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Recreational music exposure is a potential risk factor for noise-induced hearing loss (NIHL). Augmented hearing protectors have been designed with modified attenuation characteristics to combine hearing protection and listening comfort. However, to date, only a few independent studies have assessed the performance of those augmented protectors in realistic exposure conditions. This study compares the listening experience and temporary effects on cochlear status with different types of earplugs after exposure to contemporary club music. Five different types of commercially available hearing protectors were worn, all commonly used during leisure-time music exposure. Four of them were augmented premolded earplugs and the fifth type was an inexpensive, standard earplug frequently distributed for free at music events. During five different test sessions of 30 min each, participants not professionally involved in music wore one particular type of protector. Contemporary club music was played at sound pressure levels (SPLs) representative of concerts and bars. After each listening session, a questionnaire on sound quality and general appreciation was completed. In addition, otoacoustic emissions (OAEs) were measured directly before and after music exposure. The reported appreciation clearly differed depending on the addressed characteristics and the specific earplug type. In this test group, the reported appreciation mainly depended on comfort and looks, while differences in sound quality were less noticeable. The changes in OAE amplitude before and after noise exposure were small in terms of clinical standards. Nevertheless, the observed temporary shifts differed systematically for the different types of hearing protectors, with two types of musician earplug showing a more systematic decline than the others. Further research with respect to actual use and achieved protection for real, unsupervised music exposure is warranted.  相似文献   
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OBJECTIVE: The known risk factors for radiologic progression in rheumatoid arthritis (RA) are not optimally discriminative in patients with early disease who do not have evidence of radiologic damage. We sought to determine whether urinary C-terminal crosslinking telopeptide of type I (CTX-I) and type II (CTX-II) collagen (markers of bone and cartilage destruction, respectively) are associated with long-term radiologic progression in patients with early RA. METHODS: This was a prospective study of 110 patients with early RA who were participating in the COBRA (Combinatietherapie Bij Reumato?de Artritis) clinical trial and followup study, a randomized controlled trial comparing the efficacy of oral pulse prednisolone, methotrexate, plus sulfasalazine with sulfasalazine alone. We investigated the relationship between baseline levels of urinary CTX-I and CTX-II and the mean annual progression of joint destruction over a median of 4 years, as measured by changes in the modified Sharp score (average of 2 independent readers). RESULTS: In multivariate logistic regression analysis, baseline urinary CTX-I and CTX-II levels in the highest tertile were the strongest predictors of radiologic progression (Sharp score increase >2 units/year; odds ratio 7.9 and 11.2, respectively), independently of treatment group, erythrocyte sedimentation rate (ESR), Disease Activity Score in 28 joints, rheumatoid factor (RF), and baseline joint damage (Sharp score). The likelihood ratios for a positive test were 3.8 and 8.0 for CTX-I and CTX-II, respectively, which compared favorably with the likelihood ratios for the ESR (3.0), baseline joint damage (1.6), and RF (1.8). When patients were grouped according to the presence (Sharp score >/=4, n = 49) and absence (Sharp score <4, n = 61) of joint damage at baseline, CTX-I and CTX-II levels were predictive only in those without baseline joint damage (odds ratio 14.9 and 25.7, respectively). CONCLUSION: High baseline levels of urinary CTX-I and CTX-II independently predict an increased risk of radiologic progression over 4 years in patients with early RA, especially those without radiologic joint damage. Urinary CTX-I and CTX-II may be useful for identifying individual RA patients at high risk of progression very early in the disease, before erosions can be detected radiographically. Such patients may be in special need of treatments that inhibit bone and cartilage degradation.  相似文献   
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Plasma volume and blood pressure regulation in hypertensive pregnancy.   总被引:2,自引:0,他引:2  
BACKGROUND: Pre-eclampsia is a multisystem disorder, peculiar to and frequent in human pregnancy. It remains a leading cause of maternal and neonatal morbidity and mortality. Hemodynamic disturbances are the most prominent features of the syndrome. PURPOSE: To provide an overview of plasma volume regulation and blood pressure control mechanisms outside pregnancy, and of the changes in normal pregnancies and in pregnancies complicated by hypertensive disorders. Furthermore, to discuss the rationale of several hemodynamic interventions. RESULTS: In normal pregnancy, large cardiovascular changes take place. A generalized fall in vascular tone by systemic vasorelaxation causes increased blood volume, heart rate and cardiac output. In the preclinical phase, differences have been observed between normal and hypertensive pregnancies in the function of the autonomic nervous system, cardiac output and plasma volume, the volume remaining at the non-pregnant level. In the clinical phase of pre-eclampsia the typical case picture is one of a vasoconstrictive state with low plasma volume and cardiac output, high blood pressure and systemic vascular resistance in combination with signs of organ damage [proteinuria, hemolysis elevated liver enzymes low platelets (HELLP) syndrome]. Hemodynamic management is necessary in severe disease to prevent maternal complications. Management primarily focuses on pharmacological treatment of blood pressure. Clinicians make educated choices from a limited array of available drugs: beta-receptor antagonists, nifedipine, dihydralazine, methyldopa or ketanserine. Other drugs have restricted use in pregnancy. Management of low circulating volume with plasma expanders remains a subject of controversy.  相似文献   
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This paper reports on the identification and full chemical characterization of isotonitazene (N,N‐diethyl‐2‐[5‐nitro‐2‐({4‐[(propan‐2‐yl)oxy]phenyl}methyl)‐1H‐benzimidazol‐1‐yl]ethan‐1‐amine), a potent NPS opioid and the first member of the benzimidazole class of compounds to be available on online markets. Interestingly, this compound was sold under the name etonitazene, a structural analog. Identification of isotonitazene was performed by gas chromatography mass spectrometry (GC–MS) and liquid chromatography time‐of‐flight mass spectrometry (LC‐QTOF‐MS), the latter identifying an exact‐mass m/z value of 411.2398. All chromatographic data indicated the presence of a single, highly pure compound. Confirmation of the specific benzimidazole regio‐isomer was performed using 1H and 13C NMR spectroscopy, after which the chemical characterization was finalized by recording Fourier‐transform (FT‐IR) spectra. A live cell‐based reporter assay to assess the in vitro biological activity at the μ‐opioid receptor (MOR) revealed that isotonitazene has a high potency (EC50 of 11.1 nM) and efficacy (Emax 180% of that of hydromorphone), thus confirming that this substance is a strong opioid. Isotonitazene has not been previously detected, either in powder form, or in biological fluids. The high potency and efficacy of isotonitazene, combined with the fact that this compound was being sold undiluted, represents an imminent danger to anyone aiming to use this powder.  相似文献   
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European Child & Adolescent Psychiatry - The Strengths and Difficulties Questionnaire (SDQ) is widely used, based on evidence of its value for screening. This evidence primarily regards the...  相似文献   
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