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Zusammenfassung Männliche Goldhamster wurden durch Magensonde mit Diäthylnitrosamin, einem bei der Ratte stark leberwirksamen Carcinogen behandelt. Nach zweimonatiger Behandlung zeigten 13 Tiere eine hochgradige diffuse z. T. papilläre Plattenepithelmetaplasie des Tracheobronchialbaumes. Die ersten Carcinome der Lunge traten, mit einer Ausnahme in der 7. Woche, nach 9 Wochen auf. Von den über 2-5/12 Monate behandelten Tieren zeigten 36 z. T. multiple Lunge- und Trachealcarcinome. Bei diesen Carcinomen handelt es sich um verhornte und unverhornte Plattenepithelcarcinome. Bei der Diskussion wird auf die genetischen Faktoren bei der Carcinogenese in der Lunge eingegangen.
Mit 6 Textabbildungen
Die Untersuchungen wurden mit Unterstützung der Deutschen Forschungsgesellschaft durchgeführt. 相似文献
Summary By means of gavage male gold hamsters were fed di-ethyl-nitrosamine, a potent liver carcinogen in the rat. After two months of treatment a severe diffuse, in part papillary, squanmous metaplasia of the tracheobronchial tree occurred in 13 animals. The first carcinoma of the lung appeared after nine weeks with one exception in the 7th week. Of the animals treated from two to five and a half months 36 showed in part multiple pulmonary and tracheal carcinomas. These carcinomas were hornified and non-hornified squamous epithelial carcinomas. The genetic factors of carcinogenesis of the lung are discussed.
Mit 6 Textabbildungen
Die Untersuchungen wurden mit Unterstützung der Deutschen Forschungsgesellschaft durchgeführt. 相似文献
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Prof. Dr. med. Uwe Janssens Prof. Dr. med. Hilmar Burchardi Univ.-Prof. Dr. med. Gunnar Duttge Renate Erchinger Dr. med. Peter Gretenkort Prof. Dr. med. Michael Mohr Univ.-Prof. Dr. med. Friedemann Nauck Sonja Roth?rmel Prof. Dr. med. Fred Salomon Univ.-Prof. Dr. med. P. Schmucker PD Dr. phil. Alfred Simon Prof. Dr. med. Herwig Stopfkuchen Prof. Dr. med. Andreas Valentin Univ.-Prof. Dr. med. Norbert Weiler Dr. med. Gerald Neitzke 《MedR Medizinrecht》2012,30(10):647-650
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The capacity of polyadenylate-binding protein PABPC1 (PABP1) to stimulate translation is regulated by its repressor, Paip2. Paradoxically, while PABP accumulation promotes human cytomegalovirus (HCMV) protein synthesis, we show that this is accompanied by an analogous increase in the abundance of Paip2 and EDD1, an E3 ubiquitin ligase that destabilizes Paip2. Coordinate control of PABP1, Paip2, and EDD1 required the virus-encoded UL38 mTORC1 activator and resulted in augmented Paip2 synthesis, stability, and association with PABP1. Paip2 synthesis also increased following serum stimulation of uninfected normal fibroblasts, suggesting that this coregulation may play a role in how uninfected cells respond to stress. Significantly, Paip2 accumulation was dependent on PABP accrual, as preventing PABP1 accumulation suppressed viral replication and inhibited the corresponding Paip2 increase. Furthermore, depleting Paip2 restored the ability of infected cells to assemble the translation initiation factor eIF4F, promoting viral protein synthesis and replication without increasing PABP1. This establishes a new role for the cellular PABP1 inhibitor Paip2 as an innate defense that restricts viral protein synthesis and replication. Moreover, it illustrates how a stress-induced rise in PABP1 triggered by virus infection can counter and surpass a corresponding increase in Paip2 abundance and stability. 相似文献
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Adolescence has long been regarded as a transition from childhood to adulthood. More recently it is become a concern of those wishing to avoid adverse health outcomes during middle and late adulthood. Most of this effort has been focused on behavioural risk factors such as tobacco and excessive alcohol use, physical exercise habits, dietary habits, as well as sexual and injury-related behaviours. The concern is that these habits are established during adolescence, continue into adulthood, and come to constitute ongoing risk factors for adverse health outcomes during middle and late adulthood. There is good reason to criticize this approach. These behaviours are themselves shaped by adolescents’ living and working conditions and even then constitute a small proportion of the variance predicting adverse health outcomes during adulthood. More complex models of how adolescence serves as a gateway to adult health outcomes are presented. These are the socio-environmental, public policy, and political economy approaches. The argument is made that adolescence is a period during which public policy plays an especially important role in predicting future health outcomes. Yet, these public policies influence health all across the life span with adolescence providing only one of many important periods during which public policy shapes health prospects during middle and later adulthood. Ultimately one should consider a range of approaches ranging from the behavioural to the political to examine how adolescence serves as a gateway towards future adult prospects. An Adolescent Gateway Towards Adult Health Model is provided to assist in this process. 相似文献
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Stephen M. Schueller Ph.D. Adrian Aguilera Ph.D. David C. Mohr Ph.D. 《Depression and anxiety》2017,34(6):540-545
Ecological momentary interventions (EMIs) are becoming more popular and more powerful resources for the treatment and prevention of depression and anxiety due to advances in technological capacity and analytic sophistication. Previous work has demonstrated that EMIs can be effective at reducing symptoms of depression and anxiety as well as related outcomes of stress and at increasing positive psychological functioning. In this review, we highlight the differences between EMIs and other forms of treatment due to the nature of EMIs to be deeply integrated into the fabric of people's day-to-day lives. EMIs require unique considerations in their design, deployment, and evaluation. Furthermore, given that EMIs have been advanced by changes in technologies and that the use of behavioral intervention technologies for mental health has been increasing, we discuss how technologies and analytics might usher in a new era of EMIs. Future EMIs might reduce user burden and increase intervention personalization and sophistication by leveraging digital sensors and advances in natural language processing and machine learning. Thus, although current EMIs are effective, the EMIs of the future might be more engaging, responsive, and adaptable to different people and different contexts. 相似文献
130.
Ana R Dur?o Pisha Pittayapat Maria Ivete B Rockenbach Raphael Olszewski Suk Ng Afonso P Ferreira Reinhilde Jacobs 《Progress in orthodontics》2013,14(1):31
Lateral cephalometric radiography is commonly used as a standard tool in orthodontic assessment and treatment planning. The aim of this study was to evaluate the available scientific literature and existing evidence for the validation of using lateral cephalometric imaging for orthodontic treatment planning. The secondary objective was to determine the accuracy and reliability of this technique. We did not attempt to evaluate the value of this radiographic technique for other purposes. A literature search was performed using specific keywords on electronic databases: Ovid MEDLINE, Scopus and Web of Science. Two reviewers selected relevant articles, corresponding to predetermined inclusion criteria. The electronic search was followed by a hand search of the reference lists of relevant papers. Two reviewers assessed the level of evidence of relevant publications as high, moderate or low. Based on this, the evidence grade for diagnostic efficacy was rated as strong, moderately strong, limited or insufficient. The initial search revealed 784 articles listed in MEDLINE (Ovid), 1,034 in Scopus and 264 articles in the Web of Science. Only 17 articles met the inclusion criteria and were selected for qualitative synthesis. Results showed seven studies on the role of cephalometry in orthodontic treatment planning, eight concerning cephalometric measurements and landmark identification and two on cephalometric analysis. It is surprising that, notwithstanding the 968 articles published in peer-reviewed journals, scientific evidence on the usefulness of this radiographic technique in orthodontics is still lacking, with contradictory results. More rigorous research on a larger study population should be performed to achieve full evidence on this topic. 相似文献