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181.
Isolation,Synthesis and AChE Inhibitory Potential of Some Novel Cinnamyl Esters of Taraxerol,the Major Metabolite of the Mangrove Bruguiera cylindrica
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Vidyan Nithyamol Kalappurakkal Dwaipayan Bhattacharya Sumana Chakravarty Mallavadhani Venkata Uppuluri 《化学与生物多样性》2018,15(4)
Systematic chemical screening of the leaves of Bruguiera cylindrica, the tree mangrove of Rhizophoraceae family, afforded five single and pure compounds. The structures of the isolated compounds were established by their spectroscopic data as taraxerol ( 1 ), 3β‐(E)‐coumaroyltaraxerol ( 2 ), 3β‐(Z)‐coumaroyltaraxerol ( 3 ), β‐sitosterol ( 4 ), and eicosanol ( 5 ). In view of significant accumulation and interesting biological activities, taraxerol ( 1 ) was chemically transformed to synthesize a series of ten cinnamyl esters in very good to excellent yields. The synthesized analogues along with the parent compound were evaluated for their AChE inhibitory potential, BBB permeability and cytotoxicity against Neuro 2A cell line. Among the tested samples, compound 9 showed promising AChE inhibition with significantly low IC50 values, low cytotoxicity and high BBB permeability. Hence, compound 9 can be considered as a lead molecule for further development as potent AChE inhibitor. 相似文献
182.
Nirmal Chakravarty 《The Journal of cell biology》1965,25(2):123-128
Glycolytic activity of rat peritoneal mast cells has been measured by the Cartesian ampulla diver technique. The rates of anaerobic glycolysis, expressed as CO2 expelled from a bicarbonate medium, are 1.70 x 10-6 µl and 1.43 x 10-6 µl per cell per hour with and without glucose, respectively. The aerobic glycolysis rate in the presence of glucose, assuming the respiratory quotient to be 1, is 0.93 x 10-6 µl CO2 per cell per hour. It is pointed out that the anaerobic and non-respiratory aerobic carbon dioxide production by mast cells is much higher than the respiratory oxygen uptake reported previously. These values have been interpreted in terms of glucose utilization. 相似文献
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184.
Elavarasan Subramani Mainak Dutta Manivannan Jothiramajayam Mamata Joshi Sudha Srivastava Anita Mukherjee Baidyanath Chakravarty Koel Chaudhury 《Metabolomics : Official journal of the Metabolomic Society》2016,12(6):99
Introduction
Genital tuberculosis (GTB) in women is one of the common causes of infertility in emerging countries. As an intracellular pathogen, Mycobacterium tuberculosis in the endometrium significantly alters the host metabolism in dormant GTB cases. Nuclear magnetic resonance (NMR) based metabolic profiling has emerged as a useful tool for identification of biomarkers in biological fluids.Objective
To investigate NMR based serum metabolic profile of dormant GTB women as compared to controls.Methods
Dormant GTB women (n = 26) and unexplained infertile women (controls; n = 26), healthy proven fertile women undergoing voluntary sterilization (n = 25) and women undergoing recurrent spontaneous miscarriage (RSM) (n = 27) were included in the study. 700 MHz proton NMR spectra of serum collected from these patients were recorded. Multivariate analysis including principal component analysis, partial least squares discriminant analysis and orthogonal projection to latent structure-discriminant analysis was applied to all the spectra. Association of dysregulated serum metabolites with our earlier findings related to altered endometrial tissue metabolites in dormant GTB women was studied using multiple correlation analysis.Results
This study indicates a clear metabolic differentiation between women with dormant GTB and controls. Metabolites including 3-hydroxybutyrate, succinate, citrate, acetate, l-glutamine, l-lysine, glutamate, l-threonine and 1-methyl histidine were found to be significantly upregulated in serum of women with dormant GTB compared with controls. Pearson’s correlation analysis showed a significant correlation between the expression of endometrial tissue and serum metabolites.Conclusions
The set of identified metabolites may be considered as candidate markers for the diagnosis of dormant GTB and help clinicians in early therapeutic management.185.
186.
187.
The title compounds were made by reacting bis(diphenylphosphino)methane (dppm) with reduced solutions of OsCl64? and Ru2OCl104?. The crystal and molecular structures of these compounds have been determined form three-dimensional X-ray study. The cis-isomers crystallize with one CHCl3 per molecule of the complex. All three compounds crystallize in the monoclinic space group P21/n with unit cell dimensions as follows: Cis-OsCl2(dppm)2·CHCl3: a = 13.415(4) Å, b = 22.859(4) Å, c = 16.693(3) Å, β = 105.77(3)°, V = 4926(3) Å3, Z = 4. cis-RuCl2(dppm)2·CHCl3: a = 13.442(3) Å, b = 22.833(7) Å, c = 16.750(4) Å, β = 105.53(2)°, V = 4953(3) Å3, Z = 4. trans-RuCl2(dppm)2: a = 11.368(7) Å, b = 10.656(6) Å, c = 18.832(12) Å; β = 103.90(6)°, V = 2213(7) Å3; Z = 2. The structures were refined to R = 0.044 (Rw = 0.055) for cis-OsCl2(dppm)2·CHCl3; R = 0.065 (Rw = 0.079) for cis-RuCl2(dppm)2·CHCl3 and R = 0.028 (Rw = 0.038) for trans-RuCl2(dppm)2. The complexes are six coordinate with stable four-membered chelate rings. The PMP angle in the chelate rings is ca. 71° in each case. 相似文献
188.
Rao S He L Chakravarty S Ojima I Orr GA Horwitz SB 《The Journal of biological chemistry》1999,274(53):37990-37994
Photoaffinity labeling methods have allowed a definition of the sites of interaction between Taxol and its cellular target, the microtubule, specifically beta-tubulin. Our previous studies have indicated that [(3)H]3'-(p-azidobenzamido)Taxol photolabels the N-terminal 31 amino acids of beta-tubulin (Rao, S., Krauss, N. E., Heerding, J. M., Swindell, C. S., Ringel, I., Orr, G. A., and Horwitz, S. B. (1994) J. Biol. Chem. 269, 3132-3134) and [(3)H]2-(m-azidobenzoyl)Taxol photolabels a peptide containing amino acid residues 217-233 of beta-tubulin (Rao, S., Orr, G. A., Chaudhary, A. G., Kingston, D. G. I., and Horwitz, S. B. (1995) J. Biol. Chem. 270, 20235-20238). The site of photoincorporation of a third photoaffinity analogue of Taxol, [(3)H]7-(benzoyldihydrocinnamoyl) Taxol, has been determined. This analogue stabilizes microtubules polymerized in the presence of GTP, but in contrast to Taxol, does not by itself enhance the polymerization of tubulin to its polymer form. CNBr digestion of [(3)H]7-(benzoyldihydrocinnamoyl)Taxol-labeled tubulin, with further arginine-specific cleavage by clostripain resulted in the isolation of a peptide containing amino acid residues 277-293. Amino acid sequence analysis indicated that the photoaffinity analogue cross-links to Arg(282) in beta-tubulin. Advances made by electron crystallography in understanding the structure of the tubulin dimer have allowed us to visualize the three sites of photoincorporation by molecular modeling. There is good agreement between the binding site of Taxol in beta-tubulin as determined by photoaffinity labeling and electron crystallography. 相似文献
189.
Molecular adaptations underlying susceptibility and resistance to social defeat in brain reward regions 总被引:4,自引:0,他引:4
Krishnan V Han MH Graham DL Berton O Renthal W Russo SJ Laplant Q Graham A Lutter M Lagace DC Ghose S Reister R Tannous P Green TA Neve RL Chakravarty S Kumar A Eisch AJ Self DW Lee FS Tamminga CA Cooper DC Gershenfeld HK Nestler EJ 《Cell》2007,131(2):391-404
While stressful life events are an important cause of psychopathology, most individuals exposed to adversity maintain normal psychological functioning. The molecular mechanisms underlying such resilience are poorly understood. Here, we demonstrate that an inbred population of mice subjected to social defeat can be separated into susceptible and unsusceptible subpopulations that differ along several behavioral and physiological domains. By a combination of molecular and electrophysiological techniques, we identify signature adaptations within the mesolimbic dopamine circuit that are uniquely associated with vulnerability or insusceptibility. We show that molecular recapitulations of three prototypical adaptations associated with the unsusceptible phenotype are each sufficient to promote resistant behavior. Our results validate a multidisciplinary approach to examine the neurobiological mechanisms of variations in stress resistance, and illustrate the importance of plasticity within the brain's reward circuits in actively maintaining an emotional homeostasis. 相似文献
190.
Raboisson P Lenz O Lin TI Surleraux D Chakravarty S Scholliers A Vermeiren K Delouvroy F Verbinnen T Simmen K 《Bioorganic & medicinal chemistry letters》2007,17(7):1843-1849
Screening of a focused library of TGF beta kinase inhibitors in the cellular HCV replicon model with luciferase read out yielded a number of low micromolar HCV inhibitors. Medicinal chemistry driven optimization resulted in the discovery of 4-[2-(5-bromo-2-fluoro-phenyl)pteridin-4-ylamino]-N-[3-(2- oxopyrrolidin-1-yl)propyl]nicotinamide 36 with a replicon EC(50) of 64nM, associated with a selective kinase inhibitory profile for human JNK kinases 2 and 3 as well as VEGFR-1, 2, and 3 kinases. Moreover, 36 showed an advantageous PK profile in mice. Experiments performed using different replicon constructs suggest that this series of kinase inhibitors might mediate their effect through the HCV non-structural protein 5A (NS5A). 相似文献