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Magatti M De Munari S Vertua E Parolini O 《Journal of cellular and molecular medicine》2012,16(9):2208-2218
Cells derived from the amniotic foetal membrane of human term placenta have drawn particular attention mainly for their plasticity and immunological properties, which render them interesting for stem-cell research and cell-based therapeutic applications. In particular, we have previously demonstrated that amniotic mesenchymal tissue cells (AMTC) inhibit lymphocyte proliferation in vitro and suppress the generation and maturation of monocyte-derived dendritic cells. Here, we show that AMTC also significantly reduce the proliferation of cancer cell lines of haematopoietic and non-haematopoietic origin, in both cell-cell contact and transwell co-cultures, therefore suggesting the involvement of yet-unknown inhibitory soluble factor(s) in this 'cell growth restraint'. Importantly, we provide evidence that the anti-proliferative effect of AMTC is associated with induction of cell cycle arrest in G0/G1 phase. Gene expression analyses demonstrate that AMTC can down-regulate cancer cells' mRNA expression of genes associated with cell cycle progression, such as cyclins (cyclin D2, cyclin E1, cyclin H) and cyclin-dependent kinase (CDK4, CDK6 and CDK2), whilst they up-regulate cell cycle negative regulator such as p15 and p21, consistent with a block in G0/G1 phase with no progression to S phase. Taken together, these findings warrant further studies to investigate the applicability of these cells for controlling cancer cell proliferation in vivo. 相似文献
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Christian G. Ramos André M. Grilo Sílvia A. Sousa Marta L. Barbosa Helena Nadais Jorge H. Leitão 《Applied microbiology and biotechnology》2010,85(3):801-806
This work describes a methodology combining DNA extraction, polymerase chain reaction amplification with primers targeting 16S ribosomal RNA genes, cloning, and sequencing of clones previously analyzed by restriction fragment length polymorphism (RFLP), which can be applied to study the microbial diversity in a given habitat. The methodology allows the minimization of the sequencing effort, which is particularly relevant when analyzing large numbers of clones. The methodology does not require particularly skilled personnel and can easily be adaptable to the molecular characterization of virtually any particular microbial population, provided that both adequate primers and suitable restriction enzymes for RFLP analysis of the clone library have been chosen. An example of application is presented, in which a sample taken from a continuously operating upflow anaerobic sludge blanket reactor was analyzed. RFLP analysis of the initial 162 clones with HaeIII allowed the identification of only 28 distinct profiles. As expected, identical RFLP profiles corresponded to identical nucleotide sequences. 相似文献
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Charlotte Noyer Gemma Agell Marta Pascual Mikel A. Becerro 《Conservation Genetics》2009,10(6):1895-1898
The abundance of the bath sponge Spongia agaricina has decreased drastically in recent years and it is now considered an endangered species under Annex 3 of Bern and Barcelona
conventions. We describe eight microsatellite markers and present data on their allelic variation and utility as high resolution
genetic markers. We analyzed 36 individuals from two populations and found that the number of alleles per locus ranged between
1 and 7. Observed heterozygosity ranged from 0 to 0.72. We found deviations from Hardy–Weinberg expectations for some loci.
We exclusively detected null alleles for those loci that deviated from Hardy–Weinberg expectations. Also, distributions of
allele frequencies differed significantly between the two populations, making them suitable for population genetic analyses. 相似文献
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Barral P Tejera ML Treviño MA Batanero E Villalba M Bruix M Rodríguez R 《Protein expression and purification》2004,37(2):1259-343
Olive pollen is one of the main causes of allergy in Mediterranean countries. Ole e 6, an olive pollen allergen, is a small (5.8 kDa) and acidic protein (pI 4.2) and no homologous proteins have been isolated or characterized so far. Ole e 6 has been efficiently expressed in the methylotrophic yeast Pichia pastoris. The cDNA encoding Ole e 6 was inserted into the plasmid vector pPIC9 and overexpressed in GS115 yeast cells. The recombinant product was purified by size-exclusion chromatography followed by reverse-phase HPLC. N-terminal sequencing, amino acid composition analysis, CD, NMR, and IgG-binding experiments were employed to characterize the purified protein. NMR data revealed the oxidation of the methionine at position 28 in approximately 50% of the recombinant protein but, although this alters its electrophoretic behavior, it did not affect folding or IgG-binding properties of rOle e 6. The recombinant form of Ole e 6 expressed in P. pastoris can be employed for structural and biochemical studies. 相似文献
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Alda M Luciano JV Andrés E Serrano-Blanco A Rodero B del Hoyo YL Roca M Moreno S Magallón R García-Campayo J 《Arthritis research & therapy》2011,13(5):R173