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1.
用内径为0.53mm的填充毛细管正相液相色谱为第一维,用4.6mm(i.d.)×50mmRP-18e整体柱反相色谱为第二维,建立了定量环一阀切换接口的全二维液相色谱系统(NPLC×RPLC).第一维色谱分离洗脱出的组分交替存储在十通阀上的两个定量环中,同时定量环中前一个组分被转移到第二维进行反相分离.因为第一维的流动相流量仅是第二维的1/500,自然解决了流动相兼容问题.采用芳香族化合物的混合物和中药丹参正己烷提取液对该全二维液相系统的分离能力进行了评价. 相似文献
2.
彭宏宇 《西华师范大学学报(哲学社会科学版)》2005,26(2):203-204
采用紫外分光光度法,苯酚-硫酸显色法,于490nm波长处对川牛膝中多糖的含量进行了测定.该方法简便、快速、准确、灵敏度高,可作为川牛膝质量控制标准. 相似文献
3.
4.
反相高效液相色谱法测定附子有效成分含量的方法研究 总被引:7,自引:0,他引:7
运用RP-HPLC测定不同地区附子药材中3种酯型生物碱———新乌头碱、乌头碱和次乌头碱的含量.实验以RP-C18色谱柱为固定相,乙腈-0.1%的乙二胺水溶液为流动相进行梯度洗脱.梯度洗脱程序:乙腈和0.1%的乙二胺水溶液的比率0~17 min为46∶54,17~37 min为82∶18;37~50 min为46∶54,流速为1.0mL/min;紫外检测波长为230 nm.新乌头碱、乌头碱和次乌头碱的标准曲线范围分别是5.62×10-6~5.062×10-5mol/L、2.614×10-6~2.614×10 相似文献
5.
选择生长健壮、无病虫害的附子茎段和顶芽为外植体,接种到附加不同植物生长素的培养基上进行离体培养研究.结果表明:MS+6-BA 2 mg.L-1+NAA 0.3 mg.L-1的培养基诱导无菌苗效果最佳,1/2MS+IBA 1 mg.L-1+KT 0.5 mg.L-1生根培养基,生根率达80%.利用该技术可以成功的建立附子再生植株的实验体系. 相似文献
6.
Jianing Mi Min Zhang Hongyang Zhang Yuerong Wang Shikun Wu Ping Hu 《Journal of separation science》2013,36(3):593-601
A high‐efficient and environmental‐friendly method for the preparation of ginsenosides from Radix Ginseng using the method of coupling of ultrasound‐assisted extraction with expanded bed adsorption is described. Based on the optimal extraction conditions screened by surface response methodology, ginsenosides were extracted and adsorbed, then eluted by the two‐step elution protocol. The comparison results between the coupling of ultrasound‐assisted extraction with expanded bed adsorption method and conventional method showed that the former was better than the latter in both process efficiency and greenness. The process efficiency and energy efficiency of the coupling of ultrasound‐assisted extraction with expanded bed adsorption method rapidly increased by 1.4‐fold and 18.5‐fold of the conventional method, while the environmental cost and CO2 emission of the conventional method were 12.9‐fold and 17.0‐fold of the new method. Furthermore, the theoretical model for the extraction of targets was derived. The results revealed that the theoretical model suitably described the process of preparing ginsenosides by the coupling of ultrasound‐assisted extraction with expanded bed adsorption system. 相似文献
7.
Determination of 12 potential nephrotoxicity biomarkers in rat serum and urine by liquid chromatography with mass spectrometry and its application to renal failure induced by Semen Strychni
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Liqiang Gu Xiaofan Wang Yuanyuan Zhang Yu Jiang Huan Lu Kaishun Bi Xiaohui Chen 《Journal of separation science》2014,37(9-10):1058-1066
In previous nephrotoxicity metabonomic studies, several potential biomarkers were found and evaluated. To investigate the relationship between the nephrotoxicity biomarkers and the therapeutic role of Radix Glycyrrhizae extract on Semen Strychni‐induced renal failure, 12 typical biomarkers are selected and a simple LC–MS method has been developed and validated. Citric acid, guanidinosuccinic acid, taurine, guanidinoacetic acid, uric acid, creatinine, hippuric acid, xanthurenic acid, kynurenic acid, 3‐indoxyl sulfate, indole‐3‐acetic acid, and phenaceturic acid were separated by a Phenomenex Luna C18 column and a methanol/water (5 mM ammonium acetate) gradient program with a runtime of 20 min. The prepared calibration curves showed good linearity with regression coefficients all above 0.9913. The absolute recoveries of analytes from serum and urine were all more than 70.4%. With the developed method, analytes were successfully determined in serum and urine samples within 52 days. Results showed that guanidinosuccinic acid, guanidinoacetic acid, 3‐indoxyl sulfate, and indole‐3‐acetic acid (only in urine) were more sensitive than the conventional renal function markers in evaluating the therapeutic role of Radix Glycyrrhizae extract on Semen Strychni‐induced renal failure. The method could be further used in predicting and monitoring renal failure cause by other reasons in the following researches. 相似文献
8.
High‐expression β1 adrenergic receptor/cell membrane chromatography method based on a target receptor to screen active ingredients from traditional Chinese medicines
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Yuan Yue Hui Xue Xin Wang Qian Yang Yanhong Song Xiaoni Li 《Journal of separation science》2014,37(3):244-249
β‐Adrenergic receptors are important targets for drug discovery. We have developed a new β1‐adrenergic receptor cell membrane chromatography (β1AR‐CMC) with offline ultra‐performance LC (UPLC) and MS method for screening active ingredients from traditional Chinese medicines. In this study, Chinese hamster ovary‐S cells with high β1AR expression levels were established and used to prepare a cell membrane stationary phase in a β1AR‐CMC model. The retention fractions were separated and identified by the UPLC–MS system. The screening results found that isoimperatorin from Rhizoma et Radix Notopterygii was the targeted component that could act on β1AR in similar manner of metoprolol as a control drug. In addition, the biological effects of active component were also investigated in order to search for a new type of β1AR antagonist. It will be a useful method for drug discovery as a leading compound resource. 相似文献
9.
黄连与甘草化学成分的相互作用研究之一——混浊汤剂中沉淀部分的成分研究 总被引:1,自引:0,他引:1
以黄连与甘草为配伍组成的复方是一种沉淀性配伍, 它属于仲景古方系列之一。其汤剂呈混浊状, 分别对离心分离后的溶液与沉淀物的成分进行研究。运用高效液相色谱(HPLC)、傅里叶变换红外光谱(FTIR)和飞行时间质谱(TOF-MS)的方法, 对单煎黄连、单煎甘草和混煎黄连与甘草的溶液和沉淀物的结构组成进行研究。文章着重报道沉淀物成分的研究, 同时还将混煎沉淀物和溶液的谱学行为做了比较。结果发现, 在混煎黄连与甘草的沉淀物中, 黄连的有些化学成分被保留下来, 有些成分却被抑制了;而甘草的化学成分基本都消失了;同时在混煎黄连与甘草的沉淀物中还产生了在单煎黄连与单煎甘草中所没有的一些新物质。此结果说明黄连与甘草在混煎后其沉淀物的结构组成发生了变化, 这是由于在此复方中发生了甘草与黄连化学成分的相互作用所致。根据飞行时间质谱的数据, 推测黄连与甘草发生的化学反应可能有加成反应、分解反应和缔合反应等类型。它表明甘草在此复方中起到了极为重要的作用。通过混煎沉淀物与溶液的研究结果比较还表明, 在沉淀物中可能含有比溶液中更多的化学活性成分,它为古方的药用和疗效提供了一定科学依据。 相似文献
10.
Xue Hua Hui-Jie Hong Dai-Yan Zhang Qiao Liu Fong Leong Qi Yang Yuan-Jia Hu Xiao-Jia Chen 《Molecules (Basel, Switzerland)》2022,27(4)
In this study, a high-performance thin layer chromatography (HPTLC) method by two step gradient elution with two mobile phases was developed for the simultaneous analysis of seven constituents in Ophiopogonis Radix. The chromatography was performed on silica gel 60 F254 plate with dichloromethane-methanol-ethyl acetate-water (70:25:12:3, v/v/v/v) and dichloromethane-methanol (300:1, v/v) as the mobile phase for two step gradient elution. Then, the HPTLC profiles were observed after derivatization with 10% sulfuric acid in ethanol solution. The obtained HPTLC images were further analyzed by chemometric approaches and the samples could be clustered based on regions and/or growth years, which were two important factors affecting the constituents in Ophiopogonis Radix. Furthermore, five compounds including ophiopogonin D, ophiopojaponin C, ophiopogonin D’, ophiopogonin C’ and methylophiopogonanone B were screened as potential lipase inhibitors from Ophiopogonis Radix by the HPTLC-bioautographic method. The binding modes and interactions between the five compounds and lipase were further explored by molecular docking analysis. The developed HPTLC method could be used for quality control of Ophiopogonis Radix and screening of the potential lipase inhibitors. 相似文献