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1.
The aim of this study was to identify the group of highly polymorphic microsatellite markers for identification of promising sour cherries. From among 30 tested microsatellite (SSR) markers, 19 were selected to profile genetic variation in sour cherries due to high polymorphisms. Results indicated a high level of polymorphism of the accessions based on these markers. Totally 148 alleles were generated at 19 SSR loci which 122 alleles were polymorphic. The number of total alleles per locus ranged from 2 to 15 with an average of 7.78 and polymorphism percentage varied from 50 to 100% with an average of 78.76%. Also, PIC varied from 0.47 to 0.89 with an average of 0.79 and heterozygosity ranged from 0.35 to 0.55 with a mean of 0.45. According to these results, these markers specially PMS3, PS12A02, PceGA34, BPPCT021, EMPA004, EMPA018, and Pchgms3 produced good and various levels of amplifications and showed high heterozygosity levels. By the way, the genetic similarity showed a high diversity among the sour cherries. Cluster analysis separated improved cultivars from promising sour cherries, and the PCoA supported the cluster analysis results. Since the studied sour cherries were superior to the improved cultivars and were separated from them in most groups, these sour cherries can be considered as distinct genotypes for further evaluations in the framework of breeding programs and new cultivar identification in cherries. Results also confirmed that the set of microsatellite markers employed in this study demonstrated usefulness of microsatellite markers for the identification of sour cherry genotypes.  相似文献   
2.
Subgenus Cerasus species are useful genetic resources for cherry breeding programs. A total of 17 morphological traits together with 19 random amplified polymorphic DNA (RAPD) primers were used to study 39 accessions including 34 wild Cerasus subgenus genotypes belonging to Prunus avium L., P. cerasus L., P. mahaleb L., P. microcarpa Boiss., P. incana Pall., and P. brachypetala Boiss. species, along with an unknown wild Cerasus sample, two advanced cherry cultivars (‘Lambert’ and ‘Bulgar’), and two rootstocks (‘Colt’ and ‘Gisela 6’). Genotypes were separated into different groups according to their species and collection sites using cluster analysis performed by Ward’s clustering method based on morphological data. Nineteen RAPD primers from 60 screened produced 304 polymorphic reproducible bands (98.15% polymorphism). According to the similarity matrix, the lowest similarity was obtained between P. avium and P. microcarpa samples. A dendrogram was prepared by the unweighted pair-group method with arithmetic average (UPGMA), and the accessions were separated according to their species and geographic origin. In both morphological and molecular results, the advanced cultivars and rootstocks were separated from wild genotypes, and the unknown genotype was grouped with P. mahaleb accessions. Grouping by morphological characteristics was compared with the results of RAPD analysis, with no significant correlations between morphological and molecular data being found. This is the first report of molecular (RAPD) genetic diversity study in wild Cerasus subgenus genotypes from Iran, and the results demonstrate the high potential of RAPD analysis for discrimination of Cerasus subgenus genotypes.  相似文献   
3.
Verotoxin (VT) or shiga toxin (Stx) produced by enterohemorrhagic Escherichia coli (EHEC) and Shigella dysenteriae is AB5 holotoxin with potent protein synthesis inhibitor. VT can induce both apoptosis and necrosis depending on the cell type, it has been shown that VT-induced apoptosis and cytotoxicity are distinct processes, and the A subunit can be necessary for apoptosis. In other words, the precise role of each subunit in apoptosis signaling has yet to be established. In this study, induction of apoptosis has been examined by using both recombinant A and B subunits, and recombinant Stx (rStx) with different doses in HeLa and Vero cells. For this purpose, the polymyxin B extract of constructs expressing A, B and AB5 recombinant proteins was used. Therefore, amounts greater than normally reported were used to induce desire effects on cell lines. The apoptotic effect of A and B subunits appear at higher doses than that of rStx. The highest apoptotic effect was observed for rStx at low concentration, compared to A and B subunits. A or B subunits separately cannot induce the signaling pathway stimulated by holotoxin though A subunit, does induce laddering pattern similar to holotoxin. We concluded that both subunits are important in complete death signaling pathway. Since different concentration of A and B subunits and rStx was required in different assay, therefore, it could be emphasized that cell death or even apoptosis caused by either of the subunits or holotoxin depends on sensitivity or specificity of the assay and cell types used.  相似文献   
4.
Targeted drug delivery is an attractive field in cancer studies. In this study, a novel fusion protein consisting of Shiga toxin A subunit and NGR peptide has been constructed. The cytotoxic Shiga toxin A subunit has the ability to kill cancer cells while NGR is a well-known peptide that targets the whole molecule to cancer cells. Two forms of this novel fusion protein, one without linker (A-NGR) and one with linker (A-GGGGS-NGR) were studied. 3D structure prediction of the two forms carried out by I-TASSER and their validation and analysis were performed by ProSA web and RAMPAGE. Results showed that A-NGR is a better model than the one with linker. A-NGR was constructed by PCR method and cloned in pBAD/gIII A vector. Then, it was successfully expressed in Escherichia coli by induction with arabinose and subsequently purified by affinity chromatography under denaturing condition. Ultimately, the cytotoxic effect of the purified protein was evaluated on U937 cancer cells and MRC-5 normal cells by MTT assay. Conclusively, the fusion protein was successfully cloned and expressed and evaluated for its cytotoxic effects. The IC50 value of A-NGR fusion protein for U937 cell was about 26.86 µg/ml while no cytotoxic effect was observed on MRC-5 cells. Therefore, considering the promising cytotoxic effects of the fusion protein, further in vitro evaluations of this fusion protein on different cell lines are underway.  相似文献   
5.
International Journal of Peptide Research and Therapeutics - Immunoinformatics or vaccine informatics focuses on applying computational approaches to advance vaccine research and development...  相似文献   
6.
Multiple sclerosis (MS) is the most common autoimmune disease characterized by multifocal areas of inflammatory demyelination within the central nervous system. Cytomegalovirus (CMV) has a complex pathobiology and in most cases is simply asymptomatic. There is some recent controversy over the role of CMV in the pathology of MS. The aim of this study was to evaluate active CMV infection and its effect on the humoral immunity in patients with MS. Serum, plasma, peripheral blood mononuclear cells (PBMCs), saliva and urine collected from MS patients (n=78) and healthy subjects (n=123) were screened for the presence of anti-CMV antibodies and CMV-DNA by nephelometric and PCR methods. Concentrations of total antibodies in MS subtypes were measured using both nephelometric and enzyme linked fluorescent assay (ELFA) techniques. The results extend the observation of an increased frequency of CMV-DNA in patients, in contrast with controls (p<0.001). Furthermore, systemic CMV infections were found in 25.5% of patients and only 3.2% of controls (p<0.001). There was significant difference in the titers of anti-CMV IgG and total IgE in patient and controls (P<0.001). These results support the hypothesis that CMV may contribute to MS thought to establish systemic infection process and induce immune response.  相似文献   
7.
Among the progressive neurodegenerative disorders, Parkinson's disease (PD) is the second most common. Different factors have critical role in pathophysiology of PD such as apoptosis pathways, inflammatory cytokines, oxidative stress, and neurotransmitters and its receptors abnormalities. Acupuncture and electroacupuncture were considered as nondrug therapies for PD. Although numerous studies has been conducted for assessing the mechanism underlying electroacupuncture and acupuncture, various principal aspects of these treatment procedures remain not well-known. There have also been few investigations on the molecular mechanism of acupuncture and electroacupuncture therapy effects in PD. This review evaluates the effects of electroacupuncture and acupuncture on the molecular mechanism in PD.  相似文献   
8.
Escherichia coli clones expressing recombinant shiga toxin (Stx1) and its derivatives Stx1-A and Stx1-B subunits were established to release the proteins into periplasmic space. The expression was examined by SDS-PAGE to visualize the subunits. The secreted assembled subunits were extracted with polymyxin B and assessed for biological activity. The results showed that the presence of N-terminus leader sequence of the gene is essential for assembly of the subunits to yield biologically active holotoxin (AB5). The absence of the leader sequence did not affect the expression of the subunits but did disrupt the holotoxin assembly.  相似文献   
9.
As Iran is one of the main origins of Prunus germplasm. In this study, ISSR markers were used for genetic diversity evaluation of 39 accessions of subgenus Cerasus belonging to six species i.e. Prunus avium L., Prunus cerasus L., Prunus mahaleb L., Prunus incana Pall., Prunus microcarpa Boiss., and Prunus brachypetala Boiss.. With 12 ISSR primers, 151 polymorphic bands were detected with polymorphism ratio range of 81.8%–100%. The lowest similarity (0.04) was found between P. avium and P. microcarpa genotypes and the mean of similarity between all genotypes was 0.28. Cluster analysis separated improved cultivars from wild accessions. Improved cherry cultivars and rootstocks were placed closer to the P. avium than the other species. The principal coordinate analysis (PCoA) supported the cluster analysis results. The wild accessions were separated according to their species and collection sites. ISSR markers are useful techniques for genetic diversity evaluation in Prunus subgenus Cerasus.  相似文献   
10.
The presence of the genes for Escherichia coli adherence factor (EAF), attaching and effacing lesion (eae) and bundle-forming pili (bfp) in 72 strains identified as enteropathogenic E. coli (EPEC) by slide agglutination was evaluated using hybridization and PCR. The adherence property of these strains was assayed using 3h HeLa cells adherence assay. The results obtained indicated that virulence-associated genes were present in 65% of the strains but only ten (13.9%) isolates were positive for all the three markers (typical EPEC), 37 (51.4%) isolates carried either one or two of these determinants (atypical EPEC) and the remaining 25 (34.7%) were negative for all these genes. In vitro adherence assay showed that 44 (61.1%) strains adhered to HeLa cells with a defined pattern, 13 (18.1%) isolates adhered loosely with no definite pattern and the remaining 15 (20.8%) were non-adherent. Analysis of the results showed a statistically significant association between the presence of the virulence-related genes with adherence of the strains with a defined pattern (P相似文献   
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