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1.
Genome-wide analysis of the SET DOMAIN GROUP family in grapevine 总被引:1,自引:0,他引:1
The SET DOMAIN GROUP (SDG) proteins represent an evolutionarily-conserved family of epigenetic regulators present in eukaryotes
and are putative candidates for the catalysis of lysine methylation in histones. Plant genomes analyses of this family have
been performed in arabidopsis, maize, and rice and functional studies have shown that SDG genes are involved in the control
of plant development. In this work, we describe the identification and structural characterization of SDG genes in the Vitis vinifera genome. This analysis revealed the presence of 33 putative SDG genes that can be grouped into different classes, as it has
been previously described for plants. In addition to the SET domain, the proteins identified possessed other domains in the
different classes. As part of our study regarding the growth and development of grapevine, we selected eight genes and their
expression levels were analyzed in representative vegetative and reproductive organs of this species. The selected genes showed
different patterns of expression during inflorescence and fruit development, suggesting that they participate in these processes.
Furthermore, we showed that the expression of selected SDGs changes during viral infection, using as a model Grapevine Leafroll
Associated Virus 3-infected symptomatic grapevine leaves and fruits. Our results suggest that developmental changes caused
by this virus could be the result of alterations in SDG expression. 相似文献
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Defective receptor binding of low density lipoprotein from pigs possessing mutant apolipoprotein B alleles 总被引:1,自引:0,他引:1
S W Lowe W J Checovich J Rapacz A D Attie 《The Journal of biological chemistry》1988,263(30):15467-15473
We previously identified a defect in the in vivo catabolism of low density lipoprotein (LDL) from hypercholesterolemic pigs carrying a mutant apolipoprotein B allele. In the present studies, we examined the in vitro metabolism of mutant LDL in cultured pig fibroblasts. A 3-fold higher concentration of mutant LDL (compared to control) was needed to displace 50% of control 125I-LDL binding. Mutant LDL had a 6-fold higher dissociation constant than control LDL. Scatchard plots of the binding data were concave upward, suggesting multiple classes of binding sites or negative cooperativity. The mutant LDL degradation rate was reduced by 40%; this decrease could be attributed to a dense LDL subspecies. Mutant and control buoyant LDL subspecies were degraded more slowly than the corresponding dense LDL subspecies. Together, these studies show that diminished LDL receptor binding can result from mutations in apolipoprotein B and from changes in the lipid composition of LDL particles. 相似文献
5.
A radioiodinated, intracellularly trapped ligand for determining the sites of plasma protein degradation in vivo. 总被引:22,自引:6,他引:16 下载免费PDF全文
R C Pittman T E Carew C K Glass S R Green C A Taylor Jr A D Attie 《The Biochemical journal》1983,212(3):791-800
We recently developed a general method for determining tissue sites of degradation of plasma proteins in vivo that made use of covalently attached radioactive sucrose. On degradation of the protein, the sucrose remained trapped in the cells as a cumulative marker of protein degradation. The method described here depends on the same principles, but uses an adduct of cellobiose and tyramine that is radioiodinated to high specific radioactivity and then covalently attached to protein. Use of the radioiodinated ligand increases the sensitivity of the method at least 100-fold and allows simplified tissue analysis. Proteins derivatized with the radioiodinated ligand were recognized as underivatized proteins both in vitro and in vivo. On degradation of derivatized low-density lipoprotein, the rate of leakage from cultured fibroblasts was only 5% during 24 h. Similarly, on injection of labelled proteins into rats and rabbits, urinary excretion of the label was in all cases less than 10% of total labelled catabolic products recovered 24 h after injection. Examination of the tissue contents of label at two times after injection of labelled asialofetuin or apolipoprotein A1 in rats, and asialotransferrin in rabbits showed that the label did not detectably redistribute between tissues after initial uptake and catabolism; a significant leakage from liver was quantitatively accounted for by label appearing in gut contents and faeces. A simple double-label method was devised to provide a correction for intact protein in trapped plasma, the extravascular spaces, and within cells. By using this method it becomes unnecessary to fractionate tissue samples. 相似文献
6.
Adelina A. Davies Stephen E. Moss Mark R. Crompton Tania A. Jones Nigel K. Spurr Denise Sheer Christine Kozak Michael J. Crumpton 《Human genetics》1989,82(3):234-238
Summary The gene encoding a tissue inhibitor of metalloproteinases, TIMP, has previously been shown to be X-linked in both the human and mouse genomes. We have used a series of somatic cell hybrids segregating translocation and deletion X chromosomes to map the TIMP gene on the human X chromosome. In combination with previous data, the gene can be assigned to Xp11.23Xp11.4. Genetic linkage analyses demonstrate that TIMP is linked to the more distal ornithine transcarbamylase (OTC) locus at a distance of about 22 centimorgans. The data are consistent with the conclusion that TIMP maps to a conserved synteny and linkage group on the proximal short arm of the human X chromosome and on the pericentric region of the mouse X chromosome, including loci for synapsin-1, a member of the raf oncogene family, OTC, and TIMP. 相似文献
7.
Isozyme analysis of Galaxias species (Teleostei: Galaxiidae) from the Taieri River, South Island, New Zealand: a species complex revealed 总被引:2,自引:0,他引:2
Richard M. Allibone Todd A. Crowl Jean M. Holmes Tania M. King Robert M. McDowall Colin R. Townsend Graham P. Wallis 《Biological journal of the Linnean Society. Linnean Society of London》1996,57(2):107-127
We examined genetic differentiation among 23 samples of non-migratory river galaxias from 17 streams in the Taieri River system, South Island, New Zealand. Four major genetic types were found, two of which occur in narrow sympatry in one location. These were compared with topotypical material representing Galaxias anomalus from the Clutha system (Otago) and G. vulgaris from the Waimakariri system (Canterbury) in order to establish identity. Morphological examination of these four major genetic types revealed consistent concomitant differences. The results suggest that there are at least three species of river galaxias in the Taieri system: G. anomalus, G. vulgaris and at least one previously undescribed species. We propose that the genetic structuring and subsequent speciation of this group has been promoted by the absence of the marine juvenile phase that is found in five other members of the genus native to New Zealand. This structuring may be exacerbated by population fragmentation over the last century owing to the negative influence of introduced trout. The phylogenetic diversity within the river system mirrors the diverse flora and invertebrate fauna of the region, and has conservation implications that parallel those resulting from our improved knowledge of the New Zealand herpetofauna through the application of genetic analysis. 相似文献
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David J. Munroe Melanie Haas Eva Bric Tania Whitton Hiroyuki Aburatani Kent Hunter David Ward David E. Housman 《Genomics》1994,19(3)
A significant issue in the analysis of any genomic DNA segment is the generation of a unique set of short single-copy sequences that are representative of that region. In this report we describe a novel technique, IRE-bubble PCR, which was designed to amplify the human DNA content of somatic cell hybrids, YACs, cosmids, and λ phage and result in greater complexity and representation than standard inter-IRE, PCR. Here we demonstrate that IRE-bubble PCR is species specific and that it results in the generation of a product that is at least 10-fold more complex and representative than that produced by standard inter-IRE PCR. In addition, we have addressed the factors that contribute to the representation of the IRE-bubble PCR product and show how they may be used to further increase the complexity of this reaction. Finally, we have illustrated how the complexity and distribution of products generated by IRE-bubble PCR can be exploited and applied to FISH mapping and "chromosome painting" as well as to the generation of STSs targeted to specific chromosomal or subchromosomal regions. 相似文献