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81.
PURPOSE: To investigate variations of circulating serum levels of interleukin-6 (IL-6), tumor necrosis factor alpha (TNFalpha), and interleukin-10 (IL-10) during three-dimensional conformal radiation therapy (3D-CRT) in patients with non-small-cell lung cancer and correlate these variations with the occurrence of radiation pneumonitis. PATIENTS AND METHODS: Ninety-six patients receiving 3D-CRT for stage I to III disease were evaluated prospectively. Circulating cytokine levels were determined before, every 2 weeks during, and at the end of treatment. Radiation pneumonitis was evaluated prospectively between 6 and 8 weeks after 3D-CRT. The predictive value of clinical, dosimetric, and biologic (cytokine levels) factors was evaluated both in univariate and multivariate analyses. RESULTS: Forty patients (44%) experienced score 1 or more radiation pneumonitis. No association was found between baseline cytokine levels and the risk of radiation pneumonitis. In the whole population, mean levels of TNFalpha, IL-6, and IL-10 remained stable during radiotherapy. IL-6 levels were significantly higher (P = .047) during 3D-CRT in patients with radiation pneumonitis. In the multivariate analysis, covariations of IL-6 and IL-10 levels during the first 2 weeks of 3D-CRT were evidenced as independently predictive of radiation pneumonitis in this series (P = .011). CONCLUSION: Early variations of circulating IL-6 and IL-10 levels during 3D-CRT are significantly associated with the risk of radiation pneumonitis. Variations of circulating IL-6 and IL-10 levels during 3D-CRT may serve as independent predictive factors for this complication.  相似文献   
82.
BackgroundRisk-adjusted cancer screening and prevention is a promising and continuously emerging option for improving cancer prevention. It is driven by increasing knowledge of risk factors and the ability to determine them for individual risk prediction. However, there is a knowledge gap between evidence of increased risk and evidence of the effectiveness and efficiency of clinical preventive interventions based on increased risk. This gap is, in particular, aggravated by the extensive availability of genetic risk factor diagnostics, since the question of appropriate preventive measures immediately arises when an increased risk is identified. However, collecting proof of effective preventive measures, ideally by prospective randomized preventive studies, typically requires very long periods of time, while the knowledge about an increased risk immediately creates a high demand for action.SummaryTherefore, we propose a risk-adjusted prevention concept that is based on the best current evidence making needed and appropriate preventive measures available, and which is constantly evaluated through outcome evaluation, and continuously improved based on these results. We further discuss the structural and procedural requirements as well as legal and socioeconomical aspects relevant for the implementation of this concept.  相似文献   
83.
Abstract

Crossborder curriculum partnerships are a relatively new and fast-growing form of internationalization in which the curriculum that has been developed by one institution (the home institution) crosses borders and is implemented in another institution (the host institution). These partnerships aim to provide comparable learning experiences to the students in both institutions and are driven by a variety of motives, such as strengthening international networks, increasing financial gains, and stimulating research spinoffs. Although popular, crossborder curriculum partnerships are also criticized for their potentially low educational quality, failing to address fundamental differences in teaching and learning between the home and host institutions, and not addressing the educational needs of the host country’s health care system. Our aim is to provide guidance to those considering or engaged in designing, developing, managing, and reviewing a crossborder curriculum partnership or other forms of international educational partnerships in medical education. Drawing from research, personal, and institutional experiences in this area, we listed twelve tips categorized into four themes, which contribute to the establishment of sustainable partnerships that can withstand the aforementioned criticism.  相似文献   
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85.
Mechanisms of hepatotoxicity.   总被引:22,自引:0,他引:22  
This review addresses recent advances in specific mechanisms of hepatotoxicity. Because of its unique metabolism and relationship to the gastrointestinal tract, the liver is an important target of the toxicity of drugs, xenobiotics, and oxidative stress. In cholestatic disease, endogenously generated bile acids produce hepatocellular apoptosis by stimulating Fas translocation from the cytoplasm to the plasma membrane where self-aggregation occurs to trigger apoptosis. Kupffer cell activation and neutrophil infiltration extend toxic injury. Kupffer cells release reactive oxygen species (ROS), cytokines, and chemokines, which induce neutrophil extravasation and activation. The liver expresses many cytochrome P450 isoforms, including ethanol-induced CYP2E1. CYP2E1 generates ROS, activates many toxicologically important substrates, and may be the central pathway by which ethanol causes oxidative stress. In acetaminophen toxicity, nitric oxide (NO) scavenges superoxide to produce peroxynitrite, which then causes protein nitration and tissue injury. In inducible nitric oxide synthase (iNOS) knockout mice, nitration is prevented, but unscavenged superoxide production then causes toxic lipid peroxidation to occur instead. Microvesicular steatosis, nonalcoholic steatohepatitis (NASH), and cytolytic hepatitis involve mitochondrial dysfunction, including impairment of mitochondrial fatty acid beta-oxidation, inhibition of mitochondrial respiration, and damage to mitochondrial DNA. Induction of the mitochondrial permeability transition (MPT) is another mechanism causing mitochondrial failure, which can lead to necrosis from ATP depletion or caspase-dependent apoptosis if ATP depletion does not occur fully. Because of such diverse mechanisms, hepatotoxicity remains a major reason for drug withdrawal from pharmaceutical development and clinical use.  相似文献   
86.
Based on epidemiological data available through long-term monitoring surveys conducted by both the Public Health Directorate and the Louis Malardé Institute, ciguatera is highly endemic in French Polynesia, most notably in Raivavae (Australes) which appears as a hot spot of ciguatera with an average incidence rate of 140 cases/10,000 population for the period 2007-2008. In order to document the ciguatera risk associated with Raivavae lagoon, algal and toxin-based field monitoring programs were conducted in this island from April 2007 to May 2008. Practically, the distribution, abundance and toxicity of Gambierdiscus populations, along with the toxicity levels in 160 fish distributed within 25 distinct species, were assessed in various sampling locations. Herbivores such as Scarids (parrotfish) and Acanthurids (unicornfish) were rated as high-risk species based on receptor-binding assay toxicity data. A map of the risk stratification within the Raivavae lagoon was also produced, which indicates that locations where both natural and man-made disturbances have occurred remained the most susceptible to CFP incidents. Our findings also suggest that, locally, the traditional knowledge about ciguatera may not be scientifically complete but is functionally correct. Community education resulted in self-regulating behaviour towards avoidance of high-risk fish species and fishing locations.  相似文献   
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89.
Oocyte donors are chosen among phenotypically normal and fertile women who are not expected to carry any chromosomal abnormality. A high incidence of balanced structural chromosomal rearrangements has been found within oocyte donors. This result raises the question of a possible bias in their recruitment with respect to their familial background and/or personal reproductive history.  相似文献   
90.
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