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81.
Bettendorff L Wirtzfeld B Makarchikov AF Mazzucchelli G Frédérich M Gigliobianco T Gangolf M De Pauw E Angenot L Wins P 《Nature chemical biology》2007,3(4):211-212
Several important cofactors are adenine nucleotides with a vitamin as the catalytic moiety. Here, we report the discovery of the first adenine nucleotide containing vitamin B1: adenosine thiamine triphosphate (AThTP, 1), or thiaminylated ATP. We discovered AThTP in Escherichia coli and found that it accumulates specifically in response to carbon starvation, thereby acting as a signal rather than a cofactor. We detected smaller amounts in yeast and in plant and animal tissues. 相似文献
82.
Gobbi M Funicello M Gerstbrein K Holy M Moya PR Sotomayor R Forray MI Gysling K Paluzzi S Bonanno G Reyes-Parada M Sitte HH Mennini T 《Journal of neurochemistry》2008,105(5):1770-1780
We studied two non-neurotoxic amphetamine derivatives (methyl-thioamphetamine, MTA and N,N- dimethylMTA, DMMTA) interacting with serotonin (5-HT) transporters (SERTs) with affinities comparable to that of p- Cl-amphetamine (pCA). The rank order for their maximal effects in inducing both [3 H]5-HT release from rat brain synaptosomes or hSERT-expressing HEK-293 cells, and currents in hSERT-expressing oocytes, was pCA >> MTA ≥ DMMTA. A correlation between drug-induced release and currents is also strengthened by the similar bell shape of the dose–response curves. Release experiments indicated that MTA and DMMTA are SERT substrates although MTA is taken up by HEK-293 cells with a V max 40% lower than pCA. The weak effects of MTA and DMMTA in vitro might therefore be due to their properties as 'partial substrates' on the mechanisms, other than translocation, responsible for currents and/or release. After either local or systemic in vivo administration, MTA and DMMTA release 5-HT in a manner comparable to pCA. These findings confirm that the neurotoxic properties of some amphetamine derivatives are independent of their 5-HT-releasing activity in vivo . It is worth noting that only those amphetamine derivatives with high efficiency in inducing 5-HT release and currents in vitro have neurotoxic properties. 相似文献
83.
Fadhlaoui-Zid Karima Cossu Piero Sanna Daria Scarpa Fabio Lai Tiziana Castelli Alberto Casu Marco Maltagliati Ferruccio 《Hydrobiologia》2021,848(18):4225-4240
Hydrobiologia - Recent research hypothesised that the Siculo-Tunisian Strait might fit, at least for some species, the picture of a genetic transitional zone instead of a sharp genetic break... 相似文献
84.
85.
Porro D Gasser B Fossati T Maurer M Branduardi P Sauer M Mattanovich D 《Applied microbiology and biotechnology》2011,89(4):939-948
Recombinant DNA (rDNA) technologies allow the production of a wide range of peptides, proteins and metabolites from naturally
non-producing cells. Since human insulin was the first heterologous compound produced in a laboratory in 1977, rDNA technology
has become one of the most important technologies developed in the 20th century. Recombinant protein and metabolites production
is a multi-billion dollar market. The development of a new product begins with the choice of the cell factory. The final application
of the compound dictates the main criteria that should be taken into consideration: (1) quality, (2) quantity, (3) yield and
(4) space time yield of the desired product. Quantity and quality are the most predominant requirements that must be considered
for the commercial production of a protein. Quantity and yield are the requirements for the production of a metabolite. Finally,
space time yield is crucial for any production process. It therefore becomes clear why the perfect host does not exist yet,
and why—despite important advances in rDNA applications in higher eukaryotic cells—microbial biodiversity continues to represent
a potential source of attractive cell factories. In this review, we compare the advantages and limitations of the principal
yeast and bacterial workhorse systems. 相似文献
86.
Alessandra Dalmasso Tiziana Civera Virginia Filipello Maria Teresa Bottero 《Molecular biology reports》2014,41(10):6329-6333
A multiplex primer-extension reaction (PER) assay, was specifically designed for the identification of ten Yersinia species. The assay, directed towards the tufA (elongation factor Tu) gene, was tested on a total of 42 samples representing Yersinia species and non-Yersinia species. The primers used in the preliminary PCR, designed in highly conserved regions upstream and downstream of the diagnosis sites, successfully amplified a 587 bp fragment. The diagnosis sites were simultaneously interrogated using a multiplex PER and the results were confirmed by fragment sequencing. The proposed test provides an appropriate tool to monitor the presence of Yersinia spp. in food samples and to evaluate the potential hazard for consumers. 相似文献
87.
RNA silencing controls endogenous gene expression and drives defensive reactions against invasive nucleic acids like viruses. In plants, it has been demonstrated that RNA silencing can be transmitted through grafting between scions and silenced rootstocks to attenuate virus and viroid accumulation in the scions. This has been obtained mostly using transgenic plants, which may be a drawback in current agriculture. In the present study, we examined the dynamics of infection of a resistance-breaking strain of Tomato spotted wilt virus (RB-TSWV) through the graft between an old Apulian (southern Italy) tomato variety, denoted Sl-Ma, used as a rootstock and commercial tomato varieties used as scions. In tests with non-grafted plants, Sl-Ma showed resistance to the RB-TSWV infection as viral RNA accumulated at low levels and plants recovered from disease symptoms by 21 days post inoculation. The resistance trait was transmitted to the otherwise highly susceptible tomato genotypes grafted onto Sl-Ma. The results from the analysis of small RNAs hallmark genes involved in RNA silencing and virus-induced gene silencing suggest that RNA silencing is involved in the resistance showed by Sl-Ma against RB-TSWV and in scions grafted on this rootstock. The results from self-grafted susceptible tomato varieties suggest also that RNA silencing is enhanced by the graft itself. We can foresee interesting practical implications of the approach described in this paper. 相似文献
88.
Bruzzone S Basile G Mannino E Sturla L Magnone M Grozio A Salis A Fresia C Vigliarolo T Guida L De Flora A Tossi V Cassia R Lamattina L Zocchi E 《Journal of cellular physiology》2012,227(6):2502-2510
UV-B is an abiotic environmental stress in both plants and animals. Abscisic acid (ABA) is a phytohormone regulating fundamental physiological functions in plants, including response to abiotic stress. We previously demonstrated that ABA is an endogenous stress hormone also in animal cells. Here, we investigated whether autocrine ABA regulates the response to UV-B of human granulocytes and keratinocytes, the cells involved in UV-triggered skin inflammation. The intracellular ABA concentration increased in UV-B-exposed granulocytes and keratinocytes and ABA was released into the supernatant. The UV-B-induced production of NO and of reactive oxygen species (ROS), phagocytosis, and cell migration were strongly inhibited in granulocytes irradiated in the presence of a monoclonal antibody against ABA. Moreover, presence of the same antibody strongly inhibited release of NO, prostaglandin E2 (PGE(2)), and tumor necrosis factor-α (TNF-α) by UV-B irradiated keratinocytes. Lanthionine synthetase C-like protein 2 (LANCL2) is required for the activation of the ABA signaling pathway in human granulocytes. Silencing of LANCL2 in human keratinocytes by siRNA was accompanied by abrogation of the UV-B-triggered release of PGE(2), TNF-α, and NO and ROS production. These results indicate that UV-B irradiation induces ABA release from human granulocytes and keratinocytes and that autocrine ABA stimulates cell functions involved in skin inflammation. 相似文献
89.
Skidmore J Atcha Z Boucherat E Castelletti L Chen DW Coppo FT Cutler L Dunsdon RM Heath BM Hutchings R Hurst DN Javed S Martin S Maskell ES Norton D Pemberton DJ Redshaw S Rutter R Sehmi SS Scoccitti T Temple HE Theobald P Ward RW Wilson DM 《Bioorganic & medicinal chemistry letters》2012,22(10):3560-3563
A series of α7 nicotinic acetylcholine receptor full-agonists with a 1,3,4-oxadiazol-2-amine core has been discovered. Systematic exploration of the structure-activity relationships for both α7 potency and selectivity with respect to interaction with the hERG channel are described. Further profiling led to the identification of compound 22, a potent full agonist showing efficacy in the novel object recognition model of cognition enhancement. 相似文献