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1.
麻黄中伪麻黄碱在小鼠组织中的分布研究   总被引:1,自引:0,他引:1  
为了解麻黄(Herba ephedrae,简称HE)中伪麻黄碱(Pseudoephedrine,简称PE)在小鼠脑、肺、心、肝、肾的分布变化,探讨HE的归经,用GC-MS/SIM法,分析了用药后30、60、120 min PE在小鼠脏器分布量。结果表明,PE于不同时间点在小鼠脏器的分布由多到少的顺序是:30 min时,肺脏(肾脏、肝脏、脑),心脏;60 min时,肾脏,心脏(肝脏),脑,肺脏;120 min时,脑,肾脏,心脏,肝脏(肺脏)。本试验从PE在小鼠体内脏器的分布量初步反映了HE的归经趋势。  相似文献   
2.
淫羊藿根与叶活性成分的分析和比较   总被引:8,自引:0,他引:8  
采用细胞膜色谱法(CMC)筛选,并结合离体药理实验确定主要活性成分,利用高效液相色谱法分析比较了淫羊藿根与叶中的活性成分及其差异性.色谱条件为Kromasil ODS 柱(150 mm× 4.6 mm.I.D )流动相甲醇-水(70:30,V:V);检测波长270nm。筛选发现淫羊藿根中的两个有效成分YYH-214和YYH-216对血管有较强的舒张作用,表明活性成分在CMC模型体系中的保留特性与药理作用之间存在良好的相关性。在此色谱条件下淫羊藿叶未检测到这两种活性成分.  相似文献   
3.
A high-performance capillary electrophoresis with electrochemical detection (CE-ED) method has been employed for the determination of six bioactive ingredients in traditional Chinese herbs, Herba cepbalanoplosis segeti and Herba cirsii japonici. The effects of several factors such as the acidity and concentration of running buffer, the separation voltage, the applied potential and the injection time on CE-ED were investigated. Under the optimum conditions, the six analytes could be well separated within 21 min in a 75 cm length capillary at the separation voltage of 15 kV in a 50 mmol L–1 borax running buffer (pH 8.4). A 300 m diameter carbon disk electrode was used as the working electrode positioned carefully opposite the outlet of the capillary in a wall-jet configuration at potential of +950 mV (vs. SCE). Good linear relationship was established between peak current and concentration of analytes over two orders of magnitude with detection limits (S/N=3) ranged from 1.5×10–7 to 6.0×10–7 g mL–1 for all six analytes. This proposed method has been successfully applied for the analysis of traditional Chinese herbs after a relatively simple extraction procedure, further on, for the differentiation of these above two seemingly identical herbs based on their electropherograms or characteristic electrochemical profiles.  相似文献   
4.
As a representative of traditionally fermented Chinese medicine, Massa Medicata Fermentata (MMF) shows the functions of invigorating the spleen and stomach and promoting digestion, which plays an important role in the treatment of gastrointestinal diseases. The fermentation mechanism and the key factors that affect the quality of MMF have not been revealed yet, which has become an urgent issue that limits its clinical application. This article aims to systematically and comprehensively reveal the transformation of physical properties and the dynamic trend of chemical components including substrate components, volatile components, and lactic acid as anaerobic fermentation product during MMF fermentation. Along with obvious hyphae growth observed for MMF, the weight of MMF decreased, and the moisture and temperature increased. Through the quantified 14 components from substrate, ferulic acid increased from 45.53 ± 6.94 to 141.89 ± 78.40 μg/g, while glycosides and phenolic acids declined except caffeic acid. Also, within the 66 volatile components analyzed, alcohols and acids increased, while aldehydes and ketones decreased. Lactic acid was not detected in the fermentation substrate, but an apparent increase in lactic acid content was observed along with the increased fermentation days, resulting in 2.54 ± 0.15 mg/g on day 8. Based on the tested components, the fermentation process of MMF was discriminated into three distinct stages by principal component analysis, and an optimal fermentation time of four days was proposed. The results of this study will be of great significance to clarify the characteristics of fermentation and conduce to improving quality standards of MMF.  相似文献   
5.
In this study, a fingerprint-activity relationship modeling between chemical fingerprints and antirheumatic activity was established, and multivariate statistical analysis was used to evaluate the quality of Taxilli Herba (TH) from different hosts. Characteristic fingerprints of 20 batches of TH samples were generated by high-performance liquid chromatography coupled with triple quadrupole-time of flight tandem mass spectrometry (HPLC-Triple TOF-MS/MS), and the similarity analysis was calculated based on thirteen common characteristic peaks by hierarchical clustering analysis (HCA). Subsequently, nine efficacy markers were discovered by combining fingerprints and antirheumatic activity through grey correlation analysis (GCA) and bivariate correlation analysis (BCA). Meanwhile, the content of 5 constituents in 9 markers was determined by high-performance liquid chromatography coupled with triple quadrupole-linear ion trap tandem mass spectrometry (HPLC-QTRAP-MS/MS). The comprehensive quality of TH was assessed using multivariate statistical analysis, including principal components analysis (PCA) and technique for order preference by similarity to ideal solution (TOPSIS). The results showed that a high dose of TH extract could markedly ameliorate arthritis damage compared to other doses, with flavonoids playing an important role in the antirheumatic activity. The comprehensive quality of samples from Morus alba L. (SS) was superior to those from Liquidambar formosana Hance (FXS). The present study will demonstrate the markers associated with efficacy, and provide an applicable strategy for more comprehensive quality control and evaluation of TH.  相似文献   
6.
Glechomae Herba (GH) is rich in bioactive phenolic constituents and is widely used for treatment of cholelithiasis, urolithiasis and dropsy. The simultaneous determination of phenolic constituents in GH from different geographical origins is significant for authentication and quality control purposes. In this study, we developed a strategy integrating targeted analysis and chemometric methods for quality evaluation and discrimination of GH from different geographical origins. Firstly, an accurate and reliable liquid chromatography–tandem mass spectrometry method was developed for simultaneous quantification of 15 phenolic constituents in GH from different geographical origins. The established method was well validated in terms of desirable specificity, linearity, precision and accuracy. Secondly, the quantitative data were subjected to principal component analysis and orthogonal partial least squares discriminant analysis. Thirdly, a heatmap visualization was employed for clarifying the distribution of 15 phenolic compounds in GH from different geographical origins. These results indicated that GH samples from Shandong province obviously differ from those from other provinces in the content of bioactive phenolic constituents. Collectively, the proposed platform might be a suitable tool for quality evaluation and discrimination of GH from different geographical origins, providing promising perspectives in tracking the formulation processes of traditional Chinese medicine products.  相似文献   
7.
Phytochemical investigation on the n-BuOH-soluble fraction of the aerial parts of Epimedium koreanum using the PCSK9 mRNA monitoring assay led to the identification of four previously undescribed acylated flavonoid glycosides and 18 known compounds. The structures of new compounds were elucidated by NMR, MS, and other chemical methods. All isolated compounds were tested for their inhibitory activity against PCSK9 mRNA expression in HepG2 cells. Of the isolates, compounds 6, 7, 10, 15, and 17–22 were found to significantly inhibit PCSK9 mRNA expression. In particular, compound 7 was shown to increase LDLR mRNA expression. Thus, compound 7 may potentially increase LDL uptake and lower cholesterol levels in the blood.  相似文献   
8.
肉苁蓉挥发性化学成分分析   总被引:10,自引:3,他引:10  
报道了用同时蒸馏—萃取法提取肉苁蓉挥发性物质,测得肉苁蓉挥发油的含量为3.5%;利用GC/MS法分离确认出24种化学成分;用峰面积归一化法得出各化学成分在挥发油中的相对百分含量,其中主要成分为丁香酚,占总挥发油的83.60%;又用单离子法分离出丁香酚,并用IR,EI-MS法对其进行分析确认。  相似文献   
9.
超临界CO2萃取与水蒸气蒸馏法研究泽兰中挥发性有机物   总被引:1,自引:0,他引:1  
以超临界CO2萃取法(SFE)提取中药泽兰中的挥发性有机物,经气相色谱-质谱联用(GC-MS)分析,人工解析质谱图及计算机谱库检索相结合进行化学成分结构鉴定,用面积归一化法计算各组分的相对含量。SFE法提取的产率为0.78%,共鉴定75种挥发性化合物,主要成分为植醇、石竹烯氧化物、十六酸、亚油酸、葎草烯等,比文献报道的该挥发油成分多且含量差异较大,其中松香芹醇、蒲勒烯、马鞭烯酮、香芹酮、十六酸、亚油酸、葎草烯、十六酸乙酯、亚麻酸等多种成分未见报道。与水蒸气蒸馏法(SD)提取的泽兰挥发油进行比较,后者提取的产率为0.12%,从中鉴定出50种化合物,主要成分为石竹烯氧化物、柠檬烯、α-蒎烯、葎草烯、月桂烯等。SFE与SD得到的成分仅有31种相同,其它各不相同。  相似文献   
10.
建立了反相离子对色谱法同时测定万乳康样品中淫羊藿苷和盐酸左旋咪唑的含量。本法使用Shim-pack VP-ODS色谱柱(250×4.6 mm,5μm),该流动相为65%甲醇(V/V),10.0 mmol/L的十二烷基磺酸钠,pH=3.0;等度洗脱样品中的淫羊藿苷和盐酸左旋咪唑。紫外检测波长270 nm。结果表明:淫羊藿苷测定的线性范围为2.73~54.58μg/mL,加标回收率为99.45%~100.69%,理论塔板数达6 641;盐酸左旋咪唑测定的线性范围为26.23~524.54μg/mL,加标回收率为99.58%~100.23%,理论塔板数5 564。该方法可用于淫羊藿提取物和万乳康样品中的淫羊藿苷和盐酸左旋咪唑的测定。  相似文献   
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