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961.
James E. Andruchow Peter A. Kavsak Andrew D. McRae 《The Canadian journal of cardiology》2018,34(2):98-108
This article synthesizes current best evidence for the evaluation of patients with suspected acute coronary syndrome (ACS) using high-sensitivity troponin assays, enabling physicians to effectively incorporate them into practice. Unlike conventional assays, high-sensitivity assays can precisely measure blood cardiac troponin concentrations in the vast majority of healthy individuals, facilitating the creation of rapid diagnostic algorithms. Very low troponin concentrations on presentation accurately rule out acute myocardial infarction (AMI) and enable the discharge of approximately 20% of patients after a single test, whereas an additional 30%-40% of patients can be safely discharged after short-interval serial sampling in as little as 1 or 2 hours. In contrast, highly abnormal troponin concentrations on presentation (more than 5 times the upper reference limit) or rapidly rising levels on serial testing can rapidly rule in AMI with high specificity. However, approximately one-third of patients remain in a biomarker-indeterminate “observation zone” even after serial sampling. These patients pose a disposition challenge to clinicians because although the differential diagnosis of elevated troponin concentrations is broad, these patients have an increased risk for short-term major adverse cardiac events. Use of repeated serial troponin sampling and structured clinical prediction tools may assist disposition for these patients, because no validated pathways currently exist to guide clinicians. Ongoing research to tailor diagnostic thresholds to individual patient characteristics may enable improved diagnostic accuracy and usher in a new era of personalized medicine in the evaluation of suspected ACS. 相似文献
962.
Linda M. Ercoli Steven A. Castellon Aimee M. Hunter Lorna Kwan Barbara A. Kahn-Mills Paul A. Cernin Andrew F. Leuchter Patricia A. Ganz 《Brain imaging and behavior》2013,7(4):543-553
To assess the feasibility of a cognitive rehabilitation program in breast cancer survivors (BCS) with persistent post-treatment cognitive complaints. BCS with cognitive complaints, 18-months to 5-years post-treatment, were recruited for a once-weekly, five-week, group cognitive training intervention. Outcome measures included self-reported mood and cognitive function, and neurocognitive tests administered at pre-intervention, immediate-, two-month and four-month post-intervention. A sub-study in eight participants evaluated resting state quantitative electroencephalography (qEEG) changes from pre- to immediate post-intervention in relationship to post-intervention changes in cognitive complaints. Twenty-seven BCS completed the protocol and tolerated the intervention well. We observed significant reductions in total and memory-specific cognitive complaints from pre-intervention to immediate post-intervention (p?=?0.031 and p?=?0.009, respectively) and at four-months post-intervention (p?<?0.0001 and p?<?0.001, respectively). Significant improvement in neurocognitive tests were found for Symbol Digit, Stroop, and Trails A tests (df?=?26, all p’s <0.05). Effect sizes for changes from pre-intervention to immediate and to four-month post intervention ranged from 0.429 to 0.607, and from 0.439 to 0.741, respectively. Increase in qEEG absolute alpha power over the course of the intervention was associated with reduced complaints at immediate post-intervention (r?=??0.78, p?=?0.021), two-months (r range?=??0.76 to ?0.82, p-value range 0.004 to 0.03), and four-months (r?=??0.71, p?=?0.048). A five-week group cognitive training intervention is feasible and well tolerated. Cognitive complaints and neurocognitive test performances showed positive changes. qEEG may serve as a potential biomarker for improvement in self-reported complaints. A randomized clinical trial is underway to test the efficacy of the intervention. 相似文献
963.
964.
965.
A. Justin Nowakowski Janna R. Willoughby J. Andrew DeWoody Maureen A. Donnelly 《Conservation Genetics Resources》2014,6(3):697-698
There are relatively few molecular resources for amphibians in the tropics where widespread habitat loss, disease, and contamination threaten the world’s most diverse assemblages. We used Illumina sequencing to develop microsatellite primers for a dominant amphibian species in Costa Rica that has recently experienced population declines. We characterized 12 polymorphic loci and have provided sequences for over 200 additional primers. These novel molecular resources will be useful for future studies of population genetic structure and may help explain recent declines in one of many species that are decreasing in Central America. 相似文献
966.
Martin Harper Khatchatur Sarkisian Michael Andrew 《Journal of occupational and environmental hygiene》2014,11(10):D157-D163
Analysis of Proficiency Analytical Testing (PAT) results between 2003 and 2013 suggest that the variation in respirable crystalline silica analysis is much smaller today than it was in the period 1990–1998, partly because of a change in sample production procedure and because the colorimetric method has been phased out, although quality improvements in the x-ray diffraction (XRD) or infrared (IR) methods may have also played a role. There is no practical difference between laboratories using XRD or IR methods or between laboratories which are accredited or those which are not. Reference laboratory means (assigned values) are not different from the means of all participants across the current range of mass loading, although there is a small difference in variance in the ratios of all participants to reference laboratory means based on method because the reference laboratories are much more likely to use XRD than are the others. Matrix interference does not lead to biases or substantially larger variances for either XRD or IR methods. Data from proficiency test sample analyses that include results from poorly performing laboratories should not be used to determine the validity of a method. PAT samples are not produced below 40 μg and variance may increase with lower masses, although this is not particularly predictable. PAT data from lower mass loadings will be required to evaluate analytical performance if exposure limits are lowered without change in sampling method. Task-specific exposure measurements for periods shorter than a full shift typically result in lower mass loadings and the quality of these analyses would also be better assured from being within the range of PAT mass loadings. High flow rate cyclones, whose performance has been validated, can be used to obtain higher mass loadings in environments of lower concentrations or where shorter sampling times are desired. 相似文献
967.
William L. Smith Spencer R. Hedges Eli Mordechai Martin E. Adelson Jason P. Trama Scott E. Gygax Andrew M. Kaunitz David W. Hilbert 《Journal of clinical microbiology》2014,52(8):3078-3081
Matched vaginal and cervical specimens from 96 subjects were analyzed by quantitative PCR for the presence and concentration of bacterial vaginosis-associated microbes and commensal Lactobacillus spp. Detection of these microbes was 92% concordant, indicating that microbial floras at these body sites are generally similar. 相似文献
968.
GPCR signaling is modified both in major depressive disorder and by chronic antidepressant treatment. Endogenous Gαs redistributes from raft- to nonraft-membrane fractions after chronic antidepressant treatment. Modification of G protein anchoring may participate in this process. Regulation of Gαs signaling by antidepressants was studied using fluorescence recovery after photobleaching (FRAP) of GFP-Gαs. Here we find that extended antidepressant treatment both increases the half-time of maximum recovery of GFP-Gαs and decreases the extent of recovery. Furthermore, this effect parallels the movement of Gαs out of lipid rafts as determined by cold detergent membrane extraction with respect to both dose and duration of drug treatment. This effect was observed for several classes of compounds with antidepressant activity, whereas closely related molecules lacking antidepressant activity (eg, R-citalopram) did not produce the effect. These results are consistent with previously observed antidepressant-induced translocation of Gαs, but also suggest an alternate membrane attachment site for this G protein. Furthermore, FRAP analysis provides the possibility of a relatively high-throughput screening tool for compounds with putative antidepressant activity. 相似文献
969.
Upper tract malignancies represent an estimated 5 %–10 % of urothelial cancers, with roughly 3,000 new cases per year in the United States. These tumors often present at an advanced stage, with invasion and lymph node metastases. There are no large randomized prospective studies demonstrating the benefit of lymph node dissection in upper tract urothelial cancer, and as such, definitive guidelines on the surgical template and timing are lacking. Laparoscopic and robotic-assisted surgical techniques are well-established for nephroureterectomy, but are also emerging for retroperitoneal lymph node dissection. The treatment of these tumors still needs to be tailored based on patient and tumor characteristics. The purpose of our review is to update findings on the utility, techniques, and outcomes of lymphadenectomy for upper tract urothelial cancer. 相似文献
970.
Andrew Ian Jenkins Mary Louise Hughes Efthymia Mantzourani Mathew Wayne Smith 《Journal of interprofessional care》2016,30(5):678-681
In recent years, the delivery of health services has seen a shift towards interprofessional teamwork in order to effectively utilise the skills of each member of the healthcare team to deliver optimal patient care. Nevertheless, a variety of barriers, including lack of communication between healthcare professionals (HCPs), have been identified. The expanding clinical services provided by community pharmacies have increased the potential for pharmacist-HCP interaction; however, primary care pharmacy environments vary from individual distinct premises to part of interprofessional ‘health centres’. As such, one potential factor affecting interprofessional communication could be the geographical location (‘space’) of HCPs. This study sought to determine whether these different primary healthcare ‘spaces’ impact on the frequency of interprofessional interactions. An anonymous, self-complete questionnaire was sent to all community pharmacies in Wales (n = 716) to quantify the frequency of interprofessional interactions between community pharmacists and other HCPs. A response rate of 62% was achieved. Results showed that pharmacists working in pharmacies physically linked to general practitioner (GP) surgeries had significantly more frequent interaction with HCPs based within the surgeries. This suggests that housing HCPs in the same physical space will enable more interprofessional interaction, supporting the drive to improve the quality of patient care. 相似文献