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61.
OBJECTIVES: To assess how personal digital assistants (PDAs) perform as collection tools of patient-reported outcomes in clinical research compared to pen and paper (P&P) diaries in terms of feasibility, protocol compliance, data accuracy, and subject acceptability. STUDY DESIGN AND SETTING: A systematic review of randomized and quasi-randomized controlled trials comparing the PDA and P&P methods in a health diary context involving repeated measures in persons with chronic health problems. RESULTS: Nine studies were included. Their methodological quality was variable. Five studies reported on feasibility, and all reported technical difficulties with the PDA technology. Two studies reported that electronic collection leads to a substantial reduction in time used for data handling. Five studies reported that the PDA method results in better compliance, whereas one study reported the opposite. All three articles reporting on data accuracy indicated that there are fewer errors in the PDA records. Four articles scrutinized subject preference, and the PDA method came out favorably in all four. CONCLUSION: The PDA method seems to perform better than P&P in most of the selected outcomes. Technical malfunction is the chief disadvantage with the PDA method. Further research comparing PDA with paper data collection using more stringent methodology is needed. 相似文献
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We present an overview of selected computational methods for microRNA prediction. It is especially aimed at viral miRNA detection. As the number of microRNAs increases and the range of genomes encoding miRNAs expands, it seems that these small regulators have a more important role than has been previously thought. Most microRNAs have been detected by cloning and Northern blotting, but experimental methods are biased towards abundant microRNAs as well as being time-consuming. Computational detection methods must therefore be refined to serve as a faster, better, and more affordable method for microRNA detection. We also present data from a small study investigating the problems of computational miRNA prediction. Our findings suggest that the prediction of microRNA precursor candidates is fairly easy, while excluding false positives as well as exact prediction of the mature microRNA is hard. Finally, we discuss possible improvements to computational microRNA detection. 相似文献
66.
Syse A Lyngstad TH Kravdal O 《International journal of cancer. Journal international du cancer》2012,130(8):1870-1878
Diagnostic and treatment protocols for childhood cancer are generally standardized, and therefore, survival ought to be fairly equal across social strata in societies with free public health care readily available. Nevertheless, our study explores whether there are disparities in mortality after childhood cancer in Norway depending on socioeconomic status of parents. Limited knowledge on differentials exists from earlier analyses. Discrete-time hazard regression models for all-cause mortality for the first 10 years after diagnosis were estimated for all Norwegian children (younger than 20 years), who were diagnosed with cancer during 1974-2007 (N = 6,280), using data from five national registers. Mortality was reduced by about 15% for children with highly educated mothers and children without siblings. These effects were most pronounced for cancers predicted to encompass intense, long-lasting treatments resulting in chronic health problems. Neither earnings nor the marital status of parents affected children's survival. This large, registry-based study suggests that time constraints and various noneconomic rewards of parents from their education appears to have an impact on childhood cancer survival. It may be that children with resourceful parents are healthier at the outset and/or are more likely to avoid later health problems. It may also be that children of well-informed and strongly involved parents are offered better treatment or are able to make better use of what is offered, for instance, by adhering more closely to recommendations for follow-up treatment. The possibility of such differentials in offered and actual treatment should be addressed in future research. 相似文献
67.
Ingebrigtsen VA Boye K Tekle C Nesland JM Flatmark K Fodstad O 《International journal of cancer. Journal international du cancer》2012,131(11):2528-2536
In colorectal cancer there is a need for molecular markers that can complement the histopathological staging in predicting the likelihood of disease recurrence following curatively intended surgery. B7-H3 is an immunoregulatory protein shown to be overexpressed in several cancer forms, often associated with more advanced disease and poor prognosis. We wanted to examine whether B7-H3 could be a potential prognostic marker in colorectal cancer. Paraffin-embedded samples from 277 colorectal cancer patients were immunostained with anti-B7-H3 antibody. B7-H3 was expressed in the tumor cell cytoplasm and cell membrane in 62% and 46% of the samples, respectively. Unexpectedly, B7-H3 was expressed in the nucleus in 30% of the tumors. The nuclear localization was confirmed by Western immunoblotting of subcellular fractions. Importantly, in colon cancer, nuclear B7-H3 expression was independently and significantly associated with reduced metastasis-free, disease-specific and overall survival. B7-H3 expression in tumor-associated vasculature and fibroblasts was observed in the majority of samples, and endothelial B7-H3 expression was also significantly associated with poor outcome in colon cancer. In rectal cancer patients, the only significant association was between fibroblast B7-H3 expression and shorter metastasis-free survival. Few significant associations to clinicopathological parameters were seen. The results indicate that nuclear B7-H3 might be involved in colon cancer progression and metastasis, and suggest that nuclear B7-H3 could become a useful prognostic marker in colon cancer. 相似文献
68.
Høglend P Amlo S Marble A Bøgwald KP Sørbye O Sjaastad MC Heyerdahl O 《The American journal of psychiatry》2006,163(10):1739-1746
OBJECTIVE: The purpose of this study was to measure the effects of transference interpretations (the assumed core active ingredient) in dynamic psychotherapy, using an experimental design. METHOD: One hundred patients were randomly assigned to two groups. One group received dynamic psychotherapy over 1 year, with a moderate level of transference interpretations, while the other group received dynamic psychotherapy with no transference interpretations. The most common axis I disorders were depression and anxiety disorders. Forty-six patients fulfilled the general criteria for personality disorder. Seven experienced psychotherapists treated patients in both groups. Five full sessions from each treatment were rated by two evaluators with process measures in order to document treatment integrity. Outcome variables were the Psychodynamic Functioning Scales, Inventory of Interpersonal Problems Scale-Circumplex version, Global Assessment of Functioning Scale, and Symptom Checklist-90-R. Quality of Object Relations Scale (lifelong pattern) and personality disorders were preselected as possible moderators of treatment effects. Change was assessed using linear-mixed models. Clinically significant change was also calculated. RESULTS: The authors could not demonstrate differential treatment effects between the groups. However, the moderator analyses showed that transference interpretations were more helpful for patients with a lifelong history of less mature object relations. Small negative effects were observed for patients with mature object relations. CONCLUSIONS: The authors could not show differences in average effectiveness between treatments. However, the moderator analyses indicated that treatment worked through different active ingredients for different patients. Contrary to common expectation, patients with poor object relations profited more from therapy with transference interpretations than from therapy with no transference interpretations. 相似文献
69.
Purpose: Despite detailed knowledge of the effects of X-ray contrast media on cardiac function, no studies have examined the effect
of contrast media injections on the subsequent tolerance to ischemia in the heart.
Methods: Isolated perfused rat hearts were exposed to repetitive injections of iohexol, iodixanol, or ioxaglate before 30 min of global
ischemia and 120 min of reperfusion. These groups were compared with control (no pretreatment) and ischemic preconditioning
known to reduce infarct size. Physiologic variables and infarct size were measured
Results: Pretreatment with iodixanol reduced infarct size significantly compared with control and thus afforded protection against
ischemia. Injections with iohexol and ioxaglate reduced infarct size, although not significantly, compared with control.
Conclusion: Pretreatment of the isolated rat heart with commonly used contrast media enhances the cardiac tolerance to subsequent ischemia.
The mechanism behind this protective effect could not be determined, but could involve stretching of the heart and/or generation
of nitric oxide. 相似文献
70.
Cardiac metal contents after infusions of manganese. An experimental evaluation in the isolated rat heart. 总被引:2,自引:0,他引:2
RATIONALE AND OBJECTIVES: Manganese dipyridoxyl diphosphate (MnDPDP), a contrast agent for liver MRI, releases free Mn2+ in a graded manner. The aim of the study was to compare the effects of brief versus prolonged infusions of MnDPDP and manganese chloride (MnCl2) on cardiac function, metabolism, Mn accumulation, and tissue metal content. METHODS: Isolated perfused rat hearts received 1-minute or 10-minute infusions of MnDPDP (100 microM, 1000 microM) or of MnCl2 (10 microM, 100 microM). Physiologic indices were measured intermittently, and tissue high-energy phosphate compounds and Ca/Fe/Mg/Mn/Zn contents were measured after a standardized Mn washout. RESULTS: One-minute and 10-minute infusions induced, respectively, minor and marked depressions of contractile function and corresponding elevations in myocardial Mn content. MnCl2 was markedly more potent than MnDPDP. Ten-minute infusions of the highest concentration of MnDPDP and MnCl2 lowered tissue Mg and elevated tissue Ca (MnCl2), whereas high-energy phosphates were unaffected. CONCLUSIONS: Mn uptake after Mn infusion is strongly related to the duration, concentration, and dose of free Mn ions. Differences in Mn accumulation between MnDPDP and MnCl2 were more pronounced after the 10-minute infusion. 相似文献