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A World Health Organization Expert Committee has concluded that symptoms of methylmercury poisoning may appear at blood concentrations of 200-500 ng Hg/ml. Blood levels in this range have been found in several Indian and Inuit communities in Canada. The syndrome of severe methylmercury poisoning (Hunter-Russell syndrome) is well described. However, diagnosis of less severe cases is difficult. This paper review the present situation in Canada. The problems of diagnosis currently being encountered are discussed and are illustrated by the case of an individual who had one of the highest blood concentrations (551 ng Hg/ml) ever described in fish-eating populations outside of the outbreaks in Minamata and Niigata in Japan. Although mercury concentrations in brain were estimated to have been in the "symptomatic" range at least once in the two years prior to his death, neurohistological examination was normal. Detailed examination by two teams of neurologists revealed effects that may be associated with methylmercury poisoning but a definitive diagnosis remained elusive.  相似文献   
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This paper reports the results of a postal questionnaire, with a response rate of 61 per cent. It is clear from the results that subtotal hysterectomy is an unpopular operation in the United Kingdom. Although a majority of consultants felt that subtotal hysterectomy was less likely to affect urinary, bowel and sexual function, this did not seem to affect decision making. Seventy-eight per cent of female gynaecologists would prefer a total hysterectomy for themselves rather than a subtotal procedure.  相似文献   
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Medical devices and their associated process equipment must be reliable and fit for purpose. In light of the recent changes to the medical device regulations, manufacturers must now take an integrated approach to design, development and validation. Good design practice encourages this integrated approach while ensuring fitness for purpose within commercial reality. A review of current literature related to good design practice carried out in Part I of this paper showed that there is inadequate guidance regarding the integration of validation with design. This paper proposes a practical approach to design for validation aimed at making devices easier and more economic to validate. The approach comes in the form of a model of design for validation that illustrates the basic relationship between design, development and validation and a series of design tactics that were formulated in order to help designers take a more proactive approach to validation during design.  相似文献   
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ABSTRACT: The presentation of carbon monoxide (CO) poisoning is non-specific and highly variable. The diagnosis is made when a compatible history and examination occur in a patient with elevated carboxyhemoglobin levels. The severity of intoxication is difficult to assess accurately based on laboratory markers alone. Magnetic resonance imaging has been shown to have superior sensitivity to computed tomography for the detection of abnormalities post CO poisoning. We report a novel imaging pattern on MRI undertaken in the acute setting in a patient with CO intoxication.  相似文献   
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