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921.

Background and purpose

Safety and efficacy of intravenous (IV) thrombolysis and endovascular therapy in children with acute ischemic stroke (AIS) are unknown to date. We aimed to review and synthesize currently available evidence on these acute recanalization therapies in pediatric stroke patients.

Methods

We performed a systematic review and meta-analysis of all available data on safety and efficacy of acute treatment including thrombolysis and endovascular therapy in pediatric AIS patients aged <18 years. We searched the electronic databases Medline and Cochrane Library for eligible studies published from the earliest date available until August 31, 2016. Safety outcomes included intracerebral hemorrhage (ICH) post-treatment and in-hospital mortality. Efficacy outcomes included functional outcome 3–6 months after index stroke.

Results

We identified 222 records, of which 3 studies with a total of 16,987 pediatric stroke patients met our eligibility criteria of whom 181 received IV thrombolysis. No data exists from randomized trials and no data is available on endovascular thrombectomy. Risk of any ICH was increased in children receiving thrombolysis (risk ratio = 3.48, 95%CI: 1.66–7.29; p = 0.001) compared with controls, with no evidence of heterogeneity (I2 = 0%). None of the included studies reported complete data on symptomatic ICH. In-hospital mortality was similar between pediatric stroke patients treated with thrombolysis and controls (risk ratio = 1.44, 95%CI: 0.39–5.40; p = 0.586), with evidence of heterogeneity (I2 = 62%). Efficacy of revascularization therapies could not be analyzed due to lack of outcome data.

Conclusions

Our analyses demonstrate a substantial lack of data on efficacy and safety of acute recanalization therapies in children with AIS.

PROSPERO Registration Information

URL: http://www.crd.york.ac.uk/PROSPERO. Unique identifier: CRD42016047140.  相似文献   
922.
Reports for pediatric kidney transplant recipients suggested better outcomes for ODN compared to LDN. Contemporary outcomes stratified by donor type and center volume have not been evaluated in a national dataset. UNOS data (2000‐2014) were analyzed for pediatric living donor kidney transplant recipients. The primary outcome was GF; secondary outcomes were DGF, rejection, and patient survival. Live donor nephrectomies for pediatric recipients decreased 30% and transitioned from ODN to LDN. GF rates did not differ for ODN vs LDN (P = .24). GF was lowest at high volume centers (P < .01). Donor operative approach did not contribute to GF. LDN was associated with less rejection than ODN (OR 0.66, CI 0.5‐0.87, P < .01). Analysis of the 0‐ to 5‐yr recipient group showed no effect of ODN vs LDN on GF or rejection. For the contemporary era, there was no association between DGF and LDN in the 0‐ to 5‐yr group (OR 1.12, CI 0.67‐1.89, P = .67). Outcomes of kidney transplants in pediatric recipients following LDN have improved since its introduction and LDN should be the approach for live donor nephrectomy regardless of recipient age. The association between case volume and improved outcomes highlights future challenges in organ transplantation.  相似文献   
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AIMS: The aim of the present study was to analyse the incidence of violence and threats of violence during the first year at work after graduating as a healthcare worker, the risk of re-exposure and health effects among respondents previously exposed to violence or threats. METHODS: We analysed baseline data from 5,696 healthcare students and conducted prospective multinomial regression analyses following 2,847 respondents during their first year of employment. RESULTS: At baseline we found that nearly a third of the respondents had been exposed to violence or threats of violence, 8.7% during trainee periods. At follow-up, we found that 24.6% of the healthcare workers had been exposed to violence and 33.4% to threats during the first year at work after graduation. Exposure to violence or threats during trainee periods was a strong predictor of violence (Odds ratio (OR)=3.3) and threats (OR=4.2) at follow-up. The results showed that violence or threats in previous jobs or at other places had a significant impact on the health of the victims at follow-up independent of gender, age, sense of coherence, self-efficacy and health at baseline. Exposure during trainee periods had a small but not quite significant (p=0.06) impact on the health of the victims at follow-up. CONCLUSIONS: The study shows a high risk of violence and threats of violence among healthcare workers during training and the first year at work after graduation, indicating a need for violence prevention planning involving both college and workplaces.  相似文献   
926.
Increased levels of Cu in agricultural soils are of concern, because Cu toxicity may adversely affect important soil microorganisms, including pseudomonads. Because total metal concentrations correlate poorly with bioavailability and toxicity, a need exists for more information linking Cu speciation, bioavailability, and toxicity. The objective of the present study was to determine the bioavailability of different Cu complexes to Pseudomonas spp. A Cu-specific bioluminescent Pseudomonas fluorescens reporter strain was used to determine bioavailable Cu, which was operationally defined as those Cu species that induced expression of bioluminescence. Another strain of P. fluorescens, which continuously expressed bioluminescence, was used as a toxicity reporter. Experiments were performed in a defined aqueous medium containing 0.04 microM Cu, which was amended with ethylenediaminetetraacetic acid (EDTA), citrate, or a well-characterized pool of dissolved organic matter (DOM). Bioluminescence emitted by the biosensors was related to data for Cu speciation obtained by geochemical modeling. Changes in Cu bioavailability in the presence of EDTA coincided with modeled changes in Cu2+ activity, indicating that Cu-EDTA complexes were not bioavailable to the Cu-specific reporter. In contrast, changes of Cu bioavailability in the presence of citrate did not correspond to changes in Cu2+, indicating that Cu-citrate complexes were fully bioavailable to the reporter strain. Finally, the response of the Cu-reporter strain to Cu in the presence of DOM indicated that Cu formed bioavailable as well as unavailable complexes with DOM. We conclude that free Cu2+ activity is a poor predictor of Cu bioavailability to Pseudomonas spp. in samples containing organic ligands.  相似文献   
927.
OBJECTIVE: The objective of this paper is to describe the problem of multiple comparisons in systematic reviews and to provide some guidelines on how to deal with it in practice. STUDY DESIGN AND SETTING: We describe common reasons for multiplicity in systematic reviews, and present some examples. We provide guidance on how to deal with multiplicity when it is unavoidable. RESULTS: We identified six common reasons for multiplicity in systematic reviews: multiple outcomes, multiple groups, multiple time points, multiple effect measures, subgroup analyses, and multiple looks at accumulating data. The existing methods to deal with multiplicity in single trials can not always be applied in systematic reviews. CONCLUSION: There is no simple and completely satisfactory solution to the problem of multiple comparisons in systematic reviews. More research is required to develop multiple comparison procedures for use in systematic reviews. Authors and consumers of systematic reviews should give serious attention to multiplicity in systematic reviews when presenting, interpreting and using the results of these reports.  相似文献   
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Introduction: Assessment of membrane properties is important for understanding the mechanisms of painful peripheral neuropathy, developing new diagnostic techniques, and screening/profiling of analgesics that target ion channels. Methods: Small cutaneous nerves were activated electrically by small diameter (0.2 mm) cathodes, and large nerves were activated by ordinary patch electrodes. This new perception threshold tracking method combines perception threshold assessment and stimulation paradigms from conventional threshold tracking. Results: The strength‐duration time‐constant of large fibers (580 µs ± 160 µs) was lower than the time constant of small fibers (1060 µs ± 690 µs; P < 0.01, paired t‐test). Threshold electrotonus showed similar threshold reductions to sub‐threshold prepulses, except for 80 ms hyperpolarizing prepulses, to which small fibers showed less threshold reduction than large fibers (repeated‐measures analysis of variance, Bonferroni, P = 0.006). Conclusions: This is a reliable method to investigate the membrane properties of small cutaneous nerve fibers in humans and may be used in clinical settings as a diagnostic or profiling tool. Muscle Nerve 55 : 195–201, 2017  相似文献   
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