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排序方式: 共有1019条查询结果,搜索用时 15 毫秒
1.
Clelia Dallanoce Mara Canovi Carlo Matera Tiziana Mennini Marco De Amici Marco Gobbi Carlo De Micheli 《Bioorganic & medicinal chemistry》2012,20(21):6344-6355
A group of spirocyclic tropanyl-Δ2-isoxazolines was synthesized exploiting the 1,3-dipolar cycloaddition of nitrile oxides to olefins. Their interaction with the dopamine and serotonin transporters (DAT and SERT, respectively) was evaluated through binding experiments. The majority of the compounds had no inhibitory effects (IC50 >> 10 μM), while some had an IC50 value in the range 5–10 μM (8a–c, 10b and 11c on DAT, 12b on SERT). Unexpectedly, one of the tertiary amines under investigation, that is 3′-methoxy-8-methyl-spiro{8-azabicyclo[3.2.1]octane-3,5′(4′H)-isoxazole 7a, was able to enhance at a concentration of 10 μM both [3H]citalopram and [3H]paroxetine binding to SERT in rat brain homogenate (up to 25%, due to an increase of Bmax) and [3H]serotonin uptake (up to 30%) in cortical synaptosomes. This peculiar pharmacological profile of 7a suggests it binds to an allosteric site on SERT, and positions derivative 7a as a very useful tool to investigate SERT machinery. 相似文献
2.
Maria Francesca Mossuto Sara Sannino Davide Mazza Claudio Fagioli Milena Vitale Edgar Djaha Yoboue Roberto Sitia Tiziana Anelli 《PloS one》2014,9(10)
Precise coordination of protein biogenesis, traffic and homeostasis within the early secretory compartment (ESC) is key for cell physiology. As a consequence, disturbances in these processes underlie many genetic and chronic diseases. Dynamic imaging methods are needed to follow the fate of cargo proteins and their interactions with resident enzymes and folding assistants. Here we applied the Halotag labelling system to study the behavior of proteins with different fates and roles in ESC: a chaperone, an ERAD substrate and an aggregation-prone molecule. Exploiting the Halo property of binding covalently ligands labelled with different fluorochromes, we developed and performed non-radioactive pulse and chase assays to follow sequential waves of proteins in ESC, discriminating between young and old molecules at the single cell level. In this way, we could monitor secretion and degradation of ER proteins in living cells. We can also follow the biogenesis, growth, accumulation and movements of protein aggregates in the ESC. Our data show that protein deposits within ESC grow by sequential apposition of molecules up to a given size, after which novel seeds are detected. The possibility of using ligands with distinct optical and physical properties offers a novel possibility to dynamically follow the fate of proteins in the ESC. 相似文献
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Angel Valverde Araceli Burgos Tiziana Fiscella Raúl Rivas Encarna Velázquez Claudino Rodríguez-Barrueco Emilio Cervantes Manuel Chamber José-Mariano Igual 《Plant and Soil》2006,287(1-2):43-50
In the course of a project carried out in two regions of Spain, Castilla y León and Andalucía, aiming to find useful biofertilizers for staple grain-legumes, an efficient rhizobia nodulating chickpea (termed as C-2/2) and a powerful in vitro phosphate-solubilizing bacterial strain (termed as PS06) were isolated. Analyses of their 16S rDNA sequence indicated that they belong to the bacterial species Mesorhizobium ciceri and Pseudomonas jessenii, respectively. Greenhouse and field experiments were carried out in order to test the effect of single and dual inoculations on chickpea (ecotype ILC-482) growth. Under greenhouse conditions, plants inoculated with Mesorhizobium ciceri C-2/2 alone had the highest shoot dry weight. The inoculation treatment with P. jessenii PS06 yielded a shoot dry weight 14% greater than the uninoculated control treatment, but it was not correlated with shoot P contents. However, the co-inoculation of C-2/2 with PS06 resulted in a decrease in shoot dry weight with respect to the inoculation with C-2/2 alone. Under field conditions, plants inoculated with M. ciceri C-2/2, in single or dual inoculation, produced higher nodule fresh weight, nodule number and shoot N content than the other treatments. Inoculation with P. jessenii PS06 had no significant effect on plant growth. However, the co-inoculation treatment ranked the highest in seed yield (52% greater than the uninoculated control treatment) and nodule fresh weight. These data suggest that P. jessenii PS06 can act synergistically with M. ciceri C-2/2 in promoting chickpea growth. The contrasting results obtained between greenhouse and field experiments are discussed. 相似文献
6.
Equine and Canine Anaplasma phagocytophilum Strains Isolated on the Island of Sardinia (Italy) Are Phylogenetically Related to Pathogenic Strains from the United States 下载免费PDF全文
Alberto Alberti Rosanna Zobba Bernardo Chessa Maria Filippa Addis Olivier Sparagano Maria Luisa Pinna Parpaglia Tiziana Cubeddu Gianpaolo Pintori Marco Pittau 《Applied microbiology》2005,71(10):6418-6422
The presence of Anaplasma phagocytophilum, a tick-transmitted zoonotic pathogen, was investigated in Sardinia using a molecular approach. Phylogenetic analysis revealed that Sardinian strains are genetically distinct from the two lineages previously described in Europe and are closely related to strains isolated in different areas of the United States. 相似文献
7.
Lorena Rebecchi Roberto Guidetti Simona Borsari Tiziana Altiero Roberto Bertolani 《Hydrobiologia》2006,558(1):23-30
It is not rare to find in references that anhydrobiotic tardigrades can survive for more than a century. However, a closer
look at the empirical evidence provides very little support that tardigrades are capable of surviving dried for such a long
time. In order to resolve this discrepancy, we carried out a study to evaluate the long-term survival of naturally dried tardigrades.
A large fragment of dry lichen (Xanthoria parietina) was collected in the field two days after a rainy day in 1999. The dry lichen was stored inside a paper bag in the laboratory
at room temperature and humidity and under atmospheric oxygen exposure. Replicates of the dry lichen were re-hydrated after
various time periods of storage, with all tardigrades extracted and the survivors enumerated. Five species of tardigrades
were found, but two of them only occasionally. Ramazzottius oberhaeuseri, Echiniscus testudo and Echiniscus trisetosus were sufficiently represented for statistical analysis. At the beginning of the experiment 91.1% of R. oberhaeuseri and 71.7% of Echiniscus spp. were alive. R. oberhaeuseri survived up to 1604 days, while Echiniscus spp. lived up to 1085 days. Recovery after four years of anhydrobiosis has to be considered a very good long-term survival,
which is important from an ecological and evolutionary point of view. 相似文献
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9.
Godwin Nana Yaw Lemgo Silvia Sabbadini Tiziana Pandolfini Bruno Mezzetti 《Transgenic research》2013,22(6):1073-1088
A major application of RNA interference (RNAi) is envisaged for the production of virus-resistant transgenic plants. For fruit trees, this remains the most, if not the only, viable option for the control of plant viral disease outbreaks in cultivated orchards, due to the difficulties associated with the use of traditional and conventional disease-control measures. The use of RNAi might provide an additional benefit for woody crops if silenced rootstock can efficiently transmit the silencing signal to non-transformed scions, as has already been demonstrated in herbaceous plants. This would provide a great opportunity to produce non-transgenic fruit from transgenic rootstock. In this review, we scrutinise some of the concerns that might arise with the use of RNAi for engineering virus-resistant plants, and we speculate that this virus resistance has fewer biosafety concerns. This is mainly because RNAi-eliciting constructs only express small RNA molecules rather than proteins, and because this technology can be applied using plant rootstock that can confer virus resistance to the scion, leaving the scion untransformed. We discuss the main biosafety concerns related to the release of new types of virus-resistant plants and the risk assessment approaches in the application of existing regulatory systems (in particular, those of the European Union, the USA, and Canada) for the evaluation and approval of RNAi-mediated virus-resistant plants, either as transgenic varieties or as plant virus resistance induced by transgenic rootstock. 相似文献
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