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51.
The M2e peptide of the H5N1 A/Chicken/Kurgan/05/2005 avian influenza virus was successfully synthesized in transgenic tobacco plants. The amino-terminal segment of the M2 protein, comprised of 22, 30, or 43 amino acids, including the M2e peptide (M122, M130, and M143 variants, respectively), was translationally fused with the N-terminus of β-glucuronidase in the pBI121 plant expression vector. The nucleotide sequence of the target fragment was synthesized by ligation from synthetic oligonucleotides; its codon composition was adapted for expression in plants. Tobacco plants were successfully transformed with the obtained vectors (pBIM122, pBIM130, and pBIM143, respectively). In the plants transformed with pBIM143, the Ml43-β-glucuronidase fusion protein was not produced, probably due to the presence of the M2 protein transmembrane domain (25–43 aa of M2) in this construct. In the pBIM122- and pBIMl30-transformed plants, the target M2e peptide was expressed as a component of the Ml22-β-glucuronidase and M130-β-glucuronidase fusion proteins, respectively, as was detected by Western blot analysis. These proteins were detected as bands of the expected size without apparent degradation. As a result, the M2e peptide of the H5N1 avian influenza virus was successfully synthesized for the first time in nuclear-transformed transgenic plants. The results obtained in this study will be used for developing a transgenic plant-based edible antiinfluenza vaccine.  相似文献   
52.
Culex (Culex) pipiens (Diptera: Culicidae) has two recognized biotypes, pipiens and molestus, which differ in physiology and behaviour; this difference may influence vectorial capacity for West Nile virus (WNV). Our goal was first to determine the presence of Cx. pipiens populations in 31 locations in Portugal and to subsequently analyse their host‐feeding preferences and habitat determinants. Molecular identification of Cx. pipiens forms and their hybrids was performed in 97 females; bloodmeal sources were identified in 59 engorged specimens. Overall, 61.9% of specimens were identified as Cx. pipiens f. pipiens, 20.6% as Cx. pipiens f. molestus, and 17.5% as hybrid forms. Culex pipiens f. pipiens fed preferentially on birds, and Cx. pipiens f. molestus on humans. Hybrid forms fed mostly on birds, but human bloodmeals were common. With reference to habitat, Cx. pipiens f. pipiens and hybrid forms were positively correlated with peri‐urban habitats. Our results confirm the sympatric presence of different Cx. pipiens biotypes in 14 of the 31 locations studied. Peri‐urban areas were a common habitat of all biotypes and may represent zones of hybridization. The feeding preferences and sympatric distribution of the Cx. pipiens biotypes observed in Portugal favour the epizootic circulation of WNV and the occurrence of disease outbreaks of WNV.  相似文献   
53.
The effects of modifying boron (B) and calcium (Ca2+) concentrations on the establishment and development of rhizobial symbiosis in Pisum sativum plants grown under salt stress were investigated. Salinity almost completely inhibited the nodulation of pea plants by Rhizobium leguminosarum bv. viciae 3841. This effect was prevented by addition of Ca2+ during plant growth. The capacity of root exudates derived from salt‐treated plants to induce Rhizobium nod genes was not significantly decreased. However, bacterial adsorption to roots was highly inhibited in plants grown with 75 mM NaCl. Moreover, R. leguminosarum 3841 did not grow in minimal media containing such salt concentration. High Ca2+ levels enhanced both rhizobial growth and adsorption to roots, and increased nodule number in the presence of high salt. Nevertheless, the nodules developed were not functional unless the B concentration was also increased. Because B has a strong effect on infection and cell invasion, these processes were investigated by fluorescence microscopy in pea nodules harbouring a R. leguminosarum strain that expresses green fluorescent protein. Salt‐stressed plants had empty nodules and only those treated with high B and high Ca2+ developed infection threads and exhibited enhanced cell and tissue invasion by Rhizobium. Overall, the results indicate that Ca2+ promotes nodulation and B nodule development leading to an increase of salt tolerance of nodulated legumes.  相似文献   
54.
Polymorphisms in genes of circadian system family seem to be of most importance for understanding of mechanisms underlying self-assessed individual variation in morning–evening preference. A review of earlier reported positive findings indicated that, at least, four polymorphisms in period circadian clock 3 (PER3) showed significant association with, at least, one of sub-constructs of a morningness–eveningness scale. However, similar to other candidate gene studies, these studies suffer from increased likelihood of false positive findings. We tried to replicate some of the most recently published positive results on associations of sub-traits of morningness–eveningness with two PER3 non-synonymous single nucleotide polymorphisms. DNA from buccal swabs was collected from healthy residents of three Russian cities, Moscow (N = 149) and Novosibirsk and Stavropol (N = 248). The tested hypotheses were formulated in accord with the earlier reported positive findings: the rare alleles might be linked to a higher score on (i) morning earliness–lateness scale (rs2640909, Moscow data-set) and (ii) both morning and evening earliness–lateness scales (rs228729, Novosibirsk and Stavropol datasets). The results provided support for the former hypothesis. These and earlier reported results highlighted several critical issues that remained to be addressed in future independent replications of positive findings on potential genetic markers for morning and evening earliness–lateness.  相似文献   
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56.
Subcutaneous larvae of Hypoderma spp. (Diptera: Oestridae) were detected in the dorsal region in 10 roe deer, Capreolus capreolus (Artiodactyla: Cervidae), hunted in central Spain between January and March 2016. All larvae were found in the inner side of the hide during the skinning of the animals. The study of the morphological features of eight larvae of different stages collected from two animals allowed the identification of Hypoderma actaeon Brauer. The small size (4–5 mm) of some of the first instars suggests that the internal lifecycle of H. actaeon may be exclusively subcutaneous. This is the first confirmation of H. actaeon in roe deer; however, further studies to assess the spread of the parasite and to follow the evolution of this myiasis in roe deer are needed.  相似文献   
57.
Valenzuela-Ríos, 7.1. 1994 10 15 The Lower Devonian conodont Pedavis pesavis and the pesavis Zone.
Records from Europe and Western North America suggest that a diversification of Pedavis faunas took place around the base of what has been called the pesavis Zone. This level is reviewed in comparison to sequences in Western North America and Spain. Hitherto, two different taxa, Pedavis pesavis S.S. and Pedavis striatus (= Icriodus pesavis of Klapper 1969) have been used indiscriminately in defining the base of the pesavis Zone. This revision points out that the chronostratigraphic problems derived from an unknown phylogenetic history of both P. striatus and P. pesavis remain still unsolved, and thii fact challenges the continued use of either taxon as a zonal index for dating and correlating purposes. To improve this situation a new biostratigraphic unit above the delta Zone is proposed, the pandora beta - gilberti unit. This unit is unambiguosly defined, and thus it now enables accurate correlation on a global-scale basis above the delta Zone. Conodonts, biostratigraphy, Lower Devonian, Pyrenees, Nevada .  相似文献   
58.
Hoarding food is an important strategy of rodents in desert environments characterized by unpredictable and poor food resource availability. In the Monte Desert, Prosopis produces abundant food, unevenly in time and space, in the form of pods and seeds. Sigmodontine rodents (Graomys griseoflavus, Akodon molinae, Eligmodontia typus and Calomys musculinus) use Prosopis propagules extensively, and they could be predators or dispersers depending on how they handle and where they leave the propagules. The objectives of this study were: (1) to know what rodent species transported propagules; (2) to evaluate what hoarding pattern was used by species that transport propagules (larder and scatterhoarding); and (3) to analyse in which condition were propagules left by the rodent species, both at the food source and in caches. Our results showed that all four species transported propagules, with G. griseoflavus and E. typus being the species that carried more seeds. Our study supported the evidence that food caching is common among species and that many species both larderhoard and scatterhoard food. Graomys griseoflavus and A. molinae, the largest species, larderhoarded more than did the smaller E. typus. These results uphold the hypothesis that larger species will show greater propensity to larderhoard than smaller species. Considering the interaction between seed‐hoarding patterns and plants, E. typus was the species that could most improve germination because it scatterhoarded propagules and left seeds out of pods. In contrast, G. griseoflavus could have a negative impact on plant populations because this was the species that predated more seeds and larderhoarded a high percentage of them. The smallest C. musculinus was the species that transported propagules least, and left them as seeds inside pods or pod segments mainly at the food source, which makes seeds more vulnerable to predation.  相似文献   
59.
Biochemistry (Moscow) - Potato virus Y (PVY) is one of the most common and harmful plant viruses. Translation of viral RNA starts with the interaction between the plant cap-binding translation...  相似文献   
60.
Plant cold shock domain proteins (CSDP) participate in maintenance of plant stress tolerance and in regulating their development. In the present paper we show that two out of three extremophyte plant Eutrema salsugineum proteins EsCSDP1-3, namely EsCSDP1 and EsCSDP3, possess high DNA-melting activity. DNA-melting activity of proteins was evaluated using molecular beacon assay in two ways: by measuring Tm parameter (the temperature at which half of the DNA beacon molecules is fully melted) and the beacon fluorescence at 4 °C. As the ratio protein/beacon was increased, a decrease in Tm was observed. Besides DNA-melting activity of full proteins, activity was measured for three isolated cold shock domains EsCSD1-3, C-terminal domain of EsCSDP1 (EsZnF1), as well as a mixture of EsCSD1 and EsZnF1. The Tm reduction efficiency of proteins formed the following sequence: EsCSDP3≈EsCSDP1>(EsCSD1+EsZnF1)>EsZnF1>EsCSDP2. Only full proteins EsCSDP3 and EsCSDP1 demonstrated DNA-melting activity at 4 °C. The presented experimental data indicate that i: interaction of EsCSDP1-3 with beacon single-stranded region is obligatory for efficient melting; ii: cold shock domain and C-terminal domain with zinc finger motifs should be present in one protein molecule to have high melting activity.  相似文献   
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