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41.
A simple, specific and sensitive method for quantitative determination of icariin in rat plasma using reverse-phase high-performance liquid chromatography with UV-detection was developed and applied to an animal study of a lipid-based suspension of the Epimedium koreanum extract in rats. Rutin was selected as the internal standard and methanol was found to be the best solvent for extraction of icariin from the plasma. Linearity was observed between 0.030 and 100 microg/mL (r > 0.99). The extraction recoveries of icariin and rutin were approximately 75 and 80%, respectively, in plasma. The intra- and inter-day coefficients of variation were less than 5%. The limit of detection was 6 ng/mL and the limit of quantification was 18 ng/mL.  相似文献   
42.
淫羊藿炮制前后UPLC-PDA-MS 的指纹图谱研究   总被引:2,自引:0,他引:2  
建立了朝鲜淫羊藿和柔毛淫羊藿药材的超高效液相色谱(UPLC)指纹图谱分析方法, 实验结果表明, 两个品种的指纹图谱差别较大, 朝鲜淫羊藿标出35 个共有峰, 质谱鉴定了26 个峰, 柔毛淫羊藿标出13 个共有峰, 质谱鉴定了9个峰; 研究了朝鲜淫羊藿和柔毛淫羊藿炮制前后UPLC 指纹图谱的变化规律, 指纹图谱发生了五处变化. 该法快速、简便, 重现性好, 从整体上显示淫羊藿药材和炮制品的特征, 为淫羊藿的生品和炮制品的质量控制提供了有效手段.  相似文献   
43.
In the present paper is reported the metnocl for the isolation and extraction of total flavonoids of Epimedium Koreanum Nateai by means of supercritical fluid extraction(SFE). By examining pressure, temperature, amounts of modifier and extraction time, the optimized condition of SFE is confirmed as 30 MPa and 60℃, with 70% ethanol as the modifier. The samples were statically extracted for 30 min, followed bydynamic extraction for 120 min at a flow rate of 6 mL/min. The quantitative analysis of total flavonoids was performed by UV-Vis spectrophotometry. Compared with the conventional method, the SFE method is more efficient, more rapid and more friendly environmentally.  相似文献   
44.
The bioassay-oriented fractionation of mistletoe crude extracts (MCEE) using 75% ethanol and culture products of mistletoe transformed by Rhodobacter sphaeroides, a photosynthetic bacterium (PSBT), revealed that the high cytotoxic activities were due to the petroleum ether extracts (PEs) and the acid-precipitated proteins from the aqueous extracts (AQs) of MCEE and PSBT. The isolated triterpenes may account for the activities of the PEs of MCEE and PSBT, respectively. Extraction of MCEE using petroleum ether led to the isolation of 3-epi-betulinic acid (1), betulonic acid (2), oleanolic acid (3), and β-amyrin acetate (4), while petroleum ether extraction of PSBT led to the isolation of 1,3,4,betulinic acid (5), erythrodiol (6), and (3β)-olean-12-ene-3,23-diol (7). The PE of PSBT exerted higher cytotoxicity than the PE of MCEE, which was due to the different triterpene contents of these two extracts. The cytotoxic activities of all compounds were tested, and the results revealed that compounds 1, 2, 3, 5, 6, and 7 contributed significantly to the cytotoxicities of both PEs. The AQ of the PSBT exerted almost the same cytotoxic activity and lower toxicity compared to the AQ of the MCEE. These findings indicate that mistletoe products biotransformed by R. sphaeroides could be used to treat cancers, since they have lower toxicities and higher antitumor activities compared to standard treatments.  相似文献   
45.
A reliable and comprehensive method for identifying the origin and assessing the quality of Epimedium has been developed. The method is based on analysis of HPLC fingerprints, combined with similarity analysis, hierarchical cluster analysis (HCA), principal component analysis (PCA) and multi‐ingredient quantitative analysis. Nineteen batches of Epimedium , collected from different areas in the western regions of China, were used to establish the fingerprints and 18 peaks were selected for the analysis. Similarity analysis, HCA and PCA all classified the 19 areas into three groups. Simultaneous quantification of the five major bioactive ingredients in the Epimedium samples was also carried out to confirm the consistency of the quality tests. These methods were successfully used to identify the geographical origin of the Epimedium samples and to evaluate their quality.  相似文献   
46.
Edgeworthia tomentosa (Thunb.) Nakai belongs to Thymelaeaceae family, its alabastrum is used as the traditional Chinese medicine ‘Buddleja Officinalis Maxim’. The present study was to elucidate the ultrastructure characteristics of the flower, the phytochemical composition of the aroma essential oils (EOs) and the relevant antimicrobial properties. There were exclusive characters of calyx, ovule, anther and pollen grain of the flowers under scanning electron microscopy. A total of 40 phytochemical components representing 98% of the EOs were successfully identified: monoterpenes and sesquiterpenes were the dominant terpenoids according to Kovats retention index and MS database. EOs exhibited a broad spectrum antimicrobial activity against Gram-positive and Gram-negative bacteria, the best bacteriostatic effect was against Diplococcus pneumonia with MIC and MBC values ranging between 7.8 and 62.5 and 26.0–71.0 μg/mL, respectively. These results demonstrate that the surface microscopic morphological characteristics of Edgeworthia chrysantha Lindl. flowers, are full-scale chemical composition and antimicrobial properties of the EOs.  相似文献   
47.
Angelica gigas Nakai root contains decursin which exerts beneficial properties such as anti-amnesic and anti-inflammatory activities. Until now, however, the neuroprotective effects of decursin against transient ischemic injury in the forebrain have been insufficiently investigated. Here, we revealed that post-treatment with decursin and the root extract saved pyramidal neurons in the hippocampus following transient ischemia for 5 min in gerbil forebrain. Through high-performance liquid chromatography, we defined that decursin was contained in the extract as 7.3 ± 0.2%. Based on this, we post-treated with 350 mg/kg of extract, which is the corresponding dosage of 25 mg/kg of decursin that exerted neuroprotection in gerbil hippocampus against the ischemia. In addition, behavioral tests were conducted to evaluate ischemia-induced dysfunctions via tests of spatial memory (by the 8-arm radial maze test) and learning memory (by the passive avoidance test), and post-treatment with the extract and decursin attenuated ischemia-induced memory impairments. Furthermore, we carried out histochemistry, immunohistochemistry, and double immunohistofluorescence. Pyramidal neurons located in the subfield cornu ammonis 1 (CA1) among the hippocampal subfields were dead at 5 days after the ischemia; however, treatment with the extract and decursin saved the pyramidal neurons after ischemia. Immunoglobulin G (IgG, an indicator of extravasation), which is not found in the parenchyma in normal brain tissue, was apparently shown in CA1 parenchyma from 2 days after the ischemia, but IgG leakage was dramatically attenuated in the CA1 parenchyma treated with the extract and decursin. Furthermore, astrocyte endfeet, which are a component of the blood–brain barrier (BBB), were severely damaged at 5 days after the ischemia; however, post-treatment with the extract and decursin dramatically attenuated the damage of the endfeet. In brief, therapeutic treatment of the extract of Angelica gigas Nakai root and decursin after 5 min transient forebrain ischemia protected hippocampal neurons from the ischemia, showing that ischemia-induced BBB leakage and damage of astrocyte endfeet was significantly attenuated by the extract and decursin. Based on these findings, we suggest that Angelica gigas Nakai root containing decursin can be employed as a pharmaceutical composition to develop a therapeutic strategy for brain ischemic injury.  相似文献   
48.
An efficient, feasible enrichment and separation method of epimedins A, B, C and icariin from Herba Epimedii was developed by the combination of microwave-assisted extraction, macroporous resins and preparative HPLC. WDX-5 macroporous resin shows better recoveries at 96.2%, 97.0%, 98.2% and 97.1% for epimedins A, B, C and icariin than other macroporous resins used in the experiments. As a result, epimedins A (5.1 mg), B (15.3 mg), C (7.6 mg) and icariin (14.3 mg) were obtained from 6.0 g crude Herba Epimedii with the recoveries at 70.8%, 68.9%, 66.7% and 95.3%, respectively. The method developed in this study may provide scientific references for the enrichment and separation of flavonoids from Herba Epimedii.  相似文献   
49.
从朝鲜淫羊蕾的地上部分分离得到4个化合物。经化学和光谱方法鉴定它们为:5,7,3'-三羟基-4'-甲氧基-8-异戊烯基黄酮醇-3-O-α-L-鼠李吡喃糖甙(Ⅰ)、IcarisideC1(Ⅱ)、Epimedokoreanoside-Ⅰ(Ⅲ)和Desmethylicaritin(Ⅳ)。其中Ⅰ是未见报道的新化合物,命名为朝藿甙-C;Ⅱ、Ⅲ和Ⅳ首次从该植物中获得。  相似文献   
50.
Epimedium, one of representatives of traditional Chinese herb, is mainly composed of flavones and polysaccharide. It is famous for its antioxidant, antineoplastic and antiaging activities and has been widely used in the field of invigorating kidney and st…  相似文献   
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