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71.
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Osorio S Castillejo C Quesada MA Medina-Escobar N Brownsey GJ Suau R Heredia A Botella MA Valpuesta V 《The Plant journal : for cell and molecular biology》2008,54(1):43-55
In addition to the role of the cell wall as a physical barrier against pathogens, some of its constituents, such as pectin-derived oligogalacturonides (OGA), are essential components for elicitation of defence responses. To investigate how modifications of pectin alter defence responses, we expressed the fruit-specific Fragaria × ananassa pectin methyl esterase FaPE1 in the wild strawberry Fragaria vesca . Pectin from transgenic ripe fruits differed from the wild-type with regard to the degree and pattern of methyl esterification, as well as the average size of pectin polymers. Purified oligogalacturonides from the transgenic fruits showed a reduced degree of esterification compared to oligogalacturonides from wild-type fruits. This reduced esterification is necessary to elicit defence responses in strawberry. The transgenic F. vesca lines had constitutively activated pathogen defence responses, resulting in higher resistance to the necrotropic fungus Botrytis cinerea . Further studies in F. vesca and Nicotiana benthamiana leaves showed that the elicitation capacity of the oligogalacturonides is more specific than previously envisaged. 相似文献
74.
Detergents are commonly used for the extraction of hydrophobic proteins and must be removed for sensitive detection of peptides by mass spectrometry. We demonstrate that ethyl acetate is able to extract octylglycoside from a protease digest without loss of peptides or interference with the peptide mass spectral profile. Ethyl acetate extraction was also found to reduce interference by sodium dodecyl sulfate, Nonidet P-40, or Triton X-100 in the mass spectrometry analysis. 相似文献
75.
Nadina Nieves Yumaris Zambrano Raúl Tapia Mariela Cid Danilo Pina Ramiro Castillo 《Plant Cell, Tissue and Organ Culture》2003,75(3):279-282
This study shows the behaviour of sugarcane plants cv. CP-5243 derived from artificial seed compared with traditional and isolated bud methods. Artificial seed-acclimatised plants were planted in field conditions simultaneously with two-control treatments previously germinated: macropropagated plants derived from stems of three buds and axillary buds isolated from field-grown plants. Plants from artificial seed were taller and had a smaller diameter at 8 months, but these differences disappeared at 12 months. With respect to sugar analysis and yield, no differences in all parameters evaluated were found between artificial seed-derived plants and plants derived from the two other methods. 相似文献
76.
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de los Blanco Maria A. Segura-Nieto Magdalena Castillo Ramiro Nieves Nadina 《Plant Cell, Tissue and Organ Culture》1999,59(3):217-218
Storage proteins were extracted from sugarcane seeds, globular embryos (formed on embryogenic calluses and collected in early
developmental stages) and embryogenic cells. In all cases, the major percentage of storage proteins were albumins and globulins
and the lower percentage were prolamins and glutelins. Sugarcane is an interesting exception in monocots which usually have
high levels of prolamins and glutelins.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
79.
Cloning and expression of Trichoderma reesei cellobiohydrolase I in Pichia pastoris. 总被引:2,自引:0,他引:2
S Godbole S R Decker R A Nieves W S Adney T B Vinzant J O Baker S R Thomas M E Himmel 《Biotechnology progress》1999,15(5):828-833
Pichia pastoris was transformed with the Trichoderma reesei cbh1 gene, and the recombinant enzyme was purified and analyzed kinetically and by circular dichroism. The P. pastoris rCBH I was recognized by MoAb raised to T. reesei CBH I but was found in multiple molecular weight species on SDS-PAGE gels. Carbohydrate content determination and SDS-PAGE western analysis indicated that the recombinant protein was hyperglycosylated, although a species very similar in molecular weight to the T. reesei enzyme could be isolated chromatographically. The P. pastoris rCBH I also demonstrated activity toward soluble and insoluble substrates (i.e., pNPL and Sigmacell), although at a level significantly lower than the wild-type enzyme. More seriously, the yeast-expressed enzyme showed non-wild-type secondary structure by circular dichroism. We conclude that P. pastoris may not serve as an adequate host for the site-directed mutagenesis of T. reesei CBH I. 相似文献
80.
José Carlos Gonçalves Graça Diogo Maria Teresa Coelho Nieves Vidal Sara Amâncio 《In vitro cellular & developmental biology. Plant》2008,44(5):412-418
Endogenous levels of indole-3-acetic acid (IAA), indole-3-acetylaspartic acid (IAAsp) and indole-3-butyric acid (IBA) were
measured during the first 8 d of in vitro rooting of rootstock from the chestnut ‘M3’ hybrid by high performance liquid chromatography (HPLC). Rooting was induced
either by dipping the basal ends of the shoots into a 4.92-mM IBA solution for 1 min or by sub-culturing the shoots on solid
rooting medium supplemented with 14.8-μM IBA for 5 d. For root development, the induced shoots were transferred to auxin-free
solid medium. Auxins were measured in the apical and basal parts of the shoots by means of HPLC. Endogenous levels of IAA
and IAAsp were found to be greater in IBA-treated shoots than in control shoots. In extracts of the basal parts of the shoots,
the concentration of free IAA showed a significant peak 2 d after either root inductive method and a subsequent gradual decrease
for the remainder of the time course. The concentration of IAAsp peaked at day 6 in extracts of the basal parts of shoots
induced with 14.8-μM IBA for 5 d, whereas shoots induced by dipping showed an initial increase until day 2 and then remained
stable. In extracts from basal shoot portions induced by dipping, IBA concentration showed a transient peak at day 1 and a
plateau between day 2 and 4, in contrast to the profile of shoots induced on auxin-containing medium, which showed a significant
reduction between 4 and 6 d after transferred to auxin-free medium. All quantified auxins remained at a relatively low level,
virtually constant, in extracts from apical shoot portions, as well as in extracts from control non-rooting shoots. In conclusion,
the natural auxin IAA is the signal responsible for root induction, although it is driven by exogenous IBA independently of
the adding conditions. 相似文献