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Dromedary camels (Camelus dromedarius) play a major economic role in many countries in Africa and Asia. Although they are resistant to harsh environmental conditions, they are susceptible to a wide range of zoonotic agents. This study aimed to provide an overview on the prevalence of selected zoonotic pathogens in blood and tissues of camels in central Iran. Blood, liver, portal lymph node, and brain were collected from 100 apparently healthy camels at a slaughterhouse in Qom city to assess the presence of DNA of Brucella spp., Trypanosoma spp., Coxiella burnetii, and Bartonella spp. PCR products were sequenced bidirectionally and phylogenetic analyses were performed. Eleven percent of camels tested positive for Brucella abortus (3%) and Trypanosoma evansi (8%). Coxiella burnetii and Bartonella spp. DNA was not detected. Our data demonstrate that camels from Iran contribute to the epidemiology of some zoonotic pathogens. Performing proper control strategies, such as vaccination of camels and humans in contact with them, test-and-slaughter policy, and education of the general population is necessary for minimizing the risk of zoonotic infection.  相似文献   
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Recently, Mucor indicus was introduced as a promising ethanol producing microorganism for fermentation of lignocellulosic hydrolysates, showing a number of advantages over Saccharomyces cerevisiae. However, high nutrient requirement is the main drawback of the fungus in efficient ethanol production from lignocelluloses. In this study, application of fungal extract as a potential nutrient source replacing all required nutrients in fermentation of wheat straw by M. indicus was investigated. Wheat straw was pretreated with N-methylmorpholine-N-oxide (NMMO) at 120 °C for 1–5 h prior to enzymatic hydrolysis. Hydrolysis yield was improved at least by 6-fold for 3 h pretreated straw compared with that of untreated one. A fungal extract was produced by autolysis of M. indicus biomass, an unavoidable byproduct of fermentation. Maximum free amino nitrogen (2.04 g/L), phosphorus (1.50 g/L), and total nitrogen (4.47 g/L) as well as potassium, magnesium, and calcium in the fungal extract were obtained by autolysis of the biomass at 50 °C and pH 5.0. The fungal extract as a nutrient-rich supplement substituted yeast extract and all other required minerals in fermentation and enhanced the ethanol yield up to 92.1% of the theoretical yield. Besides, appreciate amounts of chitosan were produced as another valuable product of the autolysis.  相似文献   
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The diamondback moth (DBM), Plutella xylostella (L.) (Lepidoptera: Yponomeutidae), is the most serious pest of cauliflower fields in central Iran and its control is primarily based on pesticide sprays. Over the past years, a number of new pesticide compounds were introduced onto the market and some of them may cause adverse effects on natural populations of parasitoids associated with DBM. Excessive use of insecticides against the pest did not produce satisfactory results but has caused concerns about environmental pollution and increased pest resistance to chemicals. This research aims to study natural parasitism of pest on different cauliflower cultivars in the fields of south of Tehran. Dominant species of parasitoids include Diadegma anurum, Cotesia plutellae and Oomyzus sokolowskii. The highest parasitism rate was observed by D. anurum that was recorded on Buris cultivar (19.92?±?1.06) and White cloud cultivar (16.20?±?1.49) and the lowest parasitism rate was observed on Snow crown cultivar (3.42) and SG cultivar (5.00) during the season.  相似文献   
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Gallstone is a common biliary disorder with several risk factors. Immune responses and inflammatory cytokines are important in this disease; as a result, some cytokines can be detected in bile fluid. In this research, cytokine gene polymorphisms were studied, and their effects on gallstone formation were evaluated. On 158 gallstone patients and 254 normal subjects, by PCR- RFLP method, IL-4-C590T polymorphism and by ARMS-PCR method, IFN-γ T+874A, TNF-α-A308G, IL-6 G-174C and TGF-β T+869C variants were studied. Pathologic evaluations were done on surgical specimens. There were no significant differences in distribution of evaluated polymorphisms between patient group and normal control group (P > 0.05), except TGF-β +869T allele (P = 0.04, OR = 1.23, 95 % CI = 1–1.79) which was higher in patients with gallstone. Although the pro-inflammatory cytokines such as TNF-α and IL-6 may promote gallstone formation, in this study no significant correlation between TNF-α and IL-6 polymorphisms and gallstone formation was seen. It is taught that TGF-β may affect gallbladder cells to promote gallstone formation and higher producer TGF-β +869T allele can be a risk factor of gallstone disease, so further studies would be more elucidative.  相似文献   
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Many right-leaning politicians claim that normative Islamic perspectives on gender are at odds with the Western values and act as barriers to immigrant integration. Our interviews with 256 second-generation Somali-Canadians, however, suggest that gender-egalitarian identities are achieved – they are constructed and deployed by our participants to practice integration and express belonging in Canada. In this study, we move beyond analysis of attaining gender-egalitarian roles as a result of immigration and propose an understanding of gender as a form of Bourdieusian cultural capital that, depending on social values, functions as symbolic capital rendering individuals and groups as advantaged or disadvantaged. We, therefore, analyse modalities of “doing” gender as potential strategies of accumulating capital in furthering successful integration. Our study contributes to the emergent literature in migration studies that examines gender in relation to ethnic and national identities, and the extent to which it may impact integration experiences of second-generation Muslim immigrants.  相似文献   
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During a survey of entomopathogenic nematodes from the Mashhad region, in northeastern Iran, an entomophilic nematode was isolated using the Galleria trap method. Morphological characterization showed that this isolate belongs to the family Neodiplogastridae. Detailed morphological and morphometric characterization including SEM data fit with Pristionchus pacificus Sommer, Carta, Kim et Sternberg, 1996, representing the first record of this genus and species from Iran. Iranian specimens of P. pacificus FUM 5 are characterized by the body length (0.69–0.83 mm), the stoma (6–10 μm) bearing a dorsal tooth and a conical elongated tail (146–220 μm). Molecular analyses using 18S and ITS rDNA genes further support this identification. Measurements, illustrations, and SEM photographs of the Iranian isolate are provided and the phylogenetic position of the species is discussed.  相似文献   
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Deferrioxamine, a bacterial hydroxamic siderophore having high binding affinity for Fe(III), is used in its immobilized form, as self-assembled monolayer on Au, for accumulation and recognition of Fe(III) from the solution phase. The accumulated Fe(III) is detected via both active mode based on faradaic reduction current of Fe(III), and inactive mode based on impedimetric effect of accumulated Fe(III) against redox reaction of a suitable probe. Appropriate electrochemical techniques, square wave voltammetry and electrochemical impedance spectroscopy, are used for the transduction of analytical signals obtained by this sensor. Then, the parameters influencing the sensor response are optimized. In the best conditions, a linear response, from 1.0×10(-10) to 1.0×10(-7)M Fe(III) in logarithmic scale with a detection limit of 2.0×10(-11)M, and mean relative standard deviation of 1.7% for n=4 is observed. The results show that the sensor can be used for determination of Fe(III) in the presence of various inorganic ions and biological species. Validity of the method and applicability of the sensor are successfully tested by determination of Fe(III) in various real samples including plant tissue (corn leaves), industrial alloy (Ferrotitanium), and pharmaceutical samples (Venofer(?) ampoule, Ironorm(?) capsule, and V.M. Protein(?) powder).  相似文献   
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