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排序方式: 共有621条查询结果,搜索用时 31 毫秒
611.
Umesh Kumar Kusum Kumari Shailesh N. Sharma Mahesh Kumar V. D. Vankar Rita Kakkar Vikram Kumar 《Colloid and polymer science》2010,288(8):841-849
In this work, tri-octyl phosphine/tri-octyl phosphine oxide (TOPO)-capped cadmium selenide (CdSe) quantum dots (QDs) of varied
sizes (5–9 nm), prepared by varying the input Cd:Se precursor ratio using chemical route, were dispersed in conducting polymer
matrices viz. poly[2-methoxy, 5-(2-ethyl-hexyloxy)-1,4-phenylene vinylene] (MEH-PPV) and poly(3-hexylthiophene) (P3HT). By
using a binary solvent mixture (pyridine–chloroform), homogeneous dispersion of CdSe nanocrystals in polymers (MEH-PPV, P3HT)
could be realized. The properties of the resulting dispersions could be tailored by the composition and concentration of QDs
in polymer. The emission and structural properties of polymer–CdSe nanocomposites are found to be dependent on the crystallite
size and morphology of CdSe nanocrystallites. An effective quenching of photoluminescence emission in the polymer nanocomposite
was observed for smaller CdSe quantum dots (size ∼6 nm) as compared to larger CdSe quantum dots (size ∼9 nm), thus ensuring
efficient charge transfer process across the polymer–CdSe interface in the former case. The incomplete quenching, particularly
for MEH-PPV:CdSe nanocomposites, could be as a result of insufficient coverage of polymers on the surface of CdSe nanocrystallites,
mainly due to phase segregation for TOPO-stripped CdSe nanocrystallites. The superior morphology and optical properties of
polymer nanocomposite (P3HT:CdSe QDs) could play a pivotal role for the realization of effective charge separation and transport
in hybrid solar cells. 相似文献
612.
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
613.
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
614.
P. Raghunatha Mohammed Naseeruddin Inamdar Syed Mohammed Basheeruddin Asdaq Mansour Almuqbil Abdullah R. Alzahrani Saleh I. Alaqel Mehnaz Kamal Firas Hamdan Alsubaie Walaa F. Alsanie Abdulhakeem S. Alamri Syed Imam Rabbani Mahesh Attimarad S. Mohan Majid Alhomrani 《Molecules (Basel, Switzerland)》2022,27(19)
Cardiovascular diseases are one of the major causes of mortalities worldwide. In the present research, new synthetic derivatives of thiazole were studied using isolated hearts and blood vessels of rats. The heart and thoracic aorta were tested with six new synthesized thiazole acetic acid derivatives (SMVA-10, SMVA-35, SMVA-40, SMVA-41, SMVA-42 and SMVA-60), and the data obtained were statistically analyzed and compared. Isolated rat hearts were used to record the changes in developed tension and heart rate, while thoracic aortas were used to measure the contractile response, before and after treatments. Analysis of the results indicated a significant (p < 0.01) increase in developed tension with the addition of SMVA-35, SMVA-40, SMVA-41 and SMVA-42, which was augmented in the presence of adrenaline without affecting the heart rate. On the other hand, acetylcholine significantly decreased the developed tension, which was significantly reversed (p < 0.01) in the presence of compounds (SMVA-35 and SMVA-60). However, in the presence of SMVA-35 and SMVA-40, acetylcholine-induced bradycardia was significantly (p < 0.01) reduced. Furthermore, only SMVA-42 induced a dose-dependent contractile response in the isolated blood vessel, which was abolished in the presence of prazosin. Therefore, it can be concluded that some of the new synthesized thiazole derivatives exhibited promising results by raising the developed tension without changing the heart rate or blood vessel function, which could be helpful in failing heart conditions. However, more research is required to fully comprehend the function, mechanism and effectiveness of the compounds. 相似文献
615.
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
616.
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618.
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
619.