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81.
A variety of bioactive substances may account for the recognized efficacy and wide clinical application of Psoraleae Fructus in China. A high‐performance liquid chromatography–diode array detector (HPLC‐DAD) fingerprint method was developed to present the comprehensive phytochemical profile of the crude drug. Thirteen major compounds were separated and identified by HPLC coupled with time‐of‐flight mass spectrometry (HPLC/TOF‐MS), namely psoralenoside (PO), isopsoralenoside (IPO), psoralen (PS), isopsoralen (IPS), neobavaisoflavone (NBF), bavachin (BC), corylin (CN), bavachromene (BCM), psoralidin (PD), isobavachalcone (IBC), bacachinin (BCN), corylifol A (CA) and bakuchiol (BK). Then quantitative analysis of multiple components by single marker (QAMS) was applied in content determination of PO, IPO, PS, IPS, BC, IBC, BCN, CA and BK, with NBF as the internal standard. The calculation results indicated no significant difference from the traditional external standard method (p > 0.05, RSD < 2.62%), suggesting that QAMS is a reliable and convenient method for content determination of multiple chemical compositions, especially when there is a shortage of reference substances. In conclusion, simultaneous qualitative and quantitative analysis of Psoraleae Fructus may be fulfilled through the newly proposed method of QAMS combined with HPLC‐DAD/TOF‐MS fingerprint.  相似文献   
82.
Twenty commercial samples of Aurantii Fructus Immaturus (Poncitrus trifoliata) and 30 of Aurantii Fructus Maturus (Citrus aurantium and C. wilsonii) were collected from the Taiwan and China herbal markets. The contents of 12 constituents in these samples were determined by HPLC and were used to assess the potential relationships with their plant origins. Multivariate analysis including principal component analysis (PCA), cluster analysis (CA), and linear discriminant analysis (LDA) were used as classification procedures. Natural groupings of the samples divided into three sets successfully, 20 P. trifoliata, 15 C. aurantium, and 15 C. wilsonii, were observed by using PCA and CA. The application of LDA gave correct assignation percentages of 100.0% for all three groups.  相似文献   
83.
高效液相色谱-电喷雾质谱法测定枳壳中黄酮苷类化合物   总被引:11,自引:0,他引:11  
利用高效液相色谱与电喷雾质谱联用技术研究了枳壳中的黄酮苷类化合物。实验采用反相C18色谱柱,二元线性梯度洗脱,分离并检测了枳壳中的6种黄酮苷类化合物;它们分别是新圣草苷(neoeriocitrin)、异柚皮苷(isonaringin)、柚皮苷(naringin)、橙皮苷(hesperidin)、新橙皮苷(neohesperidin)和新枸橘苷(neoponcirin);通过与电喷雾质谱联用获得了这6种黄酮苷的准分子离子峰([M+H]^+)及分子加钠峰([M+Na]^+),利用质谱的碰撞诱导解离技术获得了碎片裂解信息。通过这此质谱信息并结合文献,对这6种化合物进行了结构鉴定。  相似文献   
84.
为鉴别补骨脂与其混伪品,对两种种子的可溶性蛋白质进行了聚丙烯酞胺凝胶电泳分析.结果表明,补骨脂及其混伪品的电泳图谱存在显著差异,电泳图谱可作为补骨脂及其混伪品的鉴别依据.  相似文献   
85.
智子颗粒剂降血铅的临床疗效观察   总被引:8,自引:0,他引:8  
应用中药智子颗粒剂(方剂组成:枸杞子,益智仁,煅牡蛎,牛磺酸)预防,治疗铅暴露导致儿童亚临床神经毒性,其方法:在一定区域内对年龄7~12岁小学生共399名进行血铅测定,其中血铅值〉20μg/dL(0.965umol/L)16名,随机分为给药组,对照组各60名,开放组42名,用药前后进行血红蛋白,身长,体重,视力测定,并在给药组中给药前后进行血液生化及免疫学检查(ALT,AstBun,Cr,IgG,  相似文献   
86.
Loganin is an important constituent of the traditional Chinese medicine Fructus Corni, with several bioactivities. Microbial metabolism of loganin by intestinal bacteria was investigated. Two metabolites (log-1 and log-2) were isolated from anaerobic culture and their structures were identified by means of their ESI-MS, (1)H-NMR, (13)C-NMR and 2D-NMR spectral data. Log-1 was an aglycone of loganin and log-2 was proved to be a new compound. In vivo metabolites of loganin were detected in rat urine, bile and feces after oral administration of loganin and the structures were proved to be identical with that of the microbial metabolites log-1 and log-2 by HPLC-PDA analysis and comparison with the reference standards. Therefore we can prepare metabolites by anaerobic culture with intestinal bacteria.  相似文献   
87.
采用傅立叶红外光谱和二阶导数谱分析方法,对药材瓜蒌不同部位(皮、瓤、子)的红外光谱进行分析.红外谱图显示,瓜蒌各部位均含糖及苷;瓜蒌皮和瓜蒌子中含黄酮及酯类成分;瓜蒌瓤和瓜蒌皮中含相当量的淀粉.二阶导数谱中,在1800~700 cm-1区域内,瓜蒌子的谱峰最简单,次之为瓜蒌瓤,全瓜蒌和瓜蒌皮的峰数较多,峰形和峰强比较相...  相似文献   
88.
傅里叶变换红外光谱法应用于中药砂仁真伪鉴别的研究   总被引:10,自引:5,他引:10  
为了直接准确地鉴别砂仁及其伪品的真伪, 采用傅里叶变换红外光谱法直接测定砂仁及其伪品的红外光谱。结果阳春砂、绿壳砂、海南砂的红外光谱差别不大,而砂仁与其伪品红壳砂仁、海南假砂仁、华山姜及山姜的红外光谱吸收差别较大。对同一批次的不同样品进行了重复性试验,二阶导数傅里叶变换红外光谱正峰值的峰位一致率检验结果无显著性差异存在,说明可以采用FTIR法直接、快速、准确地对阳春砂、绿壳砂、海南砂与其伪品红壳砂仁、海南假砂仁、华山姜及山姜进行区别鉴定。  相似文献   
89.
The identification and quantization of traditional Chinese medicine (TCM) are a challenge for researchers and industry. Using untargeted analytical methods, the in vivo detection and identification of TCM compounds are difficult because of the significant interference of endogenous substances. Fortunately, the ongoing development of new analytical technologies, especially Q-Orbitrap–MS, offers some solutions. Our team developed a holistic MS method, combining untargeted data-dependent MS2 (dd-MS2) modes to extensively identify TCM prototypes in vivo. The method was successfully applied to the analysis of Ligustri Lucidi Fructus (LLF). LLF is a widely used TCM with a remarkable nourishing effect on the liver and kidney. In the study, we aimed to identify the prototypes in rat plasma after oral administration of LLF extract. Following separation on an HSS T3 column, LLF extract and rat plasma were performed in untargeted dd-MS2 mode. Forty-seven compounds were characterized in rats plasma as prototypes of LLF extract. Furthermore, seven major prototypes were chosen as pharmacokinetic markers to investigate LLF's pharmacokinetic properties. The results provides comprehensive determination of compounds in LLF both in vitro and in vivo, which is important for quality control, pharmacology studies and clinical use of LLF.  相似文献   
90.
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