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221.
Nourhan M. Abd El-Aziz Ibrahim Khalifa Amira M. G. Darwish Ahmed N. Badr Huda Aljumayi El-Sayed Hafez Mohamed G. Shehata 《Molecules (Basel, Switzerland)》2022,27(9)
COVID-19 is still a global pandemic that has not been stopped. Many traditional medicines have been demonstrated to be incredibly helpful for treating COVID-19 patients while fighting the disease worldwide. We introduced 10 bioactive compounds derived from traditional medicinal plants and assessed their potential for inhibiting viral spike protein (S-protein), Papain-like protease (PLpro), and RNA dependent RNA polymerase (RdRp) using molecular docking protocols where we simulate the inhibitors bound to target proteins in various poses and at different known binding sites using Autodock version 4.0 and Chimera 1.8.1 software. Results found that the chicoric acid, quinine, and withaferin A ligand strongly inhibited CoV-2 S -protein with a binding energy of −8.63, −7.85, and −7.85 kcal/mol, respectively. Our modeling work also suggested that curcumin, quinine, and demothoxycurcumin exhibited high binding affinity toward RdRp with a binding energy of −7.80, −7.80, and −7.64 kcal/mol, respectively. The other ligands, namely chicoric acid, demothoxycurcumin, and curcumin express high binding energy than the other tested ligands docked to PLpro with −7.62, −6.81, and −6.70 kcal/mol, respectively. Prediction of drug-likeness properties revealed that all tested ligands have no violations to Lipinski’s Rule of Five except cepharanthine, chicoric acid, and theaflavin. Regarding the pharmacokinetic behavior, all ligand predicted to have high GI-absorption except chicoric acid and theaflavin. At the same way chicoric acid, withaferin A, and withanolide D predicted to be substrate for multidrug resistance protein (P-gp substrate). Caffeic acid, cepharanthine, chicoric acid, withaferin A, and withanolide D also have no inhibitory effect on any cytochrome P450 enzymes. Promisingly, chicoric acid, quinine, curcumin, and demothoxycurcumin exhibited high binding affinity on SARS-CoV-2 target proteins and expressed good drug-likeness and pharmacokinetic properties. Further research is required to investigate the potential uses of these compounds in the treatment of SARS-CoV-2. 相似文献
222.
Ahmed Marwa F. Khalifa Amany S. Eed Emad M. 《Russian Journal of General Chemistry》2021,91(12):2497-2505
Russian Journal of General Chemistry - Novel quinazoline derivatives have been designed, synthesized and tested for cytotoxic activity against HCT116, and MCF-7 cell lines. The preliminary data... 相似文献
223.
In this article, we consider the drift parameter estimation problem for the nonergodic Ornstein-Uhlenbeck process defined as d X_t= θX_tdt + dG_t, t ≥ 0 with an unknown parameter θ 0, where G is a Gaussian process. We assume that the process {X_t, t ≥ 0} is observed at discrete time instants t_1 = ?_n, ···, t_n= n?_n, and we construct two least squares type estimators ■ and ■ for θ on the basis of the discrete observations {X_(t_i), i = 1, ···, n}as n →∞. Then, we provide sufficient conditions, based on properties of G, which ensure that ■ and ■ are strongly consistent and the sequences n?n~(1/2)(■-θ) and n?n~(1/2)(■-θ)are tight. Our approach offers an elementary proof of [11], which studied the case when G is a fractional Brownian motion with Hurst parameter H ∈(1/2, 1). As such, our results extend the recent findings by [11] to the case of general Hurst parameter H ∈(0, 1). We also apply our approach to study subfractional Ornstein-Uhlenbeck and bifractional Ornstein-Uhlenbeck processes. 相似文献
224.
Khalifa N. M. Haiba M. E. Afifi A. H. El-Moez S. I. Abd Soliman A. M. 《Russian Journal of General Chemistry》2022,92(9):1728-1736
Russian Journal of General Chemistry - The reaction between different arylhydrazones and ninhydrin (= indene-1,2-3-trione) in acetonitrile at room temperature is described to produce novel... 相似文献
225.
Naglah A. M. Amr A. E. Khalifa N. M. Al-Omar M. A. 《Russian Journal of General Chemistry》2015,85(12):2833-2838
Russian Journal of General Chemistry - A series of octa bridged peptide and macrocyclic pentapeptide Schiff base derivatives were synthesized from tetrapeptide hydrazide and macrocyclic... 相似文献
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227.
Hesham Fahmy Jordan K. Zjawiony Sherief Khalifa Frank R. Fronczek 《Acta Crystallographica. Section C, Structural Chemistry》2003,59(2):o85-o87
The title molecule, 2(R)‐[(1E,3E,7S,8S,11E,13R)‐13‐hydroxy‐4,8,12‐trimethyl‐7,8‐epoxycyclotetradeca‐1,3,11‐trien‐1‐yl]propane‐1,2‐diol, C20H32O4, is a semi‐synthetic analog of sarcophine, the natural cembranoid of marine origin, isolated from the soft coral Sarcophyton glaucum. The conformation of the 14‐membered ring differs substantially from that of sarcophine. The two OH groups of the propane‐1,2‐diol moiety form an unusual weak intramolecular hydrogen bond with an O⋯O distance of 2.788 (2) Å, and the molecules are linked into double chains by intermolecular hydrogen bonds with O⋯O distances of 2.772 (2) and 2.849 (2) Å. 相似文献
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