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1.
To improve the diagnostic accuracy of electroencephalography (EEG) criteria for nonconvulsive status epilepticus (NCSE), external validation of the recently proposed Salzburg criteria is paramount. We performed an external, retrospective, diagnostic accuracy study of the Salzburg criteria, using EEG recordings from patients with and without a clinical suspicion of having NCSE. Of the 191 EEG recordings, 12 (12%) was classified as an NCSE according to the reference standard. In the validation cohort, sensitivity was 67% and specificity was 89%. The positive predictive value was 47% and the negative predictive value was 95%. Ten patients in the control group (n = 93) were false positive, resulting in a specificity of 89.2%. The interrater agreement between the reference standards and between the scorers of the Salzburg criteria was moderate; disagreement occurred mainly in patients with an epileptic encephalopathy. The Salzburg criteria showed a lower diagnostic accuracy in our external validation study than in the original design, suggesting that they cannot replace the current practice of careful weighing of both clinical and EEG information on an individual basis.  相似文献   
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INTRODUCTION: One-third of children with epilepsy are classified as having a cryptogenic localization related epilepsy (CLRE). In cohort studies CLRE is often grouped together with either symptomatic localization related epilepsy (SLRE) or idiopathic generalized epilepsy (IGE). Therefore, this categorization is not specific enough and will not lead to prognostic or treatment information. We objectified the classification differences between these categories. METHODS: A total of 114 children admitted to our epilepsy centre underwent a standardized clinical analysis, which yielded age at onset, duration of the epilepsy, seizure frequency, seizure type, percentage of interictal epileptiform activity on EEG (IEA), type of treatment, and full scale IQ. These variables are regarded the characteristics of the epilepsy, and used in a discriminant function analysis. RESULTS: IEA was found to be the only variable to distinguish between groups of epilepsy. SLRE could easily be distinguished significantly from IGE and CLRE, while the latter two did not differ significantly. Discriminant function analysis combined the variables into two functions, applicable to classify the children. By applying this statistical analysis method, the groups clinically classified as SLRE and IGE were mostly classified as SLRE (71.4%) and IGE (57.9%). However, CLRE appeared difficult to classify (49.2%), and most children were classified as either SLRE (19%) or IGE (31.7%). CONCLUSION: The current opinion that CLRE is 'probably symptomatic' cannot be confirmed in all cases in this study. It is most likely that the current CLRE population consists of both children with eventually SLRE, as well as yet to be described syndromes to be classified as idiopathic epilepsies. We emphasize the need for separate studies regarding children with 'probably symptomatic' (cryptogenic) localization related epilepsy, as this will maximally help children, caretakers and treating physicians to achieve the best possible outcome.  相似文献   
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OBJECTIVE: The GRIF automated feedback system produces real-time comments on the appropriateness of diagnostic tests ordered by general practitioners (GPs) based on recommendations from accepted national and regional practice guidelines. We investigated the experiences of GPs with this system and, more specifically, with the recommendations produced by the system as well as their views on using this system in daily practice. SETTING: We tested the GRIF system in an experiment in a laboratory setting and in a daily practice trial. STUDY PARTICIPANTS: General practitioners. INTERVENTION: In the laboratory experiment, GPs used the GRIF system to assess the appropriateness of 30 request forms. Each of the GPs was confronted with requests they had submitted to the diagnostic unit of the hospital in the past. In the field trial, the GRIF system was applied during patient consultations for 1 year. MAIN OUTCOME MEASURES: We measured GPs' satisfaction with the system using a questionnaire, and also conducted group discussions (in the laboratory experiment) and in-depth interviews (in the field trial) to elicit GPs' opinions of and experiences with the system. In addition, we explored GPs' reasons for not accepting the comments offered by the GRIF system. RESULTS: The results show that the GPs in the laboratory experiment had more positive attitudes towards the system compared with participants in the field trial. All discussion groups and most of the GPs in the field trial regarded receiving the immediate feedback during the test ordering process as an important advantage. The most frequently mentioned reason to reject the recommendation was disagreement with the content and/or the recommendations in the practice guidelines. CONCLUSION: Apart from securing agreement on guideline content, a prerequisite for using GRIF in daily practice on a large scale is that more attention is paid to promotion of the guidelines and their adoption, and stimulation of a positive attitude towards the practice guidelines among the users.  相似文献   
4.
A trial of the efficacy of aspirin in the prevention of thrombotic occlusion of an "aortic loop" in rats was made simultaneously by two experimental surgeons. A relatively large dose of aspirin (80-100 mg/kg/day) was used, starting two days before operation. It appeared that aspirin was of limited benefit, reducing thrombotic occlusions by about 17% seven days after the insertion of the loop into the abdominal aorta. Although the average occlusion time was prolonged by about 17% in aspirin-treated animals, the separate trials gave no conclusive result. When the data from both operators were pooled, a statistically significant protection by aspirin was apparent (p = 0.02), by a two-tailed Student's t test. However, on using the powerful non-parametric randomization test, the occlusion times in control and aspirin-treated groups appeared not statistically different (p = 0.07). No significant difference was also found between control and treated groups when data were analyzed by X2 test. Independently of the statistical analysis, these data are quite similar to those obtained from aspirin trials in men surviving myocardial infarction. This finding points to the usefulness of the aorta loop as an animal model for arterial thrombosis.  相似文献   
5.
In the present intervention study we compared the effects of alpha-linolenic acid with those of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) on platelet aggregation in vitro and ex vivo in healthy non-institutionalized elderly subjects. We also compared the effects of alpha-linolenic acid on platelet aggregation in elderly subjects with those in younger volunteers. During a run-in period of 3 weeks all subjects (thirty-eight elderly (> 60 years) and twelve younger volunteers (< 35 years)) received a diet rich in oleic acid. For the next 6 weeks the elderly subjects received a diet rich in oleic acid (n 11), alpha-linolenic acid (n 14) (6.8 g/d) or EPA/DHA (n 13) (1.05 g EPA plus 0.55 g DHA). The younger subjects were given a diet rich in alpha-linolenic acid. The diets did not affect ADP- or collagen-induced platelet aggregation in vitro in either platelet-rich plasma or whole blood. The ex vivo platelet aggregation as measured with filtragometry was significantly decreased in the elderly group that received EPA/DHA compared with the alpha-linolenic acid (P = 0.006) and the oleic acid (P = 0.005) diet groups. Effects of alpha-linolenic acid were not age-dependent. Our results suggest that alpha-linolenic acid and EPA/DHA do not change in vitro platelet aggregation. Compared with oleic acid, EPA/DHA, but not alpha-linolenic acid, favourably affects ex vivo platelet aggregation in healthy elderly subjects.  相似文献   
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BackgroundClinical prediction rules (CPRs) to identify children with serious infections lack validation in low-prevalence populations, which hampers their implementation in primary care practice.AimTo evaluate the diagnostic value of published CPRs for febrile children in primary care.MethodAlarm signs of serious infection and clinical management were extracted from routine clinical practice data and manually recoded with a structured electronic data-entry program. Eight CPRs were selected from literature. CPR-variables were matched with alarm signs and CPRs were applied to the GPC-population. ‘Referral to emergency department (ED)’ was used as a proxy outcome measure for ‘serious infection’. CPR performance was assessed by calibration analyses, sensitivity, specificity, and area under the ROC-curve (ROC-area).ResultsA total of 9794 GPC-contacts were eligible, 54% male, median age 2.3 years (interquartile range 1.0–4.6 years) and 8.1% referred to ED. Frequencies of CPR-variables varied from 0.5% (cyanosis, drowsy) to 25% (temperature ≥40°C). Alarm signs frequently included in CPRs were ‘ill appearance’, ‘inconsolable’, and ‘abnormal circulatory or respiratory signs’. The height of the CPR’s predicted risks generally corresponded with being (or not being) referred to the ED in practice. However, calibration-slopes indicated that three CPRs underestimated the risk of serious infection in the GPC-population. Sensitivities ranged from 42% to 54%, specificities from 68% to 89%. ROC-areas ranged from 0.52 to 0.81, with best performance of CPRs for children aged <3 months.ConclusionPublished CPRs performed moderately well in the primary out-of-hours care population. Advice is given on how to improve translation of CPRs to primary care practice.  相似文献   
9.
Cardiovascular Drugs and Therapy - Sonlicromanol is a phase IIB clinical stage compound developed for treatment of mitochondrial diseases. Its active component, KH176m, functions as an antioxidant,...  相似文献   
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