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131.
Göknur Kalkan Nevin Karakus Yalçın Baş Zennure Takçı Pınar Özuğuz Ömer Ateş Serbulent Yigit 《Gene》2013
Objective
Alopecia areata (AA) is hypothesized to be an organ-specific autoimmune disease of hair follicles mediated by T cells. As immunological and genetic factors have been implicated in the pathogenesis of AA, the purpose of the present study was to investigate possible associations between the functional Interleukin (IL)-4 gene intron 3 VNTR polymorphism and AA susceptibility and disease progression in Turkish population.Methods
The study group consisted of 116 unrelated patients with AA and 125 unrelated healthy controls. Genomic DNA was isolated and IL-4 gene 70 bp VNTR polymorphism determined by using polymerase chain reaction (PCR) with specific primers.Results
No association was observed between AA patients and controls according to genotype distribution (p = 0.051). The allele distribution of IL-4 gene intron 3 VNTR polymorphism was statistically different between AA patients and control group (p = 0.026). The frequency of P1 allele in patients was significantly higher than that in the control group. When the P2P2 genotype was compared with P1P2 + P1P1 genotypes, a statistically significant difference was observed between patients and controls (p = 0.036). Intron 3 VNTR polymorphism in the IL-4 gene was found to be associated with AA susceptibility in Turkish population.Conclusion
The results suggest that IL-4 VNTR polymorphism in the intron 3 region may be a risk factor for the development of AA among Turkish population. This is the first to report that intron 3 VNTR polymorphism in the IL-4 gene is associated with AA susceptibility. 相似文献132.
Sleep and Biological Rhythms - Sleep duration and quality are associated with many diseases. Evaluating the relationship between nutrient intake and sleep quality is important, because dietary... 相似文献
133.
Centaurea tchihatcheffii is a steppic annual possessing some unique features absent in other Centaureas. The chromosome number is 2n = 20, differing
from all other annual species of Centaurea sect. Cyanus. The type locality as published is erroneous and the correct provenance is provided. 相似文献
134.
Lack of Electricity Production by Pelobacter carbinolicus Indicates that the Capacity for Fe(III) Oxide Reduction Does Not Necessarily Confer Electron Transfer Ability to Fuel Cell Anodes
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Hanno Richter Martin Lanthier Kelly P. Nevin Derek R. Lovley 《Applied microbiology》2007,73(16):5347-5353
The ability of Pelobacter carbinolicus to oxidize electron donors with electron transfer to the anodes of microbial fuel cells was evaluated because microorganisms closely related to Pelobacter species are generally abundant on the anodes of microbial fuel cells harvesting electricity from aquatic sediments. P. carbinolicus could not produce current in a microbial fuel cell with electron donors which support Fe(III) oxide reduction by this organism. Current was produced using a coculture of P. carbinolicus and Geobacter sulfurreducens with ethanol as the fuel. Ethanol consumption was associated with the transitory accumulation of acetate and hydrogen. G. sulfurreducens alone could not metabolize ethanol, suggesting that P. carbinolicus grew in the fuel cell by converting ethanol to hydrogen and acetate, which G. sulfurreducens oxidized with electron transfer to the anode. Up to 83% of the electrons available in ethanol were recovered as electricity and in the metabolic intermediate acetate. Hydrogen consumption by G. sulfurreducens was important for ethanol metabolism by P. carbinolicus. Confocal microscopy and analysis of 16S rRNA genes revealed that half of the cells growing on the anode surface were P. carbinolicus, but there was a nearly equal number of planktonic cells of P. carbinolicus. In contrast, G. sulfurreducens was primarily attached to the anode. P. carbinolicus represents the first Fe(III) oxide-reducing microorganism found to be unable to produce current in a microbial fuel cell, providing the first suggestion that the mechanisms for extracellular electron transfer to Fe(III) oxides and fuel cell anodes may be different. 相似文献
135.
Holly R. Yeatman J. Robert Lane Kwok Ho Christopher Choy Nevin A. Lambert Patrick M. Sexton Arthur Christopoulos Meritxell Canals 《The Journal of biological chemistry》2014,289(22):15856-15866
Allosteric modulators are an attractive approach to achieve receptor subtype-selective targeting of G protein-coupled receptors. Benzyl quinolone carboxylic acid (BQCA) is an unprecedented example of a highly selective positive allosteric modulator of the M1 muscarinic acetylcholine receptor (mAChR). However, despite favorable pharmacological characteristics of BQCA in vitro and in vivo, there is limited evidence of the impact of allosteric modulation on receptor regulatory mechanisms such as β-arrestin recruitment or receptor internalization and endocytic trafficking. In the present study we investigated the impact of BQCA on M1 mAChR regulation. We show that BQCA potentiates agonist-induced β-arrestin recruitment to M1 mAChRs. Using a bioluminescence resonance energy transfer approach to monitor intracellular trafficking of M1 mAChRs, we show that once internalized, M1 mAChRs traffic to early endosomes, recycling endosomes and late endosomes. We also show that BQCA potentiates agonist-induced subcellular trafficking. M1 mAChR internalization is both β-arrestin and G protein-dependent, with the third intracellular loop playing an important role in the dynamics of β-arrestin recruitment. As the global effect of receptor activation ultimately depends on the levels of receptor expression at the cell surface, these results illustrate the need to extend the characterization of novel allosteric modulators of G protein-coupled receptors to encapsulate the consequences of chronic exposure to this family of ligands. 相似文献
136.
Amelia-Elena Rotaru Pravin Malla Shrestha Fanghua Liu Beatrice Markovaite Shanshan Chen Kelly P. Nevin Derek R. Lovley 《Applied and environmental microbiology》2014,80(15):4599-4605
Direct interspecies electron transfer (DIET) is potentially an effective form of syntrophy in methanogenic communities, but little is known about the diversity of methanogens capable of DIET. The ability of Methanosarcina barkeri to participate in DIET was evaluated in coculture with Geobacter metallireducens. Cocultures formed aggregates that shared electrons via DIET during the stoichiometric conversion of ethanol to methane. Cocultures could not be initiated with a pilin-deficient G. metallireducens strain, suggesting that long-range electron transfer along pili was important for DIET. Amendments of granular activated carbon permitted the pilin-deficient G. metallireducens isolates to share electrons with M. barkeri, demonstrating that this conductive material could substitute for pili in promoting DIET. When M. barkeri was grown in coculture with the H2-producing Pelobacter carbinolicus, incapable of DIET, M. barkeri utilized H2 as an electron donor but metabolized little of the acetate that P. carbinolicus produced. This suggested that H2, but not electrons derived from DIET, inhibited acetate metabolism. P. carbinolicus-M. barkeri cocultures did not aggregate, demonstrating that, unlike DIET, close physical contact was not necessary for interspecies H2 transfer. M. barkeri is the second methanogen found to accept electrons via DIET and the first methanogen known to be capable of using either H2 or electrons derived from DIET for CO2 reduction. Furthermore, M. barkeri is genetically tractable, making it a model organism for elucidating mechanisms by which methanogens make biological electrical connections with other cells. 相似文献
137.
Twenty-first century life sciences have transformed into data-enabled (also called data-intensive, data-driven, or big data) sciences. They principally depend on data-, computation-, and instrumentation-intensive approaches to seek comprehensive understanding of complex biological processes and systems (e.g., ecosystems, complex diseases, environmental, and health challenges). Federal agencies including the National Science Foundation (NSF) have played and continue to play an exceptional leadership role by innovatively addressing the challenges of data-enabled life sciences. Yet even more is required not only to keep up with the current developments, but also to pro-actively enable future research needs. Straightforward access to data, computing, and analysis resources will enable true democratization of research competitions; thus investigators will compete based on the merits and broader impact of their ideas and approaches rather than on the scale of their institutional resources. This is the Final Report for Data-Intensive Science Workshops DISW1 and DISW2. The first NSF-funded Data Intensive Science Workshop (DISW1, Seattle, WA, September 19-20, 2010) overviewed the status of the data-enabled life sciences and identified their challenges and opportunities. This served as a baseline for the second NSF-funded DIS workshop (DISW2, Washington, DC, May 16-17, 2011). Based on the findings of DISW2 the following overarching recommendation to the NSF was proposed: establish a community alliance to be the voice and framework of the data-enabled life sciences. After this Final Report was finished, Data-Enabled Life Sciences Alliance (DELSA, www.delsall.org ) was formed to become a Digital Commons for the life sciences community. 相似文献
138.
Nevin JA 《Behavioural processes》2012,90(1):84-6; discussion 87-8
In this article, Gallistel proposes information theory as an approach to some enduring problems in the study of operant and classical conditioning. 相似文献
139.
140.
The alpha-conotoxin RgIA is a selective antagonist of the alpha9alpha10 nicotinic acetylcholine receptor and has been shown to be a potent analgesic and reduces nerve injury associated inflammation. RgIA was chemically synthesized and found to fold into two disulfide isomers, globular and ribbon. The native globular isomer inhibited ACh-evoked currents reversibly in oocytes expressing rat alpha9alpha10 nAChRs but the ribbon isomer was inactive. We determined the three-dimensional structure of RgIA using NMR methods to assist in elucidating the molecular role of RgIA in analgesia and inflammation. 相似文献