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排序方式: 共有340条查询结果,搜索用时 15 毫秒
241.
Designing CD4 immunoadhesins for AIDS therapy   总被引:66,自引:0,他引:66  
A newly-constructed antibody-like molecule containing the gp120-binding domain of the receptor for human immunodeficiency virus blocks HIV-1 infection of T cells and monocytes. Its long plasma half-life, other antibody-like properties, and potential to block all HIV isolates, make it a good candidate for therapeutic use.  相似文献   
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Does colour provide an input to human motion perception?   总被引:3,自引:0,他引:3  
V S Ramachandran  R L Gregory 《Nature》1978,275(5675):55-56
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244.
The weight of the stomach, small intestine and colon and the mucosal crypt cell production rate of these tissues were significantly decreased after 10 days on an isocaloric TPN diet when compared to orally fed controls. Continuous infusion of recombinant beta urogastrone, at a dose below that needed to inhibit gastric acid secretion, largely prevented this decrease in crypt cell production rate and gastrointestinal tissue weights.  相似文献   
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Zusammenfassung Der Einbau von [1-14C]-Acetat bei der Biosynthese von Xylose aus Äthanol durch die Basidiomycete B-841 beweist das Vorhandensein von drei verschiedenen Wegen des Zuckerstoffwechsels in diesem Pilz: 1. Glycolyse, 2. Transaldolase-Transketolase-Zyklus, 3. Abbau von Glucose zu Glucuronat und Pentose.  相似文献   
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The idea of the global manufacturing virtual network (GMVN) was introduced in 2000 in order to highlight an emerging as well as an alternative manufacturing system which will have strong impacts on industry and implications to management theory. During the last three years, more than thirty companies - based in the electronics, bio-pharmaceuticals, garment, and home electronics appliance industries - have been studied in the UK and China. The research project addresses the emergence of the collaborative manufacturing phenomenon at three levels - sector, system and enabling technology. This paper summarises preliminary research findings from fieldwork conducted over the last three years. It seeks to clarify the characteristics and functionality of GMVN through the case studies and to contrast it to other types of business model, such as the multinational corporations (MNC) and international strategic alliances (ISAs). It also raises some new research questions and themes for further research into GMVN.  相似文献   
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Predicting distributions of known and unknown reptile species in Madagascar   总被引:2,自引:0,他引:2  
Despite the importance of tropical biodiversity, informative species distributional data are seldom available for biogeographical study or setting conservation priorities. Modelling ecological niche distributions of species offers a potential solution; however, the utility of old locality data from museums, and of more recent remotely sensed satellite data, remains poorly explored, especially for rapidly changing tropical landscapes. Using 29 modern data sets of environmental land coverage and 621 chameleon occurrence localities from Madagascar (historical and recent), here we demonstrate a significant ability of our niche models in predicting species distribution. At 11 recently inventoried sites, highest predictive success (85.1%) was obtained for models based only on modern occurrence data (74.7% and 82.8% predictive success, respectively, for pre-1978 and all data combined). Notably, these models also identified three intersecting areas of over-prediction that recently yielded seven chameleon species new to science. We conclude that ecological niche modelling using recent locality records and readily available environmental coverage data provides informative biogeographical data for poorly known tropical landscapes, and offers innovative potential for the discovery of unknown distributional areas and unknown species.  相似文献   
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