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971.
Andreas Vécsei Andrea Kipet Albina Innerhofer Ulrike Graf Christa Binder Heidemarie Gizci Karin Hammer Andrea Bruckdorfer Wolf‐Dietrich Huber Alexander M. Hirschl Athanasios Makristathis 《Helicobacter》2010,15(3):214-220
Background: Increase of antibiotic resistance is a worldwide problem. Within the 4 years before the turn of the millennium Helicobacter pylori strains isolated in children living in Vienna, Austria, showed a primary clarithromycin and metronidazole resistance of 20% and 16%, respectively. The aim of this retrospective follow‐up survey was to assess the further development and current antimicrobial resistance status. Methods: Children having undergone upper endoscopy between March 2002 and March 2008 at the same two co‐operating pediatric gastroenterology units which had also been collaborating on the prior assessment were included. H. pylori infection was diagnosed by rapid urease test, histology, and culture. If the latter was positive, susceptibility testing to amoxicillin, clarithromycin and metronidazole by E‐test followed. From March 2004 onwards, susceptibility to levofloxacin, tetracycline and rifampin was additionally assessed. Results: Out of 897 children, 153 had a proven infection with H. pylori and no history of prior eradication treatment. Their median age was 11.5 years (range 0.5–20.9 years). Primary resistance to clarithromycin and metronidazole were 34% and 22.9%, respectively; dual resistance was found in 9.8% of the strains; 0.9% was resistant to tetracycline and rifampin, respectively. No case of amoxicillin resistance was detected. The only independent risk factor for clarithromycin resistance turned out to be the origin of a child from Austrian parents. Conclusions: In the last decade, the rate of primary resistance of H. pylori to clarithromycin continued to rise. No significant change was found regarding primary resistance to metronidazole or dual resistance to metronidazole and clarithromycin, respectively. 相似文献
972.
Chiral α‐methylbenzyl amine is a well known and often used chiral auxiliary, e.g., in the resolution of racemates or asymmetric catalysis. In this work, α‐methylbenzyl amine and its derivatives N,α‐dimethylbenzyl amine, N,N,α‐trimethylbenzyl amine, and bis[α‐methylbenzyl] amine were investigated by vibrational circular dichroism (VCD) spectroscopy and density functional theory (DFT). For all compounds, stable low energy conformers were obtained by the DFT calculations and based on those, the theoretical vibrational absorption (VA) and VCD spectra were calculated and compared with experimental spectra. Hence, the absolute configurations and conformational preferences were determined. A qualitative comparison of all the experimental VCD spectra of the investigated chiral molecules supported by the calculated ones is given which clearly shows similarities between the spectra of the different chiral amines. These can be assigned to vibrations of the unchanged chiral center. Chirality 2010. © 2010 Wiley‐Liss, Inc. 相似文献
973.
Thomas M. Koutsos Georgios C. Dimopoulos Andreas P. Mamolos 《Ecological Engineering》2010,36(8):1017-1027
The main purpose of this study was the development of an impact evaluation model to effectively assess and map possible ecological impacts due to a dam construction on habitats and species from the nearest Natura 2000 sites. A new approach has been developed in order to assess and map possible impacts on habitats due to a dam construction at both construction and operation phase. This methodology includes procedures in order to assess impacts and by calculating evaluation scores. Using Geographical Information Systems (GIS) evaluation scores were assigned to grouped habitat regions at construction and operation dam phase. The construction may affect the presence of the species Lutra at the site near the river but will have no effect at the area where the dam basin and the Natura 2000 site intersect. The other species are not expected to be affected from the dam construction. During the operation phase, the presence of water will influence species like Bombina in a very positive way. The dam operation itself will not have negative effects on the rest of habitats but due to the presence of water, factors like a possible increase on traffic and population may affect negatively the habitats especially near the village areas. The proposed methodology offers an alternative point of view on impact assessment and it is expected to serve as become a valuable tool for decision makers to evaluate potential impacts to threatened species and habitats due to a technical project at construction and operation phase. 相似文献
974.
Andreas Jørgensen Lufanna C. H. Lai Michael Z. Hauschild 《The International Journal of Life Cycle Assessment》2010,15(1):5-16
Background, aim and scope
Assuming that the goal of social life cycle assessment (SLCA) is to assess damage and benefits on its ‘area of protection’ (AoP) as accurately as possible, it follows that the impact pathways, describing the cause effect relationship between indicator and the AoP, should have a consistent theoretical foundation so the inventory results can be associated with a predictable damage or benefit to the AoP. This article uses two concrete examples from the work on SLCA to analyse to what extent this is the case in current practice. One considers whether indicators included in SLCA approaches can validly assess impacts on the well-being of the stakeholder, whereas the other example addresses whether the ‘incidence of child labour’ is a valid measure for impacts on the AoPs. 相似文献975.
976.
Francisca Reyes Gabriel León Maribel Donoso Federica Brandizzí Andreas P.M. Weber Ariel Orellana 《The Plant journal : for cell and molecular biology》2010,61(3):423-435
Uridine 5′‐diphosphate (UDP)‐glucose is transported into the lumen of the endoplasmic reticulum (ER), and the Arabidopsis nucleotide sugar transporter AtUTr1 has been proposed to play a role in this process; however, different lines of evidence suggest that another transporter(s) may also be involved. Here we show that AtUTr3 is involved in the transport of UDP‐glucose and is located at the ER but also at the Golgi. Insertional mutants in AtUTr3 showed no obvious phenotype. Biochemical analysis in both AtUTr1 and AtUTr3 mutants indicates that uptake of UDP‐glucose into the ER is mostly driven by these two transporters. Interestingly, the expression of AtUTr3 is induced by stimuli that trigger the unfolded protein response (UPR), a phenomenon also observed for AtUTr1, suggesting that both AtUTr1 and AtUTr3 are involved in supplying UDP‐glucose into the ER lumen when misfolded proteins are accumulated. Disruption of both AtUTr1 and AtUTr3 causes lethality. Genetic analysis showed that the atutr1 atutr3 combination was not transmitted by pollen and was poorly transmitted by the ovules. Cell biology analysis indicates that knocking out both genes leads to abnormalities in both male and female germ line development. These results show that the nucleotide sugar transporters AtUTr1 and AtUTr3 are required for the incorporation of UDP‐glucose into the ER, are essential for pollen development and are needed for embryo sac progress in Arabidopsis thaliana. 相似文献
977.
Eva Stauffer Alexander Westermann Gabriele Wagner Andreas Wachter 《The Plant journal : for cell and molecular biology》2010,64(2):243-255
Alternative splicing (AS) of precursor mRNAs is a widespread phenomenon in plants; however, many questions, especially regarding its regulation and functional implications, remain to be elucidated. In vertebrates, polypyrimidine tract‐binding proteins (PTBs) have been identified as key splicing factors influencing splice site selection and orchestrating coordinated splicing programmes during developmental processes. Here, we analysed three PTB homologues from Arabidopsis thaliana and provide evidence for their gene regulatory potential based on AS and a splicing‐independent mechanism. Our data reveal that Arabidopsis PTB homologues are subject to extensive auto‐ and cross‐regulation via AS‐coupled nonsense‐mediated decay, thereby establishing a basis for interlinking their expression. Furthermore, the multiple modes of action of Arabidopsis PTB homologues are reflected in their subcellular localization in the nucleus, cytosol and processing bodies. This work provides insight into the regulation of AS in plants and highlights the regulatory potential of the multifunctional plant PTB homologues, which might have important implications in diverse biological processes. 相似文献
978.
979.
Hanessian S Larsson A Fex T Knecht W Blomberg N 《Bioorganic & medicinal chemistry letters》2010,20(23):6925-6928
The synthesis of a series of novel macrocyclic compounds designed to target blood coagulation Factor XIa is described. The compounds were evaluated for their inhibition of a small set of serine proteases. Several compounds displayed modest activity and good selectivity for Factor XIa. Within the series, a promising lead structure for developing novel macrocyclic inhibitors of thrombin was identified. 相似文献
980.
André Alker Alfred Binggeli Andreas D. Christ Luke Green Hans Peter Maerki Rainer E. Martin Peter Mohr 《Bioorganic & medicinal chemistry letters》2010,20(15):4521-4525
Nicotinamides of benzyl-substituted 4-aminopiperidines and their seven-membered analogs of generic structure 2 and 2′ have been discovered as potent and selective SST5 antagonists. The activity (Ki) ranges from 2.4 to 436 nM. Most compounds exhibit decent physicochemical properties and follow a clear SAR pattern. Interestingly enough, the receptor is strongly enantiodiscriminating and binds in the amino-azepane-series only the (R)-enantiomer. 相似文献