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外科医生和手术室人员经常接触手术设备产生的烟气,病人也会暴露于烟气中,特别是腹腔镜手术中产生的烟气滞留于腹腔内这一密闭空间并被吸收.这些烟气是一种与香烟烟气相似的毒性物质,然而对这种毒性物质的影响还未引起足够重视.应该采取必要措施尽可能减少手术中烟气的不良影响. 相似文献
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J Brent Richards William D Leslie Lawrence Joseph Kerry Siminoski David A Hanley Jonathan D Adachi Jacques P Brown Suzanne Morin Alexandra Papaioannou Robert G Josse Jerilynn C Prior K Shawn Davison Alan Tenenhouse David Goltzman 《Journal of bone and mineral research》2007,22(2):228-234
The impact of clinical risk factor-based absolute risk methods on the prevalence of high risk for osteoporotic fracture is unknown. We applied absolute risk methods to 6646 subjects and found that the prevalence of elderly women deemed to be at high risk increased substantially, whereas the overall prevalence was highly dependent on the threshold used to designate high risk. INTRODUCTION: Many groups have advocated using absolute risk methods that incorporate clinical risk factors to target patients for osteoporosis therapy. We examined how the application of such absolute risk classification systems influences the prevalence of those considered to be at high risk for osteoporotic fracture and compared these systems to one based solely on BMD. MATERIALS AND METHODS: Using 6646 subjects from the Canadian Multicentre Osteoporosis Study (CaMos), a prospective, randomly selected, population-based cohort, we assessed three different systems for determining prevalence of high risk for osteoporotic fracture: a BMD-based system; a simplified risk factor system incorporating age, sex, BMD, and two clinical risk factors; and a comprehensive system, incorporating age, sex, BMD, and seven clinical risk factors. The 10-year absolute risks of incident fragility fracture were compared across systems using three different high-risk thresholds. RESULTS: The prevalence of a T score < or = -2.5 was 18.8% (95% CI: 17.7-19.9%) in women and 3.9% (95% CI: 3.0-4.7%) in men. Using a 15% 10-year risk of fracture threshold, the prevalence of women at high risk increased to 46.9% (95% CI: 45.4-48.4) and 42.5% (95% CI: 41.1-43.9) when the comprehensive and simplified risk factor classification systems were used, respectively. Using a 25% 10-year absolute risk threshold, the prevalence of high risk was similar to that of the BMD-based system, whereas the 20% threshold gave intermediate rates. All thresholds analyzed resulted in an increased prevalence of older women at high risk for fracture, whereas only the 15% 10-year risk of fracture threshold resulted in an increase in the prevalence of men at high risk. CONCLUSIONS: The application of risk factor-based systems results in an increased prevalence of older women at high risk. The prevalence of individuals at high risk may increase with changes to the methods used to determine those who are eligible for therapy. These data have important implications for the pattern of care and costs of treating osteoporotic fractures. 相似文献
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A great deal is now known about the mechanisms of conditioned fear acquisition and expression. More recently, the mechanisms
of inhibition of conditioned fear have become the subject of intensive study. The major model system for the study of fear
inhibition in the laboratory is extinction, in which a previously fear conditioned organism is exposed repeatedly to the fear-eliciting
cue in the absence of any aversive event and the fear conditioned response declines. It is well established that extinction
is a form of new learning as opposed to forgetting or “unlearning” of conditioned fear, and it is hypothesized that extinction
develops when sensory pathways conveying sensory information to the amygdala come to engage GABAergic interneurons through
forms of experience-dependent plasticity such as long-term potentiation. Several laboratories currently are investigating
methods of facilitating fear extinction in animals with the hope that such treatments might ultimately prove to be useful
in facilitating exposure-based therapy for anxiety disorders in clinical populations. This review discusses the advances that
have been made in this field and presents the findings of the first major clinical study to examine the therapeutic utility
of a drug that facilitates extinction in animals. It is concluded that extinction is an excellent model system for the study
of fear inhibition and an indispensable tool for the screening of putative pharmacotherapies for clinical use. 相似文献
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PURPOSE: This articles explores cultural perceptions and values related to brain death and organ donation from both a Western and non-Western perspective. SOURCE: Anthropological literature review of the historical concept of brain death in Canada using Eastern culture as a comparison. Principal findings: Although the concept of brain death and concomitant organ donation have become widely practiced in Western nations such as Canada, from a cross-cultural point of view these concepts and practices can be deeply troubling and may hold profoundly different meaning to people new to Canada. CONCLUSIONS: Canada has a deep commitment and obligation to respect diversity as reflected in the Canadian Charter of Rights and Freedoms. Therefore, healthcare workers have an obligation to respect cultural differences. To truly respect cultural differences we must first explore our own culturally formulated belief systems and then consider how our views may interface with other cultures. Our findings call for a greater analysis of the cultural influences on the concept of brain death and organ donation as a means of building a better understanding and respect for cultural diversity. 相似文献