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51.
Three new dammarane‐type triterpenoid saponins, 1 – 3 , were isolated and identified as (20S)‐20‐O‐[β‐D ‐xylopyranosyl‐(1→6)‐β‐D ‐glucopyranosyl‐(1→6)‐β‐D ‐glucopyranosyl]dammar‐24‐ene‐3β,6α,12β, 20‐tetrol ( 1 ), (20S)‐6‐O‐[(E)‐but‐2‐enoyl‐(1→6)‐β‐D ‐glucopyranosyl]dammar‐24‐ene‐3β,6α,12β,20‐tetrol ( 2 ), and (20S)‐6‐O‐[β‐D ‐xylopyranosyl‐(1→2)‐β‐D ‐xylopyranosyl]dammar‐24‐ene‐3β,6α,12β,20‐tetrol ( 3 ) from the roots of Panax notoginseng (Burkill ) F.H.Chen (Araliaceae). Their structures were elucidated on the basis of spectroscopic analyses, including 1D‐ and 2D‐NMR techniques and HR‐ESI‐MS, as well as by acidic hydrolysis.  相似文献   
52.
Microwave-assisted extraction of ginsenosides from ginseng root   总被引:2,自引:0,他引:2  
The extractions of ginsenosides Rg1 and Rb1 from ginseng root under atmospheric pressure by focused microwave-assisted technique have been investigated. The parameters used for the optimization were solvent composition, extraction time, and applied microwave power. The ginsenosides were quantified by high-performance liquid chromatography equipped with UV/Vis detector. The results of the 15-min microwave-assisted extraction (0.28% of Rg1 obtained in 70% water-ethanol and 1.31% of Rb1 obtained in 30% water-ethanol under 150 W of microwave power) were better than that from 10-h conventional solvent extraction (0.22% of Rg1 and 0.87% of Rb1 obtained in 70% water-ethanol).  相似文献   
53.
A reversed-phase liquid chromatographic method was used to determine the ginsenosides Rg1, Rb1 and Rd of Panax notoginseng in rat tissues (kidney, liver, heart, spleen and lung) after the administration of total saponins of P. notoginseng. The tissue samples were treated with solid-phase extraction prior to HPLC. The calibration curves for the three saponins were linear in the given concentration ranges. The intra-day and inter-day assay coefficients in tissues were between 76 and 120% respectively. The recoveries of all the tissues were higher than 70%. This method was applied to evaluate the distribution of the three major saponins of P. notoginseng in rat tissues.  相似文献   
54.
微波水解衍生高效液相色谱法测定西洋参中的氨基酸   总被引:3,自引:0,他引:3  
用微波辅助提取酸水解西洋参中的蛋白质, 对生成的氨基酸进行微波衍生后用高效液相色谱法进行测定.对微波衍生条件和微波水解的条件进行了优化.研究结果表明, 190 ℃, 15 min微波水解得到氨基酸的产率与传统加热水解(110 ℃, 24 h)的结果基本相同.用2,4-二硝基氟苯(DNFB)对氨基酸进行微波衍生, 氨基酸在微波衍生时间大于20 s时, 衍生反应基本完全; 而传统DNFB衍生需在60 ℃水浴加热1 h, 所以微波衍生法明显缩短了氨基酸分析时间.用高效液相色谱法对西洋参根中的氨基酸进行了测定, 结果令人满意.  相似文献   
55.
20 (R)和 2 0 (S) 人参皂甙 Rg2 属于达玛烷型四环三萜类化合物 .应用 2DNMR技术 :1 H 1 HCOSY、HMQC和HMBC全归属 2 0 (R)和 2 0 (S) 人参皂甙 Rg2 碳和氢质子信号 ,为该类型化合物的结构鉴定提供波谱学依据 .  相似文献   
56.
不同产地对中药次生代谢产物有显著影响,产地鉴别有助于中药的科学合理利用;其次,有效成分含量检测是评价中药质量的主要手段。通过傅里叶变换红外光谱结合化学计量学建立快速鉴别三七产地及测定三七中四种主要皂苷的方法,为三七的科学、合理、规范使用以及对三七质量进行快速评价提供依据。采集5个区域12个产地117个三七样本的红外光谱。产地鉴别预处理数据采用离散小波变换除去噪音造成的部分高频信号,偏最小二乘判别对产地判别贡献率大于1的数据进行筛选,kennard-stone算法将117个个体分为70%训练集与30%预测集。训练集数据用于建立支持向量机判别模型,交叉验证法用于筛选支持向量机最优参数,预测集数据对支持向量机判别模型结果进行验证。皂苷含量预测预处理数据采用标准正态变量变换、离散小波变换处理;处理的红外数据设为X变量,三七样品中通过高效液相色谱法测得的四种皂苷总量设为Y变量,采用正交信号校正去除红外光谱中与四种皂苷总量无关的干扰数据。个体数据分为80%训练集与20%预测集,训练集建立偏最小二乘回归模型,预测集数据对偏最小二乘回归模型的预测结果进行验证。结果显示: (1)交叉验证法得到支持向量机判别模型的最优参数为c=2.828 43,g=0.062 5,训练集的产地判别最优正确率为91.463 4%;(2)支持向量机判别模型参数设置为最优参数,代入预测集数据,预测集的产地判别正确率为94.285 7%,判别正确率较高;(3)训练集建立偏最小二乘回归模型的相关系数R2=0.941 8,校正均方差RMSEE=4.530 7;(4)代入预测集数据,预测集的相关系数R2=0.962 3,外部检验均方差RMSEP=3.855 9,皂苷预测值与高效液相检测值接近,预测效果良好。傅里叶变换红外光谱结合支持向量机能对三七进行产地鉴别,正交信号校正结合偏最小二乘回归能对三七中四种主要皂苷总量进行准确预测,为三七质量控制提供一种快速简便、无损、高灵敏度的检测方法。  相似文献   
57.
A quick, easy, cheap, effective, rugged, and safe extraction approach and gas chromatography/tandem mass spectrometry with programmed temperature vaporization sampling technology were used to determine fungicide quintozene and its hazardous impurity hexachlorobenzene (HCB) in Panax notoginseng root, which is commonly used as a rare traditional Chinese medicine worldwide. The mean recoveries were in the ranges of 94–125 and 84–119% for quintozene and HCB with relative standard deviations of 6.2–16.1% at three concentrations: 0.01, 0.1 and 1 mg kg?1. Heavy metals arsenic, cadmium, copper and lead were simultaneously detected by an inductively coupled plasma–mass spectrometry approach after digestion with nitric acid. The above methods were used to analyze 50 samples of P. notoginseng roots collected at markets and planting bases from the special local producing areas, namely, Honghe, Kunming and Wenshan in Yunnan province, China. Quintozene and HCB in root samples were determined at <0.0015–1.50 and <0.0015–0.125 mg kg?1. In the 50 samples, 28, 16, 56, 6 and 2% exceeded the maximum permissible levels in medicinal plants (WM/T2‐2004) for quintozene, arsenic, cadmium, lead and copper. [Correction added on 28 January 2019, after first online publication: the percentages in the preceding sentence have been corrected]. The results showed that the method is robust and suitable for measuring quintozene, its hazardous impurity and heavy metals in P. notoginseng roots.  相似文献   
58.
赵楠  程孟春  吴玉林  刘丹  张晓哲 《色谱》2019,37(12):1305-1313
采用基于超高效液相色谱-高分辨质谱的多肽组学技术对人参主根、支根、须根和芦头的多肽谱进行全面分析,旨在评价人参不同形态区域多肽表达的异同。本研究共表征62个数据库中已收录的人参多肽。结果表明,人参不同部位均富含多肽类成分。多肽组学研究发现,人参主根和支根、芦头与须根之间多肽含量具有显著差异,从鉴定到的多肽中共发现25个稳定表达的已知潜在多肽标志物。其中多肽种类及含量在主根与其他部位间差异最显著,为主根与非主根药效差异研究提供了新思路。本研究揭示了人参多肽结构多样性及人参不同部位人参多肽表达的异同,对人参化学特征评价具有重要意义,为人参质量控制和合理应用提供了化学依据。  相似文献   
59.
Panax ginseng is widely consumed as a functional food in the form of tea, powder, capsules, among others, and possesses a range of pharmacological activities including adaptogenic, immune‐modulatory, anti‐tumor, anti‐aging and anti‐inflammatory effects. The aim of this study was to identify and quantify the major ginsenosides and their metabolites in rat plasma, urine and feces after administration of P. ginseng extract using LC–MS/MS. We collected rat plasma samples at 0.5, 1, 2, 4, 8, 12, 24 and 48 h, and the amounts of urine and fecal samples accumulated in 24 h. Fourteen major ginsenosides and their metabolites were observed in fecal samples at high levels; however, low levels of 11 ginsenosides were detected in urine samples. The pharmacokinetics of the major ginsenosides and their metabolites was investigated in plasma. The results indicated that the maximum plasma concentration, time to maximum concentration and area under the curve of compound K were significantly greater than those of other ginsenosides. This study thus provides valuable information for drug development and clinical application of P. ginseng.  相似文献   
60.
The Caco-2 cells have been recognized as effective tools to be applied to imitate the drug absorption in human intestine for the transport of drug. In this study, Caco-2 cell monolayer model was used to study compatibility of the transport of the Veratrum alkaloids in different proportions with Panax ginseng. A specific ultra-high performance liquid chromatographic-electrospray ionization-mass spectrometric (UPLC-ESI-MS) method is developed for the semi-quantitative determination of Veratrum alkaloids on intestinal transport with berberine as internal standard (IS). In the Caco-2 model constructed, three influencing factors are investigated, including time, concentration and recovery rates of the Veratrum alkaloids during the uptake from AP (apical side) to BL (basolateral side). The results suggest that the flux of Veratrum alkaloids is time dependent and concentration dependent. And the absorption of all eight Veratrum alkaloids increase after compatibility with Panax ginseng compared to the single Veratrum nigrum extraction. This research was studied from the perspective of intestinal absorption by the UPLCESI-MSmethod. Thismethod was successfully applied to transport studies of the Veratrum alkaloids and the interaction mechanism between Veratrum nigrum and Panax ginseng.  相似文献   
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