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41.
Sales MP Andrade LB Ary MB Miranda MR Teixeira FM Oliveira AS Fernandes KV Xavier-Filho J 《Comparative biochemistry and physiology. Part A, Molecular & integrative physiology》2005,142(4):422-426
Callosobruchus maculatus (Cm) and Zabrotes subfasciatus (Zs) were reared on resistant (IT81D-1045) and on susceptible (Epace 10) cowpea seeds. The emergence of adult insects, total developmental period (TDP) and excretion of trypsin inhibitor and vicilin were determined for both bruchid populations. Parameter evaluation showed that the Zs populations emerged from both seeds had no significant differences in emergence and TDP. The Cm population raised from resistant seeds had lower emergence (5.6+/-1.3%) and delayed TDP (46+/-1.25 days) than those emerged from susceptible seeds. The excretion of defense proteins showed that Zs reared in resistant seeds excreted 1.7 times more trypsin inhibitor, but this did not affect emergence or TDP. Furthermore, Cm population emerged from resistant seeds excreted 7 times higher vicilin and 0.4 times less trypsin inhibitor than that emerged from susceptible seeds. These results indicate that vicilins from resistant seeds are involved to significantly longer TDP (46 days) and also drastic reduction of insect emergence ( approximately 5%) of C. maculatus. 相似文献
42.
Jing Qin Mao Mohsin Abbas Zaidi John Thor Arnason Illimar Altosaar 《Plant Cell, Tissue and Organ Culture》2006,87(2):121-125
An in vitro regeneration system was developed in cowpea [Vigna unguiculata (L.) Walp.] Blackeye. Among several explants studied, shoot initiation response was observed from shoot apices of 3–5-day-old seedlings. The optimal medium for maximum shoot initiation comprised MS salts, B5 vitamins, 8.88 μM N
6-benzylaminopurine, 1 gl-1 casein hydrolysate, 342 μM L-glutamine, 3% sucrose, 0.3% phytagel, adjusted to pH 5.8. A shift in pH from 5.8 to 7.0 had no effect on shoot initiation and on number of shoots per explant. The highest shoot initiation frequency (77%) was obtained using this preferred medium, reaching a maximum of eight shoots per explant. For shoot elongation, 14 μM gibberellic acid was supplemented in the shoot initiation medium. Presence of indolebutyric acid in the rooting medium had no effect on root induction. The regenerated plants were fertile and developed normally. 相似文献
43.
BACKGROUND AND AIMS: Aluminium (Al) stimulates the efflux of citrate from apices of rice bean (Vigna umbellata) roots. This response is delayed at least 3 h when roots are exposed to 50 microm Al, indicating that some inducible processes leading to citrate efflux are involved. The physiological bases responsible for the delayed response were examined here. METHODS: The effects of several antagonists of anion channels and citrate carriers, and of the protein synthesis inhibitor, cycloheximide (CHM) on Al-stimulated citrate efflux and/or citrate content were examined by high-pressure liquid chromatography (HPLC) or an enzymatic method. KEY RESULTS: Both anion channel inhibitors and citrate carrier inhibitors can inhibit Al-stimulated citrate efflux, with anthracene-9-carboxylic acid (A-9-C, an anion channel inhibitor) and phenylisothiocyanate (PI, a citrate carrier inhibitor) the most effective inhibitors. A 6 h pulse of 50 microm Al induced a significant increase of citrate content in root apices and release of citrate. However, the increase in citrate content preceded the efflux. Furthermore, the release of citrate stimulated by the pulse treatment was inhibited by both A-9-C and PI, indicating the importance of the citrate carrier on the mitochondrial membrane and the anion channel on the plasma membrane for the Al-stimulated citrate efflux. CHM (20 microm) also significantly inhibited Al-stimulated citrate efflux, confirming that de novo protein synthesis is required for Al-stimulated citrate efflux. CONCLUSIONS: These results indicate that the activation of genes possibly encoding citrate transporters plays a critical role in Al-stimulated citrate efflux. 相似文献
44.
Superoxide dismutase, catalase and peroxidase activities do not confer protection against oxidative damage in salt-stressed cowpea leaves 总被引:10,自引:0,他引:10
45.
J. M. Lee D. Grant C. Eduardo Vallejos R. C. Shoemaker 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2001,103(5):765-773
Analysis of molecular linkage groups within the soybean (Glycine max L. Merr.) genome reveals many homologous regions, reflecting the ancient polyploidy of soybean. The fragmented arrangement
of the duplicated regions suggests that extensive rearrangements, as well as additional duplications, have occurred since
the initial polyploidization event. In this study we used comparisons between homoeologous regions in soybean, and the homologous
regions in the related diploids Phaseolus vulgaris and Vigna radiata, to elucidate the evolutionary history of the three legume genomes. Our results show that there is not only conservation of
large regions of the genomes but that these conserved linkage blocks are also represented twice in the soybean genome. To
gain a better understanding of the process of genome evolution in dicots, molecular comparisons have been extended to another
well-studied species, Arabidopsis thaliana. Interestingly, the conserved regions we identified in the legume species are also relatively conserved in Arabidopsis. Our
results suggest that there is conservation of blocks of DNA between species as distantly related as legumes and brassicas,
representing 90 million years of divergence. We also present evidence for an additional, presumably earlier, genome duplication
in soybean. These duplicated regions were only recognized by using Arabidopsis as a ’bridging’ species in the genome comparisons.
Received: 10 October 2000 / Accepted: 13 January 2001 相似文献
46.
Enzymic changes in response to zinc nutrition 总被引:1,自引:0,他引:1
Nalini Pandey Girish Chandra Pathak Amit Kumar Singh Chandra Prakash Sharma 《Journal of plant physiology》2002,159(10)
With a view to evaluating the suitability of Zn induced changes in enzyme activities and for assessing Zn nutrient status, black gram (Vigna mungo L. cv. IPU 94) was grown under controlled sand culture at five levels of Zn supply ranging from 0.01 to 10 μmol/L. Leaves of 60 d old plants were examined for Zn concentration and activities of fructose 1,6 biphosphate aldolase, carbonic anhydrase, total superoxide dismutase, Cu-Zn SOD, acid phosphatase and ribonuclease, which have been shown to be activated/inhibited by Zn deficiency. Sub-optimal supply of Zn decreased the activities of FBPAse, CA, total SOD and Cu-Zn SOD and increased the activities of APase and RNAse. Activities of the Zn enzymes CA and Cu-Zn SOD, are highly correlated with Zn supply, and suitable as indicators of Zn nutrient status of plants. Activation of APase and RNAse by other micronutrient deficiencies and stress conditions does not favour their use as indicators of Zn nutrient stress. 相似文献
47.
Genotypic response of cowpea Vigna unguiculata (L.) to in vitro regeneration from cotyledon explants
M. S. Brar J. M. Al-Khayri T. E. Morelock E. J. Anderson 《In vitro cellular & developmental biology. Plant》1999,35(1):8-12
Summary A plant regeneration system applicable to 17 cowpea genotypes was developed. Cotyledons were initiated on 1/3 MS medium containing
15 to 35 mg N6-benzyladenine (BA) per 1 (66.6 to 155.3 μM) for 5 to 15 d. For shoot regeneration, the explants were transferred to a medium containing 1 mg BA per 1 (4.4 μM). Within 1 wk, shoot formation was visible at the proximal end of the cotyledons. Regeneration percentages (1% to 11%) and
the numbers of shoots (4 to 12 per explant) were significantly influenced by genotype. Culture duration and BA concentration
in the initiation stage significantly affected regeneration capacity. Explants initiated on media containing 15 mg BA per
1 for 5 d resulted in the highest percentage of explants capable of regeneration. Conversely, the highest number of shoots
was obtained from explants initiated on media supplemented with 35 mg BA per 1. Whole plants were obtained on a plant growth
regulator-free medium. To our knowledge, this is the first report of plant regeneration from U.S. commercial cowpea cultivars
and breeding lines. This system is adaptable to diverse cowpea genotypes and will facilitate cowpea genetic transformation.
Published with the approval of the Director of the Arkansas Agricultural Experiment Station. 相似文献
48.
Cowpea ( Vigna unguiculata L.) leaf discs incubated in the dark in CaCl2 and benzyladenine maintained higher levels of chlorophyll and protein than controls. The CaCl2 or benzyladenine treatments reduced lipoxygenase activity, and the effect of these compounds in combination was additive. HPLC analysis of the product profile of lipoxygenase activity with arachidonic acid as a substrate showed a single peak comigrating with standard 15-hydroperoxyeicosatetraenoic acid. There appears to be a strong temporal correlation between the CaCl2 + benzyladenine delay of senescence and lipoxygenase activity. 相似文献
49.
Actin like protein, extracted and purified fromVigna radiata (mung bean) seedling, has been found to give positive enzyme-linked immunosorbent assay with mouse monoclonal antiactin antibody.
In vivo studies show that cytochalasin B at sublethal dose inhibits the chromosomal movement at metaphase stage during germination.
Fromin vitro studies it is found that the actin like protein isolated from mung bean seedling has a cytochalasin B binding property with
a Kd value 1.2 × 10−5 M. From these two specific observations it appears probable that the biological function of mung bean actin like protein
is to take part in cell division process directly or indirectly during the time of seedling development. 相似文献
50.
The presence of α-amylase inhibitor (αAI), phytohemagglutinin (PHA), and phaseolin was determined by immunochemical and biochemical methods in different members of the subtribe Phaseolinae (Phaseoleae: Fabaceae). Active αAI was present in taxa from the Phaseolus vulgaris–P. coccineus complex (P. vulgaris, P. coccineus, and P. polyanthus), as well as in P. acutifolius in accordance with previous molecular data separating these groups of species from others in the genus. All other Phaseolus species tested lacked α-amylase inhibitory activity, although some of them had immunoreactive polypeptides. αAI was found to be a polymorphic trait among wild and cultivated accessions of P. vulgaris, P. coccineus, and P. acutifolius. The presence of αAI is not exclusive of the genus Phaseolus as one of the Vigna species sampled, V. linearis, also contained α-amylase inhibitory activity. 相似文献