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1.
Tropical Animal Health and Production - Avian influenza virus (AIV) H9N2 subtype is endemic in Iran and causes substantial economic loss to the growing poultry industry within the country. In this...  相似文献   
2.
Journal of Crop Science and Biotechnology - Irrigation interruption owing to time of incidence is affecting the seed quality. The aim of this research was to determine whether the brassinolide and...  相似文献   
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A set of differentials of corn plants(Zea mays L.) containing Ht1, Ht2, Ht3 or HtN genes was used to identify races ofExserohilum turcicum in Israel. Plants were inoculated with 14 isolates ofE. turcicum collected from various regions in Israel (from Ayyelet HaShahar in the north to Sa’ad in the south). Differentials containing Ht1, Ht2, Ht3 or HtN genes were resistant to the 14 isolates tested, whereas the inbred lines without Ht genes were highly sensitive. Resistance was characterized by the formation of non-sporulating chlorotic lesions. When plants containing Ht1, Ht2 or Ht3 genes were inoculated with relatively high inoculum concentrations (over 50 conidia/drop), chlorotic lesions were associated with necrosis in the center of the lesions. Sporulation of the fungus in the necrotic parts of the lesions was significantly less than on plants without Ht genes. No necrosis was observed in plants with the HtN gene. Our results indicate that the physiological race ofE. turcicum in Israel is race 1.  相似文献   
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Fifty-one single conidial isolates ofExserohilum turcicum were collected from seven locations in Israel and three in the USA and tested for mating type and aggressiveness. Sixteen isolates mated were mating type a; 29 were mating type A; and six failed to mate with either the A or the a mating type. Isolates differed significantly in their ability to cause lesions of different sizes, and in their ability to produce conidia on the susceptible corn hybrid Jubilee. They also differed in their rate of growth on lactose casein agar. No significant difference in lesion size or conidial production was noted between mating types. Conidial production and radial growth were significantly lower for isolates with no mating capacity as compared with conidial production of defined mating types. Pseudothecia were produced after 14–16 and 21 days when mating occurred onSorghum halepense straw or barley straw, respectively. The average number of pseudothecia produced on 10 cm2 of straw was 17 and 8 forS. halepense and barley, respectively. Pseudothecia were not produced on corn straw.  相似文献   
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Veterinary Research Communications - Accurate estimation of a horse's age based on the condition of the tooth status is necessary as a scientific and artistic technique, which has not been...  相似文献   
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This experiment was conducted to evaluate the effects of different levels of sweet orange (Citrus sinensis) peel extract (SOPE) on humoral immune system responses in broiler chickens. Three hundred 1‐day broilers (Ross‐308) were randomly allocated to treatments varying in supplemental SOPE added in the drinking water. The experimental groups consisted of three treatments fed for 42 days as follows: a control treatment without feed extract, a treatment containing 1000 ppm of SOPE and a treatment containing 1250 ppm of SOPE. All treatments were isocaloric and isonitrogenous. Broilers were vaccinated with Newcastle disease virus (NDV), avian influenza (AI), infectious bursal disease (IBD) and infectious bronchitis virus (IBV) vaccines. Antibody titer response to sheep red blood cells (SRBC) was higher in the group fed 1250 ppm of SOPE (P < 0.05) as well as for immunoglobulin G (IgG) and IgM. Similarly, antibody titer responses to all vaccines were constantly elevated (P < 0.05) by SOPE enrichment in a dose‐dependent manner. Relative weights of spleen and bursa of Fabricius were unaffected by treatments. Dietary SOPE supplementation may improve the immune response and diseases resistance, indicating that it can constitute a useful additive in broiler feeding. Thus, supplying SOPE in rations may help to improve relative immune response in broiler chickens.  相似文献   
8.
Designing E1 deleted adenoviral vector by homologous recombination   总被引:2,自引:0,他引:2  
BACKGROUND: Adenoviruses are used extensively to deliver genes into mammalian cells, particularly where there is a requirement for high-level expression of transgene products in cultured cells, or for use as recombinant viral vaccines or in gene therapy. In spite of their usefulness, the construction of adenoviral vectors (AdV) is a cumbersome and lengthy process that is not readily amenable to the generation of large collection of clones. METHODS: In this project, to delete E1 gene in adenovirus, an adenoviral plasmid containing lateral sites of E1 region of adenovirus was made and recombination in the 293A cells between the homologous region of this linearized plasmid and the adenovirus genome resulted in the formation of the complete adenoviral recombinant. RESULTS: This recombination resulted in loss of E1 region and we constructed a recombinant adenovirus type 5 vector that E1 gene was deleted by homologous recombination. CONCLUSION: Homologous recombination is more easy and fast technique in the production of AdV.  相似文献   
9.
BACKGROUND: CD8 T cells are thought to play an important role in protective immunity to tuberculosis. The major histocompatibility complex class I subtype HLA-A*0201 is one of the most prevalent class I alleles, with a frequency of over 30% in most populations. HLA-A*0201 transgenic, H-2D(b)/mouse beta2-microglobulin double-knockout mice (HHD) which express human HLA-A*0201 but no mouse class 1, was shown to provide a powerful model for studying induction of HLA-A*0201-restricted immune responses in vivo. METHODS: HHD mice were immunized with plasmid DNA encoding MPB51 by using a gene gun, and IFN-gamma production from the immune spleen cells was analyzed in response to a synthetic overlapping peptide library covering the mature MPB51 sequence. catatonic T lymphocytes (CTL) activity was measured using cytotoxicity assay and the three-color flowcytometry was used to reveal IFN-gamma-producing immune spleen cells. RESULTS: Our findings were shown that only one peptide, p51-70, appeared to stimulate the immune splenocytes to produce IFN-gamma. Flow cytometric analysis with intracellular IFN-gamma and the T-cell phenotype revealed that the p51-70 peptide contains an immunodominant CD8+ T-cell epitope. Further analysis with computer-assisted algorithms permitted identification of a T-cell nona mer epitope, p54-62. Finally, we proved that the p54-62/HLA-A*0201 complex is strongly recognized by HLA class I-restricted CD8+ MPB5 1-specific CTL cells. CONCLUSION: These results suggest that vaccination with MPB51 gene elicited MPB51-specific CTL. In addition, the P54-62 epitope thus represent potential subunit component for the design of vaccines against tuberculosis.  相似文献   
10.
Newcastle disease (ND) is a highly contagious disease that affects many species of birds and causes significant economic losses to the poultry industry worldwide. Fifteen Newcastle disease virus (NDV) isolates obtained from rural chickens in northwest Ethiopia in 2011 and 2012 were characterized genotypically. The main functional region of the F gene was amplified and sequenced (260 nucleotides). Among the Ethiopian NDV isolates, 2 isolates had the virulent motif 112R-R-Q-K-R-F117 at the cleavage site of the fusion protein while 13 isolates contained the lentogenic motif 112G-G/R-Q-G-R-L117. Phylogenetic analysis based on the variable region of the F gene indicated that the two isolates exhibiting the virulent motif belonged to lineage 5 (genotype VII) subgenotype d and the remaining 13 isolates were grouped into lineage 2 (genotype II). The nucleotide sequences of lineage 5 isolates were genetically related to the Sudanese NDV isolates, suggesting potential epidemiological link of ND outbreaks between neighbouring countries. The lentogenic strains shared similarities with La Sota vaccine strain and probably originated from the vaccine strain either through direct exposure of birds to the live vaccine or to infectious La Sota-like strains circulating in rural poultry. This study provides genetic evidence on the existence of different NDV genotypes circulating in the rural poultry in Ethiopia. The virulent NDV continues to be a problem in poultry sector in Ethiopia, and their continuous circulation in rural and commercial poultry calls for improved surveillance and intensified vaccination and other control measures.  相似文献   
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