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In Hannover/Germany in 1976 a so called "Society for Regenerative Hyperbaric Therapy" (Gesellschaft für Regenerative Uberdruck-Therapie) subjected 20 patients within two coupled multi-place chambers to a simulated hyperbaric environment, equivalent to a maximum of 4 ata, followed usually by gradual reductions of the pressure. The patients were of an average age of 67.2 years and were afflicted by various disorders. During one of the "dives" a patient developed air embolism of the central nervous system. During ensuing confusion of the chamber was opened suddenly, with resultant explosive reduction of the high pressure. This resulted in five letal accidents of decompression sickness. Post mortem examination revealed diffuse distribution of gas bubbles throughout the entire body. By elecronmicroscopy each bubble was covered by an osmiophilic coat. Post mortem findings are discussed and correlated with well-known and new clinical symptomes. These observations present for the first time fatal accidents of decompression sickness in humans, associated with hyperbaric air-therapy.  相似文献   
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The abuse of heroin (diacetylmorphine) in Singapore escalated sharply in 1975 and 1976, as indicated by the 35-fold increase in the number of heroin seizures and the 20-fold increase in the urine samples containing morphine since 1974. A rapid and simple GC method has been described to estimate diacetylmorphine (and caffeine). Monoacetylmorphine and acetylcodeine may be ascertained by an additional step involving acetylation. All gas chromatograms of a large number of samples analyzed consistently had the same pattern, indicating that they possibly had a common origin. This GC "fingerprint," together with the quantitative data, appears to be characteristic of the illicit Asian or Chinese type of heroin found in Singapore. The proportions of the four major ingredients in some twelve typical samples have been tabulated. Statistical data confirming the accuracy and reproducibility of the analytical method have also been presented.  相似文献   
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An employer's capacity successfully to survive a strike will depend largely on the extent to which it has anticipated the strike and taken the steps necessary to defend against it. It is the purpose of this article to catalog the factors employers should consider in approaching an imminent strike and devising contingency plans. It attempts to focus on the types of problems, legal and practical, that frequently arise in strike situations, and suggests certain measures that employers may adopt in preparing for, and defending against, the economic impact of a strike.  相似文献   
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