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Valérie Collot Jana Sopkova-de Oliveira Santos Pascale Schumann-Bard Nathalie Colloc'h Eric T. MacKenzie 《Journal of enzyme inhibition and medicinal chemistry》2013,28(2):195-199
The synthesis, pharmacological evaluation and modelisation of 7-methoxyindazole (7-MI) and related alkoxy-indazoles as novel inhibitors of neuronal nitric oxide synthase are presented. 7-MI remains the most active compound of this series in an in vitro enzymatic assay of neuronal nitric oxide synthase activity. Modeling studies of the interaction of 7-substituted indazole derivatives complexed with nNOS and the relationship with their respective biological activities suggest that a bulky substitution on position-7 is responsible for a steric hindrance effect which does not allow these compounds to interact with nNOS in the same way as 7-NI and 7-MI. 相似文献
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Catrina A. MacKenzie 《Journal for Nature Conservation》2012,20(2):92-100
Revenue sharing aims to balance the disadvantages people encounter living next to protected areas while fostering improved conservation behaviours. In Uganda, 20% of protected area entrance fees are shared with local governments to benefit communities adjacent to national parks. The process to distribute funds and implement projects was investigated by interviewing Uganda Wildlife Authority wardens, local government and village residents around Kibale National Park, Uganda. The perceived benefit of revenue sharing by officials and local communities was collected through interviews and a household survey, while the influence of the program on conservation objectives was assessed by measuring illegal resource extraction from the national park adjacent to study villages. It was found that the program is evolving into an effective mechanism for sharing benefits, but that better project management and increased accounting transparency could further improve the program. If the projects specifically dealt with the problem of crop raiding by park-protected animals, then villagers did benefit and lower levels of illegal activity were found inside the park. Generally household perceived benefit was low, however reduced in-park illegal activity was recorded where the village chairperson perceived higher benefit from the program, implying that the village leadership may be influencing the conservation behaviours within the community. Compared with other incentive options such as loss compensation, direct payment, and collaborative management, revenue sharing appears to be an effective and practical choice, given the limited funding available to the wildlife authority to benefit local communities while trying to improve conservation behaviours. 相似文献
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Modification of seed oil content and acyl composition in the brassicaceae by expression of a yeast sn-2 acyltransferase gene. 总被引:12,自引:1,他引:11 下载免费PDF全文
J Zou V Katavic E M Giblin D L Barton S L MacKenzie W A Keller X Hu D C Taylor 《The Plant cell》1997,9(6):909-923
A putative yeast sn-2 acyltransferase gene (SLC1-1), reportedly a variant acyltransferase that suppresses a genetic defect in sphingolipid long-chain base biosynthesis, has been expressed in a yeast SLC deletion strain. The SLC1-1 gene product was shown in vitro to encode an sn-2 acyltransferase capable of acylating sn-1 oleoyl-lysophosphatidic acid, using a range of acyl-CoA thioesters, including 18:1-, 22:1-, and 24:0-CoAs. The SLC1-1 gene was introduced into Arabidopsis and a high erucic acid-containing Brassica napus cv Hero under the control of a constitutive (tandem cauliflower mosaic virus 35S) promoter. The resulting transgenic plants showed substantial increases of 8 to 48% in seed oil content (expressed on the basis of seed dry weight) and increases in both overall proportions and amounts of very-long-chain fatty acids in seed triacylglycerols (TAGs). Furthermore, the proportion of very-long-chain fatty acids found at the sn-2 position of TAGs was increased, and homogenates prepared from developing seeds of transformed plants exhibited elevated lysophosphatidic acid acyltransferase (EC 2.3.1.51) activity. Thus, the yeast sn-2 acyltransferase has been shown to encode a protein that can exhibit lysophosphatidic acid acyltransferase activity and that can be used to change total fatty acid content and composition as well as to alter the stereospecific acyl distribution of fatty acids in seed TAGs. 相似文献
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One hundred and forty isolates of beta-hemolytic streptococcus cultured from patients with clinical pharyngitis were studied by disc diffusion for antibiotic sensitivity to lincomycin, erythromycin, cephalexin and penicillin and by agar dilution to cephalexin and penicillin. All isolates were sensitive to ≤ 0.1 μg./ml. penicillin and ≤ 1.56 μg./ml. cephalexin. The disc-diffusion test was reliable in predicting the sensitivities in vitro. One strain of group A betahemolytic streptococcus was resistant to erythromycin by disc diffusion. When compared to Lancefield grouping 18% of strains were incorrectly identified as group A by the bacitracin-disc test. Cephalexin was uniformly effective in vitro in inhibiting beta-hemolytic streptococci and the 30 μg. cephalexin disc was reliable in predicting these sensitivities. 相似文献
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