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This study determined the full-length sequence of CYP2E1, one of six cytochrome P450 genes previously examined in camel tissues by western blotting and semi-quantitative PCR. The Camelus dromedarius CYP2E1 has an open reading frame of 1,473 bp, and the cDNA encodes a protein of 490 amino acid residues with a molecular weight of 54.8 kDa. The deduced amino acid sequence showed the highest identity with Bos taurus (88%), Sus scrofa (87%), and Homo sapiens (83%). In a phylogenetic analysis, the C. dromedarius CYP2E1 isoform was located beside cattle and pigs. The deduced amino acid sequence of camel CYP2E1 showed the conserved proline-rich amino terminus and the heme-binding signature localized near the carboxy terminus of the protein.  相似文献   
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We have developed an integrase-defective lentiviral (LV) vector in combination with a gene-targeting approach for gene therapy of β-thalassemia. The β-globin gene-targeting construct has two homologous stems including sequence upstream and downstream of the β-globin gene, a β-globin gene positioned between hygromycin and neomycin resistant genes and a herpes simplex virus type 1 thymidine kinase (HSVtk) suicide gene. Utilization of integrase-defective LV as a vector for the β-globin gene increased the number of selected clones relative to non-viral methods. This method represents an important step toward the ultimate goal of a clinical gene therapy for β-thalassemia.  相似文献   
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Physiological changes induced by chromium stress in plants: an overview   总被引:1,自引:0,他引:1  
This article presents an overview of the mechanism of chromium (Cr) stress in plants. Toxic effects of Cr on plant growth and development depend primarily on its valence state. Cr(VI) is highly toxic and mobile whereas Cr(III) is less toxic. Cr-induced oxidative stress involves induction of lipid peroxidation in plants that cause severe damage to cell membranes which includes degradation of photosynthetic pigments causing deterioration in growth. The potential of plants with the adequacy to accumulate or to stabilize Cr compounds for bioremediation of Cr contamination has gained engrossment in recent years.  相似文献   
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Methicillin-ResistantStaphylococcus aureus (MSRA) has become a frequent cause of serious infections. Extended hospitalization and antibiotic therapy have been identified as additional risk factors for MRSA carrier and infection. The aim of this study was to determine the incidence of MRSA infections in the hospitals affiliated to Hamedan University of Medical Sciences. SeventyS. aureus clinical strains were isolated from patients from June 2005 to June 2006 and examined by PCR and conventional microbiological tests. Then, the antibiotic susceptibility to methicillin/oxacillin and other antibiotics were performed by Disc Diffusion Agar (DDA). The results of this study showed that methicillin resistance gene was detected in 35 (50%) and 22 (31.4%) cases by PCR and DDA, respectively. The results of antibiotic susceptibility assays also showed there were high resistance MRSA strains to penicilin (100%), cloxacillin (91.4%), tetracycline (74.2%), cotrimoxazole (68.5%), erythromycin (68.5%) and less resistance to rifampin (11.4). Two MRSA also had decreased susceptibility to vancomycin. But the strains of Methicillin-SensitiveS. aureus (MSSA) showed high sensitivity to all antibiotics profiles except to penicillin (complete resistance). As a conclusion, the resistance to methicillin/oxacillin ofS. aureus in Hamedan hospitals has reached to 50% and they show multidrug resistance.  相似文献   
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The hypoxic niche of tumor leads to a tremendous increase in the extracellular adenosine concentration through alteration of adenosine metabolism in the tumor microenvironment (TME). This consequently affects cancer progression, local immune responses, and apoptosis of tumor cells. Regulatory effect of adenosine on apoptosis in TME depends on the cancer cell type, pharmacological characteristics of adenosine receptor subtypes, and the adenosine concentration in the tumor niche. Exploiting specific pharmacological adenosine receptor agonist and antagonist inducing apoptosis in cancer cells can be considered as a proper procedure to control cancer progression. This review summarizes the regulatory role of adenosine in cancer cell apoptosis for a better understanding, and hence better management of the disease.  相似文献   
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Microbial hydroxylation of progesterone occurred in the culture of Acremonium strictum PTCC 5282 to produce two hydroxylated pregnene-like steroids. The metabolites were purified and characterized using spectroscopic methods and identified as 15alpha-hydroxyprogesterone and 15alpha-hydroxydeoxycorticosterone.  相似文献   
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Five cyanobacterial species (Phormidium sp., Nostoc sp., Anabaena sp. Aphanothece conferta, and Synechocystis aquatilis) isolated from the Suez Canal coast at the city of Ismailia (Egypt) were tested for biodegradation of four hydrocarbon (HC) compounds: two aliphatic compounds (n‐octadecane and pristine) and two aromatic compounds (phenanthrene and dibenzothiophene). High degradation efficiencies for the two aliphatic compounds were measured for A. conferta (64% for n‐octadecane and 78% for pristine) and S. aquatilis (85% for n‐octadecane and 90% for pristane). However, the other biodegradation percentages ranged between weak and moderate percentages.  相似文献   
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