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141.
The aim of this study was to investigate the interaction between nitric oxide (NO) and acetylcholine (ACh) in penicillin-induced experimental epilepsy. Adult male Wistar rats weighing 220 ± 35 g were used in the experiments. The epileptiform activity was induced by microinjection of penicillin (200 IU/1 μl) into the left sensorymotor cortex. Electrocorticogram was recorded by using Ag/AgCl ball electrodes. Sodium nitroprusside (SNP), a NO donor, given intracortically 30 min after penicillin significantly reduced the spike frequency whereas ACh increased the epileptiform activity for 5 min. Atropine, an antagonist for muscarinic receptors, was given intracortically 30 min after penicillin and did not significantly affect epileptiform activity for 30 min. SNP given after atropine significantly suppressed the epileptiform activity. ACh given 10 min after Nω-nitro-L: -arginine methyl ester (L-NAME), a nonspecific nitric oxide synthase inhibitor, did not have a significant effect on spike frequency. When ACh and SNP were administered together, penicillin induced epileptiform activity and spike frequency were significantly suppressed from the 10th minute onwards. It can be concluded that ACh increases the penicillin-induced epileptiform activity while co-administration of ACh and SNP produces a potent anticonvulsant effect as compared to SNP alone. 相似文献
142.
Oh RS Pan WC Yalcin A Zhang H Guilarte TR Hotamisligil GS Christiani DC Lu Q 《The Journal of biological chemistry》2012,287(8):6025-6034
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Md. Abdullahil Baque Abdullah Elgirban Eun-Jung Lee Kee-Yoeup Paek 《Acta Physiologiae Plantarum》2012,34(2):405-415
The effect of initial sucrose concentration was investigated in root suspension cultures of Morinda citrifolia to improve root growth and secondary metabolites production, i.e. anthraquinone, phenolics and flavonoids. Besides, oxidative
stress level, antioxidant enzymes activity and membranes damage under different sucrose concentration were estimated. A 5%
sucrose supply was shown to be optimal for the production of root dry mass, but higher sucrose concentrations of 7–9% inhibited
the accumulation of root dry weight (DW). However, the maximum production of anthraquinone (251.89 g L−1 DW), phenolics (165.14 g L−1 DW) and flavonoids (163.56 g L−1 DW) were achieved at 1% sucrose-treated culture, which may be a source carbon skeletons for secondary metabolism. At the
same time was observed low oxidative damage, which could be associated with high levels of secondary metabolites and the increased
activity of catalase. Although, catalase (CAT) activity were stimulated at 7–9% sucrose-treated cultures, high accumulation
of hydrogen peroxide (H2O2) and peroxidation of lipid (MDA) was induced. The observed high activity of CAT and guaiacol peroxidase (G-POD) were not
sufficient enough to mitigate the toxic effect of H2O2. 相似文献
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The Naturally occurring novel cyclohexanonyl bromophenol 2(R)-2-(2,3,6-tribromo-4,5-dihydroxybenzyl)cyclohexanone (4) was synthesized as a racemic compound. Cyclohexylphenyl methane derivatives (10-17) with Br, OMe, CO, and OH were also obtained. Inhibition of four human carbonic anhydrase (hCA, EC 4.2.1.1) isozymes I, II, IV, and VI, with compounds 2-4, 8, and 10-26 was investigated. These compounds were found to be promising carbonic anhydrase inhibitors and some of them showed interesting inhibitory activity. Some of the compounds investigated here showed effective hCA inhibitory activity, and might be used as leads for generating novel carbonic anhydrase inhibitors which are valuable drug candidates for the treatment of glaucoma, epilepsy, gastric and duodenal ulcers, neurological disorders, and osteoporosis. 相似文献
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Balaydın HT Soyut H Ekinci D Göksu S Beydemir S Menzek A Sahin E 《Journal of enzyme inhibition and medicinal chemistry》2012,27(1):43-50
(2-Bromo-3,4-dimethoxyphenyl) (3,4-dimethoxyphenyl)methanone (10) and its derivatives with Br, one dibromide and isomeric three tribromides, were synthesized. Demethylation of these compounds afforded a series of new bromophenols. Inhibition of human cytosolic carbonic anhydrase II (hCA II) isozyme by these new bromophenols and naturally occurring 3,4,6-tribromo-5-(2,5-dibromo-3,4-dihydroxybenzyl)benzene-1,2-diol (3), and 5,5'-methylenebis(3,4,6-tribromo-benzene-1,2-diol) (4) was investigated. The synthesized compounds showed carbonic anhydrase inhibitory capacities with IC(50) values in the range of 0.7-372 μM against hCA II. Some bromophenols investigated here showed effective hCA II inhibitory activity and might be used as leads for generating novel carbonic anhydrase inhibitors which are valuable drug candidates for the treatment of glaucoma, epilepsy, gastric and duodenal ulcers, neurological disorders, or osteoporosis. 相似文献
150.
Aruna Govindaraju Alper Uzun LaShonda Robertson Mehmet O Atli Abdullah Kaya Einko Topper Elizabeth A Crate James Padbury Andy Perkins Erdogan Memili 《Reproductive biology and endocrinology : RB&E》2012,10(1):1-10