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141.
Simultaneous detection of eight active components in Radix Tinosporae by ultra high performance liquid chromatography coupled with electrospray tandem mass spectrometry 下载免费PDF全文
A rapid and sensitive ultra high performance liquid chromatography with electrospray ionization tandem mass spectrometry method was developed and validated for the simultaneous determination of eight major active components (magnoflorine, menisperine, 20‐hydroxyecdysone, cepharanthine, columbamine, jatrorrhizine, columbin, and palmatine) in Radix Tinosporae. The separation was performed on an InterSustainSwift C18 column (1.9 μm, 2.1 id × 100 mm) at 40 °C with a gradient elution. A mixture of acetonitrile and methanol (v/v = 1:1) and ammonium acetate buffer (25 mmol/L ammonium acetate with 0.2% formic acid) were used as mobile phases, and the flow rate was set at 0.4 mL/min. The recovery was tested in real samples and calculated to be 86.97–111.28%, and all the compounds showed good linearity (r > 0.998) in relatively wide concentration ranges. The developed method was applied to the determination of eight active compounds in real herb samples, which were collected from four different places. It has been demonstrated that the proposed method has great potential for the quality control of the traditional Chinese medicine Radix Tinosporae. 相似文献
142.
Determination of nine active components in Radix Hedysari and Radix Astragali using capillary HPLC with diode array detection and MS detection 总被引:1,自引:0,他引:1
A capillary HPLC (cHPLC) coupled with diode array detection (DAD) and MS method was developed for the simultaneously qualitative and quantitative determination of nine components, namely vanillic acid, calycosin-7-O-beta-D-glucoside, (6alphaR,11alphaR)-9,10-dimethoxypterocarpan-3-O-beta-D-glucoside, ononin, calycosin, (3R)-2'-hydroxy-3',4'-dimethoxyisoflavan-7-O-beta-D-glucoside, isoliquiritigenin, formononetin, (3R)-8,2'-dihydroxy-7,4'-dimethoxyisoflavan, in Radix Hedysari (Hongqi) and Radix Astragali (Huangqi). Simultaneous separation of these nine compounds was achieved on a Zorbax C18 microcolumn (5 microm, 150 x 0.3 mm). The mobile phase consisted of (A) 0.3% aqueous formic acid and (B) ACN with a gradient elution. The identification of nine compounds in both Hongqi and Huangqi was confirmed by TOF-MS. All calibration curves showed good linearity (R(2) >0.998) within test ranges. This method showed good repeatability for the quantification of these nine components in Hongqi and Huangqi with intra- and inter-day variations of less than 1.89 and 3.13%, respectively. The validated method was successfully applied to quantify nine investigated components in eighteen samples of Hongqi and Huangqi. Hierarchical cluster analysis of 18 samples was performed using the peak area of nine analytes on cHPLC chromatograms. The result showed that Hongqi and Huangqi are significantly different, though the two species of Astragalus are very similar. 相似文献
143.
A comprehensive two-dimensional liquid chromatographic system incorporating a vacuum-evaporation interface was developed. Normal-phase liquid chromatography with a CN microcolumn was used as the first dimension (1(st)-D), and reversed-phase liquid chromatography with a C(18) monolithic column was used as the second dimension (2(nd)-D). An electronically controlled dual-position, ten-port valve with two identical storage loops served as the interface and the analysis time in the 2(nd)-D was 1.5 min. The solvent in the loops of the interface was evaporated at 25 degrees C under vacuum conditions, leaving the analytes on the inner wall of the loops. The mobile phase of the 2(nd)-D dissolved the analytes in the loop and injected them onto the second column, allowing an on-line solvent exchange of the fractions from the 1(st)-D to the 2(nd)-D. The chromatographic resolution of analytes on the two dimensions was evaluated. Sample loss due to evaporation in the interface was investigated with standard samples having different boiling points. The usefulness of the comprehensive 2-DLC system was demonstrated in the analysis of a traditional Chinese medicine Radix salviae miltiorrhiza bage extract. 相似文献
144.
Meiyuan Wang Shuhua Pei Luyao Xie Hanlin Li Shoufang Tang Yuwen Li Ziyi Chen Shu Liu Zhongying Liu 《Journal of separation science》2023,46(21):2300398
Platycodi Radix (PR) is a valuable herb that is widely used in the treatment of chronic obstructive pulmonary disease in clinics. However, the mechanism of action for the treatment of chronic obstructive pulmonary disease remains unclear due to the lack of in vivo studies. Our study established a novel integrated strategy based on ultra-performance liquid chromatography coupled with time-of-flight mass spectrometry, network pharmacology, and molecular docking to systematically analyze the tissue distribution and active compounds of PR in vivo and the therapeutic mechanism of chronic obstructive pulmonary disease. First, tissue distribution studies have shown that the lung is the organ with the highest distribution of PR compounds. Subsequently, network pharmacology results showed that the tumor necrosis factor signaling pathway, interleukin-17 signaling pathway, and mitogen-activated protein kinase signaling pathway were the critical mechanisms of PR against chronic obstructive pulmonary disease. Ultimately, molecular docking results showed that the key targets were stably bound to the corresponding active compounds of PR. Our study is of great significance for the screening of the key effective compounds and the study of the mechanism of action in traditional Chinese medicine and provides data to support the further development and utilization of PR. 相似文献
145.
Saposhnikoviae Radix (SR), the dried root of Saposhnikovia divaricata (Turcz.) Schischk. (Umbelliferae), is commonly used as a traditional Chinese medicine. In this study, a rapid and accurate method was firstly, developed for the qualitative analysis of SR by high-performance liquid chromatography coupled with electrospray ionisation quadrupole time-of-flight mass spectrometry (HPLC-ESI-Q-TOF-MS/MS). A total of 45 compounds were identified or tentatively characterised, including 13 chromones, 28 coumarins and four others. Among them, 16 compounds were identified from SR for the first time. In addition, six chromones reference standards, including two isolated compounds of 3′-O-angeloylhamaudol and norcimifugin from the extraction of SR, were used to study the fragmentation pathways of chromones. The developed method was effective for characterising the compounds of SR, and the results of the study enriched the understanding of the chemical connotation. 相似文献
146.
《Biomedical chromatography : BMC》2018,32(6)
Rhizoma et Radix Polygoni Cuspidati (RRPC) is commonly prescribed for the treatment of amenorrhea, arthralgia, jaundice and abscess in traditional Chinese medicine. Previous pharmacological studies have indicated that polyphenols are the main pharmacological active ingredients in RRPC. Meanwhile, the poor bioavailability of polyphenols in RRPC implies that those components are probably metabolized by intestinal bacteria before absorption. However, there is rather limited information about RRPC''s metabolites produced by intestinal bacteria and the intestinal absorbed constituents. In the present study, the metabolites were characterized after the aqueous extract of RRPC was incubated with the crude enzyme of human intestinal bacteria in vitro. The metabolic characteristics of glycosides in RRPC were figured out by comparing the metabolic profiles of emodin‐8‐O‐β‐d ‐glucopyranoside and polydatin between aqueous extract of RRPC and equivalent amounts of these two glycosides. The transitional constituents absorbed into blood were investigated in rats via intraduodental administration and portal vein intubation. A total of 38 prototype components and 43 metabolites were detected and characterized in vivo. The overall results demonstrated that the intestinal bacteria played an important role in the metabolism of RRPC, and the main metabolic pathways were hydrolysis in vitro, glucuronidation and sulfation in vivo. 相似文献
147.
Xiaohuan Li Xinhua Guo Miao Sha Wenyuan Gao Xia Li 《Biomedical chromatography : BMC》2022,36(4):e5319
Nowadays, cultivated variants and adulterants of Astragali Radix (AR) have flooded the market, causing the quality assurance of AR to be challenging. To address this issue, we combined network pharmacology with chromatographic fingerprinting and multicomponent quantitative analysis for the quality evaluation of AR. Specifically, through network pharmacology, a complete understanding of the active components and pharmacological activities of AR was established. In addition, establishing fingerprint profiles and multicomponent quantitation by high-performance liquid chromatography (HPLC) is convenient and comprehensive, and can more fully reflect the overall situation of the distribution of various chemical components. To evaluate and differentiate AR from different origins, hierarchical cluster analysis and principal component analysis were performed. The result showed that AR acts synergistically through multiple targets and pathways. The content of chemical components in AR from different origins varied significantly. Combining network pharmacology and multicomponent quantification results, astragaloside II and IV and formononetin can be used as quality markers for the quality control of AR. This study provides a comprehensive and reliable strategy for the quality evaluation of AR and identifies its quality markers to ensure the quality of the herb. 相似文献
148.
Liu Yang Ajiao Hou Xiaojuan Zhang Jiaxu Zhang Song Wang Jiaojiao Dong Shihao Zhang Hai Jiang Haixue Kuang 《Biomedical chromatography : BMC》2022,36(4):e5339
This study aimed to explore the possible mechanism of Achyranthis Bidentatae Radix for the treatment of osteoporosis using tandem mass tag-based proteomics technique combined with mass spectrometry. Proteomics techniques combined with bioinformatics were used to analyze the biological functions of differentially expressed proteins. In addition, western blotting was performed to verify the expression of related proteins. A total of 3,752 proteins were identifiable by proteomic analysis. Furthermore, 93 differentially expressed proteins were identified, of which 61 were upregulated and 32 were downregulated. Differentially expressed proteins were primarily associated with oxidative phosphorylation (p = 4.8 × 10−4) pathways and involved in transmembrane transport (p = 3.5 × 10−3), exocytic process (p = 1.2 × 10−2), cellular developmental process (p = 1.3 × 10−2), adenosine triphosphate metabolic process (p = 1.0 × 10−2) and other biological processes. Western blotting analysis showed that MT-CYB and NDUFA9 were differentially expressed in the bone microenvironment of rats with osteoporosis. We speculated that they were potential biomarkers linked to osteoporosis. This study employed proteomics to explore the potential therapeutic targets of Achyranthis Bidentatae Radix to treat osteoporosis. This revealed that mitochondria are a new target for the treatment of glucocorticoid-induced osteoporosis. 相似文献
149.
《Journal of separation science》2017,40(6):1254-1265
In this study, we propose an integrated strategy for the efficient identification and quantification of herbal constituents using liquid chromatography with mass spectrometry. First, liquid chromatography with quadrupole time‐of‐flight mass spectrometry was employed for the chemical profiling of herbs, where a targeted following nontargeted approach was developed to detect trace constituents by using structural correlations and extracted ion chromatograms. Next, ion pairs and parameters of MS2 of quadrupole time‐of‐flight mass spectrometry were selected to design multiple reaction monitoring transitions for the identified compounds on liquid chromatography with triple quadrupole mass spectrometry. The relative concentration of each constituent was then calculated using a semiquantitative calibration curve. The proposed strategy was applied in a study of chemical interactions between Glycyrrhizae Radix and Coptidis Rhizoma. A total of 140 compounds were identified or tentatively characterized from the herbs, 132 of which were relatively quantified. The visualized quantitative results clearly showed codecoction produced significant constituent concentration variations especially for those with a low polarity. The case study also indicated that the present methodology could provide a reliable, accurate, and labor‐saving solution for chemical studies of herbal medicines. 相似文献
150.
Wan Sheng CHEN* Wei Dong ZHANG Gen Jing YANG Hai Sheng CHEN Chuan Zhuo QIAO Department of Pharmacognosy School of Pharmacy Second Military Medical University Shanghai 《中国化学快报》2001,(6)
The root tuber of Polygonum multiflorum Thunb. ( Polygonaceae ) (PM ) is a famous Chinese traditional medicine, which has been used to remedy for treatment many diseases such as cardiovascular and aging diseases for long times. When it is used as a tonic drug, PM must be prepared in order to eliminate its side effects, and the preparation is known as Radix Polygoni multiflori Preparata ( PMP )1. Here we report the isolation of 2,3,5,4'-tetrahydroxystilbene-2-O-(2'-O-feruloyl)-(-D-gluco … 相似文献