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The eukaryotic expression plasmid of M2e-Hsp70 is a candidate M2e-based DNA vaccine. In order to evaluate the immunization potential of this construct, Specific Pathogen Free chickens were immunized either intramuscularly or orally. Mutant Salmonella typhimurium was used as carrier for oral delivery of the M2e-Hsp70 construct. M2e-specific humoral and cellular responses were tested by ELISA and Lymphocyte Proliferation Assay, respectively. Our results indicate that both humoral and cellular immune responses are conferred against M2e-Hsp70 plasmid in either of the intramuscular or oral routes of administration; however, these responses are significantly higher in intramuscular injection in contrast to oral administration. When it comes to mass vaccination of commercial chicken flocks oral administration is preferred due to the ease of application as well as its capability of eliciting mucosal, humoral and cellular immune responses; so measurements should be taken to improve the immunization potency of our orally delivered DNA vaccine.  相似文献   
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Plant growth-promoting rhizobacteria (PGPR) are soil bacteria that are able to colonize rhizosphere and to enhance plant growth by means of a wide variety of mechanisms. In the present study, Myristica yunnanensis and Stenotrophomonas chelatiphaga strains were recognized as new records in Iran flora. According to the results, these strains significantly affected plants’ zinc and phosphorous contents which could be due to the production of phytosiderophore. Siderophore-producing bacteria increased canola zinc (Zn) content as strategy-I plant, while in maize, it can be said that probably the effect of phytosiderophore produced by plant on increasing root and shoot Zn content was more than siderophore produced by bacteria. These isolates could be used as bio-input for improving the plant productivity as a substitute to chemical fertilizers and also to correct the nutrient deficiencies in canola and maize for sustainable agriculture.  相似文献   
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The present study was carried out to consideration the spider's fauna and abundance of spiders in the desert and pomegranate orchards in Tehran and Semnan provinces, during 2007. Specimens were collected from desert and pomegranate orchards by pitfall trap, shaking tree, pans, bottle and aspirator and were taken to the laboratory after labeling. A total of 1231 specimens were classified in 45 species and 36 genera belonged to 17 families. Among them 4 spider species were new for Iranian spider fauna. The families Lycosidae, Linyphiidae, Gnaphosidae and Theridiidae had height population in the study areas. Specimens were immature in the winter and spring and they were adult in the summer. The dominant species in all of study regions was Pardosa agrestis (Westring).  相似文献   
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Blood samples were obtained from 12 Iranian fat-tailed sheep during 7 weeks pre-partum, at parturition and 7 weeks post-partum. The lipids measured were cholesterol, triglyceride, total lipid, high-density lipoprotein (HDL)-cholesterol, low-density lipoprotein (LDL)-cholesterol, and very low-density lipoprotein (VLDL)-cholesterol. The concentrations of cholesterol, triglyceride, HDL-cholesterol and VLDL-cholesterol during the 7 weeks pre-partum, at parturition and the 7 weeks post-partum were significantly different (P < 0.05). One week before parturition, the concentrations of cholesterol, triglyceride, HDL-cholesterol and VLDL-cholesterol were higher (P < 0.05) than at other periods. The lowest concentrations of these parameters were observed 2-3 weeks after parturition. In this study, significant positive correlations were observed between the time of sampling (pre-partum, parturition and post-partum) and serum cholesterol (r = 0.22; P < 0.01) and HDL-cholesterol (r = 0.25; P < 0.01).  相似文献   
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Gluten strength is an important characteristic, determining the end product quality of durum wheat semolina. To identify the genetic basis of gluten strength in North Dakota durum cultivars, a doubled haploid population was developed from the cross of a weak gluten cultivar ‘Rugby’ and a strong gluten cultivar ‘Maier’. A framework linkage map consisting of 228 markers was constructed and used with phenotypic data on gluten strength (measured by sedimentation volume) to conduct single- and two-locus QTL analyses. Only one consistent QTL (QGs.ndsu-1B) contributing up to 90% of the phenotypic or 93% of the genotypic variation was detected on 1BS. No QTL × QTL or QTL × environment interactions were observed. The QGs.ndsu-1B was flanked by two DArT markers which were converted to STS markers and used along with SSR and EST-SSRs to develop a map of 1BS. QTL analysis delineated QGs.ndsu-1B in a 7.3 cM region flanked by an STS marker (STS-wPt2395) and a SSR marker (wmc85). The adapted background of this material and availability of PCR-based markers closely associated with this locus represent invaluable resources for marker-assisted introgression of gluten strength into other durum wheat varieties. A single QTL segregating in this population also makes it an ideal target for map-based cloning.  相似文献   
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In the present study, interaction between salinity (0, 40, 80, 120 mM NaCl) and vermicompost extract (VCE) on five fennel landraces (Urmia, Mashhad, Shiraz, Boushehr, Isfahan) was investigated in a factorial experiment as completely randomized design to find the best salt-tolerant landrace and potential alleviating role of VCE. Results showed that Boushehr and Isfahan were the most tolerant and sensitive landrace to salinity, respectively. Application of VCE improved germination and growth of salt-treated fennels. The amylase activity of fennels was not affected by salinity and not improved by VCE. While sodium (Na+) content of root and shoot of all salt-treated fennels increased, their potassium (K) content decreased. Under salinity stress, root K content of VCE-amended landraces was more than that of not amended ones. VCE also caused an increase in calcium (Ca) content of root of salt-treated Shiraz and Urmia landraces. In conclusion, VCE can alleviate adverse effects of salinity stress on fennel.  相似文献   
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The present study has been designed in order to verify the species composition within Anopheles maculipennis complex in North West of Iran. We determined ribosomal DNA sequences of the second internal transcribed spacer (ITS2) region from samples of Anopheles maculipennis Complex in Zanjan province. A total of 1536 specimens within the Complex were tested by Multiplex PCR, only An. maculipennis was found in this area. One clone out of four different individual mosquitoes of each field was generated with ITS2 PCR and half of them (192 samples) selected randomly for RFLPs. PCR-RFLP assay identified 2 haplotypes; haplotype I (99%) and haplotype II (1%). Twenty five sequences were generated comprising the 5.8S gene, the ITS2 and the 28S ribosomal gene. The alignment was 422 in length and percentage of GC content was 50.3% (26.07% A, 23.59% T, 26.78% C, 23.7% G). The ITS2 was 290 bp in length and two haplotypes were revealed varying by a single base (T<-->C) at site 378. An. maculipennis is the dominant species anopheline of the province. ITS2 analysis revealed evidence of a slightly interaspecific variation among populations. However, further investigations on the genetic polymorphism among An. maculipennis populations and in particular within those belonging to the continental haplotype are required to support any hypothesis on differences in behavior across the distribution range for this potential malaria vector.  相似文献   
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Forests are among the most important carbon sinks on earth. However, their complex structure and vast areas preclude accurate estimation of forest carbon stocks. Data sets from forest monitoring using advanced satellite imagery are now used in international policy agreements. Data sets enable tracking of emissions of CO2 into the atmosphere caused by deforestation and other types of land-use changes. The aim of this study is to determine the capability of SPOT-HRG Satellite data to estimate aboveground carbon stock in a district of Darabkola research and training forest, Iran. Preprocessing to eliminate or reduce geometric error and atmospheric error were performed on the images. Using cluster sampling, 165 sample plots were taken. Of 165 plots, 81 were in natural habitats, and 84 were in forest plantations. Following the collection of ground data, biomass and carbon stocks were quantified for the sample plots on a per hectare basis. Nonparametric regression models such as support vector regression were used for modeling purposes with different kernels including linear, sigmoid, polynomial, and radial basis function. The results showed that a third-degree polynomial was the best model for the entire studied areas having an root mean square error, bias and accuracy, respectively, of 38.41, 5.31, and 62.2; 42.77, 16.58, and 57.3% for the best polynomial for natural forest; and 44.71, 2.31, and 64.3% for afforestation. Overall, these results indicate that SPOT-HRG satellite data and support vector machines are useful for estimating aboveground carbon stock.  相似文献   
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