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61.
Atrial overdrive pacing during wide QRS tachycardia with RBBB morphology. What is the mechanism? 下载免费PDF全文
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Subbaya Subramanian Venugopal Thayanithy Robert B West Cheng‐Han Lee Andrew H Beck Shirley Zhu Erinn Downs‐Kelly Kelli Montgomery John R Goldblum Pancras CW Hogendoorn Christopher L Corless Andre M Oliveira Sarah M Dry Torsten O Nielsen Brian P Rubin Jonathan A Fletcher Christopher DM Fletcher Matt van de Rijn 《The Journal of pathology》2010,220(1):58-70
Malignant peripheral nerve sheath tumours (MPNSTs) are aggressive soft tissue tumours that occur either sporadically or in patients with neurofibromatosis type 1. The malignant transformation of the benign neurofibroma to MPNST is incompletely understood at the molecular level. We have determined the gene expression signature for benign and malignant PNSTs and found that the major trend in malignant transformation from neurofibroma to MPNST consists of the loss of expression of a large number of genes, rather than widespread increase in gene expression. Relatively few genes are expressed at higher levels in MPNSTs and these include genes involved in cell proliferation and genes implicated in tumour metastasis. In addition, a gene expression signature indicating p53 inactivation is seen in the majority of MPNSTs. Subsequent microRNA profiling of benign and malignant PNSTs indicated a relative down‐regulation of miR‐34a in most MPNSTs compared to neurofibromas. In vitro studies using the cell lines MPNST‐14 (NF1 mutant) and MPNST‐724 (from a non‐NF1 individual) show that exogenous expression of p53 or miR‐34a promotes apoptotic cell death. In addition, exogenous expression of p53 in MPNST cells induces miR‐34a and other miRNAs. Our data show that p53 inactivation and subsequent loss of expression of miR‐34a may significantly contribute to the MPNST development. Collectively, our findings suggest that deregulation of miRNAs has a potential role in the malignant transformation process in peripheral nerve sheath tumours. Copyright © 2009 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd. 相似文献
64.
Unusual association of a unique CAG interruption in 5′ of DM1 CTG repeats with intergenerational contractions and low somatic mosaicism 下载免费PDF全文
Stéphanie Tomé Alexis Bertrand David Geneviève Yann Péréon DM contraction study group Marie Simon Jean‐Paul Bonnefont Guillaume Bassez Geneviève Gourdon 《Human mutation》2018,39(7):970-982
Myotonic dystrophy type 1 (DM1) is a dominant multisystemic disorder associated with high variability of symptoms and anticipation. DM1 is caused by an unstable CTG repeat expansion that usually increases in successive generations and tissues. DM1 family pedigrees have shown that ~90% and 10% of transmissions result in expansions and contractions of the CTG repeat, respectively. To date, the mechanisms of CTG repeat contraction remain poorly documented in DM1. In this report, we identified two new DM1 families with apparent contractions and no worsening of DM1 symptoms in two and three successive maternal transmissions. A new and unique CAG interruption was found in 5′ of the CTG expansion in one family, whereas multiple 5′ CCG interruptions were detected in the second family. We showed that these interruptions are associated with maternal intergenerational contractions and low somatic mosaicism in blood. By specific triplet‐prime PCR, we observed that CTG repeat changes (contractions/expansions) occur preferentially in 3′ of the interruptions for both families. 相似文献
65.
Phylogenetic analysis of human G9P[8] rotavirus strains circulating in Jiangsu,China between 2010 and 2016 下载免费PDF全文
Cheng Xu MD Jianguang Fu DC Jing Ai MD Jun Zhang MD Cheng Liu BD Xiang Huo MD Changjun Bao MD Yefei Zhu DM 《Journal of medical virology》2018,90(9):1461-1470
Rotavirus A (RVA) is the leading cause of acute viral gastroenteritis in children under 5 years of age worldwide. G9P[8] is a common RVA genotype that has been persistently prevalent in Jiangsu, China. To determine the genetic diversity of G9P[8] RVAs, 7 representative G9P[8] strains collected from Suzhou Children’s Hospital between 2010 and 2016 (named JS2010‐JS2016) were analyzed through whole‐genome sequencing. All evaluated strains showed the Wa‐like constellation G9‐P[8]‐I1‐R1‐C1‐M1‐A1‐N1‐T1‐E1‐H1. Furthermore, phylogenetic analysis revealed that the VP7 genes of all strains clustered into lineage G9‐III and G9‐VI. With the exception of strain JS2012 (P[8]‐4), the VP4 sequences of all strains belonged to the P[8]‐3 lineage. Sequencing further revealed that amino acid substitutions were present in the antigenic regions of the VP7 and VP4 genes of all strains. Moreover, there were multiple substitutions in antigenic sites I and II of the nonstructural protein 4 (NSP4) genes, whereas the other NSP genes were relatively conserved. In conclusion, our phylogenetic analysis of these 7 G9P[8] strains suggests that RVA varied across regions and time. Therefore, our findings suggest that continued surveillance is necessary to explore the molecular evolutionary characteristics of RVA for better prevention and treatment of acute viral gastroenteritis. 相似文献
66.
Charlotte Baker Jill Powell Dominic Le Melissa S. Creary Lori-Ann Daley Mary Anne McDonald Charmaine DM. Royal 《Journal of the National Medical Association》2018,110(6):564-573
Objective
To describe the perspectives and experiences of athletic trainers, coaches, and student-athletes approximately three years post-implementation of the NCAA sickle cell trait (SCT) screening policy.Participants
Two-hundred and eight student-athletes, 32 athletic trainers, and 43 coaches from 10 NCAA Division I (DI) institutions in North Carolina from January to June 2014.Methods
Two online surveys were used to assess knowledge, perspectives, and experiences.Results
Athletic staff were more supportive than student-athletes of the need for the policy. Noted challenges included variation in implementation and follow-up for SCT-positive athletes, financial costs to institutions and athletes, and timing of the screening.Conclusions
More education about SCT is needed for student-athletes and athletic staff in order to help make the implementation more successful. All parties need to be in agreement regarding the importance of knowing which student-athletes have SCT and how that information will be utilized. 相似文献67.
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Cees DM Ruijs Bregje D Onwuteaka-Philipsen Gerrit van der Wal Ad JFM Kerkhof 《BMC palliative care》2009,8(1):16-10
Background
Unbearable suffering is an important issue in end-of-life decisions. However, there has been no systematic, prospective, patient-oriented research which has focused on unbearable suffering, nor is there a suitable measurement instrument. This article describes the methodological development of a quantitative instrument to measure the nature and intensity of unbearable suffering, practical aspects of its use in end-stage cancer patients in general practice, and studies content validity and psychometric properties. 相似文献70.
PD Dr. S.T. Schindera C. Nauer R. Treier P. Trueb G. von Allmen P. Vock Z. Szucs-Farkas 《Der Radiologe》2010,50(12):1120-1127
The rapid technical advances in computed tomography have led to an increased number of clinical indications. Unfortunately, at the same time the radiation exposure to the population has also increased due to the increased total number of CT examinations. In the last few years various publications have demonstrated the feasibility of radiation dose reduction for CT examinations with no compromise in image quality and loss in interpretation accuracy. The majority of the proposed methods for dose optimization are easy to apply and are independent of the detector array configuration. This article reviews indication-dependent principles (e.g. application of reduced tube voltage for CT angiography, selection of the collimation and the pitch, reducing the total number of imaging series, lowering the tube voltage and tube current for non-contrast CT scans), manufacturer-dependent principles (e.g. accurate application of automatic modulation of tube current, use of adaptive image noise filter and use of iterative image reconstruction) and general principles (e.g. appropriate patient-centering in the gantry, avoiding over-ranging of the CT scan, lowering the tube voltage and tube current for survey CT scans) which lead to radiation dose reduction. 相似文献