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1.
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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Intraguild predation of Orius majusculus (Reuter) (Heteroptera: Anthocoridae) on Encarsia formosa (Gahan) (Hymenoptera: Aphelinidae), both natural enemies of Bemisia tabaci (Gennadius) (Homoptera: Aleyrodidae), was studied under laboratory conditions. The experiments quantified prey consumption by 5th instar nymphs and adults of O. majusculus offered unparasitised 3rd, early 4th or 4th instar B. tabaci nymphs or parasitised nymphs containing 2nd or 3rd larval instar or pupal parasitoids. In addition, prey preference of the two stages of O. majusculus for parasitised or unparasitised whitefly nymphs was studied using nine different prey combinations. Both predator stages readily preyed upon on both unparasitised and parasitised B. tabaci. In no-choice experiments, predation on 3rd instar E. formosa by adult predators was the highest, while predator nymphs preyed most on unparasitised 3rd instar B. tabaci and 2nd instar parasitoids. Predation of predator stages was lowest on 4th instar B. tabaci and E. formosa pupae. In all prey combinations, both stages of O. majusculus showed a significant preference for parasitised over unparasitised whitefly nymphs except for the combination of 5th instars of O. majusculus with early 4th instar whiteflies and E. formosa pupae. The results indicate that intraguild interactions between O. majusculus and E. formosa may have negative effects on biological control of B. tabaci.  相似文献   
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Neural responses to visual stimuli are strongest in the classical receptive field, but they are also modulated by stimuli in a much wider region. In the primary visual cortex, physiological data and models suggest that such contextual modulation is mediated by recurrent interactions between cortical areas. Outside the primary visual cortex, imaging data has shown qualitatively similar interactions. However, whether the mechanisms underlying these effects are similar in different areas has remained unclear. Here, we found that the blood oxygenation level dependent (BOLD) signal spreads over considerable cortical distances in the primary visual cortex, further than the classical receptive field. This indicates that the synaptic activity induced by a given stimulus occurs in a surprisingly extensive network. Correspondingly, we found suppressive and facilitative interactions far from the maximum retinotopic response. Next, we characterized the relationship between contextual modulation and correlation between two spatial activation patterns. Regardless of the functional area or retinotopic eccentricity, higher correlation between the center and surround response patterns was associated with stronger suppressive interaction. In individual voxels, suppressive interaction was predominant when the center and surround stimuli produced BOLD signals with the same sign. Facilitative interaction dominated in the voxels with opposite BOLD signal signs. Our data was in unison with recently published cortical decorrelation model, and was validated against alternative models, separately in different eccentricities and functional areas. Our study provides evidence that spatial interactions among neural populations involve decorrelation of macroscopic neural activation patterns, and suggests that the basic design of the cerebral cortex houses a robust decorrelation mechanism for afferent synaptic input.  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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Effect of four different cole crops (Brassica oleracea var. botrytis, Brassica oleracea var. capitata, Brassica oleracea var. italica and Brassica oleracea var. viridis) on biological parameters of the large white butterfly Pieris brassicae was evaluated at temperature 26 ± 1 °C, 60 ± 5% R. H. and a photoperiod of 16: 8 (L:D) h. The shortest larval and pupal period stages were recorded on B. oleracea var. botrytis (22.18 ± 0.20 days) and (13.32 ± 0.17 days), respectively. The life span was longest on B. oleracea var. viridis (60.43 ± 2.34 days) and shortest on B. oleracea var. botrytis (50.19 ± 0.51 days). The highest percentage of larval and pupal mortality was observed on B. oleracea var. viridis (74%), and (53%), respectively. We found that P. brassicae prefers B. oleracea var. botrytis and B. oleracea var. capitata among cole crops; it is due to the lowest percentage of larval and pupal mortality and the highest rate of life table parameters, including survival rate (lx) and life expectancy (ex), which makes them to be susceptible varieties to this pest. Contrary, a longer developmental time on B. oleracea var. viridis may be attributed to poor nutritional status and reduced survival of the cohort, resulting in high rates of mortality, which was partial resistance to pest. Knowledge of the biology and life table parameters of P. brassicae on different cole crops could be effective in detecting and monitoring the pest infestation, variety selection and crop breeding.  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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