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971.
The oxidative phosphorylation (OXPHOS) is the primary energy-producing process of all aerobic organisms and the only cellular function under the dual control of both the mitochondrial and the nuclear genomes. Functional characterization and evolutionary study of the OXPHOS system is of great importance for the understanding of many as yet unclear aspects of nucleus-mitochondrion genomic co-evolution and co-regulation gene networks. The MitoDrome database is a web-based database which provides genomic annotations about nuclear genes of Drosophila melanogaster encoding for mitochondrial proteins. Recently, MitoDrome has included a new section annotating genomic information about OXPHOS genes in Drosophila pseudoobscura and Anopheles gambiae and their comparative analysis with their Drosophila melanogaster and human counterparts. The introduction of this new comparative annotation section into MitoDrome is expected to be a useful resource for both functional and structural genomics related to the OXPHOS system.  相似文献   
972.
Proteomic screening of strawberry (Fragaria ananassa) yielded a 58% success rate in protein identification in spite of the fact that no genomic sequence is available for this species. This was achieved by a combination of MALDI-MS/MS de novo sequencing of double-derivatized peptides and indel-tolerant searching against local protein databases built on both EST and full-length nucleotide sequences. The amino acid sequence of a strawberry allergen, homologous to the well-known major birch pollen allergen Bet v 1, was partially determined. This strawberry allergen, named Fra a 1 according to the nomenclature for allergen proteins, showed sequence identity of 54 and 77%, respectively, with corresponding allergens from birch and apple. Differential expression, as evaluated by 2-D DIGE, occurred in 10% of protein spots when red strawberries were compared to a colorless (white) strawberry mutant. White strawberries, known to be tolerated by individuals affected by allergy, were found to be virtually free from the strawberry allergen. Also several enzymes in the pathway for biosynthesis of flavonoids, to which the red color pelargonidin belongs, were down-regulated. This approach to assess differential protein expression without access to genomic sequence information can also be applied to other crop plants and phenotypic traits.  相似文献   
973.
974.
This study investigated traditional cement-based and non-conventional (using accelerated carbonation) solidification/stabilization to treat 2 dredged sediments contaminated with mercury from two different locations in UK. Canal and estuarine-derived sediments were mixed with blended binders and powdered activated carbon. Fresh mixtures of sediment and cement were exposed to gaseous carbon dioxide and were allowed to carbonate for fixed time periods, after which they were cured for 28 days. Following curing, samples were leach tested to evaluate the fixation of mercury in the treated products. The results obtained indicated that both conventional and accelerated carbonated treatments were capable of reducing the concentration of mercury in the eluates to acceptable limits.  相似文献   
975.
976.
Necroptosis is a highly pro-inflammatory mode of cell death regulated by RIP (or RIPK)1 and RIP3 kinases and mediated by the effector MLKL. We report that diverse bacterial pathogens that produce a pore-forming toxin (PFT) induce necroptosis of macrophages and this can be blocked for protection against Serratia marcescens hemorrhagic pneumonia. Following challenge with S. marcescens, Staphylococcus aureus, Streptococcus pneumoniae, Listeria monocytogenes, uropathogenic Escherichia coli (UPEC), and purified recombinant pneumolysin, macrophages pretreated with inhibitors of RIP1, RIP3, and MLKL were protected against death. Alveolar macrophages in MLKL KO mice were also protected during S. marcescens pneumonia. Inhibition of caspases had no impact on macrophage death and caspase-1 and -3/7 were determined to be inactive following challenge despite the detection of IL-1β in supernatants. Bone marrow-derived macrophages from RIP3 KO, but not caspase-1/11 KO or caspase-3 KO mice, were resistant to PFT-induced death. We explored the mechanisms for PFT-induced necroptosis and determined that loss of ion homeostasis at the plasma membrane, mitochondrial damage, ATP depletion, and the generation of reactive oxygen species were together responsible. Treatment of mice with necrostatin-5, an inhibitor of RIP1; GW806742X, an inhibitor of MLKL; and necrostatin-5 along with co-enzyme Q10 (N5/C10), which enhances ATP production; reduced the severity of S. marcescens pneumonia in a mouse intratracheal challenge model. N5/C10 protected alveolar macrophages, reduced bacterial burden, and lessened hemorrhage in the lungs. We conclude that necroptosis is the major cell death pathway evoked by PFTs in macrophages and the necroptosis pathway can be targeted for disease intervention.  相似文献   
977.
We intended to evaluate the effects of different explants and growth regulators on callus induction and plant regeneration in garlic (Allium sativum L.). Furthermore, we intended to differentiate among different morphological types of callus by light microscopy and to relate them with their abilities to regenerate plants in the red-garlic cultivar 069. A factorial design with BDS—basal Dunstan and Short (1977)—medium, as a control and supplemented with 0.042, 0.42 and 4.24 μM picloram or with 0.045, 0.45 and 4.5 μM 2,4-D, in both cases with and without 4.43 μM N6-benzylaminopurine (BAP), was used. The cultures were grown in darkness at 25 ± 2°C and they were subcultured over a 6-month period. Basal plates and meristems were highly responsive explants, while immature umbels and root-tips were less responsive ones, as indicated by percentage of induced callus, growing callus and regenerating callus. The best response was 41% regenerating callus with 0.045 μM 2,4-D and BAP from basal plates while 57, 56 and 20% regenerating callus were obtained with 0.45 μM 2,4-D from meristems, root-tips and immature umbels, respectively. Also, these treatments showed a higher percentage of nodular and embryogenic callus (type I). Thus, it can be concluded that the use of meristems and 2,4-D will enhance callus production and quality, increase plant regeneration and allows to develop a protocol suitable for further transformation experiments in garlic.  相似文献   
978.
Phenotypic and genotypic characterization of 133 isolates of Neisseria meningitidis obtained from meningococcal disease cases in Argentina during 2010 were performed by the National Reference Laboratory as part of a project coordinated by the PAHO within the SIREVA II network. Serogroup, serotype, serosubtype and MLST characterization were performed. Minimum Inhibitory Concentration to penicillin, ampicillin, ceftriaxone, rifampin, chloramphenicol, tetracycline and ciprofloxacin were determined and interpreted according to CLSI guidelines. Almost 49% of isolates were W135, and two serotype:serosubtype combinations, W135∶2a:P1.5,2:ST-11 and W135∶2a:P1.2:ST-11 accounted for 78% of all W135 isolates. Serogroup B accounted for 42.1% of isolates, and was both phenotypically and genotypically diverse. Serogroup C isolates represented 5.3% of the dataset, and one isolate belonging to the ST-198 complex was non-groupable. Isolates belonged mainly to the ST-11 complex (48%) and to a lesser extent to the ST-865 (18%), ST-32 (9,8%) and the ST-35 complexes (9%). Intermediate resistance to penicillin and ampicillin was detected in 35.4% and 33.1% of isolates respectively. Two W135∶2a:P1.5,2:ST-11:ST-11 isolates presented resistance to ciprofloxacin associated with a mutation in the QRDR of gyrA gene Thr91-Ile. These data show serogroup W135 was the first cause of disease in Argentina in 2010, and was strongly associated with the W135∶2a:P1.5,2:ST-11 epidemic clone. Serogroup B was the second cause of disease and isolates belonging to this serogroup were phenotypically and genotypically diverse. The presence of isolates with intermediate resistance to penicillin and the presence of fluorquinolone-resistant isolates highlight the necessity and importance of maintaining and strengthening National Surveillance Programs.  相似文献   
979.
The early social environment can have substantial, lifelong effects on vertebrate social behaviour, which can be mediated by developmental plasticity of brain gene expression. Early‐life effects can influence immediate behavioural responses towards later‐life social challenges and can activate different gene expression responses. However, while genomic responses to social challenges have been reported frequently, how developmental experience influences the shape of these genomic reaction norms remains largely unexplored. We tested how manipulating the early social environment of juvenile cooperatively breeding cichlids, Neolamprologus pulcher, affects their behavioural and brain genomic responses when competing over a resource. Juveniles were reared either with or without a breeder pair and a helper. Fish reared with family members behaved more appropriately in the competition than when reared without. We investigated whether the different social rearing environments also affected the genomic responses to the social challenge. A set of candidate genes, coding for hormones and receptors influencing social behaviour, were measured in the telencephalon and hypothalamus. Social environment and social challenge both influenced gene expression of egr‐1 (early growth response 1) and gr1 (glucocorticoid receptor 1) in the telencephalon and of bdnf (brain‐derived neurotrophic factor) in the hypothalamus. A global analysis of the 11 expression patterns in the two brain areas showed that neurogenomic states diverged more strongly between intruder fish and control fish when they had been reared in a natural social setting. Our results show that same molecular pathways may be used differently in response to a social challenge depending on early‐life experiences.  相似文献   
980.
A ribosomal DNA region, including the entire 5.8S RNA gene and the internal transcribed spacers ITS 1 and ITS 2, was used for studying the phylogeny ofSalicaceae and the relationship betweenSalicaceae andFlacourtiaceae. The length of the ITS regions withinSalicaceae andFlacourtiaceae was similar to that found in other angiosperms. The GC content of both ITS regions was high, varying 62.7-72.2%. The most parsimonious tree clusters the wind-pollinatedChosenia bracteosa among theSalix species, suggesting that it should be included in the genusSalix. The grouping withinSalix leaves subg.Salix as paraphyletic, for which reason the subgeneric division is questionable.Populus was monophyletic and formed a sister group toSalix. The interspecific variation of the ITS sequences was very small inSalicaceae, which is in contradiction to the age of the group according to the evidence from fossil data.Idesia polycarpa fromFlacourtiaceae shows great sequence similarity withSalicaceae, but the analysis of 5.8S rDNA supports monophyly of the four species ofFlacourtiaceae sampled for this study.  相似文献   
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