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11.
One new coumarin, 3,5-dihydroxy-7-O-α-L-rhamno pyranosyl-2H-chromen-2-one (1), was isolated from the whole plant of Sarcandra glabra. The structure was elucidated by spectroscopic methods. Our results indicated that 1 significantly inhibit nitric oxide (NO) production in LPS-induced RAW264.7 macrophages. RT-PCR analysis indicated it inhibited iNOS mRNA expression. In addition, Western blot analysis showed that 1 attenuated LPS-induced synthesis of iNOS protein in the macrophages. These results suggest that 1 could be potential anti-inflammatory agent by down-regulating iNOS expression.  相似文献   
12.
Fourteen new norditerpenoids (abiesanordines A-N, 1-14), including a novel podocarpene bearing a rare enolic structure (abiesanordine A, 1), were isolated from Abies georgei together with eight known ones. Their structures were determined mainly by detailed analysis of 1D and 2D NMR spectroscopic data including HSQC, DQF COSY, HMBC, and NOESY. All the isolates were tested for inhibitory activities against LPS-induced NO production in RAW264.7 macrophages, abiesanordine I (9) showed the strongest activity with the IC50 value of 17.0 μg/mL. Furthermore, it exhibited no cytotoxicity against RAW264.7 macrophages under the concentration of 50 μg/mL.  相似文献   
13.
Species of Podocarpus are used traditionally in their native areas for the treatment of fevers, asthma, coughs, cholera, chest pain, arthritis, rheumatism, and sexually transmitted diseases. To identify natural products having efficacy against inflammatory bowel disease (IBD), we identified a new, 16-hydroxy-4β-carboxy-O-β-D-glucopyranosyl-19-nor-totarol (4) together with three known diterpenoids from P. macrophyllus. Furthermore, all the extracts, fractions, and isolates 1–4 were investigated for their anti-inflammatory effects by assessing the expression on nitric oxide (NO) production and proinflammatory cytokines in lipopolysaccharide (LPS)-stimulated RAW 264.7 and HT-29 cells. Among them, nagilactone B (2) exhibited a potent anti-inflammatory effect against NO production on RAW 264.7 cells; therefore, nagilactone B was further assessed for anti-inflammatory activity. Western blot analysis revealed that nagilactone B significantly decreased the expression of LPS-stimulated protein, inducible nitric oxide synthase (iNOS), cyclooxygenase (COX)-2, and phosphorylated extracellular regulated kinase (pERK)1/2. In addition, nagilactone B downregulated tumor necrosis factor (TNF)-α, interleukin (IL)-6, and IL-8 levels in LPS-induced macrophages and colonic epithelial cells. To our best knowledge, this is the first report on the inhibitory effect of nagilactone B (pure state) and rakanmakilactone G against NO production in LPS-stimulated RAW 264.7 cells. Thus, diterpenoids isolated from P. macrophyllus could be employed as potential therapeutic phytochemicals for IBD.  相似文献   
14.
The anti-inflammatory activity of tea polyphenols(TPs) in RAW264.7 macrophages stimulated by lipopolysaccharide(LPS) was investigated in this paper. RAW264.7 macrophages were treated with different concentrations of TP(0, 12.5, 25, 50, 100, and 200 μg/mL) and then stimulated by LPS. Another blank control group was set up. The expression of pro-inflammatory cytokines associated with the nuclear factor-kappa B(NF-κB) signaling pathway was investigated before and after TP treatment. Pretreatment of RAW264.7 cells with TP decreased the expression of tumor necrosis factor-α(TNF-α), interleukin-6(IL-6) and interleukin 1 beta(IL-1β) pro-inflammatory cytokines. In addition, TP inhibited the phosphorylation of p65 and IκB by blocking the phosphorylation and the degradation of NF-κB inhibitor protein. In conclusion, TP exerts anti-inflammatory effects by regulating the release of inflammatory mediators via the NF-κB signaling pathway.  相似文献   
15.
The study aims to develop a rapid, sensitive ultra‐performance liquid chromatography coupled with an electrospray ionization quadruple time‐of‐flight tandem mass spectrometry (UPLC/Q‐TOF‐MS) analytical method for identifying glycerophospholipids (GPLs) from RAW264.7 cells. A total of 78 GPLs including 22 phosphatidylethanolamines (PEs), 49 phosphatidylcholines (PCs), four phosphatidylglycerols, one phosphatidylinositol and two unknown GPLs were identified. PC (14:0/16:1), PC (14:0/16:0), PE (0:0/20:3), PE (22:5/0:0) and PE (22:3/0:0) were identified for the first time. The UPLC/Q‐TOF‐MS method is suitable for targeting analysis of GPLs from RAW264.7 cells, which allows us to find out new GPLs compositions related to inflammatory diseases and to explain their pharmacological roles in inflammatory process. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
16.
In this study, we realized the continual and long-term electrochemical detection of NO production by stimulated macrophages using modified porphyrinic microsensor. The NO release from RAW 264.7 cells stimulated by lipopolysaccharide started 5 h after the lipopolysaccharide administration. After reaching its maximum at the sixth hour, the stable level of NO production was observed between the seventh and 12th hour of the experiment. This phase was followed by a gradual decline in NO production. A close correlation between the NO signal detected with microelectrode and nitrite accumulation, which had been determined in supernatants removed from stimulated cells, was observed. This finding was utilized for the calibration of the electrochemical experiment. The presence of iNOS enzyme, which constitutes a main requirement for NO production by stimulated macrophages, was confirmed by Western blot analysis of iNOS protein expression at key time points of the corresponding electrochemical experiment. The capability of our microsensor to instantaneously monitor the changes in the NO production by stimulated RAW 264.7 cells was demonstrated by the immediate decrease in the signal due to NO as a response to the addition of iNOS inhibitor into the cell culture medium. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   
17.
Twenty-two new sesquiterpenes were isolated from the aerial parts of Inula japonica Thunb., together with fifteen known ones. Their structures were determined by detailed spectroscopic analysis, X-ray diffraction studies, and modified Mosher method. All 37 compounds were evaluated for the inhibition of LPS-induced nitric oxide (NO) production in RAW264.7 macrophages, and most of isolates significantly inhibited the NO production with IC50 values in the range of 3.5-20 μM. Besides, results obtained in our studies provided a structure-activity relationship that would be used to design anti-inflammatory agents in the future.  相似文献   
18.
目的观察原花青素及其与抗炎活性成分(积雪草苷、姜黄素、茶多酚)的组合物对氧化低密度脂蛋白(ox- LDL)刺激巨噬细胞形成泡沫细胞过程中炎症细胞因子和细胞内胆固醇含量的变化。方法以体外培养的小鼠单核巨噬细胞系RAW264.7细胞为材料和ox- LDL刺激RAW264.7细胞24h形成泡沫细胞为模型,RT- PCR方法检测细胞因子IL-1β和TNF-αmRNA水平,试剂盒测定细胞内游离胆固醇和总胆固醇的含量。结果原花青素及其与积雪草苷、姜黄素、茶多酚组合物可明显降低泡沫细胞内的胆固醇酯与总胆固醇的比值,抑制泡沫细胞的形成,显著抑制泡沫细胞的IL-1β和TNF-αmRNA表达,其中原花青素与姜黄素的组合物作用最强。结论原花青素组合物通过降低细胞内胆固醇酯的含量,减轻细胞泡沫化程度和减轻细胞的炎症反应起到抗动脉粥样硬化的作用。  相似文献   
19.
Two unusual cembranoids, sarcofuranocembrenolides A (1) and B (2), were isolated from a soft coral Sarcophyton sp. together with five known cembranoids (3-7). Compound 1 had a unique carbon skeleton of 8,19-bisnorfuranocembrenolide. Compound 2 was a furanocembrenolide, but a C1 unit (C-20) was attached to C-10 instead of C-12 of the ordinary cembrenolides. These rearrangements are unique in the biosynthesis of cembranoid diterpenes. Lobohedleolide (5), (7Z)-lobohedleolide (6), and denticulatolide (7) inhibited the colony formation of V79 cells at ED50 values of 4.6 (abt. 1.52), 3.7 (1.22), and 3.6 (1.40) μM (μg/mL), respectively, and reduced TNF-α production from LPS-stimulated RAW264.7 cells at 3.0-10.0 μM.  相似文献   
20.
This study aims at investigating physical–chemical properties of a water-soluble heteropolysaccharide from Plnatago asiatica L. leaves, and its immunomodulatory effects on macrophages RAW264.7 cells. Hot water-extracted crude polysaccharide from the plant leaves (PLLCP) was fractionated into four fractions by DEAE Sepharose Fast Flow eluted with 0.1–0.5 M NaCl solutions. The most abundant fraction (0.3 M NaCl elution), designated PLLP-2, was identified as a heteropolysaccharide with an average molecular weight (Mw) of 3.54 × 104 and composed mainly of Gal (34.4%), GalA (36.5%), Ara (10.1%) and Rha (8.4%). PLLP-2 was an acidic polysaccharide exhibiting inflaky curly aggregation with smooth surface. PLLCP and its main subfraction PLLP-2 displayed immunomodulatory activities by stimulating the production of pro-inflammatory cytokines, including TNF-α and IL-1β in macrophage RAW264.7 cells. These results indicate that the main polysaccharide fraction purified from P. asiatica L. leaves is probably pectin, and have potential immunomodulatory function.  相似文献   
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