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621.
Suppression of HIF-prolyl hydroxylase (PHD) activity by small-molecule inhibitors leads to the stabilization of hypoxia inducible
factor and has been recognized as promising drug target for the treatment of ischemic diseases. In this study, pharmacophore-based
virtual screening and molecular docking approaches were concurrently used with suitable modifications to identify target-specific
PHD inhibitors with better absorption, distribution, metabolism, and excretion properties and to readily minimize false positives
and false negatives. A customized method based on the active site information of the enzyme was used to generate a pharmacophore
hypothesis (AAANR). The hypothesis was validated and utilized for chemical database screening and the retrieved hit compounds
were subjected to molecular docking for further refinement. AAANR hypothesis comprised three H-bond acceptor, one negative
ionizable group and one aromatic ring feature. The hypothesis was validated using decoy set with a goodness of fit score of
2 and was used as a 3D query for database screening. After manual selection, molecular docking and further refinement based
on the molecular interactions of inhibitors with the essential amino acid residues, 18 hits with good absorption, distribution,
metabolism, and excretion (ADME) properties were selected as excellent PHD inhibitors. The best pharmacophore hypothesis,
AAANR, contains chemical features required for the effective inhibition of PHD. Using AAANR, we have identified 18 potential
and diverse virtual leads, which can be readily evaluated for their potency as novel inhibitors of PHD. It can be concluded
that the combination of pharmacophore, molecular docking, and manual interpretation approaches can be more successful than
the traditional approach alone for discovering more effective inhibitors. 相似文献
622.
Katharigatta N. Venugopala Pottathil Shinu Christophe Tratrat Pran Kishore Deb Raquel M. Gleiser Sandeep Chandrashekharappa Deepak Chopra Mahesh Attimarad Anroop B. Nair Nagaraja Sreeharsha Fawzi M. Mahomoodally Michelyne Haroun Mahmoud Kandeel Syed Mohammed Basheeruddin Asdaq Viresh Mohanlall Nizar A. Al-Shari Mohamed A. Morsy 《Molecules (Basel, Switzerland)》2022,27(9)
Alteration of insect growth regulators by the action of inhibitors is becoming an attractive strategy to combat disease-transmitting insects. In the present study, we investigated the larvicidal effect of 1,2,3-triazolyl-pyrimidinone derivatives against the larvae of the mosquito Anopheles arabiensis, a vector of malaria. All compounds demonstrated insecticidal activity against mosquito larvae in a dose-dependent fashion. A preliminary study of the structure–activity relationship indicated that the electron-withdrawing substituent in the para position of the 4-phenyl-pyrimidinone moiety enhanced the molecules’ potency. A docking study of these derivatives revealed favorable binding affinity for the sterol carrier protein-2 receptor, a protein present in the intestine of the mosquito larvae. Being effective insecticides against the malaria-transmitting Anopheles arabiensis, 1,2,3-triazole-based pyrimidinones represent a starting point to develop novel inhibitors of insect growth regulators. 相似文献
623.
ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option. 相似文献
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Prof. Mahesh K. Lakshman 《Chemical record (New York, N.Y.)》2023,23(1):e202200182
Several naturally occurring purine and pyrimidine nucleosides contain an amide linkage as part of the heterocyclic aglycone. Enolization of the amide and conversion to leaving groups at the amide carbon atom permits base modification by addition-elimination types of processes. Although a number of methods have been developed over the years for accomplishing such conversions, the present Personal Account describes efforts from the Lakshman laboratories. Facile activation of the amido groups in nucleobases can be achieved with peptide-coupling agents. Subsequent reaction with nucleophiles then accomplishes the base modifications. In many cases, the activation and displacement steps can be done as two-step, one-pot processes, whereas in other cases, discrete storable activated nucleosides can be isolated for subsequent displacement reactions. Using such an approach a wide range of nucleoside base modifications is readily achievable. In many instances, mechanistic investigations have been conducted so as to understand the activation process. 相似文献
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Ebin Sebastian Mahesh Hariharan 《Angewandte Chemie (International ed. in English)》2023,62(12):e202216482
We report a long-lived charge-separated state in a chromophoric pair ( DC-PDI2 ) that uniquely integrates the advantages of fundamental processes of photosynthetic reaction centers: i) Symmetry-breaking charge-separation (SB-CS) and ii) Marcus-inverted-region dependence. The near-orthogonal bichromophoric DC-PDI2 manifests an ultrafast evolution of the SB-CS state with a time constant of =0.35±0.02 ps and a slow charge recombination (CR) kinetics with =4.09±0.01 ns in ACN. The rate constant of CR of DC-PDI2 is 11 686 times slower than SB-CS in ACN, as the CR of the PDI radical ion-pair occurs in the deep inverted region of the Marcus parabola ( >λ). In contrast, an analogous benzyloxy (BnO)-substituted DC-BPDI2 showcases a ≈10-fold accelerated CR kinetics with lowering to ≈1536 in ACN, by virtue of a decreased CR driving force. The present investigation demonstrates a control of molecular engineering to tune the energetics and kinetics of the SB-CS material, which is essential for next-generation optoelectronic devices. 相似文献
630.
The measurement of electrical conductivity for the investigation of the number of water molecules present in the mixed crystals of barium copper oxalate and barium ammonium oxalate lattice have been carried out in the temperature range 30 to 450 °C. The dehydration temperature and the number of water molecules removed out of the structure at a particular temperature is estimated from the sharp increase in conductivity at these points. The almost steep increase of conductivity is attributed to the increase in the number of mobile charge carriers H+ and OH– ions generated from the escaping water molecules. The study of electrical conductivity in association with the thermal behaviour has been used to understand the mechanism of conduction. 相似文献