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Steck-Bayat Kayvahn P. Henderson Stephanie Aguirre Andrea G. Smith Rachael B. Mahnert Nichole M. Gerkin Richard D. Mourad Jamal 《Journal of robotic surgery》2020,14(2):343-347
Journal of Robotic Surgery - The objectives of the study were to compare the cephalad migration of two patient positioning pads used in robotic gynecologic surgery and to determine if any... 相似文献
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Joshua C. Bunger Angela R. Melton-Celsa Ernest L. Maynard Alison D. O’Brien 《Toxins》2015,7(6):2306-2320
Shiga toxin (Stx) is an AB5 ribotoxin made by Stx-producing Escherichia coli (STEC). These organisms cause diarrhea, hemorrhagic colitis and the hemolytic uremic syndrome. STEC make two types of Stxs, Stx1 and/or Stx2. Stx2 has one prototype (a) and six subtypes (b–g), but only STEC that make Stx2a, and/or Stx2c, or Stx2d are associated with severe disease. However, Stx2c is about 10-fold less toxic than Stx2d in vivo despite only two amino acid differences in the A subunit at positions 291 and 297. We made mutations at these two sites to create intermediate toxins between Stx2c and Stx2d, and determined the 50% cytotoxic dose on Vero cells before and after heat treatment, and the 50% lethal dose in mice of the toxins. We found that serine 291 was associated with increased toxicity in vivo and that either amino acid change from that in Stx2c to that in Stx2d increased heat stability. We also assessed the secondary structure of Stx2c and Stx2d by circular dichroism (CD) spectroscopy. The CD studies suggest that Stx2c has a less-ordered secondary structure than Stx2d. We conclude that both amino acids at positions 291 and 297 in Stx2c contribute to its decreased stability and in vivo toxicity compared to Stx2d. 相似文献
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Laura D. Scherer Andrew Maynard Dana C. Dolinoy Angela Fagerlin 《Health, risk & society》2014,16(7-8):649-666
Bisphenol A is a chemical used to make certain types of plastics and is found in numerous consumer products. Because scientific studies have raised concerns about Bisphenol A’s potential impact on human health, it has been removed from some (but not all) products. What many consumers do not know, however, is that Bisphenol A is often replaced with other, less-studied chemicals whose health implications are virtually unknown. This type of situation is known as a potential ‘regrettable substitution’, because the substitute material might actually be worse than the material that it replaces. Regrettable substitutions are a common concern among policymakers, and they are a real-world manifestation of the tension that can exist between the desire to avoid risk (known possible consequences that might or might not occur) and ambiguity (second-order uncertainty), which is itself aversive. In this article, we examine how people make such trade-offs using the example of Bisphenol A. Using data from Study 1, we show that people have inconsistent preferences towards these alternatives and that choice is largely determined by irrelevant contextual factors such as the order in which the alternatives are evaluated. Using data from Study 2, we further demonstrate that when people are informed of the presence of substitute chemicals, labelling the alternative product as ‘free’ of Bisphenol A causes them to be significantly more likely to choose the alternative despite its ambiguity. We discuss the relevance of these findings for extant psychological theories as well as their implications for risk, policy and health communication. 相似文献
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Mayada Elsabbagh Rachael Bedford Atsushi Senju Tony Charman Andrew Pickles Mark H. Johnson The BASIS Team 《Social cognitive and affective neuroscience》2014,9(4):538-543
Infants’ visual scanning of social scenes is influenced by both exogenously and endogenously driven shifts of attention. We manipulate these factors by contrasting individual infants’ distribution of visual attention to the eyes relative to the mouth when viewing complex dynamic scenes with multiple communicative signals (e.g. peek-a-boo), relative to the same infant viewing simpler scenes where only single features move (moving eyes, mouth and hands). We explore the relationship between context-dependent scanning patterns and later social and communication outcomes in two groups of infants, with and without familial risk for autism. Our findings suggest that in complex scenes requiring more endogenous control of attention, increased scanning of the mouth region relative to the eyes at 7 months is associated with superior expressive language (EL) at 36 months. This relationship holds even after controlling for outcome group. In contrast, in simple scenes where only the mouth is moving, those infants, irrespective of their group membership, who direct their attention to the repetitive moving feature, i.e. the mouth, have poorer EL at 36 months. Taken together, our findings suggest that scanning of complex social scenes does not begin as strikingly different in those infants later diagnosed with autism. 相似文献
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