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Theodore Dalrymple 《BMJ (Clinical research ed.)》2007,335(7629):1099
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The persistence of short‐term cold acclimation in Drosophila melanogaster (Diptera: Drosophilidae) 下载免费PDF全文
Elizabeth R. Everman Nicholus Ledbetter Theodore J. Morgan 《Physiological Entomology》2017,42(4):291-298
Daily and seasonal fluctuations in temperature present significant challenges for the survival of many ectothermic species that can be tempered via thermal acclimation. In the present study, we use multiple naturally derived genotypes of Drosophila melanogaster to determine the persistence of beneficial short‐term thermal acclimation on subsequent survival after cold shock. We found that the benefit of short‐term acclimation persisted for 2 h in most genotypes after a rapid cold hardening treatment. Genotype did not directly influence the persistence of short‐term acclimation benefits, indicating that environmental variation may be more important for the persistence of acclimation benefits rather than genetic capacity for acclimation. The present study extends the current understanding of the limits and importance of short‐term acclimation events, providing greater detail on the timing of the loss of short‐term acclimation benefits in a genetically variable natural population. 相似文献
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Yan-yiu Yu Chelsea Bahney Diane Hu Ralph S. Marcucio Theodore Miclau III 《Journal of visualized experiments : JoVE》2012,(62)
Assessing modes of skeletal repair is essential for developing therapies to be used clinically to treat fractures. Mechanical stability plays a large role in healing of bone injuries. In the worst-case scenario mechanical instability can lead to delayed or non-union in humans. However, motion can also stimulate the healing process. In fractures that have motion cartilage forms to stabilize the fracture bone ends, and this cartilage is gradually replaced by bone through recapitulation of the developmental process of endochondral ossification. In contrast, if a bone fracture is rigidly stabilized bone forms directly via intramembranous ossification. Clinically, both endochondral and intramembranous ossification occur simultaneously. To effectively replicate this process investigators insert a pin into the medullary canal of the fractured bone as described by Bonnarens4. This experimental method provides excellent lateral stability while allowing rotational instability to persist. However, our understanding of the mechanisms that regulate these two distinct processes can also be enhanced by experimentally isolating each of these processes. We have developed a stabilization protocol that provides rotational and lateral stabilization. In this model, intramembranous ossification is the only mode of healing that is observed, and healing parameters can be compared among different strains of genetically modified mice 5-7, after application of bioactive molecules 8,9, after altering physiological parameters of healing 10, after modifying the amount or time of stabilization 11, after distraction osteogenesis 12, after creation of a non-union 13, or after creation of a critical sized defect. Here, we illustrate how to apply the modified Ilizarov fixators for studying tibial fracture healing and distraction osteogenesis in mice. 相似文献
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The uptake of suspended human albumin microspheres containing 6-mercaptopurine-8-14C by several tumor cell lines has been followed in cell culture. In a preliminary study, HeLa, KB, and human glioblastoma cells have all been shown to phagocytize the drug-containing spheres. We suggest that if studies now in progress confirm the ability of the ingested anticancer agent to survive lysosomal digestion of the albumin spheres, phagocytosis of such spheres may prove to be a method of delivering drug to malignant cells while preventing these agents from producing toxic effects in nonphagocytic tissues. 相似文献
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Zhang Guanshi Zhang Jialing DeHoog Rachel J. Pennathur Subramaniam Anderton Christopher R. Venkatachalam Manjeri A. Alexandrov Theodore Eberlin Livia S. Sharma Kumar 《Metabolomics : Official journal of the Metabolomic Society》2020,16(1):1-12
Metabolomics - Food and dietary ingredients have significant effects on metabolism and health. To evaluate whether and how different diets affected the serum lipidomic profile of dogs. Sixteen... 相似文献