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The GroES antigen provokes a strong immune response in human beings with tuberculosis or leprosy. We cloned and sequenced the Mycobacterium avium and Mycobacterium paratuberculosis GroES genes. M. avium and M. paratuberculosis have identical GroES sequences which differ from other mycobacterial species. This supports the current formal designation of M. paratuberculosis as M. avium subsp. paratuberculosis. Immunodominant epitopes from Mycobacterium tuberculosis GroES are conserved in M. avium, but some Mycobacterium leprae epitopes are distinct. GroES is unlikely to be specific as a serologic or skin test reagent, but may be an appropriate component of a broad mycobacterial vaccine.  相似文献   
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Summary The use of imazethapyr as a sprout suppressant in potatoes has been investigated. Novel radionuclide techniques were developed to establish the patterns of uptake and movement of imazethapyr in potatoes. Protocols for tissue analysis were established to homogenise potato tuber tissue samples, enabling radiolabel recovery by liquid scintillation counting to approach 100%. The movement of imazethapyr was also examined in the presence of an acidic formulation of thiabendazole which caused increased uptake. The movement of imazethapyr within the tuber was also influenced by pH and ion trapping.  相似文献   
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The scientific identification of the key components of sexual reproduction - eggs and sperm - took place during an amazing decade of discovery in the 1660s and 1670s. The names of many of the people involved are now forgotten, and yet their work, and the difficulties they faced and the conflicts they endured, resonate strongly to the present day. Despite this period of innovation, the respective roles of egg and sperm remained unclear for another 170 years. Why did this take so long? And what did people think before these discoveries? By tracing the contours of this major milestone in human knowledge, we can also gain insight into our current knowledge, and the boundaries we may be unwittingly trapped by.  相似文献   
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This article reviews the literature on the complex and variable nature of the dog–human dyad and describes the influence of terms such as “dominance” on attitudes that humans have toward dogs. It highlights a legacy of tension between ethology and psychology and notes that some practitioners have skills with dogs that elude the best learning theorists. Despite the widespread appeal of being able to communicate with dogs as dogs do with one another, attempting to apply the intraspecific dog ethogram to human–dog and dog–human interactions may have limited scope. The balance of learning theory and ethology on our interactions with dogs is sometimes elusive but should spur the scientific community to examine skills deployed by the most effective humane practitioners. This process will demystify the so-called whispering techniques and permit discourse on the reasons some training and handling techniques are more effective, relevant, and humane than others. This article explores the mismatch between the use of nonverbal communication of 2 species and offers a framework for future studies in this domain. Technologies emerging from equitation science may help to disclose confusing interventions through the collar and lead and thus define effective and humane use of negative reinforcement. The case for a validated intraspecific and interspecific canid ethogram is also made.  相似文献   
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This paper analyses the structural change in small‐island economies—sometimes labeled offshore financial centers (OFCs)—that have seen wealth‐generating activities through offshore financial services decrease in value since 2008. At the same time, OFCs have come under increasing scrutiny from supranational organizations such Organization for Economic Co‐operation and Development and European Union for perceived unfair tax practices and money laundering activities. Some OFCs have proactively adjusted to this sea change by broadening the economic base through development of new offshore business activities such as e‐gaming, film industry, and niche manufacturing. Most have increased co‐operation with onshore regulatory bodies to promote service and product legitimacy. Econometric analysis explores the assertion that OFCs that do not have a political link to the onshore may be exposed to greater capital inflows volatility than OFCs that have such a link. Case study analysis using the theoretical lens of evolutionary economic geography illustrates that a small OFC is creating spatialities of economic novelty by adapting economic development strategies deployed during the successful development of the center prior to the recent recession. Our findings reveal the importance of political links to the onshore to reduce capital inflow volatility and the importance of local public–private interaction to legitimize post‐recession development.  相似文献   
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