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Aníbal Pauchard Ann Milbau Ann Albihn Jake Alexander Treena Burgess Curtis Daehler Göran Englund Franz Essl Birgitta Evengård Gregory B. Greenwood Sylvia Haider Jonathan Lenoir Keith McDougall Erin Muths Martin A. Nuñez Johan Olofsson Loic Pellissier Wolfgang Rabitsch Lisa J. Rew Mark Robertson Nathan Sanders Christoph Kueffer 《Biological invasions》2016,18(2):345-353
Cold environments at high elevation and high latitude are often viewed as resistant to biological invasions. However, climate warming, land use change and associated increased connectivity all increase the risk of biological invasions in these environments. Here we present a summary of the key discussions of the workshop ‘Biosecurity in Mountains and Northern Ecosystems: Current Status and Future Challenges’ (Flen, Sweden, 1–3 June 2015). The aims of the workshop were to (1) increase awareness about the growing importance of species expansion—both non-native and native—at high elevation and high latitude with climate change, (2) review existing knowledge about invasion risks in these areas, and (3) encourage more research on how species will move and interact in cold environments, the consequences for biodiversity, and animal and human health and wellbeing. The diversity of potential and actual invaders reported at the workshop and the likely interactions between them create major challenges for managers of cold environments. However, since these cold environments have experienced fewer invasions when compared with many warmer, more populated environments, prevention has a real chance of success, especially if it is coupled with prioritisation schemes for targeting invaders likely to have greatest impact. Communication and co-operation between cold environment regions will facilitate rapid response, and maximise the use of limited research and management resources. 相似文献
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T Giannina B G Steinetz C L Rassaert E A McDougall A Meli 《Proceedings of the Society for Experimental Biology and Medicine. Society for Experimental Biology and Medicine (New York, N.Y.)》1969,131(3):781-789
An orally active progestagen, 17 alpha-ethynyl-19-nor-testosterone-17 beta-acetate-3-cyclopeotyl enol-ether (ENTACP) was found to be a potent antiestrual and contraceptive agent in rats. It was evaluated with respect to: 1) progestational activity, 2) pregnancy maintenance, 3) androgenic activity, 4) masculinization of female fetuses, 5) uterotropic activity, 6) effect on adrenal and adrenocortical function, 7) effect on organs and body weight, 8) effect on pregnancy, 9) storage in body fat. ENTACP was twice as effective in producing secretory changes of the endometrium as its parent compound. Pregnancy was not maintained; however, after 22 days, resorption sites were still visable. ENTACP was about 1.5 times as effective as its parent compound in stimulating accessory organs during daily administration. A daily dose of .9 mg orally produced masculinization of the female fetuses, but did not interfere with parturition. Resorption of fetuses occurred more frequently in rats treated with ENTACP than with other compounds tested. ENTACP behaved like an estrogen in stimulating uterine growth. Adrenal weight was significantly increased with ENTACP administration and it reduced the capacity of the adrenal cortical tissue to respond to ACTH. Body weight gain suffered in direct proportion to dose administration. Adrenals, hypophysis, and thyroid increased when expressed in mg/100 gm body weight, and thymus decreased. The oral daily dose of .5 mg/animal from day 1-11 after mating did not prevent pregnancy. At the 5 mg/animal dose nidation was interfered with. Oral administration was not followed by storage of steroid material in body fat. 相似文献
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The enzymic synthesis of benzylpenicillin from 6-aminopenicillanic acid in the presence of poly (ethylene glycol) has been studied. With equimolar initial concentrations (20 mM) of 6-aminopenicillanic acid and phenylacetic acid a 60% conversion to benzylpenicillin can be achieved at 10°C and pH 5.2 in the presence of 45% (w/v) poly(ethylene glycol). Under these conditions the lactam ring of the benzylpenicillin and 6-aminopenicillanic acid and the enzyme, penicillin acylase (penicillin amidase, penicillin amidohydrolase, EC 3.5.1.11), were more stable than in the absence of the polyol. 相似文献
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