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Michael J. A. Simpson Donald F. Macintosh John B. Cloughley Angus E. Stuart 《Economic botany》1996,50(1):122-129
The development ofM. gale oil as an insect repellent has created a requirement for cultivation of the plant. Botanical evidence indicates thatM. gale is likely to thrive on well—aerated acid peatland and could become a valuable crop on land of low agricultural value. Plant growth would be enhanced by the prevention of grazing and could be combined with softwood forestry since the trees would benefit from soil nitrogen enrichment thanks to the symbiotic association ofM. gale andFrankia. The economics of oil production would be improved if additional compounds of value such as pharmacologically active fiavonoids could be extracted from the by-products. 相似文献
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Vassiliki Nikolopoulou Athanasios Skoutelis Konstantinos Thomopoulos Bassam Salsaa Nicholas Zoumbos 《FEMS immunology and medical microbiology》1995,10(2):115-118
Abstract There is evidence that γ/δ TCR + T cells are specialized in recognizing different antigens, but their immunologic role as a second TCR is still unclear. The aim of this study was to investigate the percentage and absolute numbers of circulating γ/δ TCR + T cells in patients with chronic viral hepatitis (CVH) and to compare with HBsAg+ , HCV healthy carriers and healthy subjects. Forty nine patients with CVH-24 with chronic active (CAH) and 25 with chronic persistent hepatitis (CPH)-, 21 HBsAg+ , 20 HCV asymptomatic carriers and 20 healthy subjects were enrolled in the study. Lymphocyte subsets were determined after incubation with monoclonal antibodies to T total (CD5) and T γ/δ cells (γ/δ-1) using immunofluorescence microscopy. An increased number of circulating γ/δ TCR + T cells was found in patients with CVH in comparison with asymptomatic carriers and normal controls: this increase was more profound in patients with CAH, compared to CPH patients. These results indicate a correlation between circulating γ/δ TCR + T cells in CVH patients and activity and chronicity of the disease. 相似文献
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Bacteriophage lambda protein phosphatase (lambdaPP) with Mn(2+) as the activating metal cofactor was studied using phosphatase inhibition kinetics and electron paramagnetic resonance (EPR) spectroscopy. Orthophosphate and the oxoanion analogues orthovanadate, tungstate, molybdate, arsenate, and sulfate were shown to inhibit the phosphomonoesterase activity of lambdaPP, albeit with inhibition constants (K(i)) that range over 5 orders of magnitude. In addition, small organic anions were tested as inhibitors. Phosphonoacetohydroxamic acid (PhAH) was found to be a strong competitive inhibitor (K(i) = 5.1 +/- 1.6 microM) whereas phosphonoacetic acid (K(i) = 380 +/- 45 microM) and acetohydroxamic acid (K(i) > 75 mM) modestly inhibited lambdaPP. Low-temperature EPR spectra of Mn(2+)-reconstituted lambdaPP in the presence of oxoanions and PhAH demonstrate that inhibitor binding decreases the spin-coupling constant, J, compared to the native enzyme. This suggests a change in the bridging interaction between Mn(2+) ions of the dimer due to protonation or replacement of a bridging ligand. Inhibitor binding also induces several spectral shifts. Hyperfine splitting characteristic of a spin-coupled (Mn(2+))(2) dimer is most prominent upon the addition of orthovanadate (K(i) = 0.70 +/- 0.20 microM) and PhAH, indicating that these inhibitors tightly interact with the (Mn(2+))(2) form of lambdaPP. These EPR and inhibition kinetic results are discussed in the context of establishing a common mechanism for the hydrolysis of phosphate esters by lambdaPP and other serine/threonine protein phosphatases. 相似文献
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Nicholas W. Gelbar Allison Shefcyk Brian Reichow 《The Yale journal of biology and medicine》2015,88(1):45-68
Background: There is a paucity of research concerning individuals with autism spectrum disorders (ASD) pursuing higher education.Method: This study sought to augment this gap in the literature by surveying individuals with ASD who are currently college students or who have previously attended college.Results: Thirty-five individuals completed an online survey. These individuals reported receiving extensive academic supports that enabled their academic success. Their reported difficulties in the social and emotional domains received less support. In addition, not all areas of campus life were supportive, as study abroad and career service offices were reported to not understand individuals with ASD.Conclusions: Overall, the results of this survey indicate the importance of self-advocacy and the need for institutions of higher education to provide comprehensive supports for individuals with ASD in the academic, social, and emotional domains in order to effectively integrate this group into the campus environment. 相似文献
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