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91.
In ovarian neoplasms, BRAF, but not KRAS, mutations are restricted to low-grade serous tumours 总被引:7,自引:0,他引:7
Sieben NL Macropoulos P Roemen GM Kolkman-Uljee SM Jan Fleuren G Houmadi R Diss T Warren B Al Adnani M De Goeij AP Krausz T Flanagan AM 《The Journal of pathology》2004,202(3):336-340
Genes of the RAF family, which mediate cellular responses to growth signals, encode kinases that are regulated by RAS and participate in the RAS/RAF/MEK/ERK/MAP-kinase pathway. Activating mutations in BRAF have recently been identified in melanomas, colorectal cancers, and thyroid and ovarian tumours. In the present study, an extensive characterization of BRAF and KRAS mutations has been performed in 264 epithelial and non-epithelial ovarian neoplasms. The epithelial tumours ranged from adenomas and borderline neoplasms to invasive carcinomas including serous, mucinous, clear cell, and endometrioid lesions. It is shown that BRAF mutations in ovarian tumours occur exclusively in low-grade serous neoplasms (33 of 91, 36%); these included serous borderline tumours (typical and micropapillary variants), an invasive micropapillary carcinoma and a psammocarcinoma. KRAS mutations were identified in 26 of 91 (29.5%) low-grade serous tumours, 7 of 49 (12%) high-grade serous carcinomas, 2 of 6 mucinous adenomas, 22 of 28 mucinous borderline tumours, and 10 of 18 mucinous carcinomas. Of note, two serous borderline tumours were found to harbour both BRAF and KRAS mutations. The finding that at least 60% of serous borderline tumours harbour mutations in two members of the ERK-MAP-kinase pathway (BRAF 36%, KRAS 30%) compared with 12% of high-grade serous carcinomas (BRAF 0%, KRAS 12%) indicates that the majority of serous borderline tumours do not progress to serous carcinomas. Furthermore, no BRAF mutations were detected in the other 173 ovarian tumours in this study. 相似文献
92.
Tim Martin Mark A McDaniel Melissa J Guynn Jon M Houck C Chad Woodruff Joel Pearson Bish Sandra N Moses Dubravko Kici? Claudia D Tesche 《International journal of psychophysiology》2007,64(3):247-258
We measured brain activity using magnetoencephalography in five participants during ongoing tasks that included prospective memory, retrospective memory, and oddball trials. Sources were identified in the hippocampal formation and posterior parietal and frontal lobes. Posterior parietal cortex activation had an earlier onset in the prospective memory condition than retrospective memory or oddball conditions, a higher level of theta activity in the retrospective condition, and higher levels of upper alpha in the prospective and oddball conditions. Activation of the hippocampal formation had a longer duration in the retrospective memory and prospective memory conditions than the oddball condition, but prominent alpha and theta band activity was present in all three conditions. We interpret the early (87 ms) onset of activity in parietal cortex as evidence for an initial noticing of appropriate conditions for a PM response. Hippocampal activity may reflect a subsequent memory search for the intended action. 相似文献
93.
Vincenzo Cerundolo Adrian Kelly Tim Elliott John Trowsdale Alain Townsend 《European journal of immunology》1995,25(2):554-562
The B cell line 721.174 has lost the ability to present intracellular antigens to major histocompatibility complex (MHC) class I-restricted cytotoxic T lymphocytes (CTL). This phenotype results from a homozygous deletion in the MHC that includes the peptide transporter genes TAP1 and TAP2, and the proteasome subunits LMP2 and LMP7. Recent work has shown that such cells transfected with TAP genes load their class I molecules with endogenous peptides, and present several viral epitopes to class I-restricted CTL. These data implied that the LMP2 and LMP7 genes were not required for the presentation of most epitopes through class I molecules. By contrast, while confirming the previous reports, we have identified several epitopes that appear to require genes in the MHC in addition to the TAP for their presentation. Further analysis localizes the defect to proteolysis in the cytosol. In one case, presentation could be partially restored by re-expression of full-length LMP7. Control experiments with LMP7, from which the putative pro-region had been removed, failed to restore presentation, and this lack of effect correlated with failure of the shortened LMP7 to incorporate into the proteasome. These results suggest a role for LMP7 in the generation of a viral epitope, but leave open the possibility that additional genes within the .174 deletion are required for full restoration of antigen presentation. 相似文献
94.
95.
Tim A Holt David Stables Julia Hippisley-Cox Shaun O'Hanlon Azeem Majeed 《The British journal of general practice》2008,58(548):192-196
BACKGROUND: Around 1% of the UK population has diabetes that is either undiagnosed or unrecorded on practice disease registers. AIM: To estimate the number of people in UK primary care databases with biochemical evidence of undiagnosed diabetes. To develop simple practice-based search techniques to support early recognition of diabetes. DESIGN OF STUDY: Cross-sectional survey of 3 630 296 electronic records. SETTING: Four hundred and eighty UK practices contributing to the QRESEARCH database. METHOD: Electronic searches to identify people with no diabetes diagnosis in one of two categories (A and B), using the most recently recorded blood glucose measurement: random blood glucose level >or=11.1 mmol/l or fasting blood glucose level >or=7.0 mmol/l (A); either a random or a fasting blood glucose level >or=7.0 mmol/l (B). An additional outcome measure was the proportion of the population with at least one blood glucose measurement in the record. RESULTS: The number (percentage) identified in category A was 3758 (0.10% of the total population); the number in category B was 32 785 (0.90%). Projected to a practice of 7000 patients, around eight patients have biochemical evidence of undiagnosed diabetes, and 68 have results suggesting the need for further follow-up. One-third of people aged over 40 years without diabetes have a blood glucose measurement in the past 2 years in their record. CONCLUSION: People with possible undiagnosed diabetes are readily identifiable in UK primary care databases through electronic searches using blood glucose data. People with borderline levels, who may benefit from interventions to reduce their risk of progression to diabetes, can also be identified using practice-based software. 相似文献
96.
Three British physicians briefly review the final programs in a BBC series, "Doctors' Dilemmas," each consisting of a case history followed by a discussion involving health professionals, administrators, and lawyers. Taylor, an occupational physician, comments on the episode in which a company doctor is asked by management to disclose confidential information about an employee. Psychiatrist Jerram discusses his reactions to the program presenting the dilemmas of treating a patient with anorexia nervosa against her will. Forsythe, a community physician, reviews the final episode, which dealt with resource allocation, the role of health professionals within the National Health Service, and the potential conflict between the NHS and private practice. 相似文献
97.
Fürstenau Daniel Haneke Hannah Spies Claudia Walz Tim Schewina Kai Höft Moritz Mörgeli Rudolf Balzer Felix 《Zeitschrift fur Gesundheitswissenschaften》2022,30(1):99-110
Journal of Public Health - The purpose of this paper is to investigate the implementation of value-based care principles in the context of frailty in the perioperative process, highlighting the... 相似文献
98.
Tudor Kate Maloney Shannon Raja Anam Baer Ruth Blakemore Sarah-Jayne Byford Sarah Crane Catherine Dalgleish Tim De Wilde Katherine Ford Tamsin Greenberg Mark Hinze Verena Lord Liz Radley Lucy Opaleye Emerita Satiro Taylor Laura Ukoumunne Obioha C. Viner Russell Kuyken Willem Montero-Marin Jesus 《Prevention science》2022,23(6):934-953
Prevention Science - There is evidence that universal school-based mindfulness training (SBMT) can have positive effects for young people. However, it is unknown who benefits most from such... 相似文献
99.
Stephen D. Clark Becky Shute Victoria Jenneson Tim Rains Mark Birkin Michelle A. Morris 《Nutrients》2021,13(5)
Poor diet is a leading cause of death in the United Kingdom (UK) and around the world. Methods to collect quality dietary information at scale for population research are time consuming, expensive and biased. Novel data sources offer potential to overcome these challenges and better understand population dietary patterns. In this research we will use 12 months of supermarket sales transaction data, from 2016, for primary shoppers residing in the Yorkshire and Humber region of the UK (n = 299,260), to identify dietary patterns and profile these according to their nutrient composition and the sociodemographic characteristics of the consumer purchasing with these patterns. Results identified seven dietary purchase patterns that we named: Fruity; Meat alternatives; Carnivores; Hydrators; Afternoon tea; Beer and wine lovers; and Sweet tooth. On average the daily energy intake of loyalty card holders -who may buy as an individual or for a household- is less than the adult reference intake, but this varies according to dietary purchase pattern. In general loyalty card holders meet the recommended salt intake, do not purchase enough carbohydrates, and purchase too much fat and protein, but not enough fibre. The dietary purchase pattern containing the highest amount of fibre (as an indicator of healthiness) is bought by the least deprived customers and the pattern with lowest fibre by the most deprived. In conclusion, supermarket sales data offer significant potential for understanding population dietary patterns. 相似文献
100.
We report a norovirus GIV outbreak in the United States, 15 years after the last reported outbreak. During May 2016 in Wisconsin, 53 persons, including 4 food handlers, reported being ill. The outbreak was linked to individually prepared fruit consumed as a fruit salad. The virus was phylogenetically classified as a novel GIV genotype. 相似文献