全文获取类型
收费全文 | 166篇 |
免费 | 4篇 |
专业分类
化学 | 140篇 |
数学 | 15篇 |
物理学 | 15篇 |
出版年
2023年 | 1篇 |
2021年 | 3篇 |
2020年 | 4篇 |
2019年 | 2篇 |
2018年 | 2篇 |
2017年 | 2篇 |
2016年 | 3篇 |
2015年 | 4篇 |
2014年 | 4篇 |
2013年 | 4篇 |
2012年 | 8篇 |
2011年 | 11篇 |
2010年 | 9篇 |
2009年 | 8篇 |
2008年 | 12篇 |
2007年 | 11篇 |
2006年 | 7篇 |
2005年 | 7篇 |
2004年 | 3篇 |
2003年 | 9篇 |
2002年 | 7篇 |
2001年 | 2篇 |
1998年 | 1篇 |
1997年 | 2篇 |
1996年 | 4篇 |
1994年 | 6篇 |
1993年 | 9篇 |
1992年 | 1篇 |
1991年 | 5篇 |
1990年 | 1篇 |
1988年 | 1篇 |
1987年 | 1篇 |
1985年 | 1篇 |
1983年 | 5篇 |
1981年 | 1篇 |
1979年 | 2篇 |
1973年 | 2篇 |
1941年 | 1篇 |
1938年 | 1篇 |
1935年 | 1篇 |
1933年 | 2篇 |
排序方式: 共有170条查询结果,搜索用时 15 毫秒
1.
Ariadna Lázaro Cristina Balcells Dr. Josefina Quirante Prof. Josefa Badia Prof. Laura Baldomà Dr. Jas S. Ward Prof. Kari Rissanen Dr. Mercè Font-Bardia Prof. Laura Rodríguez Dr. Margarita Crespo Prof. Marta Cascante 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(9):1947-1952
Platinum-based chemotherapy persists to be the only effective therapeutic option against a wide variety of tumours. Nevertheless, the acquisition of platinum resistance is utterly common, ultimately cornering conventional platinum drugs to only palliative in many patients. Thus, encountering alternatives that are both effective and non-cross-resistant is urgent. In this work, we report the synthesis, reduction studies, and luminescent properties of a series of cyclometallated (C,N,N′)PtIV compounds derived from amine–imine ligands, and their remarkable efficacy at the high nanomolar range and complete lack of cross-resistance, as an intrinsic property of the platinacycle, against multiplatinum-resistant colorectal cancer (CRC) and castration-resistant prostate cancer (CRPC) metastatic cell lines generated for this work. We have also determined that the compounds are effective and selective for a broader cancer panel, including breast and lung cancer. Additionally, selected compounds have been further evaluated, finding a shift in their antiproliferative mechanism towards more cytotoxic and less cytostatic than cisplatin against cancer cells, being also able to oxidize cysteine residues and inhibit topoisomerase II, thereby holding great promise as future improved alternatives to conventional platinum drugs. 相似文献
2.
Antonio Prez-Glvez María Visitacin Calvo Josefa Aguayo-Maldonado Javier Fontecha 《Molecules (Basel, Switzerland)》2021,26(7)
Several studies have been published regarding the effect of different factors on the digestion of milk lipids, considering their natural structural arrangement as milk fat globules and the efficiency of the digestive enzymes in the lipolysis of such complex structures. During digestion, the lipolytic products are dispersed in vesicles and micelles, which are the source for absorption of digested lipids. Therefore, it is necessary to consider the isolation of the micellar phase from the digesta to appropriately determine the amounts and classes of lipids which are bioaccessible. This study presents an integrative approach that included an isolation procedure to separate the micellar fraction from undigested and non-micellar parts, and the distribution of digested milk lipids in micelles determined directly through chromatographic techniques. Four groups of five full term mothers donated colostrum or mature milk. Two sets of samples were analyzed directly (raw), and two sets were pasteurized and then analyzed. Our data revealed that the profile of digested milk lipids is different depending on the lactation period and processing stage, while the carbon atom number distribution of the digested triacylglycerols in the micellar fraction provides a substantial information regarding the acylglycerols species that are less available for absorption. 相似文献
3.
4.
5.
Rodrigo Casasnovas David Fernández Joaquín Ortega-Castro Juan Frau Josefa Donoso Francisco Muñoz 《Theoretical chemistry accounts》2011,130(1):1-13
CBS-QB3, two simplified and less computationally demanding versions of CBS-QB3, DFT-B3LYP, and HF quantum chemistry methods
have been used in conjunction with the CPCM continuum solvent model to calculate the free energies of proton exchange reactions
in water solution following an isodesmic reaction approach. According to our results, the precision of the predicted pK
a values when compared to experiment is equivalent to that of the thermodynamic cycles that combine gas-phase and solution-phase
calculations. However, in the aqueous isodesmic reaction schema, the accuracy of the results is less sensitive to the presence
of explicit water molecules and to the global charges of the involved species since the free energies of solvation are not
required. In addition, this procedure makes easier the prediction of pK
a values for molecules that undergo large conformational changes in solvation process and makes possible the pK
a prediction of unstable species in gas-phase such as some zwitterionic tautomers. The successive pK
a values of few amino acids corresponding to the ionization of the α-carboxylic acid and α-amine groups, which is one of the
problematic cases for thermodynamic cycles, were successfully calculated by employing the aqueous isodesmic reaction yielding
mean absolute deviations of 0.22 and 0.19 pK
a units for the first and second ionization processes, respectively. 相似文献
6.
Nisha Kushwah Soumyaditya Mula Amey P. Wadawale Meenakshi Joshi Kedarnath Gotluru Mukesh Kumar Tapan K. Ghanty Sandip K. Nayak Vimal K. Jain 《Journal of heterocyclic chemistry》2019,56(9):2499-2507
Salicylaldimine Schiff bases represent an important class of hetero‐polydentate ligands capable of forming mononuclear, binuclear, and polynuclear complexes with transition and non‐transition metals. In this report, we developed an easy synthesis of BODIPY‐based salicylaldimine Schiff bases and synthesized five new derivatives. These were characterized by elemental analysis, infrared, UV‐Vis, nuclear magnetic resonance spectroscopy, and X‐ray crystallography. Finally, one of the Schiff bases was reacted with BF3·OEt2 to synthesize corresponding bis‐BF2 boron complex. The photophysical and electrochemical properties of the Schiff bases and the boron complex were evaluated and rationalized by theoretical calculations. The bis‐BF2 boron complex showed excited state charge redistribution, thus could be useful as sensitizers for designing new dye‐sensitized solar cells. 相似文献
7.
H. Ilzhöfer P. A. Kometiani Josefa Cvitl G. Roeder K. Jeschki W. Mohr M. E. Schulz B. van der Burg A. Peña und R. Martin 《Fresenius' Journal of Analytical Chemistry》1933,91(5-6):235-238
Ohne Zusammenfassung 相似文献
8.
9.
10.
In this paper, we propose a new design for the recursive least-squares (RLS) Wiener fixed-lag smoother and filter in linear discrete-time wide-sense stationary stochastic systems. It is assumed that the signal is observed with additive white observation noise. The signal is uncorrelated with the observation noise. The estimators require knowledge of the system matrix, the observation matrix and the variance of the state vector. These quantities can be obtained from the auto-covariance function of the signal. In the estimation algorithms, moreover, the variance of the observation noise is assumed to be known, as a priori information. 相似文献