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81.
Ina Varfaj Andrea Carotti Luciano Mangiapelo Lina Cossignani Agnese Taticchi Antonio Macchiarulo Federica Ianni Roccaldo Sardella 《Molecules (Basel, Switzerland)》2022,27(22)
Two LC methods were developed for the achiral and chiral reversed-phase (RP) analysis of an amino acid (AA) pool in a food supplement, in compliance with the main paradigms of Green Chromatography. A direct achiral ion-pairing RP-HPLC method was optimized under gradient conditions with a water-ethanol (EtOH) eluent containing heptafluorobutyric acid (0.1%, v/v), to quantify the eight essential AAs (Ile, Leu, Lys, Met, Phe, Thr, Trp, and Val) contained in the food supplement. Thus, the usually employed acetonitrile was profitably substituted with the less toxic and more benign EtOH. The method was validated for Leu and Phe. The chiral LC method performed with a teicoplanin chiral stationary phase was developed with a water-EtOH (60:40, v/v) eluent with 0.1%, v/v acetic acid. The enantioselective analysis was carried out without any prior derivatization step. Both developed methods performed highly for all eight AAs and revealed that: (i) the content of six out of eight AAs was consistent with the manufacturer declaration; (ii) only L-AAs were present. Furthermore, it was demonstrated that a two-dimensional achiral–chiral configuration is possible in practice, making it even more environmentally sustainable. A molecular modelling investigation revealed interesting insights into the enantiorecognition mechanism of Lys. 相似文献
82.
Rosa Sparaco Ewa Kdzierska Agnieszka A. Kaczor Anna Bielenica Elisa Magli Beatrice Severino Angela Corvino Ewa Gibua-Tarowska Jolanta H. Kotliska Giorgia Andreozzi Paolo Luciano Elisa Perissutti Francesco Frecentese Marcello Casertano Anna Leniak Magdalena Bujalska-Zadrony Magorzata Ozibo Raffaele Capasso Vincenzo Santagada Giuseppe Caliendo Ferdinando Fiorino 《Molecules (Basel, Switzerland)》2022,27(19)
A new series of 5-norbornene-2-carboxamide derivatives was prepared and their affinities to the 5-HT1A, 5-HT2A, and 5-HT2C receptors were evaluated and compared to a previously synthesized series of derivatives characterized by exo-N-hydroxy-5-norbornene-2,3-dicarboximidenucleus, in order to identify selective ligands for the above-mentioned subtype receptors. Arylpiperazines represents one of the most important classes of 5-HT1AR ligands, and recent research concerning new derivatives has been focused on the modification of one or more portions of such pharmacophore. The combination of structural elements (heterocyclic nucleus, propyl chain and 4-substituted piperazine), known to be critical to the affinity to 5-HT1A receptors, and the proper selection of substituents led to compounds with high specificity and affinity towards serotoninergic receptors. The most active compounds were selected for further in vivo assays to determine their functional activity. Finally, to rationalize the obtained results, molecular docking studies were performed. The results of the pharmacological studies showed that Norbo-4 and Norbo-18 were the most active and promising derivatives for the serotonin receptor considered in this study. 相似文献
83.
84.
Luciano De Vito 《Archive for Rational Mechanics and Analysis》1959,3(1):60-81
Memoria presentata da G. Fichera 相似文献
85.
Ramn Rodrigo Catalina Retamal Denisse Schupper Diego Vergara-Hernndez Sarmistha Saha Elisabetta Profumo Brigitta Buttari Luciano Saso 《Molecules (Basel, Switzerland)》2022,27(8)
Ischemia-reperfusion myocardial damage is a paradoxical tissue injury occurring during percutaneous coronary intervention (PCI) in acute myocardial infarction (AMI) patients. Although this damage could account for up to 50% of the final infarct size, there has been no available pharmacological treatment until now. Oxidative stress contributes to the underlying production mechanism, exerting the most marked injury during the early onset of reperfusion. So far, antioxidants have been shown to protect the AMI patients undergoing PCI to mitigate these detrimental effects; however, no clinical trials to date have shown any significant infarct size reduction. Therefore, it is worthwhile to consider multitarget antioxidant therapies targeting multifactorial AMI. Indeed, this clinical setting involves injurious effects derived from oxygen deprivation, intracellular pH changes and increased concentration of cytosolic Ca2+ and reactive oxygen species, among others. Thus, we will review a brief overview of the pathological cascades involved in ischemia-reperfusion injury and the potential therapeutic effects based on preclinical studies involving a combination of antioxidants, with particular reference to resveratrol and quercetin, which could contribute to cardioprotection against ischemia-reperfusion injury in myocardial tissue. We will also highlight the upcoming perspectives of these antioxidants for designing future studies. 相似文献
86.
Martino L Virno A Pagano B Virgilio A Di Micco S Galeone A Giancola C Bifulco G Mayol L Randazzo A 《Journal of the American Chemical Society》2007,129(51):16048-16056
The complex between distamycin A and the parallel DNA quadruplex [d(TGGGGT)]4 has been studied by 1H NMR spectroscopy and isothermal titration calorimetry (ITC). To unambiguously assert that distamycin A interacts with the grooves of the quadruplex [d(TGGGGT)]4, we have analyzed the NMR titration profile of a modified quadruplex, namely [d(TGGMeGGT)]4, and we have applied the recently developed differential frequency-saturation transfer difference (DF-STD) method, for assessing the ligand-DNA binding mode. The three-dimensional structure of the 4:1 distamycin A/[d(TGGGGT)]4 complex has been determined by an in-depth NMR study followed by dynamics and mechanics calculations. All results unequivocally indicate that distamycin molecules interact with [d(TGGGGT)]4 in a 4:1 binding mode, with two antiparallel distamycin dimers that bind simultaneously two opposite grooves of the quadruplex. The affinity between distamycin A and [d(TGGGGT)]4 enhances ( approximately 10-fold) when the ratio of distamycin A to the quadruplex is increased. In this paper we report the first three-dimensional structure of a groove-binder molecule complexed to a DNA quadruplex structure. 相似文献
87.
88.
The Proceedings of the Conference on Organic Chemistry at Clusters and Surfaces will comprise Volume 3, Number 3 (September 1992); Volume 3, Number 4 (December 1992); and Volume 4, Number 1 (March 1993). 相似文献
89.
Luciano Cavalli 《Magnetic resonance in chemistry : MRC》1970,2(3):233-244
The 19F NMR spectra of the cis- ( 1 ) and the trans-isomer ( 2 ) of the 1,2-dichlorotetrafluorocyclopropane and that of the 1,1-dichlorotetrafluorocyclopropane ( 3 ) have been investigated at different temperatures and in several solvents. From chemical shift calculations the two geminal fluorines in the cis-isomer ( 1 ) could be assigned and on this basis the two vicinal coupling constants of 1 , Jtrans (ca. 140°) and Jcis (ca. 0°), were unequivocally distinguished. By frequency sweep double resonance Jtrans has been shown to be of opposite sign to Jgem, whereas for Jcis the situation has been found to be reversed. Therefore Jtrans is presumably negative and Jcis positive. Only the N(Jcis + Jtrans) value could be extracted from the vicinal coupling constant in the fragment ? CFCl? CFCl? could be evaluated. It has been noted that Jcis is more sensitive to changes in temperature than is Jtrans. The variations of Jcis and Jtrans induced by solvents are, on the contrary, small and irregular and no correlation with the dielectric constant of the medium has been noted. The different temperature dependence of Jcis and Jtrans can be useful for assigning the vicinal F? F coupling constants in cyclopropane derivatives and also for defining their signs. This method was applied to the coupling constants extracted from the 13C satellite spectrum of isomer 3 . The coupling constants results were compared with some literature data already known, and some rationalisation and correlations from the trends was attempted. 相似文献
90.
Roberto Rossi Andrea Marchi Adriano Duatti Luciano Magon Plinio Di Bernardo 《Transition Metal Chemistry》1985,10(4):151-153
Summary The rhenium(V) imido-complexes [Re(NR)Cl3(PPh3)2] have been obtained by heating the rhenium(V) derivative [ReOCl3(PPh3)2] with RNHCHNR R = Ph (1a), p-MeC6H4 (1b), p-ClC6H4 (1c) andp-FC6H4 (1d) in THF under reflux. [Re(NR)Cl3(PPh3)2] (R =p-MeQ6H4) has also been obtained by heating the rhenium(III)-triazenido complex [ReCl2(RN
N
NR)(PPh3)2] in CCl4 under reflux. 相似文献