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981.
Toll-like receptors (TLRs) mediate immune responses via the recognition of pathogen-associated molecular patterns (PAMPs), thus playing important roles in host defense. Among the chicken (Ch) TLR family, ChTLR3 and 7 have been shown to recognize viral RNA. In our earlier studies, we have reported polymorphisms of TLR1, 2, 4, 5, 15 and 21. In the present study, we amplified TLR3 and 7 genes from different chicken breeds and analyzed their sequences. We identified 7 amino acid polymorphism sites in ChTLR3 with 6 outer part sites and 1 inner part site, and 4 amino acid polymorphism sites in ChTLR7 with 3 outer part sites and 1 inner part site. These results demonstrate that ChTLR genes are polymorphic among different chicken breeds, suggesting a varied resistance across numerous chicken breeds. This information might help improve chicken health by breeding and vaccination. 相似文献
982.
983.
Benjamin Schwessinger Ofir Bahar Nicolas Thomas Nicolas Holton Vladimir Nekrasov Deling Ruan Patrick E. Canlas Arsalan Daudi Christopher J. Petzold Vasanth R. Singan Rita Kuo Mansi Chovatia Christopher Daum Joshua L. Heazlewood Cyril Zipfel Pamela C. Ronald 《PLoS pathogens》2015,11(3)
Plant plasma membrane localized pattern recognition receptors (PRRs) detect extracellular pathogen-associated molecules. PRRs such as Arabidopsis EFR and rice XA21 are taxonomically restricted and are absent from most plant genomes. Here we show that rice plants expressing EFR or the chimeric receptor EFR::XA21, containing the EFR ectodomain and the XA21 intracellular domain, sense both Escherichia coli- and Xanthomonas oryzae pv. oryzae (Xoo)-derived elf18 peptides at sub-nanomolar concentrations. Treatment of EFR and EFR::XA21 rice leaf tissue with elf18 leads to MAP kinase activation, reactive oxygen production and defense gene expression. Although expression of EFR does not lead to robust enhanced resistance to fully virulent Xoo isolates, it does lead to quantitatively enhanced resistance to weakly virulent Xoo isolates. EFR interacts with OsSERK2 and the XA21 binding protein 24 (XB24), two key components of the rice XA21-mediated immune response. Rice-EFR plants silenced for OsSERK2, or overexpressing rice XB24 are compromised in elf18-induced reactive oxygen production and defense gene expression indicating that these proteins are also important for EFR-mediated signaling in transgenic rice. Taken together, our results demonstrate the potential feasibility of enhancing disease resistance in rice and possibly other monocotyledonous crop species by expression of dicotyledonous PRRs. Our results also suggest that Arabidopsis EFR utilizes at least a subset of the known endogenous rice XA21 signaling components. 相似文献
984.
The prediction of conformational b-cell epitopes plays an important role in immunoinformatics. Several computational methods are proposed on the basis of discrimination determined by the solvent-accessible surface between epitopes and non-epitopes, but the performance of existing methods is far from satisfying. In this paper, depth functions and the k-th surface convex hull are used to analyze epitopes and exposed non-epitopes. On each layer of the protein, we compute relative solvent accessibility and four different types of depth functions, i.e., Chakravarty depth, DPX, half-sphere exposure and half space depth, to analyze the location of epitopes on different layers of the proteins. We found that conformational b-cell epitopes are rich in charged residues Asp, Glu, Lys, Arg, His; aliphatic residues Gly, Pro; non-charged residues Asn, Gln; and aromatic residue Tyr. Conformational b-cell epitopes are rich in coils. Conservation of epitopes is not significantly lower than that of exposed non-epitopes. The average depths (obtained by four methods) for epitopes are significantly lower than that of non-epitopes on the surface using the Wilcoxon rank sum test. Epitopes are more likely to be located in the outer layer of the convex hull of a protein. On the benchmark dataset, the cumulate 10th convex hull covers 84.6% of exposed residues on the protein surface area, and nearly 95% of epitope sites. These findings may be helpful in building a predictor for epitopes. 相似文献
985.
甘蓝型油菜Fad2与Fae1基因双干扰RNAi载体的构建 总被引:1,自引:0,他引:1
将来源于甘蓝型油菜XY15的Fad2与Fae1基因编码区,长度分别为349bp和426bp的两个保守序列片段连接成807bp的大片段。然后分别以正反向插入到pFGC5941干扰载体查耳酮合成酶内含子的两端,构建成RNAi载体。以期在菜籽中转录后能有效抑制Fad2与Fae1两个基因的表达。所构建的RNAi载体最终序列全长3kb,经限制性内切酶消化、PCR扩增验证和序列测定,证明目标序列与GenBank数据库中的碱基序列一致,并且为正反向插入到pFGC5941载体上。通过农杆菌介导的油菜转化,已获得油菜抗性再生植株144个。 相似文献
986.
987.
Involvement of PDCD5 in the regulation of apoptosis in fibroblast-like synoviocytes of rheumatoid arthritis 总被引:1,自引:0,他引:1
Wang N Lu HS Guan ZP Sun TZ Chen YY Ruan GR Chen ZK Jiang J Bai CJ 《Apoptosis : an international journal on programmed cell death》2007,12(8):1433-1441
Apoptosis is reduced in the synovial tissue of patients with rheumatoid arthritis (RA), possibly due to decreased expression
of pro-apoptotic genes. Programmed Cell Death 5 (PDCD5) has been recently identified as a protein that mediates apoptosis.
Although PDCD5 is down-regulated in many human tumors, the role of PDCD5 in RA has not been investigated. Here we report that
reduced levels of PDCD5 mRNA and protein are detected in RA synovial tissue (ST) and fibroblast-like synoviocytes (FLS) than
in tissue and cells from patients with osteoarthritis (OA). We also report differences in the PDCD5 expression pattern in
tissues from patients with these two types of arthritis. PDCD5 showed a scattered pattern in rheumatoid synovium compared
with OA, in which the protein labeling was stronger in the synovial lining layer than in the sublining. We also observed increased
expression and nuclear translocation of PDCD5 in RA patient-derived FLS undergoing apoptosis. Finally, overexpression of PDCD5
led to enhanced apoptosis and activation of caspase-3 in triptolide-treated FLS. We propose that PDCD5 may be involved in
the pathogenesis of RA. These data also suggest that PDCD5 may serve as a therapeutic target to enhance sensitivity to antirheumatic
drug-induced apoptosis in RA. 相似文献
988.
Shan-Shan Yu Ming Wang Xin-Mei Li Wei-Heng Chen Ju-Tao Chen Hui-Li Wang Di-Yun Ruan 《BMC developmental biology》2007,7(1):51
Background
Previous study has demonstrated that dietary taurine supplement protected rats from impairments of synaptic plasticity induced by postnatal lead exposure. However, little is known about the role of taurine in the presence of prenatal and perinatal lead exposure. We investigated the possible effect of taurine supplement on prenatal and perinatal lead-induced synaptic plasticity deficit and determined developmental periods critical for the effect of taurine. 相似文献989.
Zhao XY Liang SF Yao SH Ma FX Hu ZG Yan F Yuan Z Ruan XZ Yang HS Zhou Q Wei YQ 《Biochemical and biophysical research communications》2007,361(1):74-78
Xenopus laevis has recently been determined as a novel study platform of gene function. In this study, we cloned Xenopus DRR1 (xDRR1), which is homologous to human down-regulated in renal carcinoma (DRR1) gene. Bioinformatics analysis for DRR1 indicated that xDRR1 shared 74% identity with human DRR1 and 66% with mouse DRR1, and the phlogenetic tree of DRR1 protein was summarized. The xDRR1 gene locates in nuclei determined by transfecting A549 cells with the recombinant plasmid pEGFP-N1/xDRR1. RT-PCR analysis revealed that xDRR1 gene was expressed in all stages of early embryo development and all kinds of detected tissues, and whole-mount in situ hybridization showed xDRR1 was mainly present along ectoderm and mesoderm. Furthermore, xDRR1 expression could suppress A549 cell growth by transfecting with plasmid pcDNA3.1(+)/xDRR1. xDRR1 probably plays important roles involving in cell growth regulation and Xenopus embryo development. 相似文献
990.
Ruan Yun-Zhen 《植物分类学报:英文版》1988,26(6):443-449
In the classification of J. D. Hooker (1873) and of K. Schumann (1891),
the genus Prismatomeris Thw. is included in the tribe Morindeae of Rubiaceae. In the modern classifications, e. g. Bremekamp (1966), however, the taxonomic position of the genus is
still uncertain. The genus agrees with the tribe Morindeae in the downward radicle, valvate
aestivation of the corolla lobes and presence of raphides, but it differs significantly from the
latter in the free flowers, bilocular ovary and the peltate ovule attached to the upper half of
septum. Therefore, it would be more suitable that the genus is separated from the tribe Morindeae Miq., and is raised to the rank of tribe, placed in the subfamily Rubioideae based on
Bremekamp’s delimitation.
In the present paper ten character pairs of the genus and the notes on their taxonomic
value are presented and two following species are recognized:
1. P. tetrandra (Roxb.) K. Schum. is found in northern India. Its subspecies,
which is distributed in Yunnan of China and in Thailand, was previously called P. tetrandra (Roxb.) K. Schumann, and is now revised as P. tetrandra (Roxb.) K. Schum.
subsp. multiflora (Ridley) Y. Z. Ruan.
2. P. connata Y.Z. Ruan is described as a new species, that has been treated as P.
tetrandra (Roxb.) K. Schum. by previous auth rs. It is native to the subtropic region of South
China. Its tropical new subspecies, P. connata. Y. Z. Ruan subsp. hainanensis Y. Z.
Ruan, is found on Hainan Island. 相似文献