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991.
Wakefield RJ D'Agostino MA Iagnocco A Filippucci E Backhaus M Scheel AK Joshua F Naredo E Schmidt WA Grassi W Moller I Pineda C Klauser A Szkudlarek M Terslev L Balint P Bruyn GA Swen WA Jousse-Joulin S Kane D Koski JM O'Connor P Milutinovic S Conaghan PG;OMERACT Ultrasound Group 《The Journal of rheumatology》2007,34(4):848-851
Ultrasound (US) is a relatively new imaging modality in rheumatology that offers great potential as a diagnostic and management tool. In 2004, an OMERACT Ultrasound Special Interest Group was formed to address the metric qualities of US as a potential outcome measure. A preliminary systematic review highlighted the deficiencies in the literature, particularly with regard to the reliability of interpreting and acquiring images; as a consequence, a number of exercises were proposed to address these issues. This report describes a series of iterative studies that have resulted in improved intra- and inter-reader reliability for detecting and scoring synovitis from both static and real-time images of the hand joints of patients with rheumatoid arthritis. The reliability of acquiring images was also enhanced using standardized positions. Future studies will assess the value of US in clinical trials. 相似文献
992.
993.
Correlation between mechanical strength of messenger RNA pseudoknots and ribosomal frameshifting 下载免费PDF全文
Hansen TM Reihani SN Oddershede LB Sørensen MA 《Proceedings of the National Academy of Sciences of the United States of America》2007,104(14):5830-5835
Programmed ribosomal frameshifting is often used by viral pathogens including HIV. Slippery sequences present in some mRNAs cause the ribosome to shift reading frame. The resulting protein is thus encoded by one reading frame upstream from the slippery sequence and by another reading frame downstream from the slippery sequence. Although the mechanism is not well understood, frameshifting is known to be stimulated by an mRNA structure such as a pseudoknot. Here, we show that the efficiency of frameshifting relates to the mechanical strength of the pseudoknot. Two pseudoknots derived from the Infectious Bronchitis Virus were used, differing by one base pair in the first stem. In Escherichia coli, these two pseudoknots caused frameshifting frequencies that differed by a factor of two. We used optical tweezers to unfold the pseudoknots. The pseudoknot giving rise to the highest degree of frameshifting required a nearly 2-fold larger unfolding force than the other. The observed energy difference cannot be accounted for by any existing model. We propose that the degree of ribosomal frameshifting is related to the mechanical strength of RNA pseudoknots. Our observations support the "9 A model" that predicts some physical barrier is needed to force the ribosome into the -1 frame. Also, our findings support the recent observation made by cryoelectron microscopy that mechanical interaction between a ribosome and a pseudoknot causes a deformation of the A-site tRNA. The result has implications for the understanding of genetic regulation, reading frame maintenance, tRNA movement, and unwinding of mRNA secondary structures by ribosomes. 相似文献
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995.
Trine Silkjaer Jan Maxwell Nørgaard Anni Aggerholm Lene Hyldahl Ebbesen Eigil Kjeldsen Peter Hokland Charlotte Guldborg Nyvold 《European journal of haematology》2013,90(5):385-396
Recent studies have suggested that mutations in the mitochondrial genome (mtDNA) may play a role in the development and response to treatment for human cancer. The aim of this study was to investigate whether mtDNA variations have any prognostic relevance, to clarify the spectra of mtDNA variation and to determine whether there was any correlation to known prognostic factors in acute myeloid leukemia (AML). To elucidate this, we sequenced the entire mtDNA in 56 AML patients and 14 control subjects. When analyzing the biologic impact of the non‐synonymous variations in the mtDNA coding genes, we found an inferior disease‐free survival for patients exhibiting variations in the two most important catalytic genes of the complex IV of the oxidative phosphorylation complexes (OXPHOS), that is, the cytochrome c oxidase subunit I and the cytochrome c oxidase subunit II (hazard ratio 2.6, P = 0.03; multivariate analysis). In addition, the most frequent variation was the T16311C in the control region, which was found in 11 (20%) of the 56 patients. This observation was confirmed in another cohort of 173 diagnostic AML samples. In this expanded group, the T16311C variation tended to be associated with chromosomal abnormalities. 相似文献
996.
997.
A suicide attempt is a significant burden on the suicidal person, the family, and the community. The psychosocial strain on parents after their offspring’s suicide attempt is significant. The aim of this study was to gain insight into how a parent’s relationship with a partner was affected after their son or daughter’s suicide attempt or serious suicide threats. Individual in-depth interviews were made of 19 parents recruited through a Danish non-governmental organisation in 2013. Data were analysed using a generic thematic analysis. A key category “Sense of solidarity” and two sub-categories “Challenges to the relationship” and “Responding to different reactions and coping strategies” were constructed. Sense of solidarity was important for the parents’ co-parenting and how they engaged with the situation as a couple. The group of participants was heterogeneous and had learned to manage the stressful situation in different ways. Interventions to support parents of sons or daughters who have attempted suicide should include a stronger focus on parents’ co-parenting abilities in the family system in order to support the well-being of the whole family. 相似文献
998.
999.
Mohit Kothari Xuemei Liu Lene Baad‐Hansen Abhishek Kumar Guo Bin Peter Svensson 《European journal of oral sciences》2016,124(6):534-539
The aim of this study was to investigate the impact of visual observational conditions on performance during a standardized tongue‐protrusion training (TPT) task and to evaluate subject‐based reports of helpfulness, disturbance, pain, and fatigue, due to the observational conditions on 0–10 numerical rating scales. Forty‐eight healthy participants performed a 1‐h standard TPT task. Participants were randomly assigned to one of the following three groups with different observational conditions: group 1, model observation (participants watched a prerecorded video showing standard TPT before optimal TPT being performed); group 2, self‐observation (participants watched live video feedback of their own TPT performance); and group 3, control group (participants performed the TPT with no conditioning). There was no overall difference between groups but TPT performance increased over time. A significant group×time interaction indicated that the self‐observation group performed significantly better than the model‐observation group in the last 20 min of TPT. The subject‐based reports of video helpfulness showed that the model‐observation group rated the prerecorded video as more helpful for TPT performance compared with the other groups but there was no significant difference between groups regarding the level of disturbance, pain, or fatigue. Self‐observation of tongue‐training facilitated behavioral aspects of tongue motor learning compared with model observation but not compared with control. 相似文献
1000.
Beth Mastel-Smith Brenda Binder Ann Malecha Gayle Hersch Lene Symes Judith McFarlane 《Issues in mental health nursing》2013,34(10):1037-1049
The purpose of the study was to test a psychosocial intervention, therapeutic life review, offered by home care workers to decrease depression among home-dwelling older women. A quasi-experimental, one-group time-series design measured the effect of a once-a-week, 40-minute therapeutic life review intervention, delivered for six weeks by home care workers, on the depression scores of women 65 years and older, compared to their scores during the ten weeks prior to the intervention. Over time, depression scores improved with a significant decrease in depression immediately following the six-week intervention. Based on these findings, we concluded that home care workers can deliver a community-based psychosocial intervention that decreases depression in their home-dwelling clients. 相似文献