全文获取类型
收费全文 | 128篇 |
免费 | 5篇 |
国内免费 | 19篇 |
专业分类
化学 | 109篇 |
晶体学 | 1篇 |
力学 | 12篇 |
综合类 | 1篇 |
数学 | 5篇 |
物理学 | 24篇 |
出版年
2024年 | 3篇 |
2023年 | 9篇 |
2022年 | 11篇 |
2021年 | 13篇 |
2020年 | 9篇 |
2019年 | 6篇 |
2018年 | 8篇 |
2017年 | 3篇 |
2016年 | 9篇 |
2015年 | 13篇 |
2014年 | 8篇 |
2013年 | 7篇 |
2012年 | 9篇 |
2011年 | 14篇 |
2010年 | 3篇 |
2009年 | 5篇 |
2008年 | 3篇 |
2007年 | 6篇 |
2006年 | 5篇 |
2005年 | 1篇 |
2004年 | 3篇 |
2002年 | 1篇 |
1996年 | 1篇 |
1993年 | 1篇 |
1957年 | 1篇 |
排序方式: 共有152条查询结果,搜索用时 15 毫秒
61.
Xuan Wang Jiaxiang Liu Ziqin Yan Xiaohong Liu Sixiu Liu Yanrui Suo Weiwei Lu Jinfeng Yue Kaixian Chen Hualiang Jiang Yujun Zhao Mingyue Zheng Dongcheng Dai Xiaojie Lu 《Chemical science》2021,12(8):2841
DNA-encoded library technology (DELT) employs DNA as a barcode to track the sequence of chemical reactions and enables the design and synthesis of libraries with billions of small molecules through combinatorial expansion. This powerful technology platform has been successfully demonstrated for hit identification and target validation for many types of diseases. As a highly integrated technology platform, DEL is capable of accelerating the translation of synthetic chemistry by using on-DNA compatible reactions or off-DNA scaffold synthesis. Herein, we report the development of a series of novel on-DNA transformations based on oxindole scaffolds for the design and synthesis of diversity-oriented DNA-encoded libraries for screening. Specifically, we have developed 1,3-dipolar cyclizations, cyclopropanations, ring-opening of reactions of aziridines and Claisen–Schmidt condensations to construct diverse oxindole derivatives. The majority of these transformations enable a diversity-oriented synthesis of DNA-encoded oxindole libraries which have been used in the successful hit identification for three protein targets. We have demonstrated that a diversified strategy for DEL synthesis could accelerate the application of synthetic chemistry for drug discovery.Constructing DNA-encoded oxindole libraries by a diversified strategy. 相似文献
62.
X. F. Liu R. F. Li Xiaoyi Fu Hui Shen Mingyue wen X. Feng 《Russian Journal of Coordination Chemistry》2018,44(5):353-358
Reactions between dichloro-bridged copper(I) complexes and amides with different carbonyl substituents (CF3, CH3, and Ph) were reported. Two neutral Cu(I)-amido complexes, [Cu(Dppf)(MOAA)] (I) and [Cu(Dppf)(MOTFAA)] (II) (Dppf = 1,1'-bis(diphenylphosphino)ferrocene, MOAA and MOTFAA = deprotonated N-(4-methoxyphenyl) acetamide and N-(4-methoxyphenyl) trifluoroacetamide, respectively), were synthesized in moderate to good yield and characterized by element analysis, 1H NMR and X-ray crystallography method (СIF file CCDC no. 1015222 (I)). The results showed that the production of Cu(I)- amido complxes were influenced by carbonyl substituent in the order of Ph > CF3 > CH3. The substituent effect also appeared in the N-arylation reactions of I and II with iodobenzene, which generated another copper(I) complex Cu(Dppf)I (III) and two amides products [N-methyl-N-(4-methoxyphenyl) acetamide] (А) and [N-methyl-N-(4-methoxyphenyl) trifluoroacetamide] (B) in different yield. The formation and transformation of the Cu(I)-amido complexes could indicate their dynamiccompetency as the intermediates of Goldberg reaction. 相似文献
63.
Mingyue Jiang Wenjie Zhang Xu Yang Fen Xiu Haoran Xu 《Natural product research》2018,32(20):2431-2436
A novel isoindole alkaloid named oleraisoindole (1), together with six known compounds, 7′-ethoxy-trans-feruloyltyramine (2), N-trans-feruloyltyramine (3), N-trans-feruloyl-3-methoxytyramine (4), N-trans-p-coumaroyltyramine (5) aurantiamide (6) and ferulic acid methyl ester (7) were isolated from Portulaca oleracea L. Compounds 2 and 7 were isolated for the first time from this plant. Compound 1 was identified using spectroscopic methods including HR-ESI-TOF-MS, 1D-NMR, 2D-NMR. It was tested in a nitric oxide (NO) inhibition assay and was shown to inhibit NO production in RAW 264.7 cells induced by LPS. 相似文献
64.
研究了一种新的恶唑酮类衍生物GANRA-5对于人胚肺细胞MRC-5的辐射防护作用。以MTT评价其对于细胞的毒性,以γH2AX foci形成法检测其对于辐照后细胞中双链断裂的影响,发现其对于受到X射线和12C6+离子照射的细胞具有较强的辐射防护作用,并进一步发现其能够显著清除辐照后细胞内的自由基。这些结果表明,GANRA-5具有较低的细胞毒性,并能够通过清除自由基发挥较强的针对X射线和12C6+离子的辐射防护作用,有望开发为高效的辐射防护药物。 相似文献
65.
Zhenmin Yang Yongtao Yi Chuanchuan Gao Dengke Hou Jun Hu Mingyue Zhao 《Journal of separation science》2010,33(1):120-125
Inulin‐type oligosaccharides with different DP were prepared by size‐exclusion chromatography and purity of each oligosaccharide was determined by HPLC equipped with cyclodextrin‐bond column. The purities of obtained inulin‐type oligosaccharides with different DP were more than 98% by one‐step process. The DP and molecular weight were obtained through ESI‐MS in negative mode. The characterization of the inulin‐type oligosaccharides with different DP was studied by MS/MS spectra obtained by collision‐induced dissociation of molecular ions ([M?H]?). When the DP was lower, the fragment ions were formed through cross‐ring cleavages of two bonds within the sugar ring and glycosidic cleavages. However, with the increase of DP, the ions resulting from glycosidic cleavages between two sugar residues were predominant. 相似文献
66.
Dentinogenesis is a necessary prerequisite for dental tissue engineering. One of the steps for dentinogenesis is to obtain large quantities of highly purified odontoblasts. Therefore, we have undertaken an experiment applying different concentrations of β-glycerophosphate (β-GP) to induce the differentiation of dental pulp stem cells (DPSCs) in a long-term 28-day culture. In the meanwhile, we have studied the time- and maturation-dependent expression of matrix extracellular phosphoglycoprotein (MEPE) and that of the odontoblast-like marker-dentin sialoprotein (DSP), in order to investigate an optimized mineralized condition. Western blot results revealed that the expression of DSP became lower when accompanied by the increase of the β-GP concentration, and there was also an influence on MEPE expression when different concentrations of β-GP were applied. Meanwhile, the mineralized groups had an inhibitory function on the expression of MEPE as compared with the control group. Above all, all experimental groups successfully generated mineralized nodules by Alizarin Red S and the 5 mM β-GP group formed more mineralized nodules quantitated using the CPC extraction method. In conclusion, there is a significant modulation of the β-GP during the differentiation of the DPSCs. The degree of odontoblast differentiation is β-glycerophosphate concentration dependent. A low concentration of β-GP (5 mM) has been shown to be the optimal concentration for stimulating the maturation of the DPSCs. Moreover, MEPE accompanied with DSP clearly demonstrates the degree of the differentiation. 相似文献
67.
The O3-initiated oxidation of vinyl propionate is studied using quantum chemistry calculations. Detailed and complete reaction mechanisms are presented which involve the formation of the primary ozonide (POZ), the subsequent decomposition of POZ, the secondary reactions of CH3CH2C(O)OCHO2 (IM4) in the presence of H2O or NO as well as the generation of the secondary ozonide (IM6). Based on the above PESs calculations, the Multichannel Rice–Ramsperger–Kassel–Marcus theory is employed to calculate the total and individual rate constants for major product channels. The rate constants and branching ratios of main products are obtained. The total rate constants are temperature dependent over the whole study temperature range (200–2,000 K), but pressure independent over the range of 0.01–10,000 Torr. In addition, the atmospheric lifetime is estimated in accordance with rate constants. 相似文献
68.
Set-valvedMarkovProcessesandTheirRepresentationTheoremsXuMingyue(徐明跃)(DepartmentofMathematics,HavenNormalUniversity,Harbin,15... 相似文献
69.
Li L Li M Sun Y Li J Sun L Zou G Zhang X Jin W 《Chemical communications (Cambridge, England)》2011,47(29):8292-8294
Novel electrochemiluminescence resonance energy transfer (ECRET) between an emitter electrochemically generated by luminol as the donor and luminescent quantum dots as the acceptor is investigated. The ECRET technique can be used to study the interactions and conformational changes of proteins. 相似文献
70.
Wang F Liu D Wang H Luo C Zheng M Liu H Zhu W Luo X Zhang J Jiang H 《Journal of chemical information and modeling》2011,51(11):2821-2828
The three-dimensional (3D) structures of most protein targets have not been determined so far, with many of them not even having a known ligand, a truly general method to predict ligand-protein interactions in the absence of three-dimensional information would be of great potential value in drug discovery. Using the support vector machine (SVM) approach, we constructed a model for predicting ligand-protein interaction based only on the primary sequence of proteins and the structural features of small molecules. The model, trained by using 15,000 ligand-protein interactions between 626 proteins and over 10,000 active compounds, was successfully used in discovering nine novel active compounds for four pharmacologically important targets (i.e., GPR40, SIRT1, p38, and GSK-3β). To our knowledge, this is the first example of a successful sequence-based virtual screening campaign, demonstrating that our approach has the potential to discover, with a single model, active ligands for any protein. 相似文献