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61.
Background
Pathway-targeted or low-density arrays are used more and more frequently in biomedical research, particularly those arrays that are based on quantitative real-time PCR. Typical QPCR arrays contain 96-1024 primer pairs or probes, and they bring with it the promise of being able to reliably measure differences in target levels without the need to establish absolute standard curves for each and every target. To achieve reliable quantification all primer pairs or array probes must perform with the same efficiency. 相似文献62.
Natasha Maurmann Carina M. B. De Carvalho Andréia Loviane Silva Arthur G. Fett-Neto Gilsane L. von Poser Sandra B. Rech 《In vitro cellular & developmental biology. Plant》2006,42(1):50-53
Summary
Valeriana glechomifolia is an endemic species of southern Brazil, capable of accumulating, in all of its organs, the terpene derivatives known as
valepotriates, the presumed sedative components of the roots of pharmaceutically used species of Valeriana. In vitro cultures of the plant were established and the accumulation of acevaltrate, didrovaltrate, and valtrate in callus, cell suspension,
and untransformed root cultures was studied. Leaves of in natura plants and roots of micropropagated plantlets were used as the explants for callus induction and root culture establishment,
respectively, on Gamborg B5 basal medium supplemented with 2,4-dichlorophenoxyacetic acid (2,4-D) alone or with kinetin (KIN).
Culture growth and secondary metabolite yields were enhanced with 2,4-D (4.52μM) and KIN (0.93μM). Maximum valepotriate contents, quantified by HPLC, of acevaltrate (ACE) 2.6mg g−1 DW, valtrate (VAL) 10.2mgg−1 DW, and didrovaltrate (DID) 2.9mg g−1 DW were observed in root cultures after 7–8wk of culture. 相似文献
63.
Valeriana glechomifolia is a plant species endemic to southern Brazil that accumulates valepotriates, which are terpene derivatives, in all of its organs. Valepotriates are the presumed sedative generic components of the pharmaceutically used species of Valeriana. The influence of various concentrations of the auxins indole-3-acetic acid, indole-3-butyric acid and -naphthaleneacetic acid on the growth of micropropagated V. glechomifolia was investigated under conditions of transient and continuous exposure. Changes in the development of roots and shoots as well as the production of the valepotriates acevaltrate, valtrate and didrovaltrate (analyzed by high-performance liquid chromatography) were evaluated. The best performance in valepotriate production, growth and survival under ex vitro conditions following plant acclimatization was achieved in the continuous presence of 5.71 M IAA. When cultured in medium containing IAA plants produced stable levels of valepotriates throughout the entire cultivation period.Abbreviations ACE
Acevaltrate
- IAA
Indole-3-acetic acid
- IBA
Indole-3-butyric acid
- DW
Dry weight
- DID
Didrovaltrate
- NAA
-Naphthaleneacetic acid
- PVP
Polyvinylpyrrolidone
- VAL
Valtrate 相似文献
64.
P. T. Lynch J. Jones H. Zhang E. L. Rech P. S. Eyles S. L. Kothari N. W. Blackhall E. C. Cocking M. R. Davey 《Physiologia plantarum》1992,85(2):362-366
Transgenic rice plants have been regenerated from kanamycin-resistant callus of Oryza sativa (cv. Taipei 309) derived from protoplasts electroporated with pCaMVNEO carrying the neomycin phosphotransferase II ( nptII ) gene. Of 6 randomly selected plants, all contained the nptll gene, but only 2 plants expressed NPTII activity. The transgenic plants were significantly shorter, produced fewer tillers, took longer to flower and had reduced fertility compared to non-transformed protoplastderived plants. Fifty-six seeds collected from one transgenic plant expressing NPTII activity germinated on medium containing kanamycin sulphate to give 16 green, first seed generation (R1 ) plants. The latter could be divided into 3 groups: (i) Plants which set seed, had normal floret morphology and produced a total of 76 seeds; (ii) Plants which flowered, but which failed to set seed; (iii) Plants which failed to flower, were shorter and had significantly fewer tillers than plants of groups (i) and (ii). The nptII gene was present in all transgenic R1 plants, but only 8 plants expressed the gene. Phenotypic characteristics, observed in transgenic R1 plants were also seen in the transforned R2 plants. These included reduced stature, a longer vegetative phase and reduced fertility compared to non-transformed plants. 相似文献
65.
The C-protein tetramer binds 230 to 240 nucleotides of pre-mRNA and nucleates the assembly of 40S heterogeneous nuclear ribonucleoprotein particles. 总被引:7,自引:2,他引:5
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66.
Comparative analysis of the zeta-crystallin/quinone reductase gene in guinea pig and mouse 总被引:1,自引:0,他引:1
Gonzalez P; Hernandez-Calzadilla C; Rao PV; Rodriguez IR; Zigler JS Jr; Borras T 《Molecular biology and evolution》1994,11(2):305-315
zeta-Crystallin is a novel nicotinamide adenine dinucleotide
phosphate:quinone reductase, present at enzymatic levels in various tissues
of different species, which is highly expressed in the lens of some
hystricomorph rodents and camelids. We report here the complementary DNA
(cDNA) cloning of zeta-crystallin from liver libraries in guinea pig (Cavia
porcellus), where zeta-crystallin is highly expressed in the lens, and in
the laboratory mouse (Mus musculus), where expression in the lens occurs
only at enzymatic levels. A 5' untranslated sequence different from the one
previously reported for the guinea pig lens cDNA was found in these clones.
We also report the isolation of genomic clones including the complete
guinea pig zeta-crystallin gene and the 5' region of this gene in mouse.
These results show the presence of two promoters in the guinea pig
zeta-crystallin gene, one responsible for expression at enzymatic levels
and the other responsible for the high expression in the lens. The guinea
pig lens promoter is not present in the mouse gene. This is the first
example in which the recruitment of an enzyme as a lens crystallin can be
explained by the acquisition of an alternative lens- specific promoter.
相似文献
67.
Mayla Daiane Correa Molinari Renata Fuganti-Pagliarini Daniel de Amorim Barbosa Silvana Regina Rockenbach Marin Daniel Rockenbach Marin Elíbio Leopoldo Rech Liliane Marcia Mertz-Henning Alexandre Lima Nepomuceno 《Genetics and molecular biology》2022,45(1)
Soybean is a key crop in many countries, being used from human food to the animal industry due to its nutritional properties. Financially, the grain chain moves large sums of money into the economy of producing countries. However, like other agricultural commodities around the world, it can have its final yield seriously compromised by abiotic environmental stressors, like drought. As flowers imply in pods and in grains inside it to minimize damages caused by water restriction, researchers have focused on understanding flowering-process related genes and their interactions. Here a review dedicated to the soybean flowering process and gene network involved in it is presented, describing gene interactions and how genes act in this complex mechanism, also ruled by environmental triggers such as day-light and circadian cycle. The objective was to gather information and insights on the soybean flowering process, aiming to provide knowledge useful to assist in the development of drought-tolerant soybean lines, minimizing losses due to delays or anticipation of flowering and, consequently, restraining financial and productivity losses. 相似文献
68.
High frequency gene transfer by microprojectile bombardment of intact conidia from the entomopathogenic fungus Paecilomyces fumosoroseus 总被引:1,自引:0,他引:1
69.
High frequency gene conversion among benomyl resistant transformants in the entomopathogenic fungus Metarhizium anisopliae 总被引:4,自引:0,他引:4
Maurício Reis Bogo Marilene Henning Vainstein francisco JoséLima Aragão Elíbio Rech Augusto Schrank 《FEMS microbiology letters》1996,142(1):123-127
Abstract Three different methods, (i) PEG, (ii) electroporation and (iii) biolistic, were employed to transform Metarhizium anisopliae using benomyl resistance as a selectable marker. Transformation frequencies and mitotic stability varied for each method, from 0.8 to 6.9 transformants μg−1 of DNA and 46%, respectively, by the PEG method; 1.3 to 1.8 transformants μg−1 of DNA and 67% by electroporation; and 32 to 201 transformants μg−1 of DNA and 90% by biolistic. We demonstrate by PCR that 60% of the transformants were generated by gene conversion. 相似文献
70.
Low copy-number bacterial replicons occupy specific locations in their host cells. Production of a GFP-Lac repressor hybrid protein in cells carrying F or P1 plasmids tagged with a lac operator array reveals that in smaller (younger) cells these plasmids are seen mainly as a single fluorescent focus at mid-cell, whereas larger cells tend to have two foci, one at each quarter-cell position. Duplication of the central focus is presumed to represent active partition of plasmid copies. We report here our investigation by time-lapse microscopy of the subsequent movement of these copies to the quarter positions. Following duplication of the central focus, the new foci migrated rapidly and directly to their quarter-cell destinations, where they remained until the next cell cycle. The speed of movement was about five times faster than poleward migration of oriC and 50 times faster than cell elongation. Aberrant positioning of mini-F lacking its sopC centromere demonstrated the requirement for the partition system in this localization process. From the measured number of F plasmid copies per cell it appears that each migrating focus contains two or more plasmid molecules. The molecular basis of this clustering, and evidence for phasing of the partition event in the cell cycle, are discussed. 相似文献