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1.
Cinnamaldehyde (CA), an active ingredient isolated from the traditional Chinese medicine Cortex Cinnamomi, has a wide range of bioactivities. To clarify the distribution characteristics of CA, a selective and sensitive method utilizing gas chromatography–mass spetrometry was initially developed for simultaneously determining the concentration of CA and its metabolite cinnamyl alcohol in rat tissues. Selected ion masses of m/z 131, 105 and 92 were chosen, and separation of the analytes was performed on a DB‐5 ms (30 m × 0.25 mm, 0.25 µm, thickness) capillary column by gas chromatography–mass spectrometry. The calibration curves demonstrated good linearity and reproducibility over the range of 20–2000 and 20–4000 ng/mL for various tissue samples. Recoveries ranged from 86.8 to 107.5%, while intra‐ and interday relative standard deviations were all <11.3%. The analysis method was successfully applied in tissue distribution studies for CA and cinnamyl alcohol. As CA and cinnamyl alcohol may inter‐convert to one another, simultaneous determination of both analytes provides a comparative and accurate data for tissue study. The concentrations of CA and cinnamyl alcohol remaining in spleen were the highest among the main organs, including heart, liver, spleen, lung, kidney and brain. In addition, there was no long‐term accumulation of CA in rat tissues. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
2.
Chemical examination of the fermentation broth of the marine-derived bacterium Bacillus sp. resulted in the isolation of seven new amicoumacin-type isocoumarin derivatives, namely bacillcoumacins A–G (17), together with four known analogues. Their structures were elucidated on the basis of extensive spectroscopic analysis, while the absolute configurations of the new compounds were determined by CD, Mosher’s method, and chemical conversion. Compounds 7 and 9 showed inhibitory effects against the NO production induced by lipopolysaccharide (LPS) in mouse macrophage RAW 264.7 cells.  相似文献   
3.
Chemical investigation of the gorgonian coral Junceella fragilis resulted in the isolation of a new norditerpenoid fragilolide A (1), sixteen new briarane diterpenoids fragilolides B-Q (2–17), together with frajunolides H and N, and three known norcembranoids scabrolide D, sinuleptolide and 5-epi-sinuleptolide. The structures of new compounds were determined on the basis of extensive spectroscopic analysis, including the experimental and calculated ECD data and single-crystal X-ray diffraction for the configurational assignments. The structure of fragilolide A featured an unprecedented 4,13- and 7,11-fused tetracyclic norcembranoid, while the biogenetic relationships of the briarane analogues were postulated. Frajunolide H exerted significant inhibition against a panel of tumor cell lines, and six briarane diterpenoids (3, 6, 8, 12, 16, and frajunolide N) exhibited the inhibitory effects against the HBeAg express of hepatitis B virus in HepAD38 cells. In addition, sinuleptolide and 5-epi-sinuleptolide exerted the effects to inhibit NO production in RAW264.7 macrophage cells, in addition to the activation of ARE and the inhibition of NF-κB expression.  相似文献   
4.
LC Tissue Distribution Study of Paeonol in Rats after Oral Administration   总被引:1,自引:0,他引:1  
Paeonol, an important constituent of the traditional Chinese medicine Cortex Moutan, has a variety of bioactivity. A simple and sensitive HPLC?CUV method has been developed for analysis of paeonol in different rat tissue (heart, liver, spleen, lung, kidney, and brain). Bio-samples were prepared by simple protein precipitation, and separation of paeonol was achieved on a C18 column with methanol?C2% glacial acetic acid solution 70:30 (v/v) as mobile phase at a flow rate of 1.0 mL min?1. UV detection was at 274 nm and the column temperature was 30 °C. Linearity was good between 0.025 and 5.0 ??g mL?1 (r 2 ?? 0.9990) for tissue samples. Inter-day and intra-day accuracy (as relative error, RE) and precision (as relative standard deviation, RSD) were <5.94 and 6.05%, respectively. The limit of detection was 0.025 ??g mL?1 and extraction recovery for all samples was ??85.86%. The method was successfully applied to a tissue-distribution study after oral administration of 40 mg kg?1 paeonol to healthy Sprague?CDawley rats. The study showed that paeonol was quickly distributed and eliminated after oral administration; liver and kidney were the major distribution tissues of paeonol in rats, and paeonol quickly passed through the blood?Cbrain barrier. It was also found there was no long-term accumulation of paeonol in rat tissues.  相似文献   
5.
Li  Jie  Miao  Shan  Xie  Yanhua  Wang  Jianbo  Cao  Wei  Bi  Linlin  Wang  Siwang 《Chromatographia》2012,75(23):1415-1420

A simple RP-LC-UV method was established for the determination of tryptanthrin in plasma and different tissues of rats. The separation was achieved by HPLC on a C18 column with a mobile phases composed of acetonitrile–water (47:53, v/v), UV detection was used at 251 nm. Good linearity was found between 0.0183–1.1712 μg mL−1 (r 2 = 0.999) for plasma and 0.0937–1.7568 μg mL−1 for the tissue samples, respectively (r 2 ≥ 0.9932). The intra- and inter-day precisions expressed as the relative standard deviation for the method were 0.92–6.01 and 1.06–9.11 %, respectively. The relative recoveries of tryptanthrin ranged from 95.26 to 97.89 % for plasma and 82.55 to 114.99 % for tissue homogenates (except heart). The developed method was successfully applied to the pharmacokinetics and tissue distribution research after orally administration of a 56-mg kg−1 dose of tryptanthrin to healthy SD rats. The main pharmacokinetics distribution results showed that liver, lung, small intestine, and large intestine were the major distribution tissues of tryptanthrin in rats, and that tryptanthrin had difficulty in crossing the blood–brain barrier.

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6.
本文分析了薏苡的营养成分,它是一种营养的食品原料。  相似文献   
7.
Background: Microtubule-targeted drugs are the most effective drugs for adult patients with certain solid tumors. Taccalonolide AJ (AJ) can stabilize tubulin polymerization by covalently binding to β-tubulin, which enables it to play a role in the treatment of tumors. However, its clinical applications are largely limited by low water solubility, chemical instability in water, and a narrow therapeutic window. Clear-cell renal-cell carcinoma (cc RCC) accounts for approximately 70% of RCC cases and is prone to resistance to particularly targeted therapy drugs. Methods: we prepared a water-soluble cyclodextrin-based carrier to serve as an effective treatment for cc RCC. Results: Compared with AJ, taccalonolide AJ-hydroxypropyl-β-cyclodextrin (AJ-HP-β-CD) exhibited superior selectivity and activity toward the cc RCC cell line 786-O vs. normal kidney cells by inducing apoptosis and cell cycle arrest and inhibiting migration and invasion of tumor cells in vitro. According to acute toxicity testing, the maximum tolerated dose (MTD) of AJ-HP-β-CD was 10.71 mg/kg, which was 20 times greater than that of AJ. Assessment of weight changes showed that mouse body weight recovered over 7–8 days, and the toxicity could be greatly reduced by adjusting the injections from once every three days to once per week. In addition, we inoculated 786-O cells to generate xenografted mice to evaluate the anti-tumor activity of AJ-HP-β-CD in vivo and found that AJ-HP-β-CD had a better tumor inhibitory effect than that of docetaxel and sunitinib in terms of tumor growth and endpoint tumor weight. These results indicated that cyclodextrin inclusion greatly increased the anti-tumor therapeutic window of AJ. Conclusions: the AJ-HP-β-CD complex developed in this study may prove to be a novel tubulin stabilizer for the treatment of cc RCC. In addition, this drug delivery system may broaden the horizon in the translational study of other chemotherapeutic drugs.  相似文献   
8.
转化医学是进入21世纪以来国际生物医学及健康领域出现的新概念。它是基础研究到临床应用的双向过程,是临床实践与基础研究之间的循环式的研究体系,它不是一门新的学科,只是强调一种理念,是特定时代背景的产物。目前,转化医学研究主要涉及以下领域:肿瘤、心脑血管疾病、代谢疾病、精神疾病、运动系统疾病、遗传病、器官移植、组织工程、疾病诊断、药物研发、个体化治疗、干细胞研究、动物模型研究以及免疫学等。本文综述了在疾病诊断、组织工程领域、个体化治疗、新药研发以及发病机制中涉及到的生物无机化学问题。最后,展望了该新领域今后的发展方向和亟待研究的重要问题。  相似文献   
9.
A simple RP-LC-UV method was established for the determination of tryptanthrin in plasma and different tissues of rats. The separation was achieved by HPLC on a C18 column with a mobile phases composed of acetonitrile?Cwater (47:53, v/v), UV detection was used at 251?nm. Good linearity was found between 0.0183?C1.1712???g?mL?1 (r 2?=?0.999) for plasma and 0.0937?C1.7568???g?mL?1 for the tissue samples, respectively (r 2????0.9932). The intra- and inter-day precisions expressed as the relative standard deviation for the method were 0.92?C6.01 and 1.06?C9.11?%, respectively. The relative recoveries of tryptanthrin ranged from 95.26 to 97.89?% for plasma and 82.55 to 114.99?% for tissue homogenates (except heart). The developed method was successfully applied to the pharmacokinetics and tissue distribution research after orally administration of a 56-mg?kg?1 dose of tryptanthrin to healthy SD rats. The main pharmacokinetics distribution results showed that liver, lung, small intestine, and large intestine were the major distribution tissues of tryptanthrin in rats, and that tryptanthrin had difficulty in crossing the blood?Cbrain barrier.  相似文献   
10.
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