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141.
Stelios Eleftheratos Philip Spearpoint Gabriella Ortore Antonios Kolocouris Adriano Martinelli Stephen Martin Alan Hay 《Bioorganic & medicinal chemistry letters》2010,20(14):4182-4187
Interaction of aminoadamantanes with the influenza A virus M2 proton channel was analyzed by docking simulations of a series of synthetic aminoadamantane derivatives, of differing binding affinity, into the crystal structure of the transmembrane (M2TM) pore. The pore blocking model tested in the ‘gas phase’ describes qualitatively the changes on the relative binding affinities of the compounds (although a series of highly hydrophobic ligands which seem to have little capacity for different specific interactions with their receptor). The docking calculations predicted poses in which the adamantane ring is surrounded mainly by the alkyl side chains of Val27 or Ala30 and the ligand’s amino group is generally hydrogen bonded with hydroxyls of Ser31 or carbonyls of Val27 or carbonyls of Ala30, the former (Ser31) being the most stable and most frequently observed. The binding of the ligand is a compromise between hydrogen bonding ability, which is elevated by a primary amino group, and apolar interactions, which are increased by the ability of the lipophilic moiety to adequately fill a hydrophobic pocket within the M2TM pore. A delicate balance of these hydrophobic contributions is required for optimal interaction. 相似文献
142.
Luis G. García-Montero Paloma Díaz Gabriella Di Massimo Antonio García-Abril 《Mycological Progress》2010,9(3):315-335
Truffles are abundant in some regions of China. Nevertheless, it was not until the 1980s that Tuber species were discovered by Chinese mycologists. In recent years, international truffle markets have shown an increasing interest
in the import of Chinese Tuber. These truffles serve as a complement to European truffles due to their lower prices and their greater availability in a
deficit market. However, Chinese truffles have been the subject of fraudulent commercial practices, and these could have a
negative effect on truffle culture. These concerns have been behind numerous recent studies designed to obtain detailed information
about Chinese Tuber species. Unfortunately, many of these studies are not published in English, and are dispersed throughout the specific local
or national bibliography and proceedings of specialized truffle conferences. In view of the need to expand current knowledge
of Chinese Tuber species, we present a comprehensive summary of the taxonomy, ecology, mycorrhizae, genetics, biochemistry, and cultivation
of Chinese Tuber species. We also provide a synthetic taxonomy and morphological characterization of 16 Chinese Tuber species in order to assist in their verification and monitoring. 相似文献
143.
Edit Kaszab Balázs Kriszt Béla Atzél Gabriella Szabó István Szabó Péter Harkai Sándor Szoboszlay 《Microbial ecology》2010,59(1):37-45
The main aim of this paper was the comprehensive estimation of the occurrence rate and the antibiotic-resistance conditions
of opportunistic pathogen Pseudomonas aeruginosa in hydrocarbon-contaminated environments. From 2002 to 2007, 26 hydrocarbon-contaminated sites of Hungary were screened for
the detection of environmental isolates. Altogether, 156 samples were collected and examined for the determination of appearance, representative cell counts, and
antibiotic-resistance features of P. aeruginosa. The detected levels of minimal inhibitory concentrations of ten different drugs against 36 environmental strains were compared
to the results of a widely used reference strain ATCC 27853 and four other clinical isolates of P. aeruginosa. Based on our long-term experiment, it can be established that species P. aeruginosa was detectable in case of 61.5% of the investigated hydrocarbon-contaminated sites and 35.2% of the examined samples that
shows its widespread occurrence in polluted soil–groundwater systems. In the course of the antibiotic-resistance assay, our
results determined that 11 of the examined 36 environmental strains had multiple drug-resistance against several clinically
effective antimicrobial classes: cephalosporins, wide spectrum penicillins, carbapenems, fluoroquinolones, and aminoglycosides.
The fact that these multiresistant strains were isolated from 8 different hydrocarbon-contaminated sites, mainly from outskirts,
confirms that multiple drug-resistance of P. aeruginosa is widespread not only in clinical, but also in natural surroundings as well. 相似文献
144.
Gabriella Tamasi Agnese Magnani Luisa Chiasserini Chiara Gabbiani Michael A. Jakupec Michael B. Hursthouse 《Journal of inorganic biochemistry》2010,104(8):799-313
The reaction of aqueous cis-[Pt(NH3)2(H2O)2](NO3)2 with Na+HMEL− (H2MEL, meloxicam, 4-hydroxy-2-methyl-N-(5-methyl-1,3-thiazol-2-yl)-2H-1,2-benzothiazine-3-carboxamide-1,1-dioxide), and Na+HISO− (H2ISO, isoxicam, 4-hydroxy-2-methyl-N-(5-methylisoxazol-3-yl)-2H-1,2-benzothiazine-3-carboxamide-1,1-dioxide) at pH 7 produced micro-crystalline cis-[Pt(NH3)2(N1′-HMEL)2], 5 and cis-[Pt(NH3)2(N1′-HISO)2], 6. The X-ray diffraction structure of 5 shows two HMEL− anions donating through the thiazole nitrogen atoms and adopting a head-to-tail (HT) conformation. The 1H NMR spectrum for 5 from DMSO-d6 shows inertness of the complex up to at least 24 h. Delivery studies for 5 and 6 from vinyl hydrogel based on l-phenylalanine (pH 6.5, 25 °C) show that concentrations of complexes ranging between 2.5 and 5 μM can be reached after a day. Compounds 5 and 6 show strong anti-proliferative effects on CH1 cells (ovarian carcinoma, human) in vitro, IC50 values being 0.60 and 0.37 μM, respectively (0.16 μM for reference, cis-diamminodichloridoplatinum(II), cisplatin). ESI-MS measurements clearly documented that both 5 and 6 form adducts with the three model proteins ubiquitin (UBI), cytochrome c (CYT C) and superoxide dismutase (SOD), the HISO− complex being significantly more effective than the HMEL− one. Density functional methods help in finding rationale for the easiest dissociation of Pt-H2ISO/HISO bonds when compared to the Pt-N1′-H2MEL/N1′-HMEL linkages. 相似文献
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Vilmos Soós Endre Sebestyén Angéla Juhász Marnie E Light Ladislav Kohout Gabriella Szalai Júlia Tandori Johannes Van Staden Ervin Balázs 《BMC plant biology》2010,10(1):236
Background
Smoke released from burning vegetation functions as an important environmental signal promoting the germination of many plant species following a fire. It not only promotes the germination of species from fire-prone habitats, but several species from non-fire-prone areas also respond, including some crops. The germination stimulatory activity can largely be attributed to the presence of a highly active butenolide compound, 3-methyl-2H-furo[2,3-c]pyran-2-one (referred to as karrikin 1 or KAR1), that has previously been isolated from plant-derived smoke. Several hypotheses have arisen regarding the molecular background of smoke and KAR1 action. 相似文献149.
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