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排序方式: 共有424条查询结果,搜索用时 15 毫秒
1.
The Marek's disease virus (MDV) glycoprotein B (gB) precursor, gp100, is proteolytically cleaved into two disulfide-linked subunits, gp60 and gp49. In the gB homologs of most other herpesviruses, a tetrapeptide, Arg-Xaa-Arg-Arg, is immediately upstream from the predicted cleavage site. We have investigated the specificity of the proteolytic cleavage in gplOO by introducing mutations within its predicted cleavage site (Arg-Leu-Arg-Arg) and expressed these mutants in recombinant fowlpox virus (FPV). The results show that all three Arg residues at the predicted cleavage site play an important role in the specific proteolytic cleavage of gp100. Furthermore, we demonstrated that the cleavage of gplOO is not necessary for transport of gB to the cell surface. 相似文献
2.
Aliasghar Bahari Sakineh Azami Ali Goudarztalejerdi Saeid Karimi Saber Esmaeili Bruno B. Chomel Alireza Sazmand 《The Yale journal of biology and medicine》2021,94(2):249
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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Saied Ghadimi Ali Asghar Ebrahimi Valmoozi Mehrdad Pourayoubi Keyvan Asad Samani 《Journal of enzyme inhibition and medicinal chemistry》2013,28(4):556-561
Phosphoramido acid esters (CH3)2NP(O)X(p-OC6H4-CH3) (containing P-Cl (1), P-O (2), P-F (3), P-CN (5), and P-N (4,6) bonds, X for 2, 4 and 6 is OCH3, (C2H5)2N and morpholin) have been synthesized to investigate the structure-activity study of AChE enzyme inhibition, through the parameters logP, δ31P and IC50. After their characterization by 31P, 31P{1H}, 13C, 1H NMR, IR and mass spectroscopy, the parameters logP and δ31P (31P chemical shift in NMR) were used to evaluated the lipophilicity and electronical properties. The ability of compounds to inhibit human AChE was predicted by PASS software (version 1.193), and experimentally evaluated by a modified Ellman's assay. 相似文献
5.
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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Gholamhosein Hasanshahi Habib Abbasipour Fatemeh Jahan Alireza Askarianzadeh Jaber Karimi Ali Hossein Rahimi 《Archives Of Phytopathology And Plant Protection》2013,46(4):456-463
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
8.
Abbas Azadmehr Keyvan Alizadeh Oghyanous Reza Hajiaghaee Zahra Amirghofran Mohammad Azadbakht 《Cellular and molecular neurobiology》2013,33(8):1135-1141
In this study, the neuroprotective effect of Scrophularia striata Boiss (Scrophulariaceae) extract, a plant growing in northeastern of Iran, against oxidative stress-induced neurocytotoxicity in PC12 was evaluated. The PC12 cell line pretreated with different concentrations (10, 50, 100, and 200 μg/ml) of the extract and then treated with H2O2 to induce oxidative stress and neurotoxicity. Survival of the cells, reactive oxygen species (ROS) generation, and apoptosis were measured using MTT assay, fluorescent probe 2′,7′-dichlorofluorescein diacetate, and annexin V/propidium iodide, respectively. Moreover, the 2,2-diphenyl-1-picryl-hydrazyl (DPPH) was used to evaluate the antioxidant capacity of the plant extract. Phytochemical assay by thin layer chromatography showed that the main components, including phenolic compounds, phenyl propanoids and flavonoids, were presented in the S. striata extract. The extract in concentrations of 50–200 μg/ml protected PC12 cells from H2O2-induced toxicity. The survival of the cells at concentration of 200 μg/ml was 64 % compared to that of H2O2 alone-treated cells (48 %) (p < 0.001). The extract also dose-dependently reduced intracellular ROS production (p < 0.001). Moreover, the extract showed antioxidative effects and decreased apoptotic cells. Collectively, these findings indicated the ability of S. striata to decrease ROS generation and cell apoptosis and also suggest the presence of the neuroprotective agents in this plant. 相似文献
9.
Padideh Ebadi Saeed Daneshmandi Abbas Ghasemi Mohammad Hossein Karimi 《Molecular biology reports》2013,40(11):6255-6260
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
10.
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