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81.
Omega‐3 (n‐3) long‐chain polyunsaturated fatty acids (LC‐PUFA) are essential components of the diet of all vertebrates. The major dietary source of n‐3 LC‐PUFA for humans has been fish and seafood but, paradoxically, farmed fish are also reliant on marine fisheries for fish meal and fish oil (FO), traditionally major ingredients of aquafeeds. Currently, the only sustainable alternatives to FO are vegetable oils, which are rich in C18 PUFA, but devoid of the eicosapentaenoic (EPA) and docosahexaenoic acids (DHA) abundant in FO. Two new n‐3 LC‐PUFA sources obtained from genetically modified (GM) Camelina sativa containing either EPA alone (ECO) or EPA and DHA (DCO) were compared to FO and wild‐type camelina oil (WCO) in juvenile sea bream. Neither ECO nor DCO had any detrimental effects on fish performance, although final weight of ECO‐fed fish (117 g) was slightly lower than that of FO‐ and DCO‐fed fish (130 and 127 g, respectively). Inclusion of the GM‐derived oils enhanced the n‐3 LC‐PUFA content in fish tissues compared to WCO, although limited biosynthesis was observed indicating accumulation of dietary fatty acids. The expression of genes involved in several lipid metabolic processes, as well as fish health and immune response, in both liver and anterior intestine were altered in fish fed the GM‐derived oils. This showed a similar pattern to that observed in WCO‐fed fish reflecting the hybrid fatty acid profile of the new oils. Overall the data indicated that the GM‐derived oils could be suitable alternatives to dietary FO in sea bream.  相似文献   
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Targeted contrast agents and ultrasound imaging are now used in combination for the assessment and tracking of biomarkers in animal models in vivo. These applications have triggered interest in the understanding and prediction of the ultrasound echoes from contrast agents attached to cells. This study describes the reflection enhancement due to microbubbles bound on a gelatin surface. The reflection enhancement was measured using ultrasound pulses at high frequency (40 MHz) and low pressure (38 kPa peak-negative pressure) allowing a linear approximation to be applied. The observed reflection coefficient increased with the number of microbubbles, until reaching saturation at 0.9 when the surface coverage fraction was 35%. A multiple scattering model assuming that the targeted microbubbles are confined within an infinitesimally thin layer appeared suitable in predicting the reflection coefficient even at very high surface densities. These results could permit the optimization of the sensitivity of high frequency ultrasound to targeted contrast agents.  相似文献   
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Rapamycin is a drug with several important clinical uses. Its complex structure means that total synthesis of this natural product and its analogues is demanding and lengthy. A more expeditious approach is to utilise biosynthesis to enable the generation of otherwise synthetically intractable analogues. In order to achieve this, rules governing biosynthetic precursor substrate preference must be established. Through determining these rules and synthesising and administering suitable substrate precursors, we demonstrate the first generation of fluorinated rapamycin analogues. Here we report the generation of six new fluororapamycins.  相似文献   
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Research on the structure of adolescent psychopathology can provide information on broad factors that underlie different forms of maladjustment in youths. Multiple studies from the literature on adult populations suggest that 2 factors, Internalizing and Externalizing, meaningfully comprise the factor structure of adult psychopathology (e.g., Krueger, 1999) and presumably represent broad vulnerability for co-occurring disorders. Though this research was partially inspired by early work with children and adolescents (e.g., Achenbach & Edelbrock, 1984), the role of substance use in these models of youth psychopathology has not been fully explored. Toward this goal, we recruited 223 youths (10–17 years of age, M = 14.2) from mental health agencies and the community. We found evidence for a 3-factor model of youth psychopathology, including Internalizing (depression, generalized anxiety), Externalizing (conduct disorder, attention deficit, oppositional defiant disorder), and Substance Use (alcohol and cannabis). The 3-factor model showed the best fit to the data relative to other factor models tested, including across subsamples of adolescents who differed on level of psychopathology (treatment vs. community samples). Implications for the structure of adolescent psychopathology, including important developmental considerations, are discussed. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
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The lymphocytes in the peripheral blood of patients with breast cancer were studied. Peripheral blood lymphocyte counts were found to be significantly lower in the short-survivors when compared with the long survivors. Lymphocyte count may be a host factor, that influences survival in breast cancer.  相似文献   
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STE20 is a newly-discovered element of the Saccharomyces cerevisiae pheromone response pathway. We have isolated a recessive ste20 mutation and have used it to map the gene to the left arm of chromosome VIII, establishing the gene order STE20-CEN8-GPA1-ARG4.  相似文献   
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