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71.
The "Spanish" influenza pandemic of 1918-19 caused acute illness in 25-30 percent of the world's population and resulted in the death of up to an estimated 40 million people. Using fixed and frozen lung tissue of 1918 influenza victims, the complete genomic sequence of the 1918 influenza virus has been deduced. Sequence and phylogenetic analysis of the completed 1918 influenza virus genes shows them to be the most avian-like among the mammalian-adapted viruses. This finding supports the hypotheses that (1) the pandemic virus contains genes derived from avian-like influenza virus strains and that (2) the 1918 virus is the common ancestor of human and classical swine H1N1 influenza viruses. The relationship of the 1918 virus with avian influenza viruses is further supported by recent work in which the 1918 hemagglutinin (HA) protein crystal structure was resolved. Neither the 1918 hemagglutinin (HA) nor the neuraminidase (NA) genes possess mutations known to increase tissue tropicity that account for the virulence of other influenza virus strains like A/WSN/33 or the highly pathogenic avian influenza H5 or H7 viruses. Using reverse genetics approaches, influenza virus constructs containing the 1918 HA and NA on a modern human influenza virus background were lethal in mice. The complete 1918 virus was even more virulent in mice. The genotypic basis of this virulence has not yet been elucidated. The complete sequence of the non-structural (NS) gene segment of the 1918 virus was deduced and also tested for the hypothesis that enhanced virulence in 1918 could have been due to type I interferon inhibition by the NS1 protein. Results from these experiments suggest that in human cells the 1918 NS1 is a very effective interferon antagonist, but the 1918 NS1 gene does not have the amino acid change that correlates with virulence in the H5N1 virus strains identified in 1997 in Hong Kong. Sequence analysis of the 1918 pandemic influenza virus is allowing us to test hypotheses as to the origin and virulence of this strain. This information should help elucidate how pandemic influenza virus strains emerge and what genetic features contribute to virulence in humans.  相似文献   
72.
Personality traits have been posited to function as stable influences on political attitudes and behavior. Although personality traits themselves exhibit high levels of temporal stability, it is not yet known whether the effects of these traits are marked by comparable temporal consistency. To address this question, this research note examines data from Wave 13 (2003–2004), Wave 15 (2005–2006) and Wave 17 (2007–2008) of the British Household Panel Survey (BHPS). Twenty‐seven behavioral and 14 attitudinal dependent variables are studied. Consistency of effects is gauged via a series of multilevel models in which personality effects are permitted to vary by year. High levels of temporal consistency are observed for personality traits as represented by the Big Five framework.  相似文献   
73.
Preventing weight gain in adults: a pound of prevention   总被引:3,自引:0,他引:3  
This study evaluated the feasibility and effectiveness of a program for weight gain prevention in normal-weight adults. Two hundred nineteen participants were randomized to either weight gain prevention treatment or no treatment for a period of 12 months. Those in the treatment group received monthly newsletters relating to weight management, participated in a financial incentive system, and were offered an optional four-session education course in the sixth month of the program. Results demonstrated high interest in weight gain prevention among individuals who were not objectively overweight. Participation, as measured by return of postcards sent with each newsletter, was approximately 75%. Results after 1 year showed a net weight loss in the group receiving the program of 1.8 lb compared to those in the control group. Eighty-two percent of program participants maintained or lost weight, compared to 56% of the control group. It is concluded that programs for weight gain prevention are feasible in adults and may be more effective than weight loss treatment programs in addressing the problem of community-wide obesity.  相似文献   
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This longitudinal study examines the individual transition journeys of physicians as their private medical practices are acquired by a large integrated health care system. We test the proposition that transition patterns (trends in an individual's commitments to organization and profession over time) are a function of individual differences in years in profession and perceived organizational enabling characteristics (change involvement, openness to ideas, and work discretion). Three years of survey data were obtained from a panel of 48 physicians who transitioned through an organizational change process. Results challenge traditional assumptions that tenure reinforces commitment and cast doubt on the effectiveness of current medical school curricula in preparing medical graduates to practice in an administrative environment. In addition, results strongly suggest that enabling characteristics of organizational change are critical for compatibility between the organizational and professional attachments of transitioning physicians.  相似文献   
76.
    
Reaction time variability (RTV) is a ubiquitous phenomenon in Attention-Deficit/Hyperactivity Disorder (ADHD). Few studies have examined RTV in relation to functional outcomes such as social impairment in children with ADHD. In this exploratory study, we investigated whether RTV is associated with social functioning in children at risk for ADHD. Specifically, we explored the association between RTV (tau derived from correct go trials of a Stop-Signal task) and social functioning in 198 children ages 7–12 years referred for an ADHD evaluation. Social functioning measures included child and/or parent ratings of social competence, aggression, social problems, and impairment in relationships. In regression analyses that also included Oppositional Defiant Disorder symptoms and sex, higher RTV was significantly associated with lower ratings of social competence, and higher proactive/reactive aggression ratings on the child self-report measures. RTV was not significantly associated with parent report of social functioning or relationship impairment. This study provides preliminary evidence that RTV may be associated with social functioning in children at risk for ADHD. We propose that lapses of attention affecting cognitive control may also negatively impact social information processing thereby affecting social functioning. Replication is warranted and longitudinal studies are needed to investigate whether RTV predicts social dysfunction in ADHD.  相似文献   
77.
    
ABSTRACT

In 2005 India changed its pharmaceutical and innovation policy that facilitated a dramatic increase in international clinical trials involving study sites in India. This policy shift was surrounded by controversies; civil society organisations (CSOs) criticised the Indian government for promoting the commercialisation of pharmaceutical research and development. Health social movements in India fought for social justice through collective action, and engaged in normative reasoning of the benefits, burdens and equality of research. They lobbied to protect trial participants from structural violence that occurred especially in the first 5–6 years of the new policy. CSOs played a major role in the introduction of new regulations in 2013, which accelerated a decline in the number of global trials carried out in India. This activism applied interpretations of global social justice as key ideas in mobilisation, eventually helping to institutionalise stricter ethical regulation on a national level. Like government and industry, activists believed in randomised controlled trials and comparison as key methods for scientific knowledge production. However, they had significant concerns about the global hierarchies of commercial pharmaceutical research, and their impact on the rights of participants and on benefits for India overall. Pointing to ethical malpractices and lobbying for stricter ethical regulations, they aimed to ensure justice for research participants, and developed effective strategies to increase controls over the business side of clinical research.  相似文献   
78.
    
This article reports meta‐analyses intended to clarify and enhance our understanding of voice and its promotive and prohibitive forms. We find that undifferentiated constructive voice is associated with a wide range of antecedents that fit in Morrison's (2014) five categories: (a) dispositions, (b) job and organizational attitudes and perceptions, (c) emotions, beliefs, and schemas, (d) supervisor and leader behavior, and (e) contextual factors. However, relative weight analyses reveal a highly dominant variable within each category (personal initiative, felt responsibility, engagement, leader–member exchange, and positive workplace climate). We also find that undifferentiated constructive voice has a moderate zero‐order association with job performance that is nonsignificant when task performance and organizational citizenship behavior are also considered. Finally, we explore how associations vary as a function of whether voice is promotive or prohibitive. First, there are significant differences in associations with over a third of the antecedents (core self‐evaluations, felt responsibility, organizational commitment, detachment, psychological safety, ethical leadership, and leader openness). Second, although promotive voice has a positive association with job performance, the opposite is true for prohibitive voice. We conclude with suggestions to enhance our understanding of voice, especially with respect to efforts needed to clarify and distinguish promotive and prohibitive voice.  相似文献   
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Site visits provide an irreplaceable learning experience to students in both religious studies and the emerging field of interfaith studies. The conceptual core of this thesis is the claim, drawn from feminist epistemology, that an embodied pedagogy – a pedagogy which engages students not only intellectually, but as embodied beings who inhabit a space, engage in physical activities, and undergo various sensory experiences – is ultimately more enriching than a pedagogy centered exclusively in the classroom. Factors that make a site visit a successful instance of embodied pedagogy include the provision of sufficient context to students in advance for them to understand and appreciate the experience, an opportunity afterward to reflect on this experience in an intentional way, ensuring the site and the community whose space it is are treated with proper respect, and ensuring that the religious sensibilities of one's students are also similarly respected.  相似文献   
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