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1.
Transgenic celery plants were obtained following co-cultivation of petiole explants with Agrobacterlum tumefaciens containing pMON200, a cointegrate vector carrying genes for kanamycin resistance and nopaline synthase. Transformants were selected by ability of callus to grow in the presence of 50mg/l kanamycin. Transformation was confirmed either by the presence of nopaline or by Southern blots. Cytological analysis of 14 transformed plants revealed chromosomal aberrations, both in structure and number. Only 20% of the regenerated plants had the normal karyotype. Kanamycin resistance behaved as a monogenic, dominant trait, segregating in a 3:1 ratio in three families derived from plants with normal karyotypes.Abbreviations KB Kilobases - 2-4D 2,4-diphenoxyacetic acid  相似文献   
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Quiros CF  McHale N 《Genetics》1985,111(1):131-145
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Summary Chromosomes of Brassica oleracea (2n=18) were dissected from the resynthesized amphidiploid B. napus Hakuran by repeated backcrosses to B. campestris (2n=20), creating a series of monosomic alien chromosome addition line plants (2n=21). Using morphological, isozyme and restriction fragment length polymorphism markers (RFLPs), 81 putative loci were identified. Of nine possible synteny groups, seven were represented in the 25 monosomic addition plants tested. Sequences homologous to 26% of the 61 DNA clones utilized (80% were cDNA clones) were found on more than one synteny group, indicating a high level of gene duplication. Anomalous synteny associations were detected in four 2n=21 plants. One of these plants showed two markers from one B. oleracea chromosome associated with a second complete B. oleracea synteny group, suggesting translocation or recombination between non-homologous chromosomes in Hakuran or the backcross derivatives. The other three 2n=21 plants each contained two or more B. oleracea synteny groups, suggesting chromosome substitution.  相似文献   
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Experiments based on four accessions of maca (Lepdium meyenii) disclosed higher developmental rates in plants grown in neutral pH (6.6) soil when compared with those grown in acidic soil (5.3). Photoperiod response studies revealed similar growth rate for plants grown under either long day or short day condition. Plants in the field and growth chambers completed their life cycle in 11 months or less, therefore maca can be considered an annual crop. These results suggest that the range of adaptation of maca is not as narrow as previously believed, and therefore it can be successfully produced outside its natural habitat. Chromosome counts and predominance of bivalents in diakinesis and metaphase I disclosed that maca is a disomic octoploid of 2n=8x=64 chromosomes. Field and growth chamber observations and morphological uniformity of the plants within accessions indicate that maca relies mainly on self-fertilization for its reproduction.  相似文献   
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Two Apium accessions were compared with the commercial cultivar Tall Utah 52–70R (A. graveolens [L.]) for resistance to Spodoptera exigua (Hübner)(Lepidoptera: Noctuidae). Oviposition rate was not significantly different between the three genotypes. In all accessions, eggs were usually placed on the upper half of the plants. Implications of this oviposition pattern on S. exigua management in celery are discussed. The wild species A. prostratum ssp prostratum var filiform (A230) showed a significantly higher resistance to S. exigua than 52–70R. The levels of carcinogenic and mutagenic linear furanocoumarins in the commercial cultivar 52–70R (1.41 g/g in the petioles; 5.85 g/g in the leaves) and in the plant accession A. nodiflorum (5.40 g/g in the petioles; 2.99 g/g in the leaves) were far below the concentration reported to produce acute contact dermatitis (18.0 g/g). The levels of furanocoumarins in A. prostratum petioles (186.14 g/g) and leaves (326.45 g/g) were 10 and 18 times higher, respectively, than the concentration known to cause contact dermatitis. However, resistance in A. prostratum was primarily due to non-preference and the linear furanocoumarins did not induce non-preference. Therefore, the resistance shown by this plant accession does not appear to be furanocoumarin-based and may be suitable for transfer to commercial celery for use in S. exigua management.  相似文献   
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Background  

The integration of many aspects of protein/DNA structure analysis is an important requirement for software products in general area of structural bioinformatics. In fact, there are too few software packages on the internet which can be described as successful in this respect. We might say that what is still missing is publicly available, web based software for interactive analysis of the sequence/structure/function of proteins and their complexes with DNA and ligands. Some of existing software packages do have certain level of integration and do offer analysis of several structure related parameters, however not to the extent generally demanded by a user.  相似文献   
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Branca F  Li G  Goyal S  Quiros CF 《Phytochemistry》2002,59(7):717-724
In the frame of the activities carried out to exploit Sicilian local cultivars of brassicas, we focused our attention on some of the potential health compounds of various local cruciferous crops. These compounds are of interest to improve the quality of the produce with the aim to develop new cultivars capable of providing functional foods able to prevent disease. In this context, we surveyed for the presence of specific glucosinolates in local cultivars of broccoli, cauliflower, kale, and in some wild species widespread in Sicily, using as control various commercial cultivars. Glucosinolate composition varied extensively among species and crops of the same species, such as cauliflower, broccoli and kale. Cultivar variation for glucosinolate profile was also observed for some crops. For example, Sicilian cultivars of cauliflower possessing colored curds displayed a high content of glucosinolates, glucoraphanin in particular, compared to white curd commercial cultivars. Also some wild species had a high content of other glucosinolates.  相似文献   
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