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971.
Recent developments of three-dimensional printing of biomaterials (3D bioprinting) in medicine have been portrayed as demonstrating the potential to transform some medical treatments, including providing new responses to organ damage or organ failure. However, beyond the hype and before 3D bioprinted organs are ready to be transplanted into humans, several important ethical concerns and regulatory questions need to be addressed. This article starts by raising general ethical concerns associated with the use of bioprinting in medicine, then it focuses on more particular ethical issues related to experimental testing on humans, and the lack of current international regulatory directives to guide these experiments. Accordingly, this article (1) considers whether there is a limit as to what should be bioprinted in medicine; (2) examines key risks of significant harm associated with testing 3D bioprinting for humans; (3) investigates the clinical trial paradigm used to test 3D bioprinting; (4) analyses ethical questions of irreversibility, loss of treatment opportunity and replicability; (5) explores the current lack of a specific framework for the regulation and testing of 3D bioprinting treatments.  相似文献   
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Within the U.S. military, motor vehicle accidents (MVAs) are the leading cause of preventable morbidity and mortality. Prior combat exposure and anxiety symptoms are associated with risky and aggressive driving, which is responsible for over half of MVA fatalities. Therefore, interventions are needed to reduce driving anxiety and aggression in veterans in order to mitigate the public health impact of MVAs. Virtual reality exposure therapy (VRET) offers safe, controlled exposure to distressing stimuli. The current study piloted a novel virtual reality and cognitive behavioral intervention (VRET + CBT) for veterans that integrated both anxiety and anger management components. Virtual reality driving scenarios were delivered in a driving simulator and tailored for the military population. Six previously deployed veterans completed eight intervention sessions, as well as pre/post, one month follow-up and six to nine month follow-up assessments. Repeated measures ANOVAs demonstrated significant decline and large effect sizes for PTSD symptoms, driving phobia, hyperarousal in driving situations, anxiety/anger-related thoughts and behaviors, and risky driving. Hyperarousal in driving situations declined by 69%, aggressive driving declined by 29%, and risky driving declined by 21%. Treatment gains were maintained at follow-up. Recruitment, retention, immersion, simulator sickness scores, and qualitative feedback demonstrated feasibility of the intervention. Implications for future research and adaptation are discussed.  相似文献   
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Two doses diethylpropion, one dose pipradrol, one dose amobarbital and placebo were administered to 116 subjects, who rated their state on twenty variables. The variables were intercorrelated under pipradrol and pentymal. The correlation matrices were subjected to factor analysis. Four factors were found in both studies: Happiness, Alertness, Relaxation, and Flight of thoughts. There is some agreement between the two factor analyses. There were few significant effects of the drugs on factor scores, but the structure is quite unambiguous: pipradrol and diethylpropion are stimulating, and amobarbital tranquilizing.  相似文献   
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Two Pulfrich pendulums swinging in opposite phase present impossible twisting effects and also size-constancy effects.  相似文献   
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