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Coronary artery bypass grafting with cardiopulmonary bypass (CPB) is known to be associated with a systemic inflammatory response, which contributes to the development of postoperative complications including multiple organ dysfunction. Off-pump coronary surgery has been shown to attenuate the inflammatory injury compared to the conventional approach, thereby reducing the incidence of postoperative cardiopulmonary, renal, or neurological dysfunction. It is believed that off-pump experience may greatly impact on improving the outcome of coronary surgery in certain high-risk patients. Moreover, a better understanding of the underlying mechanism would also help to improve our current CPB management. Accumulating evidence to date indicates that a balance between pro- and antiinflammatory responses is crucial in limiting the extent of such systemic inflammatory injury following surgical myocardial revascularization.  相似文献   
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This article provides an overview of the evidence on the ways racism can affect the disproportionate rates of cardiovascular disease (CVD) in African Americans. It describes the significant health disparities in CVD for blacks and whites and suggests that racial disparities should be understood within the context of persistent inequities in societal institutions and relations. Evidence and potential pathways for exploring effects of 3 levels of racism on cardiovascular health risk factors and outcomes are reviewed. First, institutional racism can lead to limited opportunities for socioeconomic mobility, differential access to goods and resources, and poor living conditions that can adversely affect cardiovascular health. Second, perceived/personally mediated racism acts as a stressor and can induce psychophysiological reactions that negatively affect cardiovascular health. Third, in race-conscious societies, such as the United States, the negative self-evaluations of accepting negative cultural stereotypes as true (internalized racism) can have deleterious effects on cardiovascular health. Few population-based studies have examined the relationship between racism and CVD. The findings, though suggestive of a positive association, are neither consistent nor clear. The research agenda of the Jackson Heart Study in addressing the role of racism in CVD is presented.  相似文献   
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Beginning medical students spend numerous hours every week attending basic science lectures and taking notes. Medical faculty often wonder whether they should give students pre-printed instructors' notes before lectures. Proponents of this strategy argue that provided notes enhance learning by facilitating the accurate transmission of information, while opponents counter that provided notes inhibit students' cognitive processing or even discourage students from attending lectures. Little if any research has directly addressed medical students' note-taking or the value of providing instructors' notes. The educational literature does suggest that taking lecture notes enhances university students' learning. University students perform best on post-lecture testing if they review a combination of provided notes and their own personal notes, particularly if the provided notes follow a 'skeletal' format that encourages active note-taking.  相似文献   
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Telomerase is not an oncogene   总被引:20,自引:0,他引:20  
Harley CB 《Oncogene》2002,21(4):494-502
In the decade since the telomere hypothesis of cellular aging was proposed, the two essential genes for human telomerase were cloned and characterized, allowing experimental proof of the causal relationships between telomere loss and replicative senescence, and telomerase activation and immortalization. These relationships were established using a variety of cultured human cell types from both normal and tumor tissues, and were largely confirmed in the telomerase knockout mouse. Taken together, the data provide strong support for the potential utility of telomerase detection and inhibition for cancer, and telomerase activation for degenerative diseases. The specificity of the promoter for the telomerase catalytic gene and the antigenicity of the protein product, hTERT, provide additional strategies for killing telomerase-positive tumor cells. Unfortunately, the strong link between telomerase and cancer has led some to confuse telomerase activation with cancer, and others to overstate the cancer risk of telomerase activation therapies for degenerative diseases. This review clarifies the difference between telomerase, which does not cause growth deregulation, and oncogenes, which do. It also addresses the concept of telomerase repression as a tumor suppressor mechanism early in life, with detrimental tissue degeneration and tumor-promoting consequences late in life. This extended view of the telomere hypothesis helps explain how telomerase inhibition can be therapeutic in cancer patients, while controlled telomerase activation for degenerative diseases may actually reduce, rather than increase, the frequency of age-related tumorigenesis.  相似文献   
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North America's first medically supervised safer injecting facility (SIF) recently opened in Vancouver, Canada. One of the concerns prior to the SIF's opening was that the facility might lead to a migration of drug activity and an increase in drug-related crime. Therefore, we examined crime rates in the neighborhood where the SIF is located in the year before versus the year after the SIF opened. No increases were seen with respect to drug trafficking (124 vs. 116) or assaults/robbery (174 vs. 180), although a decline in vehicle break-ins/vehicle theft was observed (302 vs. 227). The SIF was not associated with increased drug trafficking or crimes commonly linked to drug use.  相似文献   
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