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991.
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993.
Tungtrakoolsub P Noda T Morozumi T Hamasima N Kobayashi E Ueda J Watanabe T 《Animal genetics》2008,39(1):22-27
The porcine MX1 and MX2 promoters were characterized in this study. Sequencing of the 332-bp MX1 promoter region identified 15 substitutions and insertions at three positions in 21 pigs from 15 breeds, in which nine genotypes were classified. Among the nine genotypes, no statistically significant differences in the promoter activities were observed after interferon (IFN- α 2b) treatment of transiently transfected cells containing constructs with luciferase reporter plasmids. The 341-bp MX2 promoter region contained regulatory sequences for ISRE, GC box, Sp1 and AP-1, as well as a TATA box. Nucleotide sequences of the MX2 promoter region revealed four substitutions and one deletion, in which six genotypes were classified. Among the six genotypes, a statistically significant difference ( P < 0.05) in MX2 promoter activities after IFN- α 2b treatment was detected in transiently transfected cells. 相似文献
994.
995.
Kasraie S Houshmand M Banoei MM Ahari SE Panahi MS Shariati P Bahar M Moin M 《Cellular and molecular neurobiology》2008,28(7):933-938
Huntington disease (HD) is a genetically dominant condition caused by expanded CAG repeats which code for glutamine in the
HD gene product, huntingtin. Huntingtin is expressed in almost all tissues, so abnormalities outside the brain can also be
expected. Involvement of nuclei and mitochondria in HD pathophysiology has been suggested. In fact mitochondrial dysfunction
is reported in brains of patients suffering from HD. The tRNA gene mutations are one of hot spots that can cause mitochondrial
disorders. In this study, possible mitochondrial DNA (mtDNA) damage was evaluated by screening for mutations in the tRNAleu/lys and ATPase 6 genes of 20 patients with HD, using PCR and automated DNA sequencing. Mutations including an A8656G mutation
in one patient were observed, which may be causal to the disease. Understanding the role of mitochondria in the pathogenesis
of neurodegenerative diseases could potentially be important for the development of therapeutic strategies in HD. 相似文献
996.
997.
Three heat shock protein (HSP) genes (hsp70, hsc70, hsp90) were partially cloned from the brown planthopper Nilaparvata lugens and the small brown planthopper Laodelphax striatellus (Homoptera: Delphacidae), which are serious pests of the rice plant. Sequence comparisons at the deduced amino acid level showed that the three HSPs of planthoppers were most homologous to corresponding HSPs of dipteran and lepidopteran species. Identities of both heat shock cognate 70 and HSP90 were higher than HSP70 in both species. Identity of the HSP70 between the two planthopper species was only 81%, a value much lower than seen among fly and moth groups. Effects of heat and cold shocks were demonstrated on expression of the three hsp genes in the two planthopper species. Heat shock (40 ℃) upregulated the hsp90 level but did not change the hsc70 level in either the nymph and adult stages of either species. On the other hand, the hsp70 level was only upregulated in L. striatellus. This heat shock response was prompt and lasted only for 1 h after treatment. In contrast, cold shock at 4℃ did not change the expression levels of any hsp in either species. 相似文献
998.
目的分析金黄色葡萄球菌所致肺部感染的耐药性特点及其Panton—Valentine杀白细胞素基因的携带状况。方法回顾性调查了温州医学院第一附属医院2005年1月至2006年1月医院感染的金黄色葡萄球菌所致肺部感染患者132例,对其体外药敏试验进行分析;并利用多重PCR检测其PVL基因,应用多位点基因序列分型(multilocus sequence typing,MLST)技术对PVL基因阳性的菌株进行序列分型。耐甲氧西林金黄色葡萄球菌(methicillin-resistant Staphylococcus aureus,MRSA)的SCCmec基因分型采用多重聚合酶链反应。结果致肺部感染的132株金黄色葡萄球菌的耐药现象较为严重,仅对万古霉素、呋喃妥因及复方新诺明等药物的敏感率较高;其中经多重PCR筛选出10株携带PVL基因的金葡菌,全部为MRSA菌株,3株为ST239-SCCⅢ,2株为ST398-SCCmecⅢ,2株为ST398-SCCmecⅣ,ST25-SCCmecⅢ、ST59-SCCmecⅠ和ST88-SCCmecⅢ各1株。结论肺部感染的金黄色葡萄球菌对多种抗生素耐药,呈多重耐药性;其携带PVL基因占一定比例。 相似文献
999.
Hasan M Friedt W Pons-Kühnemann J Freitag NM Link K Snowdon RJ 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2008,116(8):1035-1049
Breeding of oilseed rape (Brassica napus ssp. napus) has evoked a strong bottleneck selection towards double-low (00) seed quality with zero erucic acid and low seed glucosinolate
content. The resulting reduction of genetic variability in elite 00-quality oilseed rape is particularly relevant with regard
to the development of genetically diverse heterotic pools for hybrid breeding. In contrast, B. napus genotypes containing high levels of erucic acid and seed glucosinolates (++ quality) represent a comparatively genetically
divergent source of germplasm. Seed glucosinolate content is a complex quantitative trait, however, meaning that the introgression
of novel germplasm from this gene pool requires recurrent backcrossing to avoid linkage drag for high glucosinolate content.
Molecular markers for key low-glucosinolate alleles could potentially improve the selection process. The aim of this study
was to identify potentially gene-linked markers for important seed glucosinolate loci via structure-based allele-trait association
studies in genetically diverse B. napus genotypes. The analyses included a set of new simple-sequence repeat (SSR) markers whose orthologs in Arabidopsis thaliana are physically closely linked to promising candidate genes for glucosinolate biosynthesis. We found evidence that four genes
involved in the biosynthesis of indole, aliphatic and aromatic glucosinolates might be associated with known quantitative
trait loci for total seed glucosinolate content in B. napus. Markers linked to homoeologous loci of these genes in the paleopolyploid B. napus genome were found to be associated with a significant effect on the seed glucosinolate content. This example shows the potential
of Arabidopsis-Brassica comparative genome analysis for synteny-based identification of gene-linked SSR markers that can potentially be used in marker-assisted
selection for an important trait in oilseed rape.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
1000.
Genomic location and characterisation of MIC genes in cattle 总被引:1,自引:0,他引:1
Major histocompatibility complex (MHC) class I chain-related (MIC) genes have been previously identified and characterised in human. They encode polymorphic class I-like molecules that are stress-inducible, and constitute one of the ligands of the activating natural killer cell receptor NKG2D. We have identified three MIC genes within the cattle genome, located close to three non-classical MHC class I genes. The genomic position relative to other genes is very similar to the arrangement reported in the pig MHC region. Analysis of MIC cDNA sequences derived from a range of cattle cell lines suggest there may be four MIC genes in total. We have investigated the presence of the genes in distinct and well-defined MHC haplotypes, and show that one gene is consistently present, while configuration of the other three genes appears variable. 相似文献