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Aquaculture experienced a significant global expansion at the end of the 20th century, becoming one of the fastest growing sectors of animal husbandry and production during that period. Chile's contribution to world expansion of salmon and trout production was notorious, given that in a short twenty five-year period it became one of the leading world producers. One prominent feature of salmon production in Chile is that the industry concentrated geographically in a limited area around Puerto Montt, in Region 10 of the country. Industry concentration cannot be exclusively explained in terms of natural advantages, and evidence is presented in favour of Venables's model (1996). A qualitative analysis of the evolution of the industry is presented to provide evidence of input-output linkages, economies of scale, competition and the progressive multiplication of inputs, applying two types of data sources: a review of the existing technical literature on the subject and in-depth interviews with 20 industry experts.  相似文献   
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We present a method for high-throughput cytological profiling by microscopy. Our system provides quantitative multidimensional measures of individual cell states over wide ranges of perturbations. We profile dose-dependent phenotypic effects of drugs in human cell culture with a titration-invariant similarity score (TISS). This method successfully categorized blinded drugs and suggested targets for drugs of uncertain mechanism. Multivariate single-cell analysis is a starting point for identifying relationships among drug effects at a systems level and a step toward phenotypic profiling at the single-cell level. Our methods will be useful for discovering the mechanism and predicting the toxicity of new drugs.  相似文献   
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Small doses of cycloheximide given at intervals (pulses) cause phase shifts of the circadian clock of Neurospora. The effects of this drug on the clock are mediated through its inhibition of protein synthesis, since two cycloheximide-resistant mutants whose 80S ribosomes are resistant to cycloheximide showed no phase shift after exposure to the durg.  相似文献   
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The only areas that are likely to have furnished the original stone for the Colossi of Memnon are near Cairo (Gebel el Ahmar), Aswan, and possibly Silsileh. Neutron activation analysis of samples from the colossi shows them to be distinctly different from samples obtained from the three known quarries near Aswan and from the quarries near Silsileh and Edfu, but very similar to samples obtained from Gebel el Ahmar. Petrographic analysis of colossi and quarry samples also provides strong evidence that the colossi came from Gebel el Ahmar. The blocks used by the engineers of Septimius Severus to reconstruct the north colossus were shown by neutron activation analysis to have originated from a deposit other than Gebel el Ahmar. The composition of these blocks conformed with samples taken from the quarries 8 and 9 km north of Edfu (the quartzite deposit closest to Thebes) and from the Aswan quarries. Petrographic analysis associated these reconstruction blocks with Edfu but not with Aswan. Neutron activation analysis of other artifacts in the area of the colossi indicates that they also came from Cairo rather than Aswan.  相似文献   
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Factor VIII activity was detected immunologically in both the serums and plasmas of 14 normal individuals and 14 patients with hemophilia A. A hemagglutination-inhibition test with rabbit antibody to highly purified (10,000-fold) factor VIII from humans was used. Serums and plasmas from eight patients with von Willebrand's disease showed little or no factor VIII activity in this test, an indication that the test may serve as a specific assay for differentiation between von Willebrand's disease and hemophilia A.  相似文献   
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Peptide antibiotics   总被引:13,自引:0,他引:13  
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