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991.
The molecular diversity of the foregut bacterial community in the dromedary camel (Camelus dromedarius) in Central Australia was investigated through comparative analyses of 16S rRNA gene sequences prepared from the foregut contents of 12 adult feral camels fed on native vegetation. A total of 267 full-length 16S rRNA gene clones were examined, with 151 operational taxonomic units (OTUs) identified at a 99% species-level identity cut-off criterion. The prediction of actual diversity in the foregut of the dromedary camel using the Chaol approach was 238 OTUs, while the richness and evenness of the diversity estimated using Shannon index was 4.84. The majority of bacteria in the current study were affiliated with the bacterial phylum Firmicutes (67% of total clones) and were related to the classes Clostridia, Bacilli and Mollicutes, followed by the Bacteroidetes (25%) that were mostly represented by the family Prevotellaceae. The remaining phyla were represented by Actinobacteria, Chloroflexi, Cynophyta, Lentisphaerae, Planctomycetes, Proteobacteria and Sphirochaetes. Moreover, 11 clones of cultivated bacteria were identified as Brevundimonas sp., Butyrivibrio fibrisolvens, Prevotella sp. and Ruminococcus flavefaciens. The novelty in this foregut environment is remarkable where 97% of the OTUs were distantly related to any known sequence in the public database. 相似文献
992.
Haider A. J. Al Lawati Zeiyana M. Al Dahmani Fakhr Eldin O. Suliman Salma M. Z. Al Kindy Ali M. Al‐Lawati 《Luminescence》2011,26(6):762-767
A simple, rapid and sensitive method has been developed for the analysis of fexofenadine (FEX) in pharmaceutical formulations, using a tris(1,10‐phenanthroline)–ruthenium(II) [Ru(phen)32+] peroxydisulphate chemiluminescence (CL) system in a multichip device. Various parameters that influence the CL signal intensity were optimized. These included pH, flow rates and concentration of reagents used. Under optimum conditions, a linear calibration curve in the range 0.05–5.0 µg/mL was obtained. The detection limit was found to be 0.001 µg/mL. The procedure was applied to the analysis of FEX in pharmaceutical products and was found to be free from interference from concomitants usually present in these preparations. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
993.
Salma M. Z. Al‐Kindy Zahra Al‐Mafrigi Musa S. Shongwe Fakhr Eldin O. Suliman 《Luminescence》2011,26(6):462-470
A sensitive and selective spectrofluorimetric method has been developed for the rapid determination of aluminium. This method is based on the complex formation between aluminium and 2‐hydroxy‐1‐naphthylidene‐(8‐aminoquinoline) (HNAQ). The optimum conditions for the complex formation were a metal‐to‐ligand (M : L) stoichiometric ratio of 1:1, a pH of 5.5 and a 0.20 m acetate buffer. The fluorescence of the complex was monitored at an emission wavelength of 502 nm with excitation at 438 nm. Under these conditions, linear calibration curves were obtained in the ranges 0.05–1 and 1–5 ppm. The detection limit was 3.4 ppb for the former and 13.5 ppb for the latter. The maximum relative standard deviation of the method for an aluminium standard of 200 ppb was 1.5% (n = 5). This method was successfully applied for the determination of aluminium in drinking water, pharmaceutical antacid tablets and suspension samples. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
994.
Lettre G Palmer CD Young T Ejebe KG Allayee H Benjamin EJ Bennett F Bowden DW Chakravarti A Dreisbach A Farlow DN Folsom AR Fornage M Forrester T Fox E Haiman CA Hartiala J Harris TB Hazen SL Heckbert SR Henderson BE Hirschhorn JN Keating BJ Kritchevsky SB Larkin E Li M Rudock ME McKenzie CA Meigs JB Meng YA Mosley TH Newman AB Newton-Cheh CH Paltoo DN Papanicolaou GJ Patterson N Post WS Psaty BM Qasim AN Qu L Rader DJ Redline S Reilly MP Reiner AP Rich SS Rotter JI Liu Y Shrader P Siscovick DS 《PLoS genetics》2011,7(2):e1001300
Coronary heart disease (CHD) is the leading cause of mortality in African Americans. To identify common genetic polymorphisms associated with CHD and its risk factors (LDL- and HDL-cholesterol (LDL-C and HDL-C), hypertension, smoking, and type-2 diabetes) in individuals of African ancestry, we performed a genome-wide association study (GWAS) in 8,090 African Americans from five population-based cohorts. We replicated 17 loci previously associated with CHD or its risk factors in Caucasians. For five of these regions (CHD: CDKN2A/CDKN2B; HDL-C: FADS1-3, PLTP, LPL, and ABCA1), we could leverage the distinct linkage disequilibrium (LD) patterns in African Americans to identify DNA polymorphisms more strongly associated with the phenotypes than the previously reported index SNPs found in Caucasian populations. We also developed a new approach for association testing in admixed populations that uses allelic and local ancestry variation. Using this method, we discovered several loci that would have been missed using the basic allelic and global ancestry information only. Our conclusions suggest that no major loci uniquely explain the high prevalence of CHD in African Americans. Our project has developed resources and methods that address both admixture- and SNP-association to maximize power for genetic discovery in even larger African-American consortia. 相似文献
995.
Mohammed Al Bratty Yahya Hobani Julian A. T. Dow David G. Watson 《Metabolomics : Official journal of the Metabolomic Society》2011,7(4):542-548
Metabolomic profiling using hydrophilic interaction chromatography in combination with Fourier transform mass spectrometry
was used to study the effects of the xanthine oxidase inhibitor allopurinol on wild type Drosophila melanogaster. Allopurinol treatment phenocopied the rosy mutation causing an elevation in the levels of xanthine and hypoxanthine and
a fall in the levels of uric acid and allantoin. However, in addition there were some unexpected metabolic changes after treatment.
Ascorbic acid levels were undetectable, glutathione levels fell and glutathione disulphide levels rose, methionine S-oxide
levels rose and riboflavin levels fell. The origin of this oxidative stress was not immediately apparent; however, there was
a strong suggestion that it might be related to a fall in NADPH levels linked to a reduction in glucose-6-phosphate dehydrogenase
activity, resulting in reduced levels of some metabolites in the pentose phosphate pathway. In addition to producing oxidative
stress there were marked effects on tryptophan metabolism with most of the metabolites in the kynurenine pathway being lowered
by allopurinol treatment. The effects on the kynurenine pathway could be related to the established use of allopurinol in
treating schizophrenia. 相似文献
996.
In recent years, DNA barcoding has emerged as a powerful tool for species identification. We report an extended validation of a universal DNA mini-barcode for amplification of 130-bp COI segments from 23 specimens collected from a desert environment, including 11 reptiles, five mammals and seven birds. Besides the standard double-annealing protocol, we also tested a more stringent single-annealing protocol. The PCR success rate for the amplification of the mini-barcode region was: mammals (4/5), reptiles (5/11) and birds (4/7). These findings demonstrate the limited utility of universal primers for mini-barcoding, at least for these vertebrate taxa that we collected from the Saudi Arabian desert. 相似文献
997.
998.
Early marine migratory behaviour and apparent survival of hatchery-reared Seymour River steelhead (Oncorhynchus mykiss) smolts was examined over a four year period (2006-2009) to assess the impact of various management strategies on improving early marine survival. Acoustically tagged smolts were released to measure their survival using estuary and coastal marine receivers forming components of the Pacific Ocean Shelf Tracking (POST) array. Early marine survival was statistically indistinguishable between releases of summer run and winter run steelhead races, night and day releases, and groups released 10 days apart. In 2009, the survival of summer run steelhead released into the river was again trialed against groups released directly into the ocean at a distance from the river mouth. Apparent survival was improved significantly for the ocean released groups. The health and physiological status of the various release groups were monitored in years 2007-2009, and results indicate that the fish were in good health, with no clinical signs of disease at the time of release. The possibility of a disease event contributing to early marine mortality was further examined in 2009 by vaccinating half of the released fish against common fish diseases (vibriosis, furunculosis). The results suggest that marine survival may be enhanced using this approach, although not to the extent observed when the smolts were transported away from the river mouth before release. In summary, direct experimental testing of different release strategies using the POST array to measure ocean survival accelerated the scientific process by allowing rapid collection of data which enabled the rejection of several existing theories and allowed tentative identification of several new alternative approaches that might improve early marine survival of Seymour River steelhead. 相似文献
999.
Results from experimental studies of an electric discharge operating between a solid anode and an electrolytic cathode in
a wide pressure range are presented. Specific features of the discharge ignition and discharge shape and peculiarities the
structure of cathode spots on the electrolyte surface and anode spots on the surface of the solid electrode are revealed.
The dependences of the current density on the electrolytic cathode and metal anode on the total current are measured, and
the spatial distribution of the electric field is determined. A transition of a glow discharge into a multichannel discharge
is investigated. The experimental data on the frequency and amplitude of the current and voltage pulsations are presented.
Requirements for the maintenance of an electric discharge with an electrolytic cathode are formulated using the obtained experimental
results. 相似文献
1000.
Partinen M Saarenpää-Heikkilä O Ilveskoski I Hublin C Linna M Olsén P Nokelainen P Alén R Wallden T Espo M Rusanen H Olme J Sätilä H Arikka H Kaipainen P Julkunen I Kirjavainen T 《PloS one》2012,7(3):e33723