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1.
As a versatile therapeutic modality, peptides attract much attention because of their great binding affinity, low toxicity, and the capability of targeting traditionally “undruggable” protein surfaces. However, the deficiency of cell permeability and metabolic stability always limits the success of in vitro bioactive peptides as drug candidates. Peptide macrocyclization is one of the most established strategies to overcome these limitations. Over the past decades, more than 40 cyclic peptide drugs have been clinically approved, the vast majority of which are derived from natural products. The de novo discovered cyclic peptides on the basis of rational design and in vitro evolution, have also enabled the binding with targets for which nature provides no solutions. The current review summarizes different classes of cyclic peptides with diverse biological activities, and presents an overview of various approaches to develop cyclic peptide-based drug candidates, drawing upon series of examples to illustrate each strategy.  相似文献   
2.
目的 对采集自南海中部1781 m沉积环境的1株曲霉属真菌Aspergillus flavus SCSIO F025进行次生代谢产物及活性研究。方法 通过优化培养条件对菌株进行规模发酵,发酵产物采用硅胶柱层析、Sephadex LH-20、HPLC等色谱学方法进行化学分离,利用NMR、MS等波谱学技术并结合文献进行化合物的结构鉴定,应用纸片扩散法及DPPH自由基清除法对化合物进行初步抗氧化和抗菌活性测试。结果 从菌株SCSIO F025中分离鉴定5个单体化合物:penicillivinacine(1),arthrographol(2),dehydroxypaxilline(3),ditryptophenaline(4),kojic acid(5)。其中化合物1和2为首次从黄曲霉中分离得到。化合物1对溶藻弧菌和藤黄微球菌有弱的抑制活性,化合物2表现出显著抗氧化及溶藻弧菌和藤黄微球菌抑制活性,化合物3对溶藻弧菌和肺炎克雷伯杆菌有抑制活性。  相似文献   
3.
本文综述我国国内学者于2017年在天然产物化学领域所取得的主要原创性研究成果。文中所选取的天然化合物具有较新颖的结构和/或较显著的生物活性。据此,共选取本年度发表在国内外相关刊物共计122篇文献中的139个具有代表性的化合物,对它们的来源、结构特征和生物活性进行了介绍。  相似文献   
4.
系统综述了海绵Axinella属的生物碱、三萜、甾体等化学成分,及其抗肿瘤、抗菌、神经保护等生物活性的研究进展,为该属海绵的深入研究提供有用资料。  相似文献   
5.
In this study, a type 1 RIP, designated as Jc‐SCRIP, was first isolated from the seed coat of Jatropha curcas Linn. It was purified by ammonium sulfate precipitation and chromatography on DEAE‐Sephacel? and CM‐cellulose columns. Purification fold of Jc‐SCRIP increased 113.8 times, and the yield was 1.13% of the total protein in the final step. It was shown to be a monomeric glycoprotein with a molecular mass of 38 938 Da, as determined by MALDI‐TOF/MS. It exhibited hemagglutination activity and possessed strong N‐glycosidase activity. The antimicrobial activity of Jc‐SCRIP was tested against nine human pathogenic bacteria and one fungus; the most potent inhibitory activity was against Staphylococcus epidermidis ATCC 12228, with minimum inhibitory concentration value of 0.20 μm . Jc‐SCRIP demonstrated in vitro cytotoxicity against human breast adenocarcinoma cell line (MCF‐7), a colon adenocarcinoma (SW620), and a liver carcinoma cell line (HepG2), with IC50 values of 0.15, 0.25, and 0.40 mm , respectively. The results suggested that Jc‐SCRIP may be a potential natural antimicrobial and anticancer agent in medical applications.  相似文献   
6.
Urticaceae includes about 1300 species in 47 genera which largely spread in wet tropical regions, and 341 species in 25 genera are in China. Some species are used in Chinese folk medicine. So far, studies on chemistry and pharmacology of Urticaceous plants are mainly focused on nettle of Urtica L. In this review, the chemical researches on 35 new compounds and related pharmacological effects of the plants in Urticaceae reported during 2000-2010 are described. The 35 new compounds belong to the classes of lignan, secolignan, norlignan, flavonoid, alkaloid, sesquiterpenoid, triterpenoid, sterol, and sphingolipid. The main bioactivities include cytotoxic, antitumor, antimicrobial, antifungal, anti-BPH, anti-HIV, antidiabetic, hypolipidemic, 5α-reductase inhibitory, hair regrowth promotion, and anti-oxidative activities.  相似文献   
7.
The mulberry tree (Morus alba) plays a key role in agriculture, and its different parts have been used as popular Traditional Chinese Medicines for thousands of years. There are 16 species belonging to the Morus genus. Among them, 11 species distribute in China, most of which have been used as the substitutes of M. alba in local provinces. This review summarizes the structural characters of polyphenols, the main components in Morus, including Diels–Alder-type adducts, flavonoids, 2-arylbenzofurans, and stilbenes, and also their related bioactivities in the last 10 years.  相似文献   
8.
Urticaceae includes about 1300 species in 47 genera which largely spread in wet tropical regions,and 341 species in 25 genera are in China.Some species are used in Chinese folk medicine.So far,studies on chemistry and pharmacology of Urticaceous plants are mainly focused on nettle of Urtica L.In this review,the chemical researches on 35 new compounds and related pharmacological effects of the plants in Urticaceae reported during 2000-2010 are described.The 35 new compounds belong to the classes of lignan,secolignan,norlignan,flavonoid,alkaloid,sesquiterpenoid,triterpenoid,sterol,and sphingolipid.The main bioactivities include cytotoxic,antitumor,antimicrobial,antifungal,anti-BPH,anti-HIV,antidiabetic,hypolipidemic,5α-reductase inhibitory,hair regrowth promotion,and anti-oxidative activities.  相似文献   
9.
小花异裂菊中的芳香类化学成分及其活性   总被引:1,自引:1,他引:0  
目的:研究异裂菊属Heteroplexis植物小花异裂菊的化学成分.方法:采用乙醇提取、乙酸乙酯萃取、硅胶柱色谱、大孔树脂柱色谱、Pharmadex LH-20柱色谱、反相中压柱色谱、闪式柱色谱以及反相HPLC柱色谱分离;运用波谱数据测定和分析鉴定化合物的结构;采用人肿瘤细胞、HIV-1复制、MPP+诱导PC12细胞损伤和多形核白细胞β葡萄糖苷酸酶释放药理模型筛选其活性.结果:分离鉴定了31个化合物,包括12个苯丙素及其衍生物,(+)-(7S,8R)-3-甲氧基-4-羟基苯基丙三醇(1),阿魏酸(2),肉桂酸甲酯(3),1-二十醇-3,4-二羟基肉桂酸酯(4),morinin B(5),sinapyl diangelate(6),绿原酸(7),4-O-咖啡酰奎尼酸(8),5-O-咖啡酰奎尼酸(9),5-O-咖啡酰奎尼酸甲酯(10),1,5-O-二咖啡酰奎尼酸(11)和4,5-O-二咖啡酰奎尼酸甲酯(12);3个木脂素类,(+)-松脂素(13),青刺尖木脂醇(14)和(+)-松脂素-O-β-D-吡哺葡萄糖苷(15);4个苯乙酮类,2,4-二乙酰基茴香醚(16),espeleton(17),viscidone(18),12-羟基佩兰毒素-12-O-β-D-吡喃葡萄糖苷(19);9个黄酮类,异樱花素(20),橙皮素(21),3-甲氧基-5,7,3',4'-四羟基黄酮(22),金合欢素(23),5-羟基-7,4'-二甲氧基黄酮(24),7-甲氧基-4',5,6-三羟基黄酮(25),3,3'-二甲基槲皮素(26),山柰酚3-O-芦丁糖苷(27),芦丁(28);3个香豆素类,东莨菪内酯(29),7-羟基香豆素(30)和泽兰内酯(31).化合物6,22分别对人胃癌细胞(BGC-823)和人肺腺癌细胞(A549)具有一定的选择性生长抑制作用,IC50值分别为3.74×10-5,7.17×10-5mol·L-1;化合物6有抑制HIV-1病毒复制的活性,IC50值为4.04×10-6 mol·L-1;在1.0×10-5mol·L-1浓度下,化合物22对MPP+致PC12细胞损伤有保护作用,与模型组比较有显著性差异(P<0.01);化合物26和31能抑制PAF刺激的多形核白细胞β葡萄糖苷酸酶释放,抑制率分别为75.6%(P<0.001)和53.9%(P<0.01).结论:化合物1-31均为首次从异裂菊属植物中分离得到;化合物6和22分别对人胃癌细胞(BGC-823)和人肺腺癌细胞(A549)具有选择性生长抑制作用,化合物6有抑制HIV-1病毒复制的活性,化合物22具有神经细胞保护活性,化合物26和31有潜在抗炎活性,其他化合物在测试浓度下在以上筛选模型中未显示明显活性.  相似文献   
10.
火木层孔菌液体培养物的化学成分研究   总被引:2,自引:2,他引:0  
目的:研究针层孔属火木层孔菌Phellinus igniarius液体培养物的化学成分并对其在多种体外药理模型上进行随机活性筛选.方法:分别对发酵液及菌丝体的化学成分进行研究,采用硅胶柱色谱、Sephadex LH-20柱色谱以及反相HPLC柱色谱等分离方法进行分离纯化;运用光谱数据解析鉴定化合物结构;在细胞水平模型上,筛选化合物在肿瘤细胞毒、神经保护、肝保护、抗炎和抗HIV等方面的活性.结果:从发酵液和菌丝体2部分共分离鉴定了29个化合物,分别为3个倍半萜:3S,9R,10S-3-羟基-11,12-O-异丙基血苋烷烯(1),3S,9R,10S-3,11,12-三羟基血苋烷烯(2)和3S,4S,9R,10-11,12,14-三羟基血苋烷烯(3);3个甾体:24R-麦角甾-4,6,8(14),22-四烯-3-酮(4),豆甾-7,22-二烯-3β,5α,6α-三醇(5)和麦角甾5α,8α-过氧-6,22-二烯-3β-醇(6);14个环二肽:环(L-脯氨酸-L-缬氨酸)(7),环(L-亮氨酸-D-脯氨酸)(8),环(L-亮氨酸-L-脯氨酸)(9),环(异亮氨酸-脯氨酸)(10),环(甘氨酸-亮氨酸)(11),环(苯丙氨酸-丝氨酸)(12),环(丙氨酸-脯氨酸)(13),环(丙氨酸-苯丙氨酸)(14),环(4-羟基-脯氨酸-苯丙氨酸)(15),环(L-苯丙氨酸-D-脯氨酸)(16),环(D-苯丙氨酸-D-脯氨酸)(17),环(6-羟基-脯氨酸-苯丙氨酸)(18),环(谷氨酸氨-脯氨酸)(19)和环(天冬氨酸-亮氨酸)(20);9个其他类化合物:乙酰氨基苯丙氨酸(21)、腺苷(22)、苯乙二醇(23)、邻-羟基苯乙醇(24)、苯甲酸(25)、对-甲氧基苯甲酸(26)、间-甲氧基苯甲酸(27)、十六烷酸(28)和3-吡啶羧酸(29).化合物5和8在1×10-5mol·L-1时能够有效地抑制MPP+诱导的PC12-syn细胞损伤,相对保护率分别为90.3%和87.5%,与模型组比较有显著性差异(P<0.05).在1×10-5mol·L-1浓度下,化合物12和18可较好地保护DL-半乳糖胺诱导的WB-F344细胞损伤,细胞成活率分别为25%和24%(双环醇作为对照,细胞成活率为24%).结论:化合物1-29均为首次从针层孔属火木层孔菌液体培养物中分离鉴定;化合物5和S有神经细胞保护活性,化合物12和18具有肝细胞损伤保护活性,其他化合物在测试浓度下在以上筛选模型中未显示明确活性.  相似文献   
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