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31.
槲皮素与3d-过渡金属二价离子的配位反应研究 总被引:4,自引:0,他引:4
利用配体在配位反应前后的UV吸收变化与反应转化的关系,对槲皮素与3d-过渡金属二价离子在非水体系下的配位反应进行了探讨.实验表明,槲皮素金属配位反应活性受其羟氧自由离子的影响.同时,不同阴离子的同金属盐参与的配位反应会得到不同结构和性质的配位产物,也影响槲皮素的金属配位活性;槲皮素-金属配位反应对不同金属离子的反应配比不同.水和温度对配位反应的转化率会产生影响. 相似文献
32.
采用八通道微量热法探讨槲皮素镧配合物对粟酒裂殖酵母细胞生长代谢热动力学的影响。测定在槲皮素镧配合物作用下S.Pombe细胞的生长代谢产热曲线,并研究其生长速率常数(k)、最大发热功率(pmax)、达最大发热功率时间(tmax)和抑制率(I)等热动力学参数。微量热结果表明:随着槲皮素镧配合物浓度c的增大,最大发热功率pmax和速率常数k减小;达最大发热功率时间tmax和抑制率I增大。研究表明槲皮素镧配合物对粟酒裂殖酵母细胞生长代谢产生了抑制作用。 相似文献
33.
34.
铋(Ⅲ)-槲皮素极谱络合吸附波及微量铋的测定 总被引:1,自引:0,他引:1
在pH=3.8,0.4 mol/L的HCOOHHCOONa缓冲溶液中,铋与槲皮素的络合物在单扫极谱仪上能形成灵敏的络合物吸附波。该波在Bi3+离子浓度为4 × 10-8~6×10-6mol/L范围内与波高 hp成正比关系,检出限达到1×10-8mol/L。对电极反应的机理进行了研究。利用该极谱波测定了铅基轴承合金中的铋含量。 相似文献
35.
36.
为完善安神宝颗粒的质量控制标准,采用高效液相色谱法同时测定安神宝颗粒中酸枣仁皂A、东莨菪内酯、槲皮素3种有效成分,采用Agilent Zorbox SB C18色谱柱(4.6mm×150mm,5μm)及蒸发光散射检测器,柱温35℃,流动相为甲醇-0.5%的冰醋酸水溶液,梯度洗脱,流速为1.0mL/min,进样量10μL。结果表明,在该色谱条件下,3种有效成分均完全分离,峰面积对数与进样量对数呈良好的线性关系(r=0.995 6~0.998 0);精密度、重复性、稳定性试验结果符合要求,各被测组分的平均回收率在94.74%~96.08%之间。液相色谱法操作简单,准确度、灵敏度高,可用于检测安神宝颗粒中的有效成分,对完善安神宝颗粒质量标准,提升药品的质量控制水平具有实际意义。 相似文献
37.
根据配位化学及中药学的研究理论,结合槲皮素稀土配合物的结构特点,将槲皮素与稀土Dy3+离子按1:1比例配合形成稳定二元体系配合物,其分子式为DyC15H8O7Cl2·6H2O。研究表明,在紫外光谱中,配合物的吸收波长分别红移了11nm和38nm;红外光谱显示槲皮素分子中1656.42 cm-1上的苯环骨架在槲皮素-Dy3+配合物中消失,表明槲皮素羰基中的氧与Dy3+发生了反应;在荧光光谱中,配合物在最大激发波长为253 nm及最大发射波长为582 nm时表现出强的荧光效应;在二元体系中加入表面活性剂(曲拉通X-100和Tween 20)形成三元配合物,当加入量为2.0 mL时,三元配合物的荧光强度分别是二元体系的荧光强度的1.5倍和2倍。 相似文献
38.
In the course of phytochemical investigations of Melia azedarach leaves, a novel cinnamoyl glycoside, cinnamoyl-1-α-L-rhamnoside (1), and a novel acylated quercetin triglycoside, quercetin-3-O-[rhamnosyl 1→6(4″-lactoyl glucoside)]-4′-O-glucoside (2), have been isolated and characterized on the basis of spectroscopic methods, together with the six known flavonoid compounds
kaempferol-3-O-rutinoside, 3-O-rhamnoside, quercetin-3-O-rutinoside, 3-O-rhamnoside, and the aglycones quercetin and kaempferol. All isolated compounds have been evaluated for their structures by
chromatographic methods, chemical degradation, and UV and NMR spectroscopy. The antioxidant activity of the extract was studied
as well.
Published in Khimiya Prirodnykh Soedinenii, No. 1, pp. 12–14, January–February, 2008. 相似文献
39.
Luca Sancineto Carmine Ostacolo David Ortega-Alarcon Ana Jimenez-Alesanco Laura Ceballos-Laita Sonia Vega Olga Abian Adrian Velazquez-Campoy Silvia Moretti Agnieszka Dabrowska Pawel Botwina Aleksandra Synowiec Anna Kula-Pacurar Krzysztof Pyrc Nunzio Iraci Claudio Santi 《Molecules (Basel, Switzerland)》2021,26(19)
The COVID-19 pandemic outbreak prompts an urgent need for efficient therapeutics, and repurposing of known drugs has been extensively used in an attempt to get to anti-SARS-CoV-2 agents in the shortest possible time. The glycoside rutin shows manifold pharmacological activities and, despite its use being limited by its poor solubility in water, it is the active principle of many pharmaceutical preparations. We herein report our in silico and experimental investigations of rutin as a SARS-CoV-2 Mpro inhibitor and of its water solubility improvement obtained by mixing it with l-arginine. Tests of the rutin/l-arginine mixture in a cellular model of SARS-CoV-2 infection highlighted that the mixture still suffers from unfavorable pharmacokinetic properties, but nonetheless, the results of this study suggest that rutin might be a good starting point for hit optimization. 相似文献
40.
The COVID-19 pandemic is caused by SARS-CoV-2 and is leading to the worst health crisis of this century. It emerged in China during late 2019 and rapidly spread all over the world, producing a broad spectrum of clinical disease severity, ranging from asymptomatic infection to death (4.3 million victims so far). Consequently, the scientific research is devoted to investigating the mechanisms of COVID-19 pathogenesis to both identify specific therapeutic drugs and develop vaccines. Although immunological mechanisms driving COVID-19 pathogenesis are still largely unknown, new understanding has emerged about the innate and adaptive immune responses elicited in SARS-CoV-2 infection, which are mainly focused on the dysregulated inflammatory response in severe COVID-19. Polyphenols are naturally occurring products with immunomodulatory activity, playing a relevant role in reducing inflammation and preventing the onset of serious chronic diseases. Mainly based on data collected before the appearance of SARS-CoV-2, polyphenols have been recently suggested as promising agents to fight COVID-19, and some clinical trials have already been approved with polyphenols to treat COVID-19. The aim of this review is to analyze and discuss the in vitro and in vivo research on the immunomodulatory activity of quercetin as a research model of polyphenols, focusing on research that addresses issues related to the dysregulated immune response in severe COVID-19. From this analysis, it emerges that although encouraging data are present, they are still insufficient to recommend polyphenols as potential immunomodulatory agents against COVID-19. 相似文献