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排序方式: 共有507条查询结果,搜索用时 328 毫秒
21.
目的:建立指纹图谱、多指标定量相结合的头痛宁胶囊质量评价方法。方法:采用高效液相色谱法,选用Kromasil C18色谱柱(250 mm×4.6 mm,5 μm);以甲醇-0.1%磷酸水溶液为流动相,梯度洗脱;流速:1.0 mL·min-1;柱温:30℃;检测波长:220 nm(0~40 min)、290 nm(40~100 min);进样量:10 μL。运用"中药色谱指纹图谱相似度评价系统(2012版)"对15批样品色谱图进行分析,以落新妇苷为参照,确定22个共有峰为特征峰,相似度均>0.977;天麻素、阿魏酸、落新妇苷、5-O-甲基维斯阿米醇苷、二苯乙烯苷线性关系良好,r均>0.999 9,加样回收率在95.5%~98.9%,RSD<5%(n=6)。结论:该方法简便、准确及专属性强,可用于头痛宁胶囊质量控制和综合评价。 相似文献
22.
Jinfeng Li Bing Wang Guangjie Zhou Xiujuan Yan Yuan Zhang 《The American journal of the medical sciences》2018,355(6):588-596
Background
Tetrahydroxy stilbene glucoside (TSG) is an active ingredient of Heshouwu and is an antioxidant. The underlying mechanisms of the renoprotective effect of TSG in diabetic nephropathy have not been previously reported. In this study, we investigated the mechanisms of TSG in preventing podocytes injury in high glucose (HG) condition.Methods
Cultured mouse podocytes (MPC5) were incubated in HG (30 mmol/L) plus various concentration of TSG (0.1, 1 and 10 μM) for 48 hours. Reactive oxygen species (ROS) production, malondialdehyde (MDA) levels, terminal deoxynucleotidyl-transferase (TdT)-mediated dUTP-biotin nick end-labeling (TUNEL) fluorescence intensity, caspase-3 activity and the mRNA expression of nephrin in cultured podocytes were determined. The protein expression of Nod-like receptor protein 3 (NLRP3) inflammsome, interleukin-1β (IL-1β) and nephrin was detected by Western blot.Results
When the podocytes were incubated with various concentrations of TSG under HG conditions for 48 hours, TSG decreased ROS production, MDA levels, TUNEL fluorescence intensity and caspase-3 activity, but increased cell viability and the expression of nephrin in HG-induced podocytes in a dose-dependent manner. Subsequently, the podocytes treated with TSG at 10 μΜ decreased the expression of NLRP3 inflammasome and IL-1β compared with that of control. Furthermore, the podocytes transfected with NLRP3- small interfering RNA (siRNA) exhibited a significant decrease in the expression of caspase-1 and IL-1β, but exhibited a significant increase in the expression of nephrin. Eventually, TSG significantly increased the expression of nephrin in IL-1β-treated podocytes.Conclusions
TSG attenuates high glucose-induced cell apoptosis in vitro partly through the suppression of NLRP3 inflammasome signaling. 相似文献23.
An enzymatic approach to configurationally rare trans‐androsteronyl‐α‐glucoside and Its potential anticancer application
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Feng‐Pai Chou Chia‐Tse Tsai Ya‐Sheng Chiou Yi‐Ju Chen Meng‐Erh Li Ting‐Wei Guo Jason WenJay Lyu Sheng‐Hao Chou Tung‐Kung Wu 《Chemical biology & drug design》2017,89(1):61-66
Enzymatic glycosylation of sterols/steroids with glycosyltransferase HP0421 shows protein plasticity on generation of configurationally rare steryl‐α‐glucosides. Investigation of trans‐androsteronyl‐α‐glucoside on tamoxifen‐treated MCF‐7 breast cancer cells shows dose‐dependent depression of cell viability and enhanced drug effectiveness, illustrating a new avenue for the production of novel steryl‐α‐glucosides with useful biological activities. 相似文献
24.
Alkaloids occupy an important position in chemistry and pharmacology. Among the various alkaloids, berberine and coralyne of the protoberberine group, sanguinarine of the benzophenanthridine group, and aristololactam-beta-d-glucoside of the aristolochia group have potential to form molecular complexes with nucleic acid structures and have attracted recent attention for their prospective clinical and pharmacological utility. This review highlights (i) the physicochemical properties of these alkaloids under various environmental conditions, (ii) the structure and functional aspects of various forms of deoxyribonucleic acid (DNA) (B-form, Z-form, H(L)-form, protonated form, and triple helical form) and ribonucleic acid (RNA) (A-form, protonated form, and triple helical form), and (iii) the interaction of these alkaloids with various polymorphic DNA and RNA structures reported by several research groups employing various analytical techniques like absorbance, fluorescence, circular dichroism, and NMR spectroscopy; electrospray ionization mass spectrometry, thermal melting, viscosity, and DNase footprinting as well as molecular modeling and thermodynamic studies to provide detailed binding mechanism at the molecular level for structure-activity relationship. Nucleic acids binding properties of these alkaloids are interpreted in relation to their biological activity. 相似文献
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27.
Thi Quynh Do Bich Ngan Truong Thuy Linh Nguyen Van Hung Nguyen Hai Dang Nguyen 《Journal of Asian natural products research》2019,21(6):507-515
Four new compounds N-salicyl-3-hydroxyanthranilic acid methyl ester (1), N-(2′-dehydroxysalicyl)-3-hydroxyanthranilic acid methyl ester (2), methyl-4-β-D-allopyranosyl-ferulate (3), and methyl-4-β-D-gulopyranosyl-cinnamate (4), along with six known compounds (5–10), were isolated from the roots of Aconitum carmichelii Debx. Their structures were elucidated on the basis of spectral data analysis, including 1D, 2D-NMR, and HR-ESI-MS. Compounds 1 and 2 showed the inhibition of nitric oxide (NO) production with IC50 values of 9.13 and 19.94 μM, respectively. 相似文献
28.
目的 以大麻素2型受体(cannabinoid receptor type 2,CB2R)为靶点,从补肾中药覆盆子中分离、鉴定、筛选得到具有激动CB2R的激动剂,并探讨其抗骨质疏松作用的机制。方法 以激动CB2R活性为导向进行分离并筛选,采用正相硅胶柱色谱、凝胶柱色谱、大孔树脂、重结晶和半制备型高效液相色谱对二氯甲烷层和醋酸乙酯层浸膏进行分离,结合化合物理化性质和核磁共振波谱对分离得到的化合物进行结构鉴定。通过双荧光素酶方法筛选出具有可特异性激动CB2R的化合物,并通过测定转染CB2R的人胚胎肾细胞HEK293-CB2内环磷酸腺苷(cyclic adenosine monophosphate,c AMP)积聚水平和CB2R蛋白表达情况来验证筛选的化合物对CB2R的特异性激动活性,最后评价筛选得到的化合物对破骨细胞骨代谢方面的调节作用。结果 以激动CB2R为活性导向进行分离和筛选,共得到24个化合物,分别鉴定为山柰酚(1)、木犀草苷(2)、银椴苷(3)、金丝桃苷(4)、橙皮素(5)、刺芒柄花素(6)、槲皮素(7)、对羟基苯甲酸(8)、迷迭香酸(9)、对羟基苯甲酸乙酯(10)、水杨酸(11... 相似文献
29.
目的研究水溶性和尿素溶性粉尘螨糖蛋白的组分及结合糖链的构成. 方法用粉尘螨脱脂干粉提取水溶性抗原(Der fA)和尿素溶性抗原(Der fU),经SDS-PAGE,Western blot,免疫染色,胶体金染色和糖定性检测两种抗原糖蛋白的组分,并用9种HRP-植物血凝素进行结合糖链鉴定. 结果 Der fA显示4条蛋白带,分别为18 ku、30 ku、50 ku和58 ku,Der fU显示2条蛋白带(46 ku、58 ku),其中58 ku糖蛋白检测阳性.Der fA存在α-甘露糖(α-Man)、N-乙酰葡萄糖胺(GlcNAC)、α-葡萄糖(α-Glc),不存在寡糖(Oligosaccharide)、岩藻糖(α-Fuc)、β-半乳糖(β-Gal)、β-半乳糖-乙酰氨基半乳糖(β-Gal-GalNAC)及唾液酸(AS);Der fU只存在α-甘露糖,不存在其它7种糖链和唾液酸. 结论α-甘露糖是粉尘螨优势糖蛋白,其次是N-乙酰葡萄糖胺和α-葡萄糖. 相似文献
30.
目的:建立经典名方当归补血汤的质量标准。方法:应用薄层色谱鉴别方法,以对照药材、阿魏酸、藁本内酯以及黄芪甲苷为对照,建立当归补血汤物质基准的定性鉴别方法。采用高效液相色谱法测定当归补血汤中阿魏酸以及毛蕊异黄酮葡萄糖苷的含量,采用NewmateTM C18(250 mm×4.6 mm, 5μm)色谱柱,以乙腈-0.2%甲酸为流动相进行洗脱,流速0.5 mL/min,检测波长分别为316 nm和260 nm。结果:薄层色谱鉴别方法专属性良好,斑点清晰。阿魏酸、毛蕊异黄酮葡萄糖苷分别在进样量为10~200μg、5~50μg范围内线性关系良好,相关系数均>0.999;平均加样回收率分别为100.64%和92.62%,相对标准偏差(RSD)均<3%。15批样品中阿魏酸和毛蕊异黄酮葡萄糖苷含量分别在0.068%~0.109%和0.057%~0.092%范围内。结论:建立的方法准确可靠,可作为当归补血汤的质量控制标准。 相似文献