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11.
Bermek O Diamantopoulou Z Polykratis A Dos Santos C Hamma-Kourbali Y Burlina F Delbé J Chassaing G Fernig DG Katsoris P Courty J 《Experimental cell research》2007,313(19):4041-4050
Heparin affin regulatory peptide (HARP) is an 18 kDa heparin-binding protein that plays a key role in tumor growth. We showed previously that the synthetic peptide P(111-136) composed of the last 26 HARP amino acids inhibited HARP-induced mitogenesis. Here, to identify the exact molecular domain involved in HARP inhibition, we investigated the effect of the shorter basic peptide P(122-131) on DU145 cells, which express HARP and its receptor protein tyrosine phosphatase beta/zeta (RPTPbeta/zeta). P(122-131) was not cytotoxic; it dose-dependently inhibited anchorage-independent growth of DU145 cells. Binding studies using biotinylated P(122-131) indicated that this peptide interfered with HARP binding to DU145 cells. Investigation of the mechanisms involved suggested interference, under anchorage-independent conditions, of P(122-131) with a HARP autocrine loop in an RPTPbeta/zeta-dependent fashion. Thus, P(122-131) may hold potential for the treatment of disorders involving RPTPbeta/zeta. 相似文献
12.
Lívia Santos Lima Karina Peres Gramacho José Luis Pires Didier Clement Uilson Vanderlei Lopes Nicolas Carels Abelmon da Silva Gesteira Fernanda Amato Gaiotto Júlio Cézar de Mattos Cascardo Fabienne Micheli 《Tree Genetics & Genomes》2010,6(5):663-676
In this study, we report results of the detection and analysis of SSR markers derived of cacao–Moniliophthora perniciosa expressed sequence tags (ESTs) in relation to cacao resistance to witches’ broom disease (WBD), and we compare the polymorphism
of those ESTs (EST-simple sequence repeat (SSR)) with classical neutral SSR markers. A total of 3,487 ESTs was used in this
investigation. SSRs were identified in 430 sequences: 277 from the resistant genotype TSH 1188 and 153 from the susceptible
one Catongo, totalizing 505 EST-SSRs with three types of motifs: dinucleotides (72.1%), trinucleotides (27.3%), and tetranucleotides
(0.6%). EST-SSRs were classified into 16 main categories; most of the EST-SSRs belonged to “Unknown function” and “No homology”
categories (45.82%). A high frequency of SSRs was found in the 5’UTR and in the ORF (about 27%) and a low frequency was observed
in the 3’UTR (about 8%). Forty-nine EST-SSR primers were designed and evaluated in 21 cacao accessions, 12 revealed polymorphism,
having 47 alleles in total, with an average of 3.92 alleles per locus. On the other hand, the 11 genomic SSR markers revealed
a total of 47 alleles, with an average of 5.22 alleles per locus. The association of EST-SSR with the genomic SSR enhanced
the analysis of genetic distance among the genotypes. Among the 12 polymorphic EST-SSR markers, two were mapped on the F2 Sca 6 × ICS 1 population reference for WBD resistance. 相似文献
13.
14.
Habitat fragmentation is known to generally reduce the size of plant populations and increase their isolation, leading to
genetic erosion and increased between-population genetic differentiation. In Flanders (northern Belgium) Primula vulgaris is very rare and declining. Populations have incurred strong fragmentation for the last decades and are now restricted to
a few highly fragmented areas in an intensively used agricultural landscape. Previous studies showed that small populations
of this long-lived perennial herb still maintained high levels of genetic variation and low genetic differentiation. This
pattern can either indicate recent gene flow or represent historical variation. Therefore, we used polymorphic microsatellite
loci to investigate genetic variation and structure in adult (which may still reflect historical variation) and seedling (recent
generation, thus affected by current processes) life stages. The recent generation (seedlings) showed a significant loss of
observed heterozygosity (H
o) together with lower expected heterozygosity (H
e), a trend for higher inbreeding levels (F
IS) and higher differentiation (F
ST) between populations compared to the adult generation. This might result from (1) a reduction in effective population size,
(2) higher inbreeding levels in the seedlings, (3) a higher survival of heterozygotes over time due to a higher fitness of
heterozygotes (heterosis) and/or a lower fitness of homozygotes (inbreeding depression), (4) overlapping generations in the
adult life stage, or (5) a lack of establishment of new (inbred) adults from seedlings due to degraded habitat conditions.
Combining restoration of both habitat quality and gene flow between populations may be indispensable to ensure a sustainable
conservation of fragmented populations. 相似文献
15.
16.
Suzanne Peyrottes Béatrice Mestre Fabienne Burlina Michael J. Gait 《Nucleosides, nucleotides & nucleic acids》2013,32(6-7):1443-1448
Abstract We describe a peptide fragment, solid-phase coupling strategy for synthesis of peptide-oligonucleotide conjugates. Model conjugates contained a hydrophobic tetrapeptide, a hydrophobic influenza virus fusion nonapeptide, or a basic octapeptide of the HIV-1 Tat protein coupled to either dT12 or a 16-mer anti-Tat oligodeoxyribonucleotide. Conjugation yields were improved by removal of internucleotide 2-cyanoethyl groups prior to peptide coupling and by use of a C12 spacer between peptide and oligonucleotide. 相似文献
17.
Mazen Amatoury Vera Merheb Jessica Langer Xin Maggie Wang Russell Clive Dale Fabienne Brilot 《Journal of visualized experiments : JoVE》2013,(81)
Over the recent years, antibodies against surface and conformational proteins involved in neurotransmission have been detected in autoimmune CNS diseases in children and adults. These antibodies have been used to guide diagnosis and treatment. Cell-based assays have improved the detection of antibodies in patient serum. They are based on the surface expression of brain antigens on eukaryotic cells, which are then incubated with diluted patient sera followed by fluorochrome-conjugated secondary antibodies. After washing, secondary antibody binding is then analyzed by flow cytometry. Our group has developed a high-throughput flow cytometry live cell-based assay to reliably detect antibodies against specific neurotransmitter receptors. This flow cytometry method is straight forward, quantitative, efficient, and the use of a high-throughput sampler system allows for large patient cohorts to be easily assayed in a short space of time. Additionally, this cell-based assay can be easily adapted to detect antibodies to many different antigenic targets, both from the central nervous system and periphery. Discovering additional novel antibody biomarkers will enable prompt and accurate diagnosis and improve treatment of immune-mediated disorders. 相似文献
18.
Constanze Hartmann Fabienne Mayenzet Jean-Paul Larcinese Olivier P. Haefliger Andrea Buettner Christian Starkenmann 《Steroids》2013,78(2):156-160
A method was developed for the quantification of 5-α-androst-16-en-3-one in human breast milk based on application of a stable isotope dilution assay using 5α-androst-16-en-3-one-6, 6-d2. The procedure includes extraction of the human milk by hexane with subsequent clean-up of the obtained extract by gel permeation and silica gel column chromatography. The extracted samples were analyzed by gas chromatography–mass spectrometry. Using this method 5-α-androst-16-en-3-one could be identified and for the first time quantified in a concentration range of 26–155 ng/kg in human milk. 相似文献
19.
20.
Frédéric Plewniak Sandrine Koechler Benjamin Navet Éric Dugat‐Bony Olivier Bouchez Pierre Peyret Fabienne Séby Fabienne Battaglia‐Brunet Philippe N. Bertin 《Molecular ecology》2013,22(19):4870-4883
Microorganisms dwelling in sediments have a crucial role in biogeochemical cycles and are expected to have a strong influence on the cycle of arsenic, a metalloid responsible for severe water pollution and presenting major health risks for human populations. We present here a metagenomic study of the sediment from two harbours on the Mediterranean French coast, l'Estaque and St Mandrier. The first site is highly polluted with arsenic and heavy metals, while the arsenic concentration in the second site is below toxicity levels. The goal of this study was to elucidate the potential impact of the microbial community on the chemical parameters observed in complementary geochemical studies performed on the same sites. The metagenomic sequences, along with those from four publicly available metagenomes used as control data sets, were analysed with the RAMMCAP workflow. The resulting functional profiles were compared to determine the over‐represented Gene Ontology categories in the metagenomes of interest. Categories related to arsenic resistance and dissimilatory sulphate reduction were over‐represented in l'Estaque. More importantly, despite very similar profiles, the identification of specific sequence markers for sulphate‐reducing bacteria and sulphur‐oxidizing bacteria showed that sulphate reduction was significantly more associated with l'Estaque than with St Mandrier. We propose that biotic sulphate reduction, arsenate reduction and fermentation may together explain the higher mobility of arsenic observed in l'Estaque in previous physico‐chemical studies of this site. This study also demonstrates that it is possible to draw sound conclusions from comparing complex and similar unassembled metagenomes at the functional level, even with very low sequence coverage. 相似文献