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51.
52.
Vydyula Pavan Kumar Perepogu Arun Kumar Iragavarapu Suryanarayana Yadavalli Venkata Durga Nageswar Kakulapati Rama Rao 《Helvetica chimica acta》2007,90(9):1697-1704
The two pyrrolidinylidenesulfamido‐modified β‐cyclodextrins (β‐CDs) 3 and 4 were prepared and studied for chiral discrimination of the enantiomers (R)‐ and (S)‐ 1 of zolmitriptan. The pyrrolidinylidenesulfamido spacer improved the chiral discrimination and binding abilities of these modified cyclodextrins. The hosts 3 and 4 showed higher selectivity for (S)‐ 1 . The association constants (Table) and enantioselectivity factors were calculated for the complexes of (R)‐ and (S)‐ 1 with the β‐CDs 2 – 4 . The formation of host?guest complexes was confirmed by 1H‐NMR studies. 相似文献
53.
Structure Activity Relationship Studies around DB18, a Potent and Selective Inhibitor of CLK Kinases
Dabbugoddu Brahmaiah Anagani Kanaka Durga Bhavani Pasula Aparna Nangunoori Sampath Kumar Hlne Solhi Rmy Le Guevel Blandine Baratte Thomas Robert Sandrine Ruchaud Stphane Bach Surender Singh Jadav Chada Raji Reddy Paul Mosset Nicolas Gouault Nicolas Levoin Ren Gre 《Molecules (Basel, Switzerland)》2022,27(19)
Three series of our lead CLK1 inhibitor DB18 have been designed, synthetized and tested against CLKs and DYRK1A kinases. Their cytotoxicity was subsequently measured on seven representative cancer cell lines. Guided by docking experiments, we focused on the less constrained part of the scaffold, and showed that drastically different substituents can be tolerated here. This work ended with the discovery of another promising derivative 12g, with IC50 = 0.004 µM in the inhibition of HsCLK1 and IC50 = 3.94 µM for the inhibition of HsDYRK1A. The SAR results are discussed in the light of extensive molecular modeling analyses. Finally, a kinome scan (463 human kinases) confirmed the outstanding selectivity of our lead compound DB18, suggesting that this scaffold is of prominent interest for selective CLK inhibitors. Altogether, these results pave the way for the development of inhibitors with novel selectivities in this family of kinases. 相似文献
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Molecular structure, and phase behaviour of 2-Cyano-N-[4-(4-n-pentyloxybenzoyloxy)-benzylidene] aniline (CPBBA) has been reported with respect to translational and orientational motions. The atomic net charge and dipole moment components at each atomic centre have been evaluated using the complete neglect differential overlap (CNDO/2) method. The modified Rayleigh–Schrodinger perturbation theory along with multicentered–multipole expansion method has been employed to evaluate the long-range intermolecular interactions, while a ‘6-exp’ potential function has been assumed for short-range interactions. The interaction energy values obtained through these computations have been used as input to calculate the configurational probability at room temperature (300 K), and nematic–isotropic transition temperature (396.5 K). On the basis of stacking, in-plane, and terminal interaction energy calculations, all possible geometrical arrangements between the molecular pairs have been considered. Molecular arrangements inside a bulk of materials have been discussed in terms of their relative order. Further, translational rigidity parameter has been estimated as a function of temperature to understand the phase behaviour of the compound. The present model is helpful to understand the effect of molecular motions on ordering, and phase behaviour of the mesogenic compounds. 相似文献
56.
Sabbavarapu Narayana Murthy Bandaru Madhav Yadavalli Venkata Durga Nageswar 《Helvetica chimica acta》2010,93(6):1216-1220
Substituted benzene‐1,2‐diamine reacted with various α‐keto esters at 50° under mild conditions for 15 min using H2O as reaction medium, providing a variety of 3‐substituted quinoxalinone derivatives in excellent yields. The reaction was instantaneous, and products were isolated by simple filtration. 相似文献
57.
Lakshmi Praveen P. Ajeetha N. Ojha Durga P. 《Russian Journal of General Chemistry》2009,79(10):2267-2271
Russian Journal of General Chemistry - A computational analysis of ordering in N-(4-n-alkoxy benzylidene)-4′-alkyl aniline ( n O m ) with n = 7, m = 6 carbon atoms in alkyl chain has been... 相似文献
58.
A. S. Pradeep G. J. Nagaraju P. Sarita A. Durga Prasada Rao B. Seetharami Reddy G. Bhagya Rao S. Bhuloka Reddy 《Journal of Radioanalytical and Nuclear Chemistry》2012,294(2):271-276
A number of essential trace elements play a major role in various metabolic pathways and in many diseases like autoimmune, neurological and psychiatric. This study is undertaken with an aim to evaluate the levels of different trace elements in the scalp hair samples of patients suffering from alcohol induced psychosis by particle induced X-ray emission technique (PIXE). It is observed that Fe (p?<?0.0005), Cu (p?<?0.001) are significantly higher in the hair samples of alcohol induced psychosis patients compared to those in normals while concentrations of Mn (p?<?0.005) and Zn (p?<?0.0001) are lower. The concentrations of Co and Ni in the hair samples are found to be in consonance with the concentrations in the normals. 相似文献
59.
Mendu Narender Majjigapu Somi Reddy Yadavalli Venkata Durga Nageswar Kakulapati Rama Rao 《Helvetica chimica acta》2007,90(6):1107-1111
A simple and mild procedure was developed for the first time for the C(3)‐selective ring opening of an aromatic 2,3‐epoxy alcohol, i.e., of trans‐3‐phenyloxirane‐2‐methanol ( 1 ), with sodium phenoxides or thiophenoxides (=benzenethiolates) 2 supported by β‐cyclodextrin in H2O at 50° to afford the corresponding 3‐(aryloxy)‐ or 3‐(arylthio)propane1,2‐diols 3 in excellent yields (Scheme, Table). 相似文献
60.
Rathna Durga R.S. Manian 《Tetrahedron letters》2006,47(43):7571-7574
A rapid synthesis of mono- and bis-tetrahydropyrazolo[4′,3′:5,6]thiopyrano[4,3-b]quinolines has been achieved by the reaction of aldimines derived from aromatic amines and S-prenylated aldehydes in acetonitrile with InCl3 as a catalyst, in excellent yields and short reaction times, under mild conditions. 相似文献