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71.
Hari D Upadhyaya Sangam L Dwivedi Michael Baum Rajeev K Varshney Sripada M Udupa Cholenahalli LL Gowda David Hoisington Sube Singh 《BMC plant biology》2008,8(1):106
Background
Plant genetic resources (PGR) are the basic raw materials for future genetic progress and an insurance against unforeseen threats to agricultural production. An extensive characterization of PGR provides an opportunity to dissect structure, mine allelic variations, and identify diverse accessions for crop improvement. The Generation Challenge Program conceptualized the development of "composite collections" and extraction of "reference sets" from these for more efficient tapping of global crop-related genetic resources. In this study, we report the genetic structure, diversity and allelic richness in a composite collection of chickpea using SSR markers, and formation of a reference set of 300 accessions. 相似文献72.
Perepelov AV Senchenkova SN Shashkov AS Lu B Feng L Vang L Knirel' IuA 《Bioorganicheskaia khimiia》2008,34(1):121-128
The reported structures of O-specific polysaccharides from three standard strains of Shigella bacteria were corrected by modern NMR techniques. The revisions concerned the configuration of the O-glycoside linkage (S. dysenteriae type 3, structure 1), the positions of monosaccharide residue glycosylation and acetylation by pyruvic acid (S. dysenteriae type 9, structure 2), and the attachment position of the side monosaccharide chain (S. boydii type 4, structure 3) [struxture in text]. 相似文献
73.
Jakob Vang Rytter Søren Helmark Jun Chen Mateusz Jakub Lezyk Christian Solem Peter Ruhdal Jensen 《Applied microbiology and biotechnology》2014,98(6):2617-2623
The ability to modulate gene expression is an important genetic tool in systems biology and biotechnology. Here, we demonstrate that a previously published easy and fast PCR-based method for modulating gene expression in lactic acid bacteria is also applicable to Corynebacterium glutamicum. We constructed constitutive promoter libraries based on various combinations of a previously reported C. glutamicum -10 consensus sequence (gngnTA(c/t)aaTgg) and the Escherichia coli -35 consensus, either with or without an AT-rich region upstream. A promoter library based on consensus sequences frequently found in low-GC Gram-positive microorganisms was also included. The strongest promoters were found in the library with a -35 region and a C. glutamicum -10 consensus, and this library also represents the largest activity span. Using the alternative -10 consensus TATAAT, which can be found in many other prokaryotes, resulted in a weaker but still useful promoter library. The upstream AT-rich region did not appear to affect promoter strength in C. glutamicum. In addition to the constitutive promoters, a synthetic inducible promoter library, based on the E. coli lac-promoter, was constructed by randomizing the 17-bp spacer between -35 and -10 consensus sequences and the sequences surrounding these. The inducible promoter library was shown to result in β-galactosidase activities ranging from 284 to 1,665 Miller units when induced by IPTG, and the induction fold ranged from 7–59. We find that the synthetic promoter library (SPL) technology is convenient for modulating gene expression in C. glutamicum and should have many future applications, within basic research as well as for optimizing industrial production organisms. 相似文献
74.
75.
Conway LL. Powell 《Plant and Soil》1981,62(2):231-239
Summary White clover and onion plants were grown from seed in pots of sandy loam above pads of mycorrhizal inoculum soil at 0.17–1.40
g/pot (equivalent to 250–2000 kg/ha) and harvested on four occasions. In sterilized soil increasing inoculum rates increased
the onset and size of the mycorrhizal growth response of white clover. In unsterilized soil the indigenous mycorrhizal fungi
greatly stimulated growth of both clover and onion. Nevertheless, all mycorrhizal inoculum rates further stimulated shoot
growth in onion (92% increase over all harvests), while only the highest inoculum rate significantly stimulated clover growth
(52% increase). 相似文献
76.
77.
N H Vang J L Drocourt M N Thang 《Biochemical and biophysical research communications》1979,90(2):606-614
Native polynucleotide phosphorylase can be covalently bound to BrCN activated Sepharose. The Sepharose bound enzyme retains 70 % of its initial activity in polymerisation of nucleoside diphosphate. The Km of the enzyme for the polymerisation reaction in comparison to the soluble enzyme is not affected by its linkage to a solid matrix. The phosphorolysis of an hexanucleotide by the Sepharose-bound enzyme is not affected either. However, the rate of phosphorolysis of a long chain polynucleotide is dramatically altered. The Km values for poly(A) or poly(U) are increased by two orders of magnitude. The decrease of affinity for polymeric substrate is accompanied by a significant modification of the known processive mechanism characteristic of the native soluble enzyme. 相似文献
78.
Sonnhammer EL 《Genome biology》2005,6(1):301
A report on the fourth Cold Spring Harbor Laboratory/Wellcome Trust Conference on Genome Informatics, Hinxton, UK, 22-26 September 2004. 相似文献
79.
80.