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61.
Steven Habbous Karen P. Chu Xin Qiu Anthony La Delfa Luke T.G. Harland Ehab Fadhel Angela Hui Bayardo Perez-Ordonez Ilan Weinreb Fei-Fei Liu John Waldron Brian O'Sullivan David Goldstein Wei Xu Shao Hui Huang Geoffrey Liu 《Cancer epidemiology》2013,37(6):820-829
Introduction Human papillomavirus (HPV) is a risk and prognostic factor for oropharyngeal cancer (OPC). Determining whether the incidence of HPV-associated OPC is rising informs health policy. Methods HPV status was ascribed using p16 immunohistochemistry in 683/1474 OPC patients identified from the Princess Margaret Hospital's Cancer Registry (from 2000 to 2010). Missing p16 data was estimated using multiple (n = 100) imputation (MI) and validated using an independent OPC cohort (n = 214). Non-OPC head and neck squamous cell carcinoma (HNSCC) (n = 3262) were also used for time-trend comparison. Regression was used to compare HNSCC subsets and time-trends. The c-index was used to measure the predictive ability of MI. Results The incidence of OPC rose from 23.3% of all HNSCC in 2000 to 31.2% in 2010 (p = 0.002). In the subset of OPC tested for p16, there was no change in p16 positivity over time (p = 0.9). However, p16 testing became more frequent over time (p < 0.0001), but was nonetheless biased, favouring never-smokers [OR 1.87 (95% CI 1.29–2.70)] and tumors of the tonsil [OR 2.30 (1.52–3.47)] or base-of-tongue [OR 1.72 (1.10–2.70)]. These same factors were also associated with p16-positivity [ORs 3.22 (1.27–8.16), 7.26 (3.50–15.1), 5.83 (2.70–12.7), respectively]. Following MI and normalization, the proportion of OPC that was p16-associated rose from 39.8% in 2000 to 65.0% in 2010, p = 0.002, fully explaining the rise in OPC in our patient population. Conclusion The rise in HNSCC referrals seen from 2000 to 2010 at our institution was driven primarily by p16-associated OPC. MI was necessary to derive reliable conclusions when cases with missing data are considerable. 相似文献
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Yaron Ilan 《Cell biology international》2019,43(7):739-748
Microtubules (MTs) play roles in regulating the mechanical structure and dynamics of cells. While MTs appear to be highly ordered structures, recent data suggest some randomness in their structure and dynamics. Part of this inherent randomness is attributed to errors and correction mechanisms are being investigated to overcome these ‘mistakes.’ However, this randomness may also be part of the normal intracellular function of MTs. It is possible that random events in MT structure and dynamics may contribute to their normal function and may even be part of an improved efficacy mechanism. An alternative view, wherein MT and kinetochore errors are part of required cell plasticity, is also discussed. These data may further support the concept of randomness in biological pathways as part of self‐organization or accurate and enhanced function. 相似文献
64.
Friedberg I Nika K Tautz L Saito K Cerignoli F Friedberg I Godzik A Mustelin T 《FEBS letters》2007,581(13):2527-2533
A novel human dual-specific protein phosphatase (DSP), designated DUSP27, is here described. The DUSP27 gene contains three exons, rather than the predicted 4-14 exons, and encodes a 220 amino acid protein. DUSP27 is structurally similar to other small DSPs, like VHR and DUSP13. The location of DUSP27 on chromosome 10q22, 50 kb upstream of DUSP13, suggests that these two genes arose by gene duplication. DUSP27 is an active enzyme, and its kinetic parameters and were determined. DUSP27 is a cytosolic enzyme, expressed in skeletal muscle, liver and adipose tissue, suggesting its possible role in energy metabolism. 相似文献
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Engel CC Locke S Reissman DB DeMartino R Kutz I McDonald M Barsky AJ 《Biosecurity and bioterrorism : biodefense strategy, practice, and science》2007,5(2):155-163
The global war on terrorism has led to increased concern about the ability of the U.S. healthcare system to respond to casualties from a chemical, biological, or radiological agent attack. Relatively little attention, however, has focused on the potential, in the immediate aftermath of such an attack, for large numbers of casualties presenting to triage points with acute health anxiety and idiopathic physical symptoms. This sort of "mass idiopathic illness" is not a certain outcome of chemical, biological, or radiological attack. However, in the event that this phenomenon occurs, it could result in surges in demand for medical evaluations that may disrupt triage systems and endanger lives. Conversely, if continuous primary care is not available for such patients after initial triage, many may suffer with unrecognized physical and emotional injuries and illness. This report is the result of an expert planning initiative seeking to facilitate triage protocols that will address the possibility of mass idiopathic illness and bolster healthcare system surge capacity. The report reviews key triage assumptions and gaps in knowledge and offers a four-stage triage model for further discussion and research. Optimal triage approaches offer flexibility and should be based on empirical studies, critical incident modeling, lessons from simulation exercises, and case studies. In addition to staging, the proposed triage and longitudinal care model relies on early recognition of symptoms, development of a registry, and use of non-physician care management to facilitate later longitudinal followup and collaboration between primary care and psychiatry for the significant minority of patients who develop persistent idiopathic symptoms associated with reduced functional status. 相似文献
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H C Wang B Beer D Sassano A J Blume M R Ziai 《The International journal of biochemistry》1991,23(3):271-276
1. Gene expression in Xenopus oocytes is now an integral part of many molecular cloning strategies. 2. For some genes, such as those encoding the ion channels, this system has emerged as the only available means to authenticate and examine the biological activities of the cloned DNA. 3. This review discusses some of the current applications of Xenopus oocytes in modern molecular biology. 相似文献
70.
Nicola Bryson-Morrison Andy Beer Aly Gaspard Soumah Tetsuro Matsuzawa Tatyana Humle 《American journal of primatology》2020,82(3):e23102
Agricultural expansion encroaches on tropical forests and primates in such landscapes frequently incorporate crops into their diet. Understanding the nutritional drivers behind crop-foraging can help inform conservation efforts to improve human-primate coexistence. This study builds on existing knowledge of primate diets in anthropogenic landscapes by estimating the macronutrient content of 24 wild and 11 cultivated foods (90.5% of food intake) consumed by chimpanzees (Pan troglodytes verus) at Bossou, Guinea, West Africa. We also compared the macronutrient composition of Bossou crops to published macronutrient measures of crops from Bulindi, Uganda, East Africa. The composition of wild fruits, leaves, and pith were consistent with previous reports for primate diets. Cultivated fruits were higher in carbohydrates and lower in insoluble fiber than wild fruits, while wild fruits were higher in protein. Macronutrient content of cultivated pith fell within the ranges of consumed wild pith. Oil palm food parts were relatively rich in carbohydrates, protein, lipids, and/or fermentable fiber, adding support for the nutritional importance of the oil palm for West African chimpanzees. We found no differences in the composition of cultivated fruits between Bossou and Bulindi, suggesting that macronutrient content alone does not explain differences in crop selection. Our results build on the current understanding of chimpanzee feeding ecology within forest-agricultural mosaics and provide additional support for the assumption that crops offer primates energetic benefits over wild foods. 相似文献