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1.
Aspergillus fumigatus, Aspergillus terreus, and Penicillium chrysogenum, a tellurium tolerant fungi, are able to grow on sulfur free medium amended with 0.2% (w/v) tellurite. Tellurium was incorporated into several types of low and high molecular weight proteins. The newly detected telluro-proteins contained an extraordinary high level of tellurium, as well as telluro-cysteine, telluro-cystine, telluro-methionine, and serine.  相似文献   
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Pseudomonas pseudomallei exotoxin was found to be a potent inhibitor of protein and DNA synthesis in cultured macrophages. Inhibition of DNA synthesis occurred at toxin concentrations as low as 1-2 micrograms/ml and inhibition of 3H-thymidine uptake was almost complete at concentrations of 8 micrograms/ml or more. A close correlation between cell damage and inhibition by DNA synthesis was observed. For protein synthesis, inhibition was obtained at much lower doses (0.06-2.0 micrograms/ml) of the toxin. At similar toxin concentrations, DNA synthesis was marginally affected. Further, it was shown that protein synthesis inhibition occurred almost immediately after incubation, reaching its maximal inhibitory effect of 70% after 6 hr. DNA synthesis, however, was minimally affected by a similar toxin concentration even after 10 hr of incubation. The inhibition of macromolecular synthesis in macrophages by P. pseudomallei exotoxin may be relevant to its modulatory effect on the host defense mechanism.  相似文献   
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Loranthaceae family includes hemiparasitic members which are seen invading a wide range of commercial crops. Helicanthes elasticus (Desv.) Danser is very common on mango trees. Though parasitic in nature, this mistletoe is also medicinally important as fetoprotective, against vesicular calculi and kidney infections. This study is an attempt to document macro-microscopical features of parasitic root, fruit and host-mistletoe tissue interaction in the haustorium of H. elasticus growing on mango stems. Collection, preservation, sectioning, staining and photomicrography of the root, fruit and host-mistletoe union were done as per standard methodologies of anatomical studies. Though there is resemblance to the normal roots in morphology as well as anatomy, the microscopic finding of large number of branched stone cells in the roots is interesting. The morpho-anatomical features recorded would help in understanding the infection biology of this mistletoe. The eradication during the earlier stages of its establishment from seed or from the root creeping over the surface of the host can help in controlling this parasite infection on commercially important host plants.  相似文献   
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The potential for using agricultural and industrial by-products as substrate for the production of the edible mushroom, Auricularia polytricha, was evaluated using several formulations of selected palm oil wastes mixed with sawdust and further supplemented with selected nitrogen sources. The best substrate formulations were sawdust (SD) mixed with oil palm frond (OPF; 90:10) added with 15 % spent grain (SG) and sawdust mixed with empty fruit bunch (EFB; 50:50) added with 10 % spent grain (SG) with mycelia growth rate of 8 mm/day and 7 mm/day respectively. These two substrate formulations were then subjected to different moisture content levels (65 %, 75 % and 85 %). Highest total fresh sporophore yield at 0.43 % was obtained on SD?+?OPF (90:10)?+?15 % SG at 85 % moisture content, followed closely by SD?+?EFB (50:50)?+?10 % SG with 0.40 % total yield, also at 85 % moisture content. Each of the substrate formulations at 85 % moisture content gave the highest biological efficiency (BE) at 288.9 % and 260.7 %, respectively. Both yield and biological efficiency of A. polytricha on these two formulations were almost three times higher when compared to sawdust substrate alone, thus proving the potential of these formulations to improve yield of this mushroom.  相似文献   
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One of the major flow phenomena associated with low Reynolds number flow is the formation of separation bubbles on an airfoil’s surface. NACA4415 airfoil is commonly used in wind turbines and UAV applications. The stall characteristics are gradual compared to thin airfoils. The primary criterion set for this work is the capture of laminar separation bubble. Flow is simulated for a Reynolds number of 120,000. The numerical analysis carried out shows the advantages and disadvantages of a few turbulence models. The turbulence models tested were: one equation Spallart Allmars (S-A), two equation SST K-ω, three equation Intermittency (γ) SST, k-kl-ω and finally, the four equation transition γ-Reθ SST. However, the variation in flow physics differs between these turbulence models. Procedure to establish the accuracy of the simulation, in accord with previous experimental results, has been discussed in detail.  相似文献   
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Liver, as one of the most important organs involved in lipids and glucose metabolism, is perceived as a key tissue for pharmacotherapy of insulin resistance (IRes) and type 2 diabetes. Ceramides (Cer) are biologically active lipids, which accumulation is associated with the induction of muscle IRes. We sought to determine the role of intrahepatic bioactive lipids production on insulin action in liver of insulin-resistant rats and after myriocin administration. The experiments were conducted on male Wistar rats divided into three groups: Control, fed high-fat diet (HFD), and fed HFD and treated with myriocin (HFD/Myr). Before sacrifice, the animals were infused with a [U-13C]palmitate to calculate lipid synthesis rate by means of tracer incorporation technique in particular lipid groups. Liver Cer, diacylglycerols (DAG), acyl-carnitine concentration, and isotopic enrichment were analyzed by LC/MS/MS. Proteins involved in lipid metabolism and insulin pathway were analyzed by western blot analysis. An OGTT and ITT was also performed. HFD-induced IRes and increased both the synthesis rate and the content of DAG and Cer, which was accompanied by inhibition of an insulin pathway. Interestingly, myriocin treatment reduced synthesis rate not only of Cer but also DAG and improved insulin sensitivity. We conclude that the insulin-sensitizing action of myriocin in the liver is a result of the lack of inhibitory effect of lipids on the insulin pathway, due to the reduction of their synthesis rate. This is the first study showing how the synthesis rate of individual lipid groups in liver changes after myriocin administration.  相似文献   
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Crystallographic and spectroscopic studies of a model dipeptidecontaining unusual amino acid residues establish the presence ofan intramolecular, 5-membered NH...N hydrogen bond involvingan amide NH (from 3-amino phenyl acetic acid residue) and anamide N atom from an adjacent amino acid residue in solid stateand in solution. The dipeptide also forms an infinite -sheet ribbon structure in crystals.  相似文献   
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The present study aims to evaluate the effects of feeding palm oil by-products based diets on different muscle fatty acid profiles in goats. Thirty-two Cacang × Boer goats were randomly assigned to four dietary treatments: (1) control diet (CD), (2) 80% decanter cake diet (DCD), (3) 80% palm kernel cake diet (PKCD) and (4) CD plus 5% palm oil (PO) supplemented diet (CPOD). After 100 days of feeding, four goats from each group were slaughtered and longissimus dorsi (LD), infraspinatus (IS) and biceps femoris (BF) were sampled for analysis of fatty acids. Goats fed the PKCD had higher (P<0.05) concentration of lauric acid (C12:0) than those fed the other diets in all the muscles tested. Compared to the other diets, the concentrations of palmitic acid (C16:0) and stearic acid (C18:0) were lower (P<0.05) and that of linoleic acid (C18:2 n-6) was higher (P<0.05) in the muscles from goats fed the CD. It was concluded that palm kernel cake and decanter cake can be included in the diet of goats up to 80% with more beneficial than detrimental effects on the fatty acid profile of their meat.  相似文献   
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