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71.
72.
73.
Walley PG Carder J Skipper E Mathas E Lynn J Pink D Buchanan-Wollaston V 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2012,124(3):467-484
A unique broccoli × broccoli doubled haploid (DH) population has been created from the F1 of a cross between two DH broccoli lines derived from cultivars Green Duke and Marathon. We genotyped 154 individuals from
this population with simple sequence repeat and amplified fragment length polymorphism markers to create a B. oleracea L. var. italica ‘intra-crop’ specific framework linkage map. The map is composed of nine linkage groups with a total length of 946.7 cM.
Previous published B. oleracea maps have been constructed using diverse crosses between morphotypes of B. oleracea; this map therefore represents a useful breeding resource for the dissection of broccoli specific traits. Phenotype data
have been collected from the population over five growing seasons; the framework linkage map has been used to locate quantitative
trait loci for agronomically important broccoli traits including head weight (saleable yield), head diameter, stalk diameter,
weight loss and relative weight loss during storage, as well as traits for broccoli leaf architecture. This population and
associated linkage map will aid breeders to directly map agronomically important traits for the improvement of elite broccoli
cultivars. 相似文献
74.
The expression of cDNA clones of yeast M1 double-stranded RNA in yeast confers both killer and immunity phenotypes. 总被引:9,自引:0,他引:9 下载免费PDF全文
Two cDNA clones of the segment of Saccharomyces cerevisiae M1 double-stranded RNA, which codes for the yeast killer toxin, have been expressed in yeast using the expression vector pYT760. Toxin expression and secretion depended upon the presence of a yeast promoter. Transformants not only contain an authentic preprotoxin precursor, as determined by precipitation of intracellular proteins with antitoxin antisera, but also display an immunity phenotype. The evidence is that the immunity protein is part of the preprotoxin and may act by masking toxin binding sites. Neither cDNA clone had a complete 5' terminus and the preprotoxin translational start was missing. The promoter and the initiator ATG were supplied by the expression vector. One clone with a full-length preprotoxin but altered N-terminal amino acids gave a normal glycosylated intracellular precursor. A clone with an N-terminal nine amino acid deletion gave a precursor which was not glycosylated but toxin was still secreted. 相似文献
75.
Stimulation of fatty acid synthesis in vitro by gonadotrophin-induced testicular ribonucleic acid 下载免费PDF全文
RNA from testes of hypophysectomized rats treated with follicle-stimulating hormone and luteinizing hormone markedly stimulates in vitro the incorporation of acetate and malonate (as CoA derivatives) into polyunsaturated fatty acids. The system in vitro contains the components necessary for both protein and fatty acid synthesis. That the RNA is a hormone-induced messenger type that causes enzyme synthesis that then causes fatty acid synthesis is supported by the following observations: (1) the stimulation of RNA synthesis by follicle-stimulating hormone and luteinizing hormone is decreased by injection of the animals with actinomycin D; (2) puromycin in the system in vitro decreases the synthesis of polyunsaturated fatty acids; (3) the activity of the RNA preparation is destroyed by digestion with ribonuclease; in fact, the digest is inhibitory, which is a characteristic of messenger-RNA-mediated protein synthesis; (4) protein that might be denatured enzyme is virtually absent from the effective RNA preparations. 相似文献
76.
The divergent domains of the NEFA and nucleobindin proteins are derived from an EF-hand ancestor 总被引:2,自引:0,他引:2
Karabinos A; Bhattacharya D; Morys-Wortmann C; Kroll K; Hirschfeld G; Kratzin HD; Barnikol-Watanabe S; Hilschmann N 《Molecular biology and evolution》1996,13(7):990-998
The human protein NEFA (DNA binding, EF-hand, Acidic region) has previously
been isolated from a KM3 cell line and immunolocalized on the plasma
membrane, in the cytoplasma, and in the culture medium. Sequence analysis
of a cDNA clone encoding NEFA identified a hydrophilic domain, two
EF-hands, and a leucine zipper at the C- terminus. These characters are
shared with nucleobindin (Nuc). In this paper we have further characterized
NEFA and probed its evolutionary origins. Circular dichroism (CD) spectra
of recombinant NEFA indicated a helical content of 51% and showed that the
EF-hands are capable of binding Ca2+. Experiments with recombinant NEFA and
synthesized peptides revealed that the leucine zipper cannot form a
homodimer. The leucine zipper may allow heterodimer formation of NEFA and
an unknown protein. Phylogenetic analyses suggest that this protein is
derived from a four-domain EF-hand ancestor with subsequent duplications
and fusions. The leucine zipper and putative DNA-binding domains of NEFA
have evolved secondarily from existing EF-hand sequences. These analyses
provide insights into how complex proteins may originate and trace the
precursor of NEFA to the common ancestor of eukaryotes.
相似文献
77.
We sequenced the entire control region and portions of flanking genes
(tRNA(Phe), tRNA(Glu), and ND6) in the common chaffinch (Fringilla
coelebs), blue chaffinch (F. teydea), brambling (F. montifringilla), and
greenfinch (Carduelis chloris). In these finches the control region is
similar in length (1,223-1,237 bp) and has the same flanking gene order as
in other birds, and contains a putative TAS element and the highly
conserved CSB-1 and F, D, and C boxes recognizable in most vertebrates.
Cloverleaf-like structures associated with the TAS element at the 5' end
and CSB-1 at the 3' end of the control region may be involved with the stop
and start of D-loop synthesis, respectively. The pattern of nucleotide and
substitution bias is similar to that in other vertebrates, and consequently
the finch control region can be subdivided into a central, conserved G-rich
domain (domain II) flanked by hypervariable 5'-C-rich (domain I) and
3'-AT-rich (domain III) segments. In pairwise comparisons among finch
species, the central domain has unusually low transition/transversion
ratios, which suggests that increased G + T content is a functional
constraint, possibly for DNA primase efficiency. In finches the relative
rates of evolution vary among domains according to a ratio of 4.2 (domain
III) to 2.2 (domain I) to 1 (domain II), and extensively among sites within
domains I and II. Domain I and III sequences are extremely useful in
recovering intraspecific phylogeographic splits between populations in
Africa and Europe, Madeira, and a basal lineage in Nefza, Tunisia. Domain
II sequences are highly conserved, and are therefore only useful in
conjunction with sequences from domains I and III in phylogenetic studies
of closely related species.
相似文献
78.
Soybean [Glycine max (L.) Merr.] forms a symbiosis with serogroups of Bradyrhizobium japonicum that differ in their dinitrogen fixing abilities. The objectives of this study were to identify soybean genotypes that would restrict nodulation by relatively inefficient serogroups indigenous to a large portion of the southeastern USA, and then characterize the nodulation responses of selected genotypes with specific bradyrhizobial strains under controlled conditions. From field screening trials followed by controlled single and competitive inoculations of serogroups USDA 31, 76 and 110, twelve soybean genotypes out of 382 tested were identified with varying levels of exclusion abilities. Soybean nodule occupancies and nodulation characteristics were influenced by plant genotype, environment (i.e. field or greenhouse), bradyrhizobial serogroup, and location of nodules (i.e. tap or lateral root). The cultivar Centennial sustains high seed yields even though it nodulates to a high degree with the inefficient serogroup USDA 31. In contrast, data from the released cultivars Braxton, Centennial and Coker 368 indicate that they may have been selected to exclude the inefficient serogroup USDA 76 from their tap root nodules, possibly contributing to high seed yield. 相似文献
79.
Antibody-antigen binding in organic solvents 总被引:2,自引:0,他引:2
A J Russell L J Trudel P L Skipper J D Groopman S R Tannenbaum A M Klibanov 《Biochemical and biophysical research communications》1989,158(1):80-85
We describe, for the first time, the action of antibodies in anhydrous organic solvents. It has been demonstrated that the binding of a hapten, 4-aminobiphenyl, to the immobilized monoclonal antibody 2E11 is strong and specific not only in water but also in a variety of non-aqueous media. Further, the strength of interaction between antibody and hapten has been related to the hydrophobicity of the solvent: the more hydrophobic the solvent, the weaker the protein-ligand interaction. 相似文献
80.
D Crews A Fleming E Willingham R Baldwin J K Skipper 《The Journal of experimental zoology》2001,290(6):597-606
Red-eared slider turtles are genetically bipotential for sex determination. In this species, as in many other reptiles, incubation temperature of the egg determines gonadal sex. At higher incubation temperatures females are produced and increasing temperature appears to increase estrogen production in the embryonic brain. Treatment of eggs incubating at a male-producing temperature with exogenous estrogen causes ovaries to form. At a female-biased incubation temperature, prevention of estrogen biosynthesis or administration of nonaromatizable androgens results in the development of testes. In mammals, steroidogenic factor 1 (SF-1) regulates most genes required for estrogen biosynthesis, including aromatase. In both mammals and red-eared sliders, SF-1 is differentially expressed in males and females during gonadogenesis. We have examined both SF-1 gene expression and aromatase activity in embryos incubating at different temperatures and after manipulation to change the course of gonadal development. Our findings indicate a central role for SF-1 in enacting the effect of estrogen. Estrogen treatment directly or indirectly downregulates SF-1 and, ultimately, causes development of females. The inhibition of estrogen results in upregulation of SF-1 and male hatchlings. Thus, SF-1 may lie at the center of one molecular crossroad in male versus female differentiation of the red-eared slider. 相似文献