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Zhang J Comotti M Schüth F Schlögl R Su DS 《Chemical communications (Cambridge, England)》2007,(19):1916-1918
Fresh commercial carbon nanotubes (CNTs) containing residual Co or Fe nanoparticles are highly active for NH3 decomposition while the microstructure of CNTs remains unchanged. The catalysts are promising for elimination of NH3 from coal gasification stream and for production of H2 from NH3. 相似文献
995.
Peddibhotla S Dang Y Liu JO Romo D 《Journal of the American Chemical Society》2007,129(40):12222-12231
The identification of "druggable" targets is an immediate opportunity and challenge in the post-genomic era. Natural products are enduring tools for basic cellular studies and leads for identifying medically relevant protein targets. However, their use for these studies is often hampered by limited quantities and a lack of selective and mild monofunctionalization reactions. The development of selective methods that could simultaneously equip the natural product with a reactive group for subsequent conjugation to reporter tags and provide important structure-activity relationship (SAR) information, requiring only a knowledge of functional groups present in the natural product, could significantly decrease the time between bioactive natural product isolation and target identification. Herein, we report such a strategy that enables simultaneous arming and SAR studies of alcohol-containing natural products involving both chemo- and site-selective ("chemosite" selective) and site-nonselective O-H insertion reactions with rhodium carbenoids derived from alkynyl diazo acetates. This strategy was applied to a diverse set of natural products, and general guidelines for predicting chemosite selectivity were formulated. A subsequent Sharpless-Hüisgen [3 + 2] cycloaddition reaction with the appended alkyne allows for attachment of a variety of reporter tags. Using this strategy, we synthesized a novel FK506-biotin conjugate that enabled pull-down of the entire "immunosuppressive complex" including FKBP12, calcineurins A and B, and calmodulin. In addition, the potential for a chemoselective but site-nonselective process was shown with both gibberellic acid methyl ester and brefeldin A using only achiral rhodium catalysts. 相似文献
996.
Erion MD Dang Q Reddy MR Kasibhatla SR Huang J Lipscomb WN van Poelje PD 《Journal of the American Chemical Society》2007,129(50):15480-15490
AMP binding sites are commonly used by nature for allosteric regulation of enzymes controlling the production and metabolism of carbohydrates and lipids. Since many of these enzymes represent potential drug targets for metabolic diseases, efforts were initiated to discover AMP mimics that bind to AMP-binding sites with high affinity and high enzyme specificity. Herein we report the structure-guided design of potent fructose 1,6-bisphosphatase (FBPase) inhibitors that interact with the AMP binding site on FBPase despite their structural dissimilarity to AMP. Molecular modeling, free-energy perturbation calculations, X-ray crystallography, and enzyme kinetic data guided our redesign of AMP, which began by replacing the 5'-phosphate with a phosphonic acid attached to C8 of the adenine base via a 3-atom spacer. Additional binding affinity was gained by replacing the ribose with an alkyl group that formed van der Waals interactions with a hydrophobic region within the AMP binding site and by replacing the purine nitrogens N1 and N3 with carbons to minimize desolvation energy expenditures. The resulting benzimidazole phosphonic acid, 16, inhibited human FBPase (IC50 = 90 nM) 11-fold more potently than AMP and exhibited high specificity for the AMP binding site on FBPase. 16 also inhibited FBPase in primary rat hepatocytes and correspondingly resulted in concentration-dependent inhibition of the gluconeogenesis pathway. Accordingly, these results suggest that the AMP site of FBPase may represent a potential drug target for reducing the excessive glucose produced by the gluconeogenesis pathway in patients with type 2 diabetes. 相似文献
997.
Zhou H Dang H Yi JH Nanci A Rochefort A Wuest JD 《Journal of the American Chemical Society》2007,129(45):13774-13775
998.
Rahn T Nguyen VT Dang TH Ahmed Z Methling K Lalk M Fischer C Spannenberg A Langer P 《The Journal of organic chemistry》2007,72(6):1957-1961
A variety of 1,3,5-tricarbonyl derivatives were prepared by reaction of 1,3-bis(silyl enol ethers) with acid chlorides under mild conditions. This includes reactions of both aromatic and aliphatic acid chlorides and bis(acid chlorides). The yields vary depending on the type of acid chloride employed. 相似文献
999.
Zhou Shujia Yan Chengrong Dang Yunfei Cao Xuefang Wei Zhixian 《Journal of nanoparticle research》2021,23(9):1-28
Journal of Nanoparticle Research - The studies on the utilisation of supercritical fluids (SCFs) in processing chemicals and materials have garnered significant attention in the past two decades.... 相似文献
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