653 research outputs found

    Исследование влияния давления в реакторах на процесс каталитического риформинга бензинов

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    Freeman-Sheldon syndrome is defined as a combination of microstomia, deep set eyes, small palpebral fissures, arthrogryposis with ulnar deviation of the hand, talipes equinovarus and generalized muscular hypertension. Respiratory and swallowing problems are frequently encountered in these patients due to small orifices of mouth and nose. Obstruction of the upper airway tract resulting in tracheostomy has only been described twice. The described child manifested the typical dysmorphic features of Freeman-Sheldon syndrome and suffered from serious respiratory distress and swallowing difficulties from birth. The boy died at the age of 7 months after accidental decannulation of the tracheostoma during sleep. He did not show anatomical or histopathological abnormalities in the pharyngeal, laryngeal or tracheal regions. We assume that the only explanation of the repeated obstructive episodes is a functional muscular obstruction. Copyright © 2002 S. Karger AG, Basel

    Residual effects of esmirtazapine on actual driving performance: overall findings and an exploratory analysis into the role of CYP2D6 phenotype

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    INTRODUCTION: Esmirtazapine is evaluated as a novel drug for treatment of insomnia. PURPOSE: The present study was designed to assess residual effects of single and repeated doses of esmirtazapine 1.5 and 4.5 mg on actual driving in 32 healthy volunteers in a double-blind, placebo-controlled study. Treatment with single doses of zopiclone 7.5 mg was included as active control. METHODS: Treatments were administered in the evening. Driving performance was assessed in the morning, 11 h after drug intake, in a standardized on-the-road highway driving test. The primary study parameter was standard deviation of lateral position (SDLP), a measure of "weaving". All subjects were subjected to CYP2D6 phenotyping in order to distinguish poor metabolizers from extensive metabolizers of esmirtazapine. RESULTS: Overall, esmirtazapine 1.5 mg did not produce any clinically relevant change in SDLP after single and repeated dosing. Driving impairment, i.e., a rise in SDLP, did occur after a single-dose administration of esmirtazapine 4.5 mg but was resolved after repeated doses. Acute driving impairment was more pronounced after both doses of esmirtazapine in a select group of poor metabolizers (N = 7). A single-dose zopiclone 7.5 mg also increased SDLP as expected. CONCLUSION: It is concluded that single and repeated doses of 1.5 mg esmirtazapine are generally not associated with residual impairment. Single-dose administration of 4.5 mg esmirtazapine was associated with residual impairment that generally resolved after repeated administration. Exploratory analysis in a small group of poor CYP 2D6 metabolizers suggested that these subjects are more sensitive to the impairing effects of esmirtazapine on car driving

    The sensitivity of laboratory tests assessing driving related skills to dose-related impairment of alcohol:A literature review

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    AbstractLaboratory tests assessing driving related skills can be useful as initial screening tools to assess potential drug induced impairment as part of a standardized behavioural assessment. Unfortunately, consensus about which laboratory tests should be included to reliably assess drug induced impairment has not yet been reached. The aim of the present review was to evaluate the sensitivity of laboratory tests to the dose dependent effects of alcohol, as a benchmark, on performance parameters. In total, 179 experimental studies were included. Results show that a cued go/no-go task and a divided attention test with primary tracking and secondary visual search were consistently sensitive to the impairing effects at medium and high blood alcohol concentrations. Driving performance assessed in a simulator was less sensitive to the effects of alcohol as compared to naturalistic, on-the-road driving. In conclusion, replicating results of several potentially useful tests and their predictive validity of actual driving impairment should deserve further research. In addition, driving simulators should be validated and compared head to head to naturalistic driving in order to increase construct validity

    The influence of alcohol (0.5‰) on the control and manoeuvring level of driving behaviour, finding measures to assess driving impairment:A simulator study

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    Objective: The influence of psychoactive substances on driving performance and traffic safety has been extensively studied. Research on the influence of alcohol at the control level of behaviour (i.e. automated processes) has been well established and has shown that the ability to operate a vehicle decreases with rising alcohol levels. However, results one level higher at the manoeuvring level (i.e. conscious processes), are inconsistent. The current study aimed to replicate findings on the influence of alcohol on the control level of behaviour and investigate effects on the manoeuvring level in order to find suitable measures to assess driving impairment. Method: The study was double-blind, placebo-controlled with a counterbalanced treatment order and a two-way crossover design. Thirty participants performed tasks in a driving simulator under the influence of alcohol (0.5‰) and a placebo. In the driving tasks the control level of behaviour (swerving, average speed, and speed variation) was investigated, as well as the manoeuvring level of behaviour (distance to other traffic during an overtaking manoeuvre, reaction time to a traffic light turning amber, and response to a suddenly merging car). Results: As expected, alcohol affected the control level of behaviour negatively. Participants swerved more and showed more speed variation after alcohol intake. The manoeuvring level of driving behaviour was also affected by alcohol. The distance to other drivers during an overtaking manoeuvre was smaller under the influence of alcohol. Results on reaction time were however less straightforward. Reaction time increased significantly under the influence of alcohol when reacting to a traffic light but not in reaction to a car unexpectedly merging into traffic. When analysing behaviour in reaction to these different events in more detail it became clear that they were responded to in varying manners, making it difficult to find an average impairment measure. Conclusions: The deteriorating effect of alcohol at the control level of driving behaviour was replicated, confirming the suitability of the standard deviation of lateral position and the variation in speed as measures of impairment. At the manoeuvring level, the kept distance to the leading car during an overtaking manoeuvre appeared to be a suitable measure to assess impairment as well as reaction time to a traffic light. The current study also confirms the difficulties in evaluating complex driving behaviour and the need for more research on this subject

    Driving performance and neurocognitive skills of long-term users of sedating antidepressants

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    Objective: To assess driving performance and neurocognitive skills of long‐term users of sedating antidepressants, in comparison to healthy controls. Methods: Thirty‐eight long‐term (>6 months) users of amitriptyline (n = 13) and mirtazapine (n = 25) were compared to 65 healthy controls. Driving performance was assessed using a 1‐h standardised highway driving test in actual traffic, with road‐tracking error (standard deviation of lateral position [SDLP]) being the primary measure. Secondary measures included neurocognitive tasks related to driving. Performance differences between groups were compared to those of blood alcohol concentrations of 0.5 mg/ml to determine clinical relevance. Results: Compared to controls, mean increase in SDLP of all antidepressant users was not significant, nor clinically relevant (+0.75 cm, 95% CI: - 0.83 cm; +2.33 cm). However, users treated less than 3 years (n = 20) did show a significant and clinically relevant increase in SDLP (+2.05 cm). No significant effects were observed on neurocognitive tasks for any user group, although large individual differences were present. Most results from neurocognitive tests were inconclusive, while a few parameters confirmed non‐inferiority for users treated longer than 3 years. Conclusion: The impairing effects of antidepressant treatment on driving performance and neurocognition mitigate over time following long‐term use of 3 years

    Ayahuasca enhances creative divergent thinking while decreasing conventional convergent thinking

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    INTRODUCTION: Ayahuasca is a South American psychotropic plant tea traditionally used in Amazonian shamanism. The tea contains the psychedelic 5-HT2A receptor agonist N,N-dimethyltryptamine (DMT), plus β-carboline alkaloids with monoamine oxidase-inhibiting properties. Increasing evidence from anecdotal reports and open-label studies indicates that ayahuasca may have therapeutic effects in treatment of substance use disorders and depression. A recent study on the psychological effects of ayahuasca found that the tea reduces judgmental processing and inner reactivity, classic goals of mindfulness psychotherapy. Another psychological facet that could potentially be targeted by ayahuasca is creative divergent thinking. This mode of thinking can enhance and strengthen psychological flexibility by allowing individuals to generate new and effective cognitive, emotional, and behavioral strategies. The present study aimed to assess the potential effects of ayahuasca on creative thinking. METHODS: We visited two spiritual ayahuasca workshops and invited participants to conduct creativity tests before and during the acute effects of ayahuasca. In total, 26 participants consented. Creativity tests included the "pattern/line meanings test" (PLMT) and the "picture concept test" (PCT), both assessing divergent thinking and the latter also assessing convergent thinking. RESULTS: While no significant effects were found for the PLMT, ayahuasca intake significantly modified divergent and convergent thinking as measured by the PCT. While convergent thinking decreased after intake, divergent thinking increased. CONCLUSIONS: The present data indicate that ayahuasca enhances creative divergent thinking. They suggest that ayahuasca increases psychological flexibility, which may facilitate psychotherapeutic interventions and support clinical trial initiatives
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