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Space exploration--surgical insights and future perspectives   总被引:1,自引:0,他引:1  
NASA's space exploration initiative envisions a return to the moon by 2020, the construction of inhabited lunar bases and manned missions to Mars. Such an ambitious program harbours increased risks, both logistical and physical (particularly that of trauma) within the context of a microgravity environment. This paper also discusses the cellular response to microgravity and the potential scientific and technological benefits of Space exploration.  相似文献   
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This ecological study investigated whether the relationship between social disadvantage and hospitalization for psychoses changed during a time of social and economic stressors in an urban setting. Hospital separation rates were compared in the census years 1991 and 1996. Rates were 66% higher in the lowest income areas compared to the richest areas; but this relationship did not change over time. Instead, rates for psychoses increased by about 15% over time. These findings may be due to an increase in the need, a change in the level of resources or in coding practices. As hospital separation data are collected systematically in many countries, they can be used to monitor the progress of mental health reform. Variations in an area may signify that resources need to be redistributed more equitably and/or at a faster pace.  相似文献   
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Agha‐Hosseini F, Jahani M‐A, Jahani M, Mirzaii‐Dizgah I, Ali‐Moghaddam K. In vitro isolation of stem cells derived from human dental pulp.
Clin Transplant 2009: DOI: 10.1111/j.1399‐0012.2009.01137.x.
© 2009 John Wiley & Sons A/S. Abstract: Stem cells are characterized by the ability to differentiate and to self‐renew. Stem cells derived from human dental pulp have been shown to differentiate into osteoblasts serving as a potential source of autologous bone produced in vitro. The purpose of the present study was to isolate mesenchymal stem cells from dental pulp. Dental pulp was gently extracted from 27 intact human permanent third molars of patients aged 18–25. Cow horn forceps were used to isolate intact dental pulp in sterilized condition. The pulps were cultured in a medium containing Dulbecco’s modified Eagle’s medium‐low glucose (DMEM)‐LG and Amphotericin 1%. The cells were subsequently expanded by passages, two passages were performed before they were stored in liquid nitrogen for further examination. DMEM + fetal bovine serum (FBS) 10% L‐Glutamin 0.1% + Trypsin 2.5% + ethylene diamine tetraacetic acid (EDTA) were used for passage. Light microscope and flow cytometry were used to study the cells. The isolated dental pulp cells expressed mesenchymal stem cell markers. The cells were negative for CD34 and CD31 and CD45 but were positive for CD13, CD44, CD90, CD166, and CD105. These results indicate that dental pulp can be use as a source of stem cells that we can isolate and culture.  相似文献   
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The Fogg Behavior Model (FBM) is a new framework which posits that behavior happens when three factors – motivation, ability, and a prompt – occur in the same moment. The FBM categorizes people into four groups based on motivation and ability and posits that those with high motivation and high ability will adopt a behavior when prompted. Two rounds of panel survey data from 617 married men in urban Pakistan were used to test this hypothesis. Multilevel mixed-effects logistic regression was used for the analysis. The results show the relationships between ability, motivation, the prompt and condom use to be as hypothesized by the FBM. After adjustment for a range of variables including fertility desires, education, and household wealth, the odds of condom use among men with high motivation and high ability were 34 times higher than the odds of condom use among men with low motivation and low ability. Moreover, the association between the prompt and condom use operated through increased motivation and ability. The FBM has potential for use in the design and evaluation of behavior change interventions in developing countries.  相似文献   
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