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991.
Abstract

Objective: The aim was to investigate the influence of environmental exposures on hearing loss in a twin cohort. Study sample: Male twins born 1914–1958, representing an unscreened population, were tested for hearing loss at two occasions, 18 years apart. Design: Clinical audiometry and a questionnaire were performed at both time points in this longitudinal study. Noise and solvent exposure were assessed using occupational work codes and a job exposure matrix. Hearing impairment was investigated using two different pure tone averages: PTA4 (0.5, 1, 2, and 4?kHz) and HPTA4 (3, 4, 6, and 8?kHz). Results: Age affected all outcome measures. Noise exposure between time point one and two affected the threshold shifts of PTA4 and HPTA4 more in participants with a pre-existing hearing loss at time point one. Lifetime occupational noise exposure was a risk factor especially for the low-frequency hearing threshold PTA4. Firearm use was a statistically significant risk factor for all outcome measures. Conclusions: Pre-existing hearing loss can increase the risk of hearing impairment due to occupational noise exposure. An increased risk for NIHL was also seen in the group with exposures below 85?dB(A), a result that indicates awareness of NIHL should be raised even for those working in environments where sound levels are below 85?dB(A).  相似文献   
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Down screening has been available within clinical practice for over 50 years during which time significant innovation and exciting new advances have improved the accuracy and safety of screening, and improved choice for women who are considering antenatal screening for Down syndrome. The UK National Screening Committee is responsible for setting the national standards regarding screening and it has steadily and consistently directed and facilitated an increase in the detection rate whilst minimising the screen positive rate of Down syndrome screening. This has reduced the number of false positive results and consequently the number of invasive diagnostic procedures and their related miscarriages. Non-invasive pre-natal testing (NIPT) using cell free DNA is a rapidly evolving field and it will soon be incorporated into the existing NHS antenatal screening programme for aneuploidy. It will be offered to women who receive a ‘high risk’ result following current screening methods (combined test or quadruple test), and will further reduce the number of invasive tests performed, whilst maintaining current detection rates.  相似文献   
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3,4-Methylenedioxymethamphetamine (MDMA), popularly known as the illicit drug "Ecstasy," is an amphetamine derivative that has become widely abused throughout the United States and other industrialized nations. 3,4-Methylenedioxymethamphetamine has an undeserved reputation as a "safe" drug among its users, but MDMA shares the toxicity profile of other amphetamines. Its use may result in lethal cardiovascular, hepatic, metabolic, or neurological toxicity. The syndrome of inappropriate secretion of antidiuretic hormone (SIADH) is a unique toxicity that may occur after isolated MDMA use. Although the phenomenon is well described in adults, reports of MDMA-induced SIADH and symptomatic hyponatremia in children are rare. We describe a 13-year-old girl who experienced MDMA-induced SIADH with symptomatic hyponatremia. Toxicity of MDMA, in particular, the pathophysiology and treatment of MDMA-induced hyponatremia, is discussed.  相似文献   
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A case study of pneumococcal vaccinations shows how two tools can help hospitals use existing health information technology to improve performance.  相似文献   
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