxin B1, B2, G1, or ochratoxin A. The method with significant advantages, including minimum analytical time, low time and solvent consumption, and high sensitivity, would be a preferred candidate for economic analysis of multiclass mycotoxins in complex matrices.  相似文献   
9.
为有效控制头花蓼重金属污染问题、保障头花蓼药用安全提供科学依据,通过盆栽试验,研究不同浓度锑(Sb)污染土壤中头花蓼(Polygonum capitatum)对Sb的吸收累积特征及头花蓼中Sb对人体的健康风险影响,并预测头花蓼食用量在人体可接受范围内时头花蓼种植土壤中Sb的安全限值。结果表明,随着土壤中Sb含量增加,头花蓼生物量及耐性系数减小,头花蓼各器官Sb含量增加,且表现为根>叶>茎。头花蓼根部、地上部对Sb的富集系数分别为0.53~1.76(平均1.32)、0.13~0.36(平均0.23),且均在土壤中Sb处理量为200 mg/kg时达到最大值;头花蓼对Sb的转运系数为0.13~0.24(平均0.18),表明头花蓼将Sb从根部转运到地上部的能力较低。在Sb浓度低于2.09 mg/kg的土壤中种植头花蓼,头花蓼根、茎、叶各部位均可安全食用;但土壤中Sb浓度高于8.72 mg/kg时,头花蓼各部位食用均存在安全风险。  相似文献   
10.
何首乌有生首乌和制首乌之分,生首乌能解毒,润肠通便;制首乌能补肝肾,益精血,乌须发,强筋骨,化浊降脂。生/制首乌都含有二苯乙烯苷类、蒽醌类、磷脂类等化学成分,但其含量存在一定差异。生首乌炮制后其毒性减弱。生/制首乌的功效、主治和毒性都存在一定的差异,在外观性状上差异较易识别,但其磨成粉末后两者不易区分。因此,寻找一种快速简单的判别方法来区分生/制首乌十分必要。中红外光谱法具有检测速度快,对样品无损等优势,已在中药质量控制和鉴别中得到广泛的应用。该研究建立生/制首乌中红外光谱的指纹图谱,并采用正交偏最小二乘-判别分析对其进行鉴别。在4 000~700 cm-1范围内采集38批不同来源生/制首乌中红外光谱数据,分析其主要的特征峰,并用simca13.0软件对数据进行正交偏最小二乘-判别分析。建立38批不同来源生/制首乌中红外指纹图谱,并分析出主要化学成分包括蛋白质类、核酸类、脂肪酸类、蒽醌类、二苯乙烯苷类、磷脂类。对红外光谱峰形和峰强度进行分析,生首乌和制首乌的峰形差异比较少,但峰强度具有一定的差异。为了建立生/制首乌红外光谱差异模型,采用正交偏最小二乘-判别分析法,其结果能很好地将生/制首乌分成两类,左边为制首乌,右边为生首乌。根据变量在项目中的重要性(VIP值)筛选差异化学成分,并利用SPSS17.0统计软件进行t检验,以VIP>1及p<0.05确定差异性化学成分。生/制首乌的差异性化学成分为二苯乙烯苷类、蒽醌类、磷脂类,表明何首乌炮制后二苯乙烯苷类、蒽醌类、磷脂类的含量都发生变化。中红外光谱结合模式识别筛选出差异性化学成分和文献报道基本一致,表明此法可用于生/制首乌鉴别。本研究成功采用中红外光谱对生/制首乌进行快速检测和整体质量评价,结合模式识别能将其鉴别,可为中药质量控制和快速鉴别提供依据。  相似文献   
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